diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmDialog.h b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmDialog.h
index bd8dd4243220596c3221de07255d3be75645acd9..329b48270f302db912e8d34dd487abdf5c9012fc 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmDialog.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_ALGORITHMDIALOG_H_
-#define MANTIDQT_API_ALGORITHMDIALOG_H_
+#pragma once
 
 /* Used to register classes into the factory. creates a global object in an
  * anonymous namespace. The object itself does nothing, but the comma operator
@@ -343,5 +342,4 @@ protected:
   //@}
 };
 } // namespace API
-} // namespace MantidQt
-#endif // MANTIDQT_API_ALGORITHMDIALOG_H_
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmDialogFactory.h b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmDialogFactory.h
index 4fef8732580cc06dc7213a284d705b604149bc0d..d478efc8031bbc62158fbc59f6a954efdd87c807 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmDialogFactory.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmDialogFactory.h
@@ -5,8 +5,7 @@
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
 
-#ifndef MANTIDQT_API_ALGORITHMDIALOGFACTORYIMPL_H_
-#define MANTIDQT_API_ALGORITHMDIALOGFACTORYIMPL_H_
+#pragma once
 
 //------------------------
 // Includes
@@ -67,5 +66,4 @@ namespace Kernel {
 EXTERN_MANTIDQT_COMMON template class EXPORT_OPT_MANTIDQT_COMMON
     Mantid::Kernel::SingletonHolder<MantidQt::API::AlgorithmDialogFactoryImpl>;
 } // namespace Kernel
-} // namespace Mantid
-#endif
\ No newline at end of file
+} // namespace Mantid
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmHintStrategy.h b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmHintStrategy.h
index 0cdaa3938206c07e33b8b0b88990b160fd5294e2..85ae08b4bc47c381ae9c9bd8b1d6189510085237 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmHintStrategy.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmHintStrategy.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_ALGORITHMHINTSTRATEGY_H
-#define MANTID_MANTIDWIDGETS_ALGORITHMHINTSTRATEGY_H
+#pragma once
 
 #include "MantidAPI/AlgorithmManager.h"
 #include "MantidAPI/IAlgorithm.h"
@@ -57,5 +56,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTID_MANTIDWIDGETS_ALGORITHMHINTSTRATEGY_H */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmHistoryWindow.h b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmHistoryWindow.h
index 5aa702ae7c0c177570c4a12bbd32819e24d9e76b..67ea1b360a9007a90e05db67b2f24fe2619610bf 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmHistoryWindow.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmHistoryWindow.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef ALGORITHMHISTORYWINDOW_H
-#define ALGORITHMHISTORYWINDOW_H
+#pragma once
 
 #include "DllOption.h"
 
@@ -217,5 +216,3 @@ private:
 
   std::vector<Mantid::Kernel::PropertyHistory_sptr> m_Histprop;
 };
-
-#endif // ALGORITHMHISTORYWINDOW_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmInputHistory.h b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmInputHistory.h
index c74629fb7e654ecad491d6f6672a7f74f33e5927..5392636f81c26e87b1e4f5faa3c627fe007de1cb 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmInputHistory.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmInputHistory.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_ALGORITHMINPUTHISTORY_H_
-#define MANTIDQT_API_ALGORITHMINPUTHISTORY_H_
+#pragma once
 
 //----------------------------------
 // Includes
@@ -103,5 +102,3 @@ EXTERN_MANTIDQT_COMMON template class EXPORT_OPT_MANTIDQT_COMMON
     Mantid::Kernel::SingletonHolder<MantidQt::API::AlgorithmInputHistoryImpl>;
 }
 } // namespace Mantid
-
-#endif // ALGORITHMINPUTHISTORY_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressDialogPresenter.h b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressDialogPresenter.h
index 88af1ed6d5a6789d650b15f7ceae07295c0bf6d8..de578ca0903a5f013ebda568a443eeb87a6fda8f 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressDialogPresenter.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressDialogPresenter.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef ALGORITHMPROGRESSDIALOGPRESENTER_H
-#define ALGORITHMPROGRESSDIALOGPRESENTER_H
+#pragma once
 
 #include "MantidAPI/IAlgorithm.h"
 #include "MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressModel.h"
@@ -52,5 +51,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // ALGORITHMPROGRESSDIALOGPRESENTER_H
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressDialogWidget.h b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressDialogWidget.h
index a8694ee6143591f3dc35774372757f17a531bf98..8cd67431d110370756e6123d4b78e444137b7edd 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressDialogWidget.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressDialogWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_ALGORITHMPROGRESSDIALOGWIDGET_H
-#define MANTID_MANTIDWIDGETS_ALGORITHMPROGRESSDIALOGWIDGET_H
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressDialogPresenter.h"
@@ -74,5 +73,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // ALGORITHMPROGRESSDIALOGWIDGET_H
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressModel.h b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressModel.h
index 9c03008cc7802e0ab351898255c9baa24f031425..3060475f239b20dae4b51a128fb2dd2d563e41fa 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressModel.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressModel.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef ALGORITHMPROGRESSMODEL_H
-#define ALGORITHMPROGRESSMODEL_H
+#pragma once
 
 #include "MantidAPI/AlgorithmObserver.h"
 #include "MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressPresenterBase.h"
@@ -65,5 +64,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // ALGORITHMPROGRESSMODEL_H
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressPresenter.h b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressPresenter.h
index 33251176641caaf40737b41c60e5bd361135dc06..d46ef28390632306784afd5e5b6fc3fed0edce2f 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressPresenter.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressPresenter.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef ALGORITHMPROGRESSPRESENTER_H
-#define ALGORITHMPROGRESSPRESENTER_H
+#pragma once
 
 #include "MantidKernel/Timer.h"
 #include "MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressModel.h"
@@ -61,5 +60,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // ALGORITHMPROGRESSPRESENTER_H
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressPresenterBase.h b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressPresenterBase.h
index 785e30e7552656f30556839434103fc5932fb3a1..e9c144f268ebd85640af5a9b2af7cc940d0dcb68 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressPresenterBase.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressPresenterBase.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef ALGORITHMPROGRESSPRESENTERBASE_H
-#define ALGORITHMPROGRESSPRESENTERBASE_H
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 
@@ -59,5 +58,3 @@ signals:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // ALGORITHMPROGRESSPRESENTERBASE_H
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressWidget.h b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressWidget.h
index 7cb0c7412941e3afdaa82b243ae7b4d9f8af8bf6..15e799aa51e9164c8dd7d52f0bfa87e636463cff 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressWidget.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef ALGORITHMPROGRESSWIDGET_H
-#define ALGORITHMPROGRESSWIDGET_H
+#pragma once
 //----------------------------------
 // Includes
 //----------------------------------
@@ -71,5 +70,4 @@ private:
 };
 
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // ALGORITHMPROGRESSWIDGET_H
\ No newline at end of file
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/IAlgorithmProgressDialogWidget.h b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/IAlgorithmProgressDialogWidget.h
index f8bd9355bb0fd24c76a936d7a0d66636cbd1a6d9..0fe86d94940a463bc4ad8c32c73d51b6b8bcd70a 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/IAlgorithmProgressDialogWidget.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/IAlgorithmProgressDialogWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_IALGORITHMPROGRESSDIALOGWIDGET_H
-#define MANTID_MANTIDWIDGETS_IALGORITHMPROGRESSDIALOGWIDGET_H
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 
@@ -34,5 +33,3 @@ public:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // IALGORITHMPROGRESSDIALOGWIDGET_H
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/IAlgorithmProgressWidget.h b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/IAlgorithmProgressWidget.h
index de43247906d4d4fa3238cb17438f61a60de23b86..11ffb47139b4ef47093399a09b51bd159a0bae0b 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/IAlgorithmProgressWidget.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmProgress/IAlgorithmProgressWidget.h
@@ -1,5 +1,4 @@
-#ifndef IALGORITHMPROGRESSWIDGET_H
-#define IALGORITHMPROGRESSWIDGET_H
+#pragma once
 class QString;
 
 namespace MantidQt {
@@ -17,5 +16,3 @@ public:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // IALGORITHMPROGRESSWIDGET_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmPropertiesWidget.h b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmPropertiesWidget.h
index 0d3c5952eb0899cf4e33184222bd90f78d265f8f..21a36ed4810b714441df90a2d8dfc54113e83a7f 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmPropertiesWidget.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmPropertiesWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_API_ALGORITHMPROPERTIESWIDGET_H_
-#define MANTID_API_ALGORITHMPROPERTIESWIDGET_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidAPI/IAlgorithm.h"
@@ -111,5 +110,3 @@ private:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif /* MANTID_API_ALGORITHMPROPERTIESWIDGET_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmRunner.h b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmRunner.h
index e529bccc99e6da9389bb1c4ae5efbf1fc83ce079..c0b113e4337e61f578eea7291c801f6b6345c13b 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmRunner.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmRunner.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_API_ALGORITHMRUNNER_H_
-#define MANTID_API_ALGORITHMRUNNER_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidAPI/Algorithm.h"
@@ -77,5 +76,3 @@ protected:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif /* MANTID_API_ALGORITHMRUNNER_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmSelectorWidget.h b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmSelectorWidget.h
index c29de6306050cb3a1c71f71c6b523625703c9937..3b975b8cd3ada02a04bd56210be6ba759d3cd2a1 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmSelectorWidget.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/AlgorithmSelectorWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_ALGORITHMSELECTORWIDGET_H_
-#define MANTID_MANTIDWIDGETS_ALGORITHMSELECTORWIDGET_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidAPI/AlgorithmFactory.h"
@@ -149,5 +148,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTID_MANTIDWIDGETS_ALGORITHMSELECTORWIDGET_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/AlternateCSPythonLexer.h b/qt/widgets/common/inc/MantidQtWidgets/Common/AlternateCSPythonLexer.h
index a7e91bb2ac7b821de4dfacc51ff63defc8fea922..083081670acc1273d3f62a5da4e47e2aadef0603 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/AlternateCSPythonLexer.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/AlternateCSPythonLexer.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_WIDGETS_ALTERNATECSPYTHONLEXER_H
-#define MANTIDQT_WIDGETS_ALTERNATECSPYTHONLEXER_H
+#pragma once
 
 #include <Qsci/qscilexerpython.h>
 
@@ -23,5 +22,3 @@ public:
 private:
   QFont m_font;
 };
-
-#endif // MANTIDQT_WIDGETS_ALTERNATECSPYTHONLEXER_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/BaseDecoder.h b/qt/widgets/common/inc/MantidQtWidgets/Common/BaseDecoder.h
index f1ee37139b1ef24e1bf0ea4e86e2c67102ffa72d..6881b81102c4c5dd157bf640b6eedff47440e5df 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/BaseDecoder.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/BaseDecoder.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_ABSTRACTDECODER_H_
-#define MANTIDQT_API_ABSTRACTDECODER_H_
+#pragma once
 
 #include <QList>
 #include <QMap>
@@ -26,5 +25,3 @@ public:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif /* MANTIDQT_API_ABSTRACTDECODER_H_ */
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/BaseEncoder.h b/qt/widgets/common/inc/MantidQtWidgets/Common/BaseEncoder.h
index d731d15fbe29b6716ea98dfd7e6a617d5e23991d..f579e662d6ad69000e67faa2d10d64ba67c46635 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/BaseEncoder.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/BaseEncoder.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_ABSTRACTENCODER_H_
-#define MANTIDQT_API_ABSTRACTENCODER_H_
+#pragma once
 
 #include <QList>
 #include <QMap>
@@ -26,5 +25,3 @@ public:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif /* MANTIDQT_API_ABSTRACTENCODER_H_ */
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/AssertOrThrow.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/AssertOrThrow.h
index 5b4156e323b0d176b44cd61fe0b7bf15749f1349..024aa39633897d094b896619b487931331155619 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/AssertOrThrow.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/AssertOrThrow.h
@@ -8,8 +8,7 @@
 See the developer documentation for Batch Widget at
 developer.mantidproject.org/BatchWidget/index.html
 */
-#ifndef MANTIDQTMANTIDWIDGETS_ASSERTORTHROW_H_
-#define MANTIDQTMANTIDWIDGETS_ASSERTORTHROW_H_
+#pragma once
 #include <stdexcept>
 #include <string>
 
@@ -17,5 +16,3 @@ inline void assertOrThrow(bool condition, std::string const &message) {
   if (!condition)
     throw std::runtime_error(message);
 }
-
-#endif
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/BuildSubtreeItems.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/BuildSubtreeItems.h
index c3baea53faf8e5542c1c69869f014e241bd75969..fef33a391cabc6c71b7d7dec85cd83a3ed22b66d 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/BuildSubtreeItems.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/BuildSubtreeItems.h
@@ -8,8 +8,7 @@
 See the developer documentation for Batch Widget at
 developer.mantidproject.org/BatchWidget/index.html
 */
-#ifndef MANTIDQTMANTIDWIDGETS_BUILDSUBTREE_H_
-#define MANTIDQTMANTIDWIDGETS_BUILDSUBTREE_H_
+#pragma once
 #include "MantidQtWidgets/Common/Batch/AssertOrThrow.h"
 #include "MantidQtWidgets/Common/Batch/QtStandardItemTreeAdapter.h"
 #include "MantidQtWidgets/Common/Batch/RowLocationAdapter.h"
@@ -42,5 +41,4 @@ private:
 
 } // namespace Batch
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/Cell.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/Cell.h
index affca5af6ad8cbd8af8d38448a3217a37cba32d8..db3265d6a8d6f2ae4a90dc9a5531575820914d1b 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/Cell.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/Cell.h
@@ -8,8 +8,7 @@
 See the developer documentation for Batch Widget at
 developer.mantidproject.org/BatchWidget/index.html
 */
-#ifndef MANTIDQTMANTIDWIDGETS_CELL_H_
-#define MANTIDQTMANTIDWIDGETS_CELL_H_
+#pragma once
 #include "MantidQtWidgets/Common/DllOption.h"
 #include <string>
 #include <vector>
@@ -85,5 +84,4 @@ paddedCellsToWidth(std::vector<Cell> const &cells, Cell const &paddingCell,
                    int paddedWidth);
 } // namespace Batch
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTMANTIDWIDGETS_CELL_H_
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/CellDelegate.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/CellDelegate.h
index e61835aa9a13ef3afd42dcbeead2ba0352513f7e..1a15207a44933a6ab5c4977d1c979cf704bbf0d2 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/CellDelegate.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/CellDelegate.h
@@ -8,8 +8,7 @@
 See the developer documentation for Batch Widget at
 developer.mantidproject.org/BatchWidget/index.html
 */
-#ifndef MANTIDQTMANTIDWIDGETS_CELLDELEGATE_H_
-#define MANTIDQTMANTIDWIDGETS_CELLDELEGATE_H_
+#pragma once
 #include "MantidQtWidgets/Common/Batch/FilteredTreeModel.h"
 #include <QStandardItemModel>
 #include <QStyledItemDelegate>
@@ -33,5 +32,4 @@ private:
 };
 } // namespace Batch
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTMANTIDWIDGETS_CELLDELEGATE_H_
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/CellStandardItem.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/CellStandardItem.h
index 27eb6dcfdcb975f94cba11cab3ee8ec55a218909..85ae9cb5cbf76276062cac8a5323343356be88e3 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/CellStandardItem.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/CellStandardItem.h
@@ -8,8 +8,7 @@
 See the developer documentation for Batch Widget at
 developer.mantidproject.org/BatchWidget/index.html
 */
-#ifndef MANTIDQTMANTIDWIDGETS_CELLSTANDARDITEM_H_
-#define MANTIDQTMANTIDWIDGETS_CELLSTANDARDITEM_H_
+#pragma once
 #include "MantidQtWidgets/Common/Batch/Cell.h"
 #include <QColor>
 #include <QStandardItem>
@@ -46,5 +45,4 @@ void applyCellPropertiesToItem(Cell const &cell, QStandardItem &item);
 Cell extractCellPropertiesFromItem(QStandardItem const &item);
 } // namespace Batch
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTMANTIDWIDGETS_CELLSTANDARDITEM_H_
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/ExtractSubtrees.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/ExtractSubtrees.h
index 30e8d04dc37640d784e7c40a29ec4d7af6bab59e..b7f36a140aa4f1d586a2ed7a8241329f5d9d9439 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/ExtractSubtrees.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/ExtractSubtrees.h
@@ -8,8 +8,7 @@
 See the developer documentation for Batch Widget at
 developer.mantidproject.org/BatchWidget/index.html
 */
-#ifndef MANTIDQTMANTIDWIDGETS_EXTRACTSUBTREES_H_
-#define MANTIDQTMANTIDWIDGETS_EXTRACTSUBTREES_H_
+#pragma once
 #include "MantidQtWidgets/Common/Batch/AssertOrThrow.h"
 #include "MantidQtWidgets/Common/Batch/Row.h"
 #include "MantidQtWidgets/Common/Batch/RowLocation.h"
@@ -45,5 +44,4 @@ private:
 
 } // namespace Batch
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/FilteredTreeModel.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/FilteredTreeModel.h
index c6706efd287ea7961d0a3d34a5566ce8e61f4043..12a2a312f89e28676ddb1fe435f165e2acd90629 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/FilteredTreeModel.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/FilteredTreeModel.h
@@ -8,8 +8,7 @@
 See the developer documentation for Batch Widget at
 developer.mantidproject.org/BatchWidget/index.html
 */
-#ifndef MANTIDQTMANTIDWIDGETS_FILTEREDTREEMODEL_H_
-#define MANTIDQTMANTIDWIDGETS_FILTEREDTREEMODEL_H_
+#pragma once
 #include "MantidQtWidgets/Common/Batch/RowLocation.h"
 #include "MantidQtWidgets/Common/Batch/RowLocationAdapter.h"
 #include "MantidQtWidgets/Common/Batch/RowPredicate.h"
@@ -38,5 +37,4 @@ private:
 };
 } // namespace Batch
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTMANTIDWIDGETS_FILTEREDTREEMODEL_H_
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/FindSubtreeRoots.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/FindSubtreeRoots.h
index 1f59eada915196aa841563161399a416b04e8005..d933bb9994506e3ac1838e6100f172777786019d 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/FindSubtreeRoots.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/FindSubtreeRoots.h
@@ -8,8 +8,7 @@
 See the developer documentation for Batch Widget at
 developer.mantidproject.org/BatchWidget/index.html
 */
-#ifndef MANTIDQTMANTIDWIDGETS_FINDSUBTREEROOTS_H_
-#define MANTIDQTMANTIDWIDGETS_FINDSUBTREEROOTS_H_
+#pragma once
 #include "MantidQtWidgets/Common/Batch/AssertOrThrow.h"
 #include "MantidQtWidgets/Common/Batch/RowLocation.h"
 #include "MantidQtWidgets/Common/DllOption.h"
@@ -32,5 +31,4 @@ private:
 
 } // namespace Batch
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/IJobTreeView.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/IJobTreeView.h
index c30e087e073b24320bc9269d54ee5db79d78d24b..73be371198e410fd28f028e9558abbf5ddf8c872 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/IJobTreeView.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/IJobTreeView.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_IJOBTREEVIEW_H_
-#define MANTIDQTMANTIDWIDGETS_IJOBTREEVIEW_H_
+#pragma once
 #include "MantidQtWidgets/Common/Batch/Cell.h"
 #include "MantidQtWidgets/Common/Batch/Row.h"
 #include "MantidQtWidgets/Common/Batch/RowLocation.h"
@@ -104,5 +103,4 @@ public:
 };
 } // namespace Batch
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTMANTIDWIDGETS_IJOBTREEVIEW_H_
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/JobTreeView.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/JobTreeView.h
index 50de63f20613dcc90b327abd102b6f5a9b400b9e..21573c68964d23a0640dd22beddfdb433274ce8d 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/JobTreeView.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/JobTreeView.h
@@ -8,8 +8,7 @@
 See the developer documentation for Batch Widget at
 developer.mantidproject.org/BatchWidget/index.html
 */
-#ifndef MANTIDQTMANTIDWIDGETS_JOBTREEVIEW_H_
-#define MANTIDQTMANTIDWIDGETS_JOBTREEVIEW_H_
+#pragma once
 #include "MantidQtWidgets/Common/Batch/Cell.h"
 #include "MantidQtWidgets/Common/Batch/ExtractSubtrees.h"
 #include "MantidQtWidgets/Common/Batch/FilteredTreeModel.h"
@@ -179,5 +178,4 @@ private:
 };
 } // namespace Batch
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTMANTIDWIDGETS_JOBTREEVIEW_H_
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/JobTreeViewSignalAdapter.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/JobTreeViewSignalAdapter.h
index 64eb32e58b71e6648b5edaf2784ef918bb4e3439..15d93266aeab78269e56709a8ea1d288f04ec69d 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/JobTreeViewSignalAdapter.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/JobTreeViewSignalAdapter.h
@@ -8,8 +8,7 @@
 See the developer documentation for Batch Widget at
 developer.mantidproject.org/BatchWidget/index.html
 */
-#ifndef MANTIDQTMANTIDWIDGETS_JOBTREEVIEWSIGNALADAPTER_H_
-#define MANTIDQTMANTIDWIDGETS_JOBTREEVIEWSIGNALADAPTER_H_
+#pragma once
 #include "MantidQtWidgets/Common/Batch/JobTreeView.h"
 #include "MantidQtWidgets/Common/DllOption.h"
 namespace MantidQt {
@@ -57,5 +56,4 @@ signals:
 };
 } // namespace Batch
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTMANTIDWIDGETS_JOBTREEVIEWSIGNALADAPTER_H_
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/MockJobTreeView.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/MockJobTreeView.h
index f62c14aeaed6043731d001bf501b56c2b20b0933..d529e9e3f53e04dd201aee15438cf9549fa4cb81 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/MockJobTreeView.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/MockJobTreeView.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_MOCKJOBTREEVIEW_H_
-#define MANTIDQTMANTIDWIDGETS_MOCKJOBTREEVIEW_H_
+#pragma once
 #include "MantidKernel/WarningSuppressions.h"
 #include "MantidQtWidgets/Common/Batch/IJobTreeView.h"
 #include <gmock/gmock.h>
@@ -93,5 +92,4 @@ private:
 GNU_DIAG_ON_SUGGEST_OVERRIDE
 } // namespace Batch
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTMANTIDWIDGETS_MOCKJOBTREEVIEW_H_
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/QtBasicNavigation.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/QtBasicNavigation.h
index 6794802f2bddb3e424d7ebeab67b63f2e4c012e3..324d37a2945d6f250641729ae72d893335c6c53c 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/QtBasicNavigation.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/QtBasicNavigation.h
@@ -8,8 +8,7 @@
 See the developer documentation for Batch Widget at
 developer.mantidproject.org/BatchWidget/index.html
 */
-#ifndef MANTIDQTMANTIDWIDGETS_QTBASICNAVIGATION_H_
-#define MANTIDQTMANTIDWIDGETS_QTBASICNAVIGATION_H_
+#pragma once
 #include <QModelIndex>
 
 namespace MantidQt {
@@ -30,5 +29,4 @@ bool hasRowBelow(QModelIndex const &index);
 bool areOnSameRow(QModelIndex const &a, QModelIndex const &b);
 } // namespace Batch
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTMANTIDWIDGETS_QTBASICNAVIGATION_H_
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/QtStandardItemTreeAdapter.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/QtStandardItemTreeAdapter.h
index cd97c4b6150270db55e0e5e9d84e58c4830dd067..de5542aa0c21a8fc5ce57dbd1c2d1d7e4e94e509 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/QtStandardItemTreeAdapter.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/QtStandardItemTreeAdapter.h
@@ -8,8 +8,7 @@
 See the developer documentation for Batch Widget at
 developer.mantidproject.org/BatchWidget/index.html
 */
-#ifndef MANTIDQTMANTIDWIDGETS_TREEITEMMODELADAPTER_H_
-#define MANTIDQTMANTIDWIDGETS_TREEITEMMODELADAPTER_H_
+#pragma once
 #include "MantidQtWidgets/Common/Batch/Row.h"
 #include "MantidQtWidgets/Common/Batch/StrictQModelIndices.h"
 #include "MantidQtWidgets/Common/DllOption.h"
@@ -90,5 +89,4 @@ modelItemFromIndex(QStandardItemModel const &model,
                    QModelIndexForMainModel const &index);
 } // namespace Batch
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTMANTIDWIDGETS_TREEITEMMODELADAPTER_H_
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/QtTreeCursorNavigation.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/QtTreeCursorNavigation.h
index 06a6dd0a669786214d59f338951509e5e841d58e..5b7e0114308a17879402ca67d21faee54d59bd3a 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/QtTreeCursorNavigation.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/QtTreeCursorNavigation.h
@@ -8,8 +8,7 @@
 See the developer documentation for Batch Widget at
 developer.mantidproject.org/BatchWidget/index.html
 */
-#ifndef MANTIDQTMANTIDWIDGETS_QTTREECURSORNAVIGATION_H_
-#define MANTIDQTMANTIDWIDGETS_QTTREECURSORNAVIGATION_H_
+#pragma once
 #include <QModelIndex>
 #include <utility>
 namespace MantidQt {
@@ -44,5 +43,4 @@ private:
 };
 } // namespace Batch
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTMANTIDWIDGETS_QTTREECURSORNAVIGATION_H_
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/Row.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/Row.h
index 4dc57320bd999c31f9bdfb6bb8b16f984bb20c6b..49d01fb9c93102a5a7a0e9898d3cc970e7670513 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/Row.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/Row.h
@@ -8,8 +8,7 @@
 See the developer documentation for Batch Widget at
 developer.mantidproject.org/BatchWidget/index.html
 */
-#ifndef MANTIDQTMANTIDWIDGETS_ROW_H_
-#define MANTIDQTMANTIDWIDGETS_ROW_H_
+#pragma once
 #include "MantidQtWidgets/Common/Batch/Cell.h"
 #include "MantidQtWidgets/Common/Batch/RowLocation.h"
 #include "MantidQtWidgets/Common/DllOption.h"
@@ -46,5 +45,4 @@ EXPORT_OPT_MANTIDQT_COMMON bool operator>=(Row const &lhs, Row const &rhs);
 
 } // namespace Batch
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/RowLocation.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/RowLocation.h
index 66dcd7992d4bb258115dc4f6b63346c4ae6406d9..2e1c02e58520d6c6313bc10e17a393f8daabb528 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/RowLocation.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/RowLocation.h
@@ -8,8 +8,7 @@
 See the developer documentation for Batch Widget at
 developer.mantidproject.org/BatchWidget/index.html
 */
-#ifndef MANTIDQTMANTIDWIDGETS_ROWLOCATION_H_
-#define MANTIDQTMANTIDWIDGETS_ROWLOCATION_H_
+#pragma once
 #include "MantidQtWidgets/Common/DllOption.h"
 #include <boost/optional.hpp>
 #include <ostream>
@@ -54,5 +53,4 @@ pathsSameUntilDepth(int depth, RowLocation const &locationA,
 
 } // namespace Batch
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/RowLocationAdapter.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/RowLocationAdapter.h
index f957571cc6fd7eaa9ddd98e0e417efb429fdbeae..430425983876dd3a3664f20d1c2495b22b5f44fc 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/RowLocationAdapter.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/RowLocationAdapter.h
@@ -8,8 +8,7 @@
 See the developer documentation for Batch Widget at
 developer.mantidproject.org/BatchWidget/index.html
 */
-#ifndef MANTIDQTMANTIDWIDGETS_ROWLOCATIONADAPTER_H_
-#define MANTIDQTMANTIDWIDGETS_ROWLOCATIONADAPTER_H_
+#pragma once
 #include "MantidQtWidgets/Common/Batch/RowLocation.h"
 #include "MantidQtWidgets/Common/Batch/StrictQModelIndices.h"
 #include "MantidQtWidgets/Common/DllOption.h"
@@ -35,5 +34,4 @@ private:
 };
 } // namespace Batch
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTMANTIDWIDGETS_ROWLOCATIONADAPTER_H_
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/RowPredicate.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/RowPredicate.h
index e51f65e753869e5d07de4b6b0cd066b7ef8fcff9..3724e4c1ae4f3c52dfee620b838edd5ed5696058 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/RowPredicate.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/RowPredicate.h
@@ -8,8 +8,7 @@
 See the developer documentation for Batch Widget at
 developer.mantidproject.org/BatchWidget/index.html
 */
-#ifndef MANTIDQTMANTIDWIDGETS_ROWPREDICATE_H_
-#define MANTIDQTMANTIDWIDGETS_ROWPREDICATE_H_
+#pragma once
 
 #include "MantidQtWidgets/Common/Batch/RowLocation.h"
 #include <memory>
@@ -47,5 +46,4 @@ std::unique_ptr<RowPredicate> makeFilterFromLambda(Predicate predicate) {
 }
 } // namespace Batch
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTMANTIDWIDGETS_ROWPREDICATE_H_
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/StrictQModelIndices.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/StrictQModelIndices.h
index 9fe09c3cfb4c8da646a8550fe395214276f67dc4..e41c151f0f17b8d02d39d74b68925f6a044d514b 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/StrictQModelIndices.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/StrictQModelIndices.h
@@ -8,8 +8,7 @@
 See the developer documentation for Batch Widget at
 developer.mantidproject.org/BatchWidget/index.html
 */
-#ifndef MANTIDQTMANTIDWIDGETS_STRICTQMODELINDICES_H_
-#define MANTIDQTMANTIDWIDGETS_STRICTQMODELINDICES_H_
+#pragma once
 #include "MantidQtWidgets/Common/Batch/AssertOrThrow.h"
 #include "MantidQtWidgets/Common/DllOption.h"
 #include <QModelIndex>
@@ -99,5 +98,4 @@ inline QModelIndexForMainModel fromMainModel(QModelIndex const &mainModelIndex,
 }
 } // namespace Batch
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTMANTIDWIDGETS_STRICTQMODELINDICES_H_
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/Subtree.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/Subtree.h
index 76d86f84c9816dcfecee2d25b27f3a4670c4ccf4..a389b49f1cb86534828d392158d1ea13a8c39359 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/Subtree.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/Subtree.h
@@ -8,8 +8,7 @@
 See the developer documentation for Batch Widget at
 developer.mantidproject.org/BatchWidget/index.html
 */
-#ifndef MANTIDQTMANTIDWIDGETS_SUBTREE_H_
-#define MANTIDQTMANTIDWIDGETS_SUBTREE_H_
+#pragma once
 #include "MantidQtWidgets/Common/Batch/Row.h"
 
 namespace MantidQt {
@@ -77,5 +76,4 @@ bool allSubtreeRootsShareAParentAndAllSubtreeNodesAreConnected(
 }
 } // namespace Batch
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTMANTIDWIDGETS_SUBTREE_H_
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/equal.hpp b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/equal.hpp
index 1210d48217f9eb069acf04d8aa48e57529b6103f..c99d534dbe14537f3583ece2458063103d218041 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/equal.hpp
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Batch/equal.hpp
@@ -10,8 +10,7 @@
 /// \brief Test ranges to if they are equal
 /// \author Marshall Clow
 
-#ifndef BOOST_ALGORITHM_EQUAL_HPP
-#define BOOST_ALGORITHM_EQUAL_HPP
+#pragma once
 
 #include <algorithm>    // for std::equal
 #include <iterator>
@@ -94,6 +93,4 @@ bool equal ( InputIterator1 first1, InputIterator1 last1,
 //  There are already range-based versions of these.
 
 }} // namespace boost and algorithm
-
-#endif // BOOST_ALGORITHM_EQUAL_HPP
 // clang-format on
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/BatchAlgorithmRunner.h b/qt/widgets/common/inc/MantidQtWidgets/Common/BatchAlgorithmRunner.h
index bfcc65c1e2cb4cf2d11c0b0c64805eaaaf0417f5..2f25ac6638895cee59dc226370759b262961af05 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/BatchAlgorithmRunner.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/BatchAlgorithmRunner.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_API_BATCHALGORITHMRUNNER_H_
-#define MANTID_API_BATCHALGORITHMRUNNER_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidAPI/Algorithm.h"
@@ -206,5 +205,3 @@ private:
 };
 } // namespace API
 } // namespace MantidQt
-
-#endif /* MANTID_API_BATCHALGORITHMRUNNER_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/BoolPropertyWidget.h b/qt/widgets/common/inc/MantidQtWidgets/Common/BoolPropertyWidget.h
index f66e8799f2b29e76fe2470736fe1f634117b31a3..cf93277be57d3c3919392814f7cff5a2111110b3 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/BoolPropertyWidget.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/BoolPropertyWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_API_BOOLPROPERTYWIDGET_H_
-#define MANTID_API_BOOLPROPERTYWIDGET_H_
+#pragma once
 
 #include "MantidKernel/PropertyWithValue.h"
 #include "MantidKernel/System.h"
@@ -41,5 +40,3 @@ protected:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif /* MANTID_API_BOOLPROPERTYWIDGET_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/CatalogHelper.h b/qt/widgets/common/inc/MantidQtWidgets/Common/CatalogHelper.h
index c021624afbc0fcaa5c9e2fde1969f8ebc7511956..02f9ca87a4e74cc1285ded272c9258f309a044b2 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/CatalogHelper.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/CatalogHelper.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTWIDGETS_CATALOGHELPER_H_
-#define MANTIDQTWIDGETS_CATALOGHELPER_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidAPI/AlgorithmManager.h"
@@ -66,5 +65,4 @@ private:
       const std::map<std::string, std::string> &userInputFields);
 };
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTWIDGETS_CATALOGHELPER_H_
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/CatalogSearch.h b/qt/widgets/common/inc/MantidQtWidgets/Common/CatalogSearch.h
index be90ee839ec771cb6ee257491d41094b2cebf640..98bc1f6ee4ccc045399f4adfeae05bf67346e463 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/CatalogSearch.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/CatalogSearch.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTWIDGETS_CATALOGSEARCH_H_
-#define MANTIDQTWIDGETS_CATALOGSEARCH_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidAPI/ITableWorkspace.h"
@@ -201,5 +200,4 @@ private:
   void correctedToolTip(std::string toolTip, QLabel *label);
 };
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTWIDGETS_CATALOGSEARCH_H_
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/CatalogSelector.h b/qt/widgets/common/inc/MantidQtWidgets/Common/CatalogSelector.h
index bdb875c425b6cf6741b727092a2d41e3ba81975f..8f2d7ce7f7d325cda54c2c2e32e2242227cdf5e6 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/CatalogSelector.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/CatalogSelector.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTWIDGETS_CATALOGSELECTOR_H_
-#define MANTIDQTWIDGETS_CATALOGSELECTOR_H_
+#pragma once
 
 #include "DllOption.h"
 #include "ui_CatalogSelector.h"
@@ -38,5 +37,3 @@ protected:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQTWIDGETS_CATALOGSELECTOR_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/CheckboxHeader.h b/qt/widgets/common/inc/MantidQtWidgets/Common/CheckboxHeader.h
index 4ccdb9cb24fd42efdc2e339db741339370753e44..810dc3aec0e8d9a554e22aeced0e733f609738aa 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/CheckboxHeader.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/CheckboxHeader.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTWIDGETS_CHECKBOXHEADER_H_
-#define MANTIDQTWIDGETS_CHECKBOXHEADER_H_
+#pragma once
 
 #include "DllOption.h"
 
@@ -50,5 +49,4 @@ private:
   bool m_checked;
 };
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTWIDGETS_CHECKBOXHEADER_H_
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Configurable.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Configurable.h
index 81a770f54b1b131e581b2ce204f01e74f9cb661c..b4eedca4be934557819edd28f8d1f76a87adb1d3 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Configurable.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Configurable.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGETS_CONFIGURABLE_H
-#define MANTIDQT_MANTIDWIDGETS_CONFIGURABLE_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DllOption.h"
 
@@ -30,5 +29,3 @@ public:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQT_MANTIDWIDGETS_CONFIGURABLE_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/ConvolutionFunctionModel.h b/qt/widgets/common/inc/MantidQtWidgets/Common/ConvolutionFunctionModel.h
index 0785824b87ec74fa1b14df0d09977fdd05c54e14..b634a7b913e6a34713c1931f912fe562742bedbb 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/ConvolutionFunctionModel.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/ConvolutionFunctionModel.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDWIDGETS_CONVOLUTIONFUNCTIONMODEL_H_
-#define MANTIDWIDGETS_CONVOLUTIONFUNCTIONMODEL_H_
+#pragma once
 
 #include "DllOption.h"
 #include "FunctionModel.h"
@@ -78,5 +77,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDWIDGETS_CONVOLUTIONFUNCTIONMODEL_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/AbstractTreeModel.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/AbstractTreeModel.h
index 0ba820498604b49003caa6e5270ecb01fbefc563..7ce7ad3c48a006f71e099860d7d47a9e92dd51b7 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/AbstractTreeModel.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/AbstractTreeModel.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_ABSTRACTDATAPROCESSORTREEMODEL_H_
-#define MANTIDQTMANTIDWIDGETS_ABSTRACTDATAPROCESSORTREEMODEL_H_
+#pragma once
 
 #include "MantidAPI/ITableWorkspace_fwd.h"
 #include "MantidQtWidgets/Common/DataProcessorUI/WhiteList.h"
@@ -76,5 +75,3 @@ protected:
 } // namespace DataProcessor
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTIDQTMANTIDWIDGETS_ABSTRACTDATAPROCESSORTREEMODEL_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/AppendGroupCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/AppendGroupCommand.h
index 2d8054bc14d5f5b8e3c2ae4af426cc0d379de6a3..5a389814507e9affcbce0a6f92d8ffb84db2a192 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/AppendGroupCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/AppendGroupCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORAPPENDGROUPCOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORAPPENDGROUPCOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 #include "MantidQtWidgets/Common/DataProcessorUI/DataProcessorPresenter.h"
@@ -40,5 +39,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORAPPENDGROUPCOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/AppendRowCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/AppendRowCommand.h
index dc6da7c4b1b8a64afec16f3493648e23c85fa3ae..0f0b5e999899ee86419e7a536016a8997f61bffe 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/AppendRowCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/AppendRowCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORAPPENDROWCOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORAPPENDROWCOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 #include "MantidQtWidgets/Common/DataProcessorUI/DataProcessorPresenter.h"
@@ -40,5 +39,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORAPPENDROWCOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ClearSelectedCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ClearSelectedCommand.h
index 3824e6ad455d2cc010f4bf54337f601ba2e1a001..33b44aae880624166818335cd6bca02edfd5412a 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ClearSelectedCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ClearSelectedCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORCLEARSELECTEDCOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORCLEARSELECTEDCOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 
@@ -37,5 +36,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORCLEARSELECTEDCOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/CollapseGroupsCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/CollapseGroupsCommand.h
index 7cef41bae8f361928428b2cdd82aa18fb0c7dffe..83626497bd4ceb664c2f5835246bf88f217bbe99 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/CollapseGroupsCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/CollapseGroupsCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORCOLLAPSEGROUPSCOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORCOLLAPSEGROUPSCOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 
@@ -38,5 +37,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORCOLLAPSEGROUPSCOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/Column.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/Column.h
index 50706c801c0ca1e47729bf5796ac7df7e8d14e82..70acd9037f683e432cc2e4a16a4941b0b8315a92 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/Column.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/Column.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORCOLUMN_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORCOLUMN_H
+#pragma once
 #include "MantidQtWidgets/Common/DllOption.h"
 #include <QString>
 namespace MantidQt {
@@ -38,5 +37,4 @@ private:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTMANTIDWIDGETS_DATAPROCESSORCOLUMN_H
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/Command.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/Command.h
index 07fbd5e4a598fdd7c887b8cc22e619ca1e559d53..feca29d2f4ace02a28a6a7b970f5026cea33542d 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/Command.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/Command.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORCOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORCOMMAND_H
+#pragma once
 
 #include <memory>
 #include <vector>
@@ -53,5 +52,4 @@ protected:
 using Command_uptr = std::unique_ptr<Command>;
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORCOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/CommandBase.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/CommandBase.h
index 4a9376b605e9ddb1155f78ffaab4c197e8f8d284..8d2ef2b05b4c595c8e72cba4bc0d3af139b6d13e 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/CommandBase.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/CommandBase.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORCOMMANDBASE_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORCOMMANDBASE_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/Command.h"
 #include "MantidQtWidgets/Common/DataProcessorUI/DataProcessorPresenter.h"
@@ -36,5 +35,4 @@ protected:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORCOMMANDBASE_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ConstColumnIterator.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ConstColumnIterator.h
index f8e15a0690cdf3588ec32be1f4e28b2a4ad83c5a..a5b68242bbb93fa43925d2566a0bb2965d114e0b 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ConstColumnIterator.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ConstColumnIterator.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORCONSTCOLUMNITERATOR_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORCONSTCOLUMNITERATOR_H
+#pragma once
 #include "MantidQtWidgets/Common/DataProcessorUI/Column.h"
 #include "MantidQtWidgets/Common/DllOption.h"
 #include <QString>
@@ -62,5 +61,4 @@ ConstColumnIterator EXPORT_OPT_MANTIDQT_COMMON operator-(
     ConstColumnIterator::difference_type n, const ConstColumnIterator &rhs);
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTMANTIDWIDGETS_DATAPROCESSORCONSTCOLUMNITERATOR_H
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/CopySelectedCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/CopySelectedCommand.h
index a6f5aa73ef2fdf10783ead56ed8b605056cc3bfe..78470ac1911dcd15179fa15c43dfb7182b1eb71a 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/CopySelectedCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/CopySelectedCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORCOPYSELECTEDCOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORCOPYSELECTEDCOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 
@@ -39,5 +38,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORCOPYSELECTEDCOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/CutSelectedCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/CutSelectedCommand.h
index 94ae3cffbe9bbc5a45dbedc88c3628f4ee9bfe15..5c5112e21c3b2e0bf66be174c233e971020c85a7 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/CutSelectedCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/CutSelectedCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORCUTSELECTEDCOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORCUTSELECTEDCOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 
@@ -39,5 +38,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORCUTSELECTEDCOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/DataProcessorMainPresenter.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/DataProcessorMainPresenter.h
index ab2f8043d61b9d457c0d18977f706be77a38d1b8..c7a9430eda002b3babbdd696552588189a79aa7f 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/DataProcessorMainPresenter.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/DataProcessorMainPresenter.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORMAINPRESENTER_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORMAINPRESENTER_H
+#pragma once
 
 #include "MantidKernel/System.h"
 #include "MantidQtWidgets/Common/DataProcessorUI/OptionsQMap.h"
@@ -77,5 +76,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /* MANTIDQTMANTIDWIDGETS_DATAPROCESSORMAINPRESENTER_H */
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/DataProcessorPresenter.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/DataProcessorPresenter.h
index a675d3f13e0111ce85d390abc7e662a6eb3aef23..921a24289fc53b5862a716e05feba0b72a7643dc 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/DataProcessorPresenter.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/DataProcessorPresenter.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORPRESENTER_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORPRESENTER_H
+#pragma once
 
 #include <QVariant>
 #include <map>
@@ -107,5 +106,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORPRESENTER_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/DataProcessorView.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/DataProcessorView.h
index a3130abf8325c0e9f7c8fc1b5fa2ac535735bad4..180a7bcb66e8775e752770ce8bbc132ba5822a25 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/DataProcessorView.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/DataProcessorView.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORVIEW_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORVIEW_H
+#pragma once
 
 #include "MantidKernel/System.h"
 
@@ -107,5 +106,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORVIEW_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/DeleteGroupCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/DeleteGroupCommand.h
index 752c7e66e6147517de8d8f3adf14e1141c137067..03a877a86517b6377271efadf160778b8c46b0b6 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/DeleteGroupCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/DeleteGroupCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORDELETEGROUPCOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORDELETEGROUPCOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 
@@ -38,5 +37,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORDELETEGROUPCOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/DeleteRowCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/DeleteRowCommand.h
index 944b049ef688f9b70d7f127ccc7d60172b5beb84..a6597baba1fcc3f34787279e34e89ee5082d6ee2 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/DeleteRowCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/DeleteRowCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORDELETEROWCOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORDELETEROWCOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 
@@ -35,5 +34,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORDELETEROWCOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ExpandCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ExpandCommand.h
index dd701eb71c80683632360337244562cc83738fbf..e8a9f1ebf20b8f95979824c774cd854a05359e1c 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ExpandCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ExpandCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSOREXPANDCOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSOREXPANDCOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 
@@ -40,5 +39,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSOREXPANDCOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ExpandGroupsCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ExpandGroupsCommand.h
index f5c1f7efc77c892d4a95554e0b8d23bd6e0a7dfd..25c96bcc0a2dc40c804878233de419d564735ea1 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ExpandGroupsCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ExpandGroupsCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSOREXPANDGROUPSCOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSOREXPANDGROUPSCOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 
@@ -38,5 +37,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSOREXPANDGROUPSCOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ExportTableCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ExportTableCommand.h
index c16703d038c96edd461f2c1bc699e738245e51d6..f48736e8f09d48a7f6ce905483246060e017c456 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ExportTableCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ExportTableCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSOREXPORTTABLECOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSOREXPORTTABLECOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 
@@ -40,5 +39,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSOREXPORTTABLECOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GenerateNotebook.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GenerateNotebook.h
index de72e0914c3ba67780fa6fb2257ecb5dffd4392d..aa54d27cab6f4dc95bbc2544bb2b1d074b97a7ad 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GenerateNotebook.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GenerateNotebook.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORGENERATENOTEBOOK_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORGENERATENOTEBOOK_H
+#pragma once
 
 /** @class GenerateNotebook
 
@@ -110,5 +109,4 @@ private:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTMANTIDWIDGETS_DATAPROCESSORGENERATENOTEBOOK_H
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GenericDataProcessorPresenter.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GenericDataProcessorPresenter.h
index 3cc1839660809fa740dbe22737f0c10ecdc4c535..1e876c3a7ccd04bdf64e1b273f827bed57aea6fb 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GenericDataProcessorPresenter.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GenericDataProcessorPresenter.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_GENERICDATAPROCESSORPRESENTER_H
-#define MANTIDQTMANTIDWIDGETS_GENERICDATAPROCESSORPRESENTER_H
+#pragma once
 #include "MantidAPI/IAlgorithm_fwd.h"
 #include "MantidAPI/ITableWorkspace_fwd.h"
 #include "MantidQtWidgets/Common/DataProcessorUI/Command.h"
@@ -393,5 +392,4 @@ private:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_GENERICDATAPROCESSORPRESENTER_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GenericDataProcessorPresenterFactory.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GenericDataProcessorPresenterFactory.h
index 11f38d5e1b573d7121b219e0531b1a5d11d955ec..17ab0fe5a57751dfae4084f1b1cf18484780057e 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GenericDataProcessorPresenterFactory.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GenericDataProcessorPresenterFactory.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_GENERICDATAPROCESSORPRESENTERFACTORY_H
-#define MANTIDQTMANTIDWIDGETS_GENERICDATAPROCESSORPRESENTERFACTORY_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/GenericDataProcessorPresenter.h"
 
@@ -32,5 +31,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_GENERICDATAPROCESSORPRESENTERFACTORY_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GenericDataProcessorPresenterGroupReducerWorker.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GenericDataProcessorPresenterGroupReducerWorker.h
index 7ca0566e5b81ed2a9ad82b95c6b3ea8a6986aebb..3761614c1f1f3550d0a471d08fa022eaa23775f2 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GenericDataProcessorPresenterGroupReducerWorker.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GenericDataProcessorPresenterGroupReducerWorker.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_GENERICDATAPROCESSORPRESENTER_GENERICDATAPROCESSORPRESENTERGROUPREDUCERWORKER_H
-#define MANTIDQTMANTIDWIDGETS_GENERICDATAPROCESSORPRESENTER_GENERICDATAPROCESSORPRESENTERGROUPREDUCERWORKER_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/GenericDataProcessorPresenter.h"
 
@@ -68,5 +67,4 @@ private:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTMANTIDWIDGETS_GENERICDATAPROCESSORPRESENTER_GENERICDATAPROCESSORPRESENTERGROUPREDUCERWORKER_H
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GenericDataProcessorPresenterRowReducerWorker.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GenericDataProcessorPresenterRowReducerWorker.h
index 2e23ca01f52e171146b8aaedd96985348550af80..8e2332aed0196c141502e3e59bcbde30ce48ee26 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GenericDataProcessorPresenterRowReducerWorker.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GenericDataProcessorPresenterRowReducerWorker.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_GENERICDATAPROCESSORPRESENTER_GENERICDATAPROCESSORPRESENTERROWREDUCERWORKER_H
-#define MANTIDQTMANTIDWIDGETS_GENERICDATAPROCESSORPRESENTER_GENERICDATAPROCESSORPRESENTERROWREDUCERWORKER_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/GenericDataProcessorPresenter.h"
 
@@ -69,5 +68,3 @@ private:
 } // namespace DataProcessor
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQTMANTIDWIDGETS_GENERICDATAPROCESSORPRESENTER_GENERICDATAPROCESSORPRESENTERROWREDUCERWORKER_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GenericDataProcessorPresenterThread.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GenericDataProcessorPresenterThread.h
index 7f44112d06faf4aa412bd5b08b3b51066167c183..8ebb644fad5eb46ba71357af74b2c98d7b4c36a3 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GenericDataProcessorPresenterThread.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GenericDataProcessorPresenterThread.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_GENERICDATAPROCESSORPRESENTER_GENERICDATAPROCESSORPRESENTERTHREAD_H
-#define MANTIDQTMANTIDWIDGETS_GENERICDATAPROCESSORPRESENTER_GENERICDATAPROCESSORPRESENTERTHREAD_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/GenericDataProcessorPresenter.h"
 
@@ -52,5 +51,3 @@ private:
 } // namespace DataProcessor
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQTMANTIDWIDGETS_GENERICDATAPROCESSORPRESENTER_GENERICDATAPROCESSORPRESENTERTHREAD_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GroupRowsCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GroupRowsCommand.h
index f5c0645f3b3b0b068b0ba7994c312ab65b86427d..80f742086cbdd4743155287b24ab0e6f03216da3 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GroupRowsCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/GroupRowsCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORGROUPROWSCOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORGROUPROWSCOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 
@@ -36,5 +35,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORGROUPROWSCOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ImportTableCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ImportTableCommand.h
index 1a394ab462a2c4f1fbf36f8a40c987fdbeb81355..caf78456565d24c345175efea6b1d3a4d9a271e7 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ImportTableCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ImportTableCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORIMPORTTABLECOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORIMPORTTABLECOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 
@@ -37,5 +36,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORIMPORTTABLECOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/MockObjects.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/MockObjects.h
index 5232e2f289973a2578e47b083869699f5ac7c00f..37df12b8fdb5f0deaff05d89c3e58aeca9a564d4 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/MockObjects.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/MockObjects.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_DATAPROCESSORVIEWMOCKOBJECTS_H
-#define MANTID_MANTIDWIDGETS_DATAPROCESSORVIEWMOCKOBJECTS_H
+#pragma once
 
 #include "MantidKernel/WarningSuppressions.h"
 
@@ -251,5 +250,3 @@ public:
 };
 
 GNU_DIAG_ON_SUGGEST_OVERRIDE
-
-#endif /*MANTID_MANTIDWIDGETS_DATAPROCESSORVIEWMOCKOBJECTS_H*/
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/NewTableCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/NewTableCommand.h
index 310d09ef854d77ee0c92685c285b4e120e70cdcc..91ecc871dd56e1ed904270674b448b11716bb27c 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/NewTableCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/NewTableCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORNEWTABLECOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORNEWTABLECOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 
@@ -36,5 +35,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORNEWTABLECOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/OneLevelTreeManager.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/OneLevelTreeManager.h
index f1cc3c40766a5daeb3c53b2d459cf29483b01e17..ba0d4a122823c43e3b31620af3b5f0195734cf75 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/OneLevelTreeManager.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/OneLevelTreeManager.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORONELEVELTREEMANAGER_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORONELEVELTREEMANAGER_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/TreeManager.h"
 #include "MantidQtWidgets/Common/DllOption.h"
@@ -130,5 +129,4 @@ private:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORONELEVELTREEMANAGER_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/OpenTableCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/OpenTableCommand.h
index 15f619cd88f68b4e1fdece45a4620357c047cc68..8d62d347379a9b19c2f6a7f0789ed07dd0e69184 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/OpenTableCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/OpenTableCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSOROPENTABLECOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSOROPENTABLECOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 
@@ -38,5 +37,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSOROPENTABLECOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/OptionsCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/OptionsCommand.h
index 59e098cefea89d75e6959aa1f58020308a883455..03864e2a00136ab62e632b7727862d74f1b21e91 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/OptionsCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/OptionsCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSOROPTIONSTABLECOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSOROPTIONSTABLECOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 
@@ -36,5 +35,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSOROPTIONSTABLECOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/OptionsMap.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/OptionsMap.h
index 90fd348d2f9acc643289e5401f8deba8470ae066..89a255e3cbced700825efc11a27c609134551c19 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/OptionsMap.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/OptionsMap.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSOROPTIONSMAP_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSOROPTIONSMAP_H
+#pragma once
 /** This file defines utilities for handling option maps used by
     the DataProcessor widget.
     */
@@ -33,5 +32,4 @@ ColumnOptionsMap DLLExport
 convertColumnOptionsFromQMap(const ColumnOptionsQMap &src);
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTMANTIDWIDGETS_DATAPROCESSOROPTIONSMAP_H
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/OptionsQMap.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/OptionsQMap.h
index 82e024b7807420f5d5e3f719e6ef522a7b991acc..3dd048b8df65e8288f44779a154a31bdc576b704 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/OptionsQMap.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/OptionsQMap.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSOROPTIONSQMAP_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSOROPTIONSQMAP_H
+#pragma once
 /** This file defines utilities for handling option maps used by the data
     processor widget. These are QVariantMap equivalents of the types in
     OptionsMap.h. The QVariantMap types are required in the sip conversions for
@@ -28,5 +27,4 @@ using OptionsQMap = QVariantMap;
 using ColumnOptionsQMap = QVariantMap;
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTMANTIDWIDGETS_DATAPROCESSOROPTIONSQMAP_H
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PasteSelectedCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PasteSelectedCommand.h
index b99403af81c14a16256eae99847c4e69b6e53d38..50592c6994251835db8fb35dcd06c45e874a0500 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PasteSelectedCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PasteSelectedCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORPASTESELECTEDCOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORPASTESELECTEDCOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 
@@ -39,5 +38,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORPASTESELECTEDCOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PauseCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PauseCommand.h
index ec18c37b9f619f6f1394f94762c1b2aee28eb6c8..54df542c3627b16a482f4ff3e2568d07e0bcd62d 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PauseCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PauseCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORPAUSECOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORPAUSECOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 
@@ -38,5 +37,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORPAUSECOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PlotGroupCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PlotGroupCommand.h
index 52182132d599e59683bb9815680ff85581097821..e31f9ab2746f5282d049de584085abbd8cf70a1c 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PlotGroupCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PlotGroupCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORPLOTGROUPCOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORPLOTGROUPCOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 
@@ -38,5 +37,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORPLOTGROUPCOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PlotRowCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PlotRowCommand.h
index 9d6489b2dda73b194b8b1094b83f6a7dc51068c4..2210de302b1944c86cae54eb4204ba3dc4c04524 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PlotRowCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PlotRowCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORPLOTROWCOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORPLOTROWCOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 
@@ -38,5 +37,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORPLOTROWCOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PostprocessingAlgorithm.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PostprocessingAlgorithm.h
index a5fc6086956fbb123006121a8a348586e8fff1ff..a3e56491e8e76c973c7a9a85537f572b4b0cf5ed 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PostprocessingAlgorithm.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PostprocessingAlgorithm.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORPOSTPROCESSINGALGORITHM_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORPOSTPROCESSINGALGORITHM_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/ProcessingAlgorithmBase.h"
 #include "MantidQtWidgets/Common/DllOption.h"
@@ -53,5 +52,4 @@ private:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORPOSTPROCESSINGALGORITHM_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PostprocessingStep.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PostprocessingStep.h
index 51648979e02a6dd9b1538f1d08bb300cfa1f9995..c0d540afbdd18f37ef504a67ff4cf4862f8f6b1c 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PostprocessingStep.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PostprocessingStep.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTWIDGETS_POSTPROCESSINGSTEP
-#define MANTIDQTWIDGETS_POSTPROCESSINGSTEP
+#pragma once
 #include "MantidAPI/AlgorithmManager.h"
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidQtWidgets/Common/DataProcessorUI/PostprocessingAlgorithm.h"
@@ -45,5 +44,4 @@ private:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTWIDGETS_POSTPROCESSINGSTEP
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PreprocessMap.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PreprocessMap.h
index 3e7c6d092ad00841d648ef850edbea519cfadaa0..4ee90c9e7cbb72a60404a6349e52ecf17da95837 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PreprocessMap.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PreprocessMap.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORPREPROCESSMAP_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORPREPROCESSMAP_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/PreprocessingAlgorithm.h"
 #include "MantidQtWidgets/Common/DllOption.h"
@@ -41,5 +40,4 @@ private:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORPREPROCESSMAP_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PreprocessingAlgorithm.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PreprocessingAlgorithm.h
index 994ae7139aaf80a2323a101c1849bc45999ea507..2f82f64e542135548f3bab22411856f40c3332a3 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PreprocessingAlgorithm.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/PreprocessingAlgorithm.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORPREPROCESSINGALGORITHM_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORPREPROCESSINGALGORITHM_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/ProcessingAlgorithmBase.h"
 #include "MantidQtWidgets/Common/DllOption.h"
@@ -60,5 +59,4 @@ private:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORPREPROCESSINGALGORITHM_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ProcessCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ProcessCommand.h
index 5ac5c30dbc2eee7bae03c23ea540df1065bb7d39..61ba97b03324a8b2065e477d33f55764cde08d5f 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ProcessCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ProcessCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORPROCESSCOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORPROCESSCOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 
@@ -40,5 +39,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORPROCESSCOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ProcessingAlgorithm.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ProcessingAlgorithm.h
index 9d718e30360258a2a943dd6e611081bcfd26adb9..0b4e3ab5f50ba357604fbc5205d2eaf7381fc721 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ProcessingAlgorithm.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ProcessingAlgorithm.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORPROCESSINGALGORITHM_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORPROCESSINGALGORITHM_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/ProcessingAlgorithmBase.h"
 #include "MantidQtWidgets/Common/DllOption.h"
@@ -74,5 +73,4 @@ private:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORPROCESSINGALGORITHM_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ProcessingAlgorithmBase.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ProcessingAlgorithmBase.h
index cc679f2a1a3bd0539ddc5bd4876a25872de5fb88..fd8b12607b39e4326f5c6e90926fdee21a676304 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ProcessingAlgorithmBase.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ProcessingAlgorithmBase.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORALGORITHMBASE_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORALGORITHMBASE_H
+#pragma once
 
 #include "MantidAPI/AlgorithmManager.h"
 #include "MantidQtWidgets/Common/DllOption.h"
@@ -79,5 +78,4 @@ protected:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORALGORITHMBASE_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/QDataProcessorWidget.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/QDataProcessorWidget.h
index ec6ac6c6591e189c23c8dc1ccc77f224ff18a2f6..61bb171b38ce13f9ecc1249bee8f07929d6a7572 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/QDataProcessorWidget.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/QDataProcessorWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_QDATAPROCESSORWIDGET_H_
-#define MANTIDQTMANTIDWIDGETS_QDATAPROCESSORWIDGET_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 #include "MantidQtWidgets/Common/DataProcessorUI/AbstractTreeModel.h"
@@ -194,5 +193,4 @@ private slots:
 
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /* MANTIDQTMANTIDWIDGETS_QDATAPROCESSORWIDGET_H_ */
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/QOneLevelTreeModel.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/QOneLevelTreeModel.h
index 579a920c06223fdb0faad6c9081c7355efbaa4a2..09c30594bf300a25f6b6910d04dcab5a7ab418bd 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/QOneLevelTreeModel.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/QOneLevelTreeModel.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_QDATAPROCESSORONELEVELTREEMODEL_H_
-#define MANTIDQTMANTIDWIDGETS_QDATAPROCESSORONELEVELTREEMODEL_H_
+#pragma once
 
 #include "MantidAPI/ITableWorkspace_fwd.h"
 #include "MantidQtWidgets/Common/DataProcessorUI/AbstractTreeModel.h"
@@ -107,5 +106,3 @@ using QOneLevelTreeModel_sptr = boost::shared_ptr<QOneLevelTreeModel>;
 } // namespace DataProcessor
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTIDQTMANTIDWIDGETS_QDATAPROCESSORONELEVELTREEMODEL_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/QTwoLevelTreeModel.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/QTwoLevelTreeModel.h
index d6ae35ac0de818d2714228bbd313f7407f676b61..a66f7ec0d03c7d4254bc8fa0ced5188365dc6eda 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/QTwoLevelTreeModel.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/QTwoLevelTreeModel.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_QDATAPROCESSORTWOLEVELTREEMODEL_H_
-#define MANTIDQTMANTIDWIDGETS_QDATAPROCESSORTWOLEVELTREEMODEL_H_
+#pragma once
 
 #include "MantidAPI/ITableWorkspace_fwd.h"
 #include "MantidQtWidgets/Common/DataProcessorUI/AbstractTreeModel.h"
@@ -154,5 +153,3 @@ using QTwoLevelTreeModel_sptr = boost::shared_ptr<QTwoLevelTreeModel>;
 } // namespace DataProcessor
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTIDQTMANTIDWIDGETS_QDATAPROCESSORTWOLEVELTREEMODEL_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/QtCommandAdapter.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/QtCommandAdapter.h
index 345362ac6323305accac97c6377f6c7e7e84cde4..79cdc66b60986d38a81ec1ebc3a0537437144ee1 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/QtCommandAdapter.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/QtCommandAdapter.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORCOMMANDADAPTER_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORCOMMANDADAPTER_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/Command.h"
 #include "MantidQtWidgets/Common/DllOption.h"
@@ -141,5 +140,4 @@ private:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORCOMMANDADAPTER_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/QtDataProcessorOptionsDialog.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/QtDataProcessorOptionsDialog.h
index 201a5da64b7f7e64bfd1ff69c32ec1162a34da99..c609795560a46e8838ad08f4f16894fcbc1ac2e8 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/QtDataProcessorOptionsDialog.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/QtDataProcessorOptionsDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_QTDATAPROCESSOROPTIONSDIALOG_H
-#define MANTIDQTMANTIDWIDGETS_QTDATAPROCESSOROPTIONSDIALOG_H
+#pragma once
 
 #include "MantidKernel/System.h"
 
@@ -51,5 +50,3 @@ protected:
 } // namespace DataProcessor
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTIDQTMANTIDWIDGETS_QTDATAPROCESSOROPTIONSDIALOG_H */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/SaveTableAsCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/SaveTableAsCommand.h
index 1f8aa9738b927292f9f3f44e159bd9c0656b23e3..edb6e8ff36ac62fd116666399080d077482d2248 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/SaveTableAsCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/SaveTableAsCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORSAVETABLEASCOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORSAVETABLEASCOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 
@@ -39,5 +38,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORSAVETABLEASCOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/SaveTableCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/SaveTableCommand.h
index 79b2389f1fae7f2db128909e9fa0ed2b854f2fe6..b64d500d4033bd46d6f13e24b020156ba7f3f7d4 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/SaveTableCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/SaveTableCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORSAVETABLECOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORSAVETABLECOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 
@@ -37,5 +36,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORSAVETABLECOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/SeparatorCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/SeparatorCommand.h
index 7d033c4b76e0fce4d857c2d78747d4c912b1ab91..0affea6e9b1d3966b4149aaad5286e0aef18de42 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/SeparatorCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/SeparatorCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORSEPARATORCOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORSEPARATORCOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 
@@ -35,5 +34,4 @@ public:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORSEPARATORCOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ToStdStringMap.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ToStdStringMap.h
index 603bc2cac26d8d0ce29b209cd5c064e298c009c9..2607192e1338dacd2ffcaad96cc47429dc6afefc 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ToStdStringMap.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/ToStdStringMap.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_DATAPROCESSORTOSTDSTRINGMAP_H
-#define MANTID_MANTIDWIDGETS_DATAPROCESSORTOSTDSTRINGMAP_H
+#pragma once
 #include "MantidQtWidgets/Common/DllOption.h"
 #include <QString>
 #include <map>
@@ -22,5 +21,4 @@ std::map<std::string, std::string> EXPORT_OPT_MANTIDQT_COMMON
 toStdStringMap(std::map<QString, QString> const &inMap);
 }
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTID_MANTIDWIDGETS_DATAPROCESSORTOSTDSTRINGMAP_H
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/TreeData.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/TreeData.h
index 6fa152a4539f5c7a6060b740b984b05d95c29082..23844f7e58df121511cd97d0ab37afa0d2645780 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/TreeData.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/TreeData.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORTREEDATA_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORTREEDATA_H
+#pragma once
 /** This file defines the RowData, GroupData and TreeData type aliases used by
    the
     DataProcessor widget.
@@ -150,5 +149,4 @@ using TreeData = std::map<int, GroupData>;
 EXPORT_OPT_MANTIDQT_COMMON bool canPostprocess(GroupData const &group);
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTMANTIDWIDGETS_DATAPROCESSORTREEDATA_H
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/TreeManager.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/TreeManager.h
index 5ac4b23b47b3cb2871a82e279a0b9c1f2e41bf8e..0ff878b036ac96f40083201bbdd40eb54dc425b6 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/TreeManager.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/TreeManager.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORTREEMANAGER_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORTREEMANAGER_H
+#pragma once
 
 #include "MantidAPI/ITableWorkspace_fwd.h"
 #include "MantidAPI/Workspace_fwd.h"
@@ -120,5 +119,4 @@ protected:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /* MANTIDQTMANTIDWIDGETS_DATAPROCESSORTREEMANAGER_H */
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/TwoLevelTreeManager.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/TwoLevelTreeManager.h
index 7eb96e39196f9e2fae728118cadcc8c27e51cf2b..a9e6bb0a410995af9dad2c90d57fcf6c8bdafafb 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/TwoLevelTreeManager.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/TwoLevelTreeManager.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORTWOLEVELTREEMANAGER_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORTWOLEVELTREEMANAGER_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/TreeManager.h"
 #include "MantidQtWidgets/Common/DllOption.h"
@@ -129,5 +128,4 @@ private:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORTWOLEVELTREEMANAGER_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/VectorString.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/VectorString.h
index 6275c1e7191a5c250d87d75542e1a75fd766ca71..74fcfe906f6ecfc921e690dd1482ed99115c8748 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/VectorString.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/VectorString.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORVECTORSTRING_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORVECTORSTRING_H
+#pragma once
 
 /** @class VectorString
  */
@@ -70,5 +69,4 @@ QString vectorParamString(const QString &param_name,
 }
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQTMANTIDWIDGETS_DATAPROCESSORVECTORSTRING_H
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/WhiteList.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/WhiteList.h
index b55467d81e26d8c8aff06ef5f04afe8ce3e22db2..911d524befbf0073749fae4000908fa85e46dd6f 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/WhiteList.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/WhiteList.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORWHITELIST_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORWHITELIST_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/Column.h"
 #include "MantidQtWidgets/Common/DataProcessorUI/ConstColumnIterator.h"
@@ -61,5 +60,4 @@ private:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORWHITELIST_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/WorkspaceCommand.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/WorkspaceCommand.h
index fa563fdc980f454ebf9eddded0654629b33a9ccf..5b792b5c2af0b6bc39245842874192eeeb886bfd 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/WorkspaceCommand.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/WorkspaceCommand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATAPROCESSORWORKSPACECOMMAND_H
-#define MANTIDQTMANTIDWIDGETS_DATAPROCESSORWORKSPACECOMMAND_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DataProcessorUI/CommandBase.h"
 
@@ -39,5 +38,4 @@ private:
 };
 } // namespace DataProcessor
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MANTIDQTMANTIDWIDGETS_DATAPROCESSORWORKSPACECOMMAND_H*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/WorkspaceNameUtils.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/WorkspaceNameUtils.h
index 3a367a4be044068a1275e670b852ad8b58d57399..f87b7c2b58ec7d26871fb9828e9fd15c74c5a591 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/WorkspaceNameUtils.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataProcessorUI/WorkspaceNameUtils.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETSDATAPROCESSOR_WORKSPACENAMEUTILS_H
-#define MANTIDQTMANTIDWIDGETSDATAPROCESSOR_WORKSPACENAMEUTILS_H
+#pragma once
 
 /** Utilities for finding the output name of reduced workspaces based
 on the reduction algorithm's input values and preprocessing settings
@@ -43,5 +42,3 @@ OptionsMap DLLExport getCanonicalOptions(
 } // namespace DataProcessor
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQTMANTIDWIDGETSDATAPROCESSOR_WORKSPACENAMEUTILS_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DataSelector.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DataSelector.h
index c4a2c040c8dcb351a400269961645285b0ead401..770efb3a91af87f99d481c5a4b23de41c01d87ae 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DataSelector.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DataSelector.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_DATASELECTOR_H_
-#define MANTIDQTMANTIDWIDGETS_DATASELECTOR_H_
+#pragma once
 
 #include "DllOption.h"
 #include "ui_DataSelector.h"
@@ -439,5 +438,4 @@ private:
 };
 
 } /* namespace MantidWidgets */
-} /* namespace MantidQt */
-#endif /* DATASELECTOR_H_ */
+} /* namespace MantidQt */
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DiagResults.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DiagResults.h
index b5951be61e08090ae94c213b7da4f969ff65a345..1a6e976dc33142c3428ec1f011bc4d20751d9307 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DiagResults.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DiagResults.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTCUSTOMINTERFACES_EXCITATIONSDIAGRESULTS_H_
-#define MANTIDQTCUSTOMINTERFACES_EXCITATIONSDIAGRESULTS_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidQtWidgets/Common/MantidDialog.h"
@@ -39,5 +38,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQTCUSTOMINTERFACES_EXCITATIONSDIAGRESULTS_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DistributionOptions.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DistributionOptions.h
index d97207f721b17e9b72e3679dc3ae3338c8ca802d..37a1ba165da147801726d9897cf798a97147732e 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DistributionOptions.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DistributionOptions.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DISTRIBUTIONOPTIONS_H_
-#define DISTRIBUTIONOPTIONS_H_
+#pragma once
 
 /**
  * This file contains declarations of options which control
@@ -20,5 +19,3 @@ enum DistributionFlag {
   DistributionFalse        // Disable distribution plotting
 };
 } // namespace MantidQt
-
-#endif // DISTRIBUTIONOPTIONS_H_
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DllOption.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DllOption.h
index 527cbb3cf6b6c3dce3523f9f71b3130bc783d0b7..f774b819a9b14a97428e16b059864a86cc1c820b 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DllOption.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DllOption.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_COMMON_DLLOPTION_H_
-#define MANTIDQT_COMMON_DLLOPTION_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 
@@ -16,5 +15,3 @@
 #define EXPORT_OPT_MANTIDQT_COMMON DLLImport
 #define EXTERN_MANTIDQT_COMMON extern
 #endif /* IN_MANTIDQT_COMMON */
-
-#endif // MANTIDQT_COMMON_DLLOPTION_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DoubleSpinBox.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DoubleSpinBox.h
index 68a9e0f304bca24f59c1d01d18da42f651aa3f3a..d8c2969291da4209eb9d4d8984ed1c7fef65f5da 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DoubleSpinBox.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DoubleSpinBox.h
@@ -15,8 +15,7 @@
  *   Boston, MA  02110-1301  USA                                           *
  *                                                                         *
  ***************************************************************************/
-#ifndef DoubleSpinBox_H
-#define DoubleSpinBox_H
+#pragma once
 
 #include "DllOption.h"
 #include <map>
@@ -109,5 +108,4 @@ private:
   DoubleSpinBox *d_spin_box;
   QCheckBox *d_checkbox;
   LimitType d_type;
-};
-#endif // FITDIALOG_H
+};
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/DropEventHelper.h b/qt/widgets/common/inc/MantidQtWidgets/Common/DropEventHelper.h
index 81afd2aa86cbb2b560b903e56994536753d11ee0..135dffba09f6e715d3663b505d99872ca035711c 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/DropEventHelper.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/DropEventHelper.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGETS_DROPEVENTHELPER_H
-#define MANTIDQT_MANTIDWIDGETS_DROPEVENTHELPER_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DllOption.h"
 
@@ -25,5 +24,3 @@ extractPythonFiles(const QDropEvent *event);
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/EditLocalParameterDialog.h b/qt/widgets/common/inc/MantidQtWidgets/Common/EditLocalParameterDialog.h
index 7290e2855dd3462ec305fb052f4a2678dd035d2f..fb7a69b4d16e3b2542062dcdce236e7b9d7c6b8d 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/EditLocalParameterDialog.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/EditLocalParameterDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDWIDGETS_EDITLOCALPARAMETERDIALOG_H_
-#define MANTIDWIDGETS_EDITLOCALPARAMETERDIALOG_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidQtWidgets/Common/LogValueFinder.h"
@@ -87,5 +86,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*MANTIDWIDGETS_EDITLOCALPARAMETERDIALOG_H_*/
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/FileDialogHandler.h b/qt/widgets/common/inc/MantidQtWidgets/Common/FileDialogHandler.h
index a13d62e447ca6bc55a2990c4c50e2b9e887956b3..e0c44dbadb86bc5188bf0d2269530ad154a7c3ce 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/FileDialogHandler.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/FileDialogHandler.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_FILEDIALOGHANDLER_H_
-#define MANTIDQT_API_FILEDIALOGHANDLER_H_
+#pragma once
 
 #include "MantidKernel/DllConfig.h"
 #include <QFileDialog>
@@ -68,5 +67,3 @@ DLLExport QString getCaption(const std::string &dialogName,
 } // namespace FileDialogHandler
 } // namespace API
 } // namespace MantidQt
-
-#endif // MANTIDQT_API_FILEDIALOGHANDLER_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/FilePropertyWidget.h b/qt/widgets/common/inc/MantidQtWidgets/Common/FilePropertyWidget.h
index e5a63e10464bde65f50127916f3039e13738af20..c760cc6a30bd7075920bb4177b0c3bee08ec7153 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/FilePropertyWidget.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/FilePropertyWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_API_FILEPROPERTYWIDGET_H_
-#define MANTID_API_FILEPROPERTYWIDGET_H_
+#pragma once
 
 #include "MantidAPI/FileProperty.h"
 #include "MantidAPI/MultipleFileProperty.h"
@@ -49,5 +48,3 @@ protected:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif /* MANTID_API_FILEPROPERTYWIDGET_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/FilenameDialogEditor.h b/qt/widgets/common/inc/MantidQtWidgets/Common/FilenameDialogEditor.h
index 66bede234e505fe1293ddf643de987b5dbe4ee13..b91bc247c6dde3f0815b353157937c92a29dc3b0 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/FilenameDialogEditor.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/FilenameDialogEditor.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGETS_FILENAMEDIALOGEDITFACTORY_H
-#define MANTIDQT_MANTIDWIDGETS_FILENAMEDIALOGEDITFACTORY_H
+#pragma once
 
 #include "MantidQtWidgets/Common/QtPropertyBrowser/StringDialogEditor.h"
 
@@ -45,5 +44,3 @@ protected:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQT_MANTIDWIDGETS_FILENAMEDIALOGEDITFACTORY_H
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/FindDialog.h b/qt/widgets/common/inc/MantidQtWidgets/Common/FindDialog.h
index 4fcda4e961f96807db0281d63e099d51a516fa85..5e65bb4f4eb743021e0bf71b92aaa0155528ef0e 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/FindDialog.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/FindDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef FINDDIALOG_H_
-#define FINDDIALOG_H_
+#pragma once
 
 //--------------------------------------------------
 // Includes
@@ -22,5 +21,3 @@ class EXPORT_OPT_MANTIDQT_COMMON FindDialog : public FindReplaceDialog {
 public:
   FindDialog(ScriptEditor *editor);
 };
-
-#endif // FINDDIALOG_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/FindFilesThreadPoolManager.h b/qt/widgets/common/inc/MantidQtWidgets/Common/FindFilesThreadPoolManager.h
index 18ac8c262b9ce8e1a12cd8ee529e65b75a495c2b..01b32870661c705b37afbdb30b575ec910ee07ed 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/FindFilesThreadPoolManager.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/FindFilesThreadPoolManager.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_FINDFILESTHREADPOOLMANAGER_H_
-#define MANTIDQTMANTIDWIDGETS_FINDFILESTHREADPOOLMANAGER_H_
+#pragma once
 
 #include "MantidQtWidgets/Common/DllOption.h"
 #include "MantidQtWidgets/Common/FindFilesWorker.h"
@@ -70,5 +69,3 @@ private:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif // MANTIDQTMANTIDWIDGETS_FINDFILESTHREADPOOLMANAGER_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/FindFilesThreadPoolManagerMockObjects.h b/qt/widgets/common/inc/MantidQtWidgets/Common/FindFilesThreadPoolManagerMockObjects.h
index 59fb8890872b787b8c1b6ff3b06310954af62118..ee73d7d2ce0c63ed976ed496f94e6dd62f3054e7 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/FindFilesThreadPoolManagerMockObjects.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/FindFilesThreadPoolManagerMockObjects.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_FINDFILESTHREADPOOLMANAGERTESTMOCKOBJECTS_H_
-#define MANTIDQT_API_FINDFILESTHREADPOOLMANAGERTESTMOCKOBJECTS_H_
+#pragma once
 
 #include "MantidQtWidgets/Common/DllOption.h"
 #include "MantidQtWidgets/Common/FindFilesThreadPoolManager.h"
@@ -104,5 +103,3 @@ private:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif /* MANTIDQT_API_FINDFILESTHREADPOOLMANAGERTESTMOCKOBJECTS_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/FindFilesWorker.h b/qt/widgets/common/inc/MantidQtWidgets/Common/FindFilesWorker.h
index ee8e1887d5075a14fb4397ef41c4cdbab012fdeb..8dae8a10045c8cde9eabd196091967dba8db6363 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/FindFilesWorker.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/FindFilesWorker.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_FINDFILESWORKER_H_
-#define MANTIDQTMANTIDWIDGETS_FINDFILESWORKER_H_
+#pragma once
 
 #include "MantidQtWidgets/Common/DllOption.h"
 
@@ -98,5 +97,3 @@ private:
 // Add to Qt's meta type system. This allows the type
 // to be passed between signals & slots
 Q_DECLARE_METATYPE(MantidQt::API::FindFilesSearchResults)
-
-#endif // MANTIDQTMANTIDWIDGETS_FINDFILESWORKER_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/FindReplaceDialog.h b/qt/widgets/common/inc/MantidQtWidgets/Common/FindReplaceDialog.h
index 33cf568306053d8c0679f982badcb48db7ef9879..e508b0abc55bc73d4d3543d97a7ef1c9b5c4ff96 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/FindReplaceDialog.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/FindReplaceDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef FINDREPLACEDIALOG_H_
-#define FINDREPLACEDIALOG_H_
+#pragma once
 
 //----------------------------------
 // Includes
@@ -99,5 +98,3 @@ private:
   QGridLayout *m_topLayout;
   QVBoxLayout *m_vb2;
 };
-
-#endif // FINDREPLACEDIALOG_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/FitOptionsBrowser.h b/qt/widgets/common/inc/MantidQtWidgets/Common/FitOptionsBrowser.h
index d9c6796ec4ddf7316295b1651d0ec3b266db3219..b7ec9e0adc40d1200a329e75558d68579efed284 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/FitOptionsBrowser.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/FitOptionsBrowser.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDWIDGETS_FITOPTIONSBROWSER_H_
-#define MANTIDWIDGETS_FITOPTIONSBROWSER_H_
+#pragma once
 
 #include "DllOption.h"
 
@@ -190,5 +189,3 @@ private:
 } // namespace MantidWidgets
 
 } // namespace MantidQt
-
-#endif /*MANTIDWIDGETS_FITOPTIONSBROWSER_H_*/
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/FitPropertyBrowser.h b/qt/widgets/common/inc/MantidQtWidgets/Common/FitPropertyBrowser.h
index e5d1b5425663cc14ec375d102355e74633c97f65..5582f6e7d92b4f38ac20c3d2970cf3447791e060 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/FitPropertyBrowser.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/FitPropertyBrowser.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef FITPROPERTYBROWSER_H_
-#define FITPROPERTYBROWSER_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidAPI/AlgorithmObserver.h"
@@ -708,5 +707,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*FITPROPERTYBROWSER_H_*/
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/FlowLayout.h b/qt/widgets/common/inc/MantidQtWidgets/Common/FlowLayout.h
index 1b820e6e6248386912194dc2c000f5000a4cfc42..577ee2986b05ea13acabb494dc8a21328b7de2a4 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/FlowLayout.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/FlowLayout.h
@@ -38,8 +38,7 @@
 **
 ****************************************************************************/
 
-#ifndef FLOWLAYOUT_H
-#define FLOWLAYOUT_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DllOption.h"
 #include <QLayout>
@@ -79,5 +78,3 @@ private:
 };
 } // namespace API
 } // namespace MantidQt
-
-#endif
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/FunctionBrowser.h b/qt/widgets/common/inc/MantidQtWidgets/Common/FunctionBrowser.h
index b4e8907a2cbdb3077e2d50304914714a39089b7b..a7963d369e111fda326d21c0ece6f4fea9d4336d 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/FunctionBrowser.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/FunctionBrowser.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDWIDGETS_FUNCTIONBROWSER_H_
-#define MANTIDWIDGETS_FUNCTIONBROWSER_H_
+#pragma once
 
 #include "DllOption.h"
 
@@ -157,5 +156,3 @@ public:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*MANTIDWIDGETS_FUNCTIONBROWSER_H_*/
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/FunctionBrowser/FunctionBrowserUtils.h b/qt/widgets/common/inc/MantidQtWidgets/Common/FunctionBrowser/FunctionBrowserUtils.h
index dee56ed913b1f8ed14230de1b275b61459ba5406..9650be03205f6dcec552a97b76ca8d3b386f1f0f 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/FunctionBrowser/FunctionBrowserUtils.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/FunctionBrowser/FunctionBrowserUtils.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDWIDGETS_FUNCTIONBROWSERUTILS_H_
-#define MANTIDWIDGETS_FUNCTIONBROWSERUTILS_H_
+#pragma once
 #include "MantidAPI/IFunction_fwd.h"
 #include "MantidQtWidgets/Common/DllOption.h"
 
@@ -58,5 +57,3 @@ public:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDWIDGETS_FUNCTIONBROWSERUTILS_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/FunctionModel.h b/qt/widgets/common/inc/MantidQtWidgets/Common/FunctionModel.h
index 2abd3734a9d8d788d742b7f55bdcbc854fb5037e..e989b6812eb116d8962cb0daeb9fed6039bcbc6d 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/FunctionModel.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/FunctionModel.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDWIDGETS_FUNCTIONMODEL_H_
-#define MANTIDWIDGETS_FUNCTIONMODEL_H_
+#pragma once
 
 #include "DllOption.h"
 
@@ -85,5 +84,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDWIDGETS_FUNCTIONMODEL_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/FunctionMultiDomainPresenter.h b/qt/widgets/common/inc/MantidQtWidgets/Common/FunctionMultiDomainPresenter.h
index af82c056cc83a5ad0002013efe7c192c0bcc71d2..eb552e0f12b71e97447c66d29f942ea7740d2ce9 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/FunctionMultiDomainPresenter.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/FunctionMultiDomainPresenter.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDWIDGETS_FUNCTIONMULTIDOMAINPRESENTER_H_
-#define MANTIDWIDGETS_FUNCTIONMULTIDOMAINPRESENTER_H_
+#pragma once
 
 #include "DllOption.h"
 
@@ -106,5 +105,3 @@ public:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDWIDGETS_FUNCTIONMULTIDOMAINPRESENTER_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/FunctionTreeView.h b/qt/widgets/common/inc/MantidQtWidgets/Common/FunctionTreeView.h
index 2de491a18af66204d47dbe7e938948f93f83ba70..d7db6f5801f89ac43dd4816c8d14917a01be351f 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/FunctionTreeView.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/FunctionTreeView.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDWIDGETS_FUNCTIONTREEVIEW_H_
-#define MANTIDWIDGETS_FUNCTIONTREEVIEW_H_
+#pragma once
 
 #include "DllOption.h"
 
@@ -374,5 +373,3 @@ public:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*MANTIDWIDGETS_FUNCTIONTREEVIEW_H_*/
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/GenericDialog.h b/qt/widgets/common/inc/MantidQtWidgets/Common/GenericDialog.h
index 6522682960b9ba0cbbdeabe67acce30a27be0375..a79c700906b5453279f42771d1b7afef1c9593bd 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/GenericDialog.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/GenericDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_GENERICDIALOG_H_
-#define MANTIDQT_API_GENERICDIALOG_H_
+#pragma once
 
 //----------------------------------
 // Includes
@@ -58,5 +57,3 @@ private:
 };
 } // namespace API
 } // namespace MantidQt
-
-#endif // MANTIDQT_API_GENERICDIALOG_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/GraphOptions.h b/qt/widgets/common/inc/MantidQtWidgets/Common/GraphOptions.h
index 8700e6d251a95f0505c10fef08e9ead45d780872..f99c0c36a1ebb6f972d7e6dafc290fc9ceee8ce6 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/GraphOptions.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/GraphOptions.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDGRAPHOPTIONS_H_
-#define MANTIDGRAPHOPTIONS_H_
+#pragma once
 
 /**
  * This file contains declarations of options such as scale types that are
@@ -53,5 +52,3 @@ enum CurveType {
   User
 };
 } // namespace GraphOptions
-
-#endif // MANTIDSCALETYPE_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/HelpWindow.h b/qt/widgets/common/inc/MantidQtWidgets/Common/HelpWindow.h
index 007b0f9777a15a5ee4c6eaa6ddd36f2146d1d8eb..b7743796c8db89b36168bc398d423db44643c1b4 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/HelpWindow.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/HelpWindow.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef HELPWINDOW_H
-#define HELPWINDOW_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DllOption.h"
 #include <QString>
@@ -40,5 +39,4 @@ public:
                                   const std::string &section = std::string());
 };
 } // namespace API
-} // namespace MantidQt
-#endif // HELPWINDOW_H
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Hint.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Hint.h
index a88ef44b87a72552091d2dc3670482348a676391..13710b117da6a7368866fef22448fd8a3b3ffc41 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Hint.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Hint.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_HINT_H_
-#define MANTID_MANTIDWIDGETS_HINT_H_
+#pragma once
 #include "DllOption.h"
 #include <string>
 
@@ -26,5 +25,4 @@ private:
 EXPORT_OPT_MANTIDQT_COMMON bool operator==(Hint const &lhs, Hint const &rhs);
 EXPORT_OPT_MANTIDQT_COMMON bool operator!=(Hint const &lhs, Hint const &rhs);
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTID_MANTIDWIDGETS_HINT_H_
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/HintStrategy.h b/qt/widgets/common/inc/MantidQtWidgets/Common/HintStrategy.h
index e1943fd6acd7de76793fa8e2fa4c78b31ed5b4f1..0e9a687fd408812b1a233697ec35dd4a819f2f6f 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/HintStrategy.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/HintStrategy.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_HINTSTRATEGY_H
-#define MANTID_MANTIDWIDGETS_HINTSTRATEGY_H
+#pragma once
 
 #include "DllOption.h"
 #include "MantidQtWidgets/Common/Hint.h"
@@ -33,5 +32,3 @@ public:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTID_MANTIDWIDGETS_HINTSTRATEGY_H */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/HintingLineEdit.h b/qt/widgets/common/inc/MantidQtWidgets/Common/HintingLineEdit.h
index c2e15982e4354e196a054f4bf7d8deffd73d9a55..99d5108d0cfbc55fc2d4a15d2cc16e84aa2f1990 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/HintingLineEdit.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/HintingLineEdit.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_HINTINGLINEEDIT_H_
-#define MANTID_MANTIDWIDGETS_HINTINGLINEEDIT_H_
+#pragma once
 
 #include "DllOption.h"
 #include "Hint.h"
@@ -52,5 +51,3 @@ protected slots:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTID_MANTIDWIDGETS_HINTINGLINEEDIT_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/HintingLineEditFactory.h b/qt/widgets/common/inc/MantidQtWidgets/Common/HintingLineEditFactory.h
index 25f596efa0ad0b1b1278ed79c2568c877aec4704..7cf0e023cbb49f5909b207c3b4a6aa7ff8355c95 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/HintingLineEditFactory.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/HintingLineEditFactory.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_HINTINGLINEEDITFACTORY_H
-#define MANTID_MANTIDWIDGETS_HINTINGLINEEDITFACTORY_H
+#pragma once
 
 #include <QPainter>
 #include <QStyledItemDelegate>
@@ -50,5 +49,3 @@ protected:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTID_MANTIDWIDGETS_HINTINGLINEEDITFACTORY_H */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/IFunctionBrowser.h b/qt/widgets/common/inc/MantidQtWidgets/Common/IFunctionBrowser.h
index 785f7057f84be0b7e188fe39d06abe822bf8c472..a92fb02338393d5daed0aa715ef97260370fc71d 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/IFunctionBrowser.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/IFunctionBrowser.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_IFUNCTIONBROWSER_H_
-#define MANTID_MANTIDWIDGETS_IFUNCTIONBROWSER_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidAPI/IFunction_fwd.h"
@@ -53,5 +52,3 @@ public:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTID_MANTIDWIDGETS_IFUNCTIONBROWSER_H
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/IFunctionModel.h b/qt/widgets/common/inc/MantidQtWidgets/Common/IFunctionModel.h
index 6ab79bb2cd7339d47a0709b0bc4239b4df03dd4a..398b9c030a585e3ffadbd69d1184c4a1e3e855a4 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/IFunctionModel.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/IFunctionModel.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDWIDGETS_IFUNCTIONMODEL_H_
-#define MANTIDWIDGETS_IFUNCTIONMODEL_H_
+#pragma once
 
 #include "DllOption.h"
 
@@ -82,5 +81,3 @@ protected:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDWIDGETS_IFUNCTIONMODEL_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/IFunctionView.h b/qt/widgets/common/inc/MantidQtWidgets/Common/IFunctionView.h
index d9aa2b737383179145e29bc25dbf201f4d5d1cfa..d42392a8e0fbeeb4651132040c8ab1520f0c1c66 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/IFunctionView.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/IFunctionView.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDWIDGETS_IFUNCTIONVIEW_H_
-#define MANTIDWIDGETS_IFUNCTIONVIEW_H_
+#pragma once
 
 #include "DllOption.h"
 
@@ -71,5 +70,3 @@ signals:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*MANTIDWIDGETS_IFUNCTIONVIEW_H_*/
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/IMuonFitDataModel.h b/qt/widgets/common/inc/MantidQtWidgets/Common/IMuonFitDataModel.h
index 876bb4b6826dd2d4a15eed9e69edbe8b9c10559b..e18b4b6a900975849498152a13dbb07235dbf867 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/IMuonFitDataModel.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/IMuonFitDataModel.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_IMUONFITDATAMODEL_H_
-#define MANTID_MANTIDWIDGETS_IMUONFITDATAMODEL_H_
+#pragma once
 
 #include "DllOption.h"
 #include <QObject>
@@ -32,5 +31,3 @@ signals:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTID_MANTIDWIDGETS_IMUONFITDATAMODEL_H
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/IMuonFitDataSelector.h b/qt/widgets/common/inc/MantidQtWidgets/Common/IMuonFitDataSelector.h
index 2ec8526cae8b576a051d3bde016942c80c3639fd..f1e9529c37c674124de80ae1688abac149fb447f 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/IMuonFitDataSelector.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/IMuonFitDataSelector.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_IMUONFITDATASELECTOR_H_
-#define MANTID_MANTIDWIDGETS_IMUONFITDATASELECTOR_H_
+#pragma once
 
 #include "DllOption.h"
 #include <QString>
@@ -48,5 +47,3 @@ public:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTID_MANTIDWIDGETS_IMUONFITDATASELECTOR_H_ */
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/IMuonFitFunctionModel.h b/qt/widgets/common/inc/MantidQtWidgets/Common/IMuonFitFunctionModel.h
index 46d23163ff935b466f82b77653aaddcd74c70600..26e844744483abd896d4c47c08b67cf977f54185 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/IMuonFitFunctionModel.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/IMuonFitFunctionModel.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_IMUONFITFUNCTIONMODEL_H_
-#define MANTID_MANTIDWIDGETS_IMUONFITFUNCTIONMODEL_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidAPI/IFunction.h"
@@ -40,5 +39,3 @@ signals:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTID_MANTIDWIDGETS_IMUONFITFUNCTIONMODEL_H
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/IProjectSaveView.h b/qt/widgets/common/inc/MantidQtWidgets/Common/IProjectSaveView.h
index 40607f947654db6403480029be8c47a78e405611..f107ff82a86b787b039e25be60fad1f523eb0ab9 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/IProjectSaveView.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/IProjectSaveView.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_CUSTOMINTERFACES_IPROJECTSAVEVIEW_H
-#define MANTID_CUSTOMINTERFACES_IPROJECTSAVEVIEW_H
+#pragma once
 
 #include "MantidQtWidgets/Common/IProjectSerialisable.h"
 
@@ -65,5 +64,4 @@ public:
   removeFromExcludedWindowsList(const std::vector<std::string> &windows) = 0;
 };
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /* MANTID_CUSTOMINTERFACES_IPROJECTSAVEVIEW_H */
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/IProjectSerialisable.h b/qt/widgets/common/inc/MantidQtWidgets/Common/IProjectSerialisable.h
index cecf7b68a13a7db73b12008f10984a390ebbb7f5..a7a3a4b025871c575e3af566796201f8d9d5f489 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/IProjectSerialisable.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/IProjectSerialisable.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_API_IProjectSerialisable_H_
-#define MANTID_API_IProjectSerialisable_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 #include <stdexcept>
@@ -51,5 +50,3 @@ public:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif /* MANTID_API_ProjectSerialisable_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/ISlitCalculator.h b/qt/widgets/common/inc/MantidQtWidgets/Common/ISlitCalculator.h
index a56b6caf67f7a26408b62b18b6b5fa12333e9b15..0ae4a8f2f1eafc38e626ec2be10cae1c43beba94 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/ISlitCalculator.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/ISlitCalculator.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_ISLITCALCULATOR_H
-#define MANTID_MANTIDWIDGETS_ISLITCALCULATOR_H
+#pragma once
 
 #include "DllOption.h"
 #include <string>
@@ -21,5 +20,3 @@ public:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTID_MANTIDWIDGETS_ISLITCALCULATOR_H */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/IWorkspaceFitControl.h b/qt/widgets/common/inc/MantidQtWidgets/Common/IWorkspaceFitControl.h
index a1a602feb83bf9ccecf0ba5b37ce0d1f00971dff..5b324e54b1579fe3d268107bda8c5fbfaaa65a3e 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/IWorkspaceFitControl.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/IWorkspaceFitControl.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_IWORKSPACEFITCONTROL_H_
-#define MANTID_MANTIDWIDGETS_IWORKSPACEFITCONTROL_H_
+#pragma once
 
 #include "DllOption.h"
 #include <QString>
@@ -30,5 +29,3 @@ public:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTID_MANTIDWIDGETS_IWORKSPACEFITCONTROL_H_
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/IndirectFitPropertyBrowserLegacy.h b/qt/widgets/common/inc/MantidQtWidgets/Common/IndirectFitPropertyBrowserLegacy.h
index 3a537c1bb1c28277403a74d5c31f3cdc0b08f82a..2c25db839be6fb112075e8ca4182e9b75fcf7b01 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/IndirectFitPropertyBrowserLegacy.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/IndirectFitPropertyBrowserLegacy.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef INDIRECTFITPROPERTYBROWSERLEGACY_H_
-#define INDIRECTFITPROPERTYBROWSERLEGACY_H_
+#pragma once
 
 #include "MantidQtWidgets/Common/FitPropertyBrowser.h"
 #include "MantidQtWidgets/Common/QtPropertyBrowser/qtpropertymanager.h"
@@ -225,5 +224,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*INDIRECTFITPROPERTYBROWSER_H_*/
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/InputController.h b/qt/widgets/common/inc/MantidQtWidgets/Common/InputController.h
index 4ec8a209438f49d6770a2fdc4a04449f6ff02652..fed5fb03a813e70fa70f1cb82381386cf2267daa 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/InputController.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/InputController.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_INPUTCONTROLLER_H
-#define MANTID_MANTIDWIDGETS_INPUTCONTROLLER_H
+#pragma once
 
 #include "DllOption.h"
 #include <QColor>
@@ -306,5 +305,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTID_MANTIDWIDGETS_INPUTCONTROLLER_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/InstrumentSelector.h b/qt/widgets/common/inc/MantidQtWidgets/Common/InstrumentSelector.h
index 1d163d11e5236543db286c8d9a6aa74f43a4ae59..c2a62ba25a7efa05c0f52bfd0207b120840ee8dd 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/InstrumentSelector.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/InstrumentSelector.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_INSTRUMENTSELECTOR_H_
-#define MANTIDQTMANTIDWIDGETS_INSTRUMENTSELECTOR_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidKernel/ConfigService.h"
@@ -100,5 +99,3 @@ private: // members
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQTMANTIDWIDGETS_INSTRUMENTSELECTOR_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/InterfaceManager.h b/qt/widgets/common/inc/MantidQtWidgets/Common/InterfaceManager.h
index c3fbbff516ff7de39bafb442d6d59e3ea384d30f..076b0d579c789870a0a991e23f5838feb5a99adf 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/InterfaceManager.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/InterfaceManager.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_DIALOGMANAGER_H_
-#define MANTIDQT_API_DIALOGMANAGER_H_
+#pragma once
 
 //----------------------------------
 // Includes
@@ -172,4 +171,3 @@ private:
            new Mantid::Kernel::Instantiator<TYPE, MantidHelpInterface>())),    \
        0));                                                                    \
   }
-#endif // MANTIDQT_API_DIALOGMANAGER
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/LineEditWithClear.h b/qt/widgets/common/inc/MantidQtWidgets/Common/LineEditWithClear.h
index 1f2fd5e1db0446969794ef2a3c56db1acedf2434..2b3a0218e9f49cda46a39e7b43843a15f27c7f30 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/LineEditWithClear.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/LineEditWithClear.h
@@ -7,8 +7,7 @@
 **
 ****************************************************************************/
 
-#ifndef LINEEDITWITHCLEAR_H
-#define LINEEDITWITHCLEAR_H
+#pragma once
 
 #include "DllOption.h"
 #include "MantidKernel/System.h"
@@ -36,5 +35,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // LINEEDITWITHCLEAR_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/ListPropertyWidget.h b/qt/widgets/common/inc/MantidQtWidgets/Common/ListPropertyWidget.h
index b7922f7802929e1532b68c472fa60b40ef44f9c4..d0ed25a6342fd22116989d0cda94fc09dcbf893a 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/ListPropertyWidget.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/ListPropertyWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_API_LISTPROPERTYWIDGET_H_
-#define MANTID_API_LISTPROPERTYWIDGET_H_
+#pragma once
 
 #include "MantidKernel/Property.h"
 #include "MantidKernel/System.h"
@@ -42,5 +41,3 @@ protected:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif /* MANTID_API_LISTPROPERTYWIDGET_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/LocalParameterEditor.h b/qt/widgets/common/inc/MantidQtWidgets/Common/LocalParameterEditor.h
index ea161d97356bdd8f63e13bc23e02cf565a154fe7..aafe3bd4fcaa37ed775963e7cb3f03b17d67e939 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/LocalParameterEditor.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/LocalParameterEditor.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDWIDGETS_LOCALPARAMETEREDITOR_H_
-#define MANTIDWIDGETS_LOCALPARAMETEREDITOR_H_
+#pragma once
 
 #include <QWidget>
 
@@ -90,5 +89,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*MANTIDWIDGETS_DATASETPLOTDATA_H_*/
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/LocalParameterItemDelegate.h b/qt/widgets/common/inc/MantidQtWidgets/Common/LocalParameterItemDelegate.h
index 193a4937ad6f1be7771dbecef8fb3820dc5e37f0..f6ea8af406b8d26827c391f2fc9c374d04183afb 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/LocalParameterItemDelegate.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/LocalParameterItemDelegate.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDWIDGETS_LOCALPARAMETERITEMDELEGATE_H_
-#define MANTIDWIDGETS_LOCALPARAMETERITEMDELEGATE_H_
+#pragma once
 
 #include <QStyledItemDelegate>
 
@@ -63,5 +62,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*MANTIDWIDGETS_LOCALPARAMETERITEMDELEGATE_H_*/
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/LogValueFinder.h b/qt/widgets/common/inc/MantidQtWidgets/Common/LogValueFinder.h
index 8c247e00fc932e3b74a27b4c715d99c07c3a6feb..6093610085368e5457b53b39ae1e65adf9209675 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/LogValueFinder.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/LogValueFinder.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGETS_MDFLOGVALUEFINDER_H_
-#define MANTIDQT_MANTIDWIDGETS_MDFLOGVALUEFINDER_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidKernel/Statistics.h"
@@ -39,5 +38,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTIDQT_MANTIDWIDGETS_MDFLOGVALUEFINDER_H_ */
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/LogValueSelector.h b/qt/widgets/common/inc/MantidQtWidgets/Common/LogValueSelector.h
index d0bd854ffe732519c1ea5a9145545070a29223a8..4163a15cbe19ea87e7090b715fdbc530f048f951 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/LogValueSelector.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/LogValueSelector.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGETS_LOGVALUESELECTOR_H_
-#define MANTIDQT_MANTIDWIDGETS_LOGVALUESELECTOR_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidKernel/Statistics.h"
@@ -72,5 +71,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTIDQT_MANTIDWIDGETS_LOGVALUESELECTOR_H_ */
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/MWRunFiles.h b/qt/widgets/common/inc/MantidQtWidgets/Common/MWRunFiles.h
index a74a639124414cd880855537d2ccac73e60f8ce1..bd1a3960f3d0db7566fb4c92808e667541820d73 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/MWRunFiles.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/MWRunFiles.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_MWRUNFILES_H_
-#define MANTIDQTMANTIDWIDGETS_MWRUNFILES_H_
+#pragma once
 
 #include "MantidQtWidgets/Common/DllOption.h"
 #include "MantidQtWidgets/Common/FindFilesThreadPoolManager.h"
@@ -281,5 +280,3 @@ private:
 };
 } // namespace API
 } // namespace MantidQt
-
-#endif // MANTIDQTMANTIDWIDGETS_MWRUNFILES_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/ManageUserDirectories.h b/qt/widgets/common/inc/MantidQtWidgets/Common/ManageUserDirectories.h
index 08df76b19ed3a99c417cb46385a6e6e3053653f6..b7050f4a541a824995fc56a381ff46df50150d33 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/ManageUserDirectories.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/ManageUserDirectories.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANAGE_USER_DIRECTORIES_H
-#define MANTIDQT_MANAGE_USER_DIRECTORIES_H
+#pragma once
 
 #include "DllOption.h"
 #include "MantidQtWidgets/Common/MantidDialog.h"
@@ -50,5 +49,3 @@ private:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif /* MANTIDQT_MANAGE_USER_DIRECTORIES_H */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/MantidAlgorithmMetatype.h b/qt/widgets/common/inc/MantidQtWidgets/Common/MantidAlgorithmMetatype.h
index 6b213d210a6014049eebd3ae815589456e3df271..5b9608cd235afab77c81be6d70478e308f71aec0 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/MantidAlgorithmMetatype.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/MantidAlgorithmMetatype.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDALGORITHMMETATYPE_H
-#define MANTIDALGORITHMMETATYPE_H
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include <QMetaType>
@@ -18,5 +17,3 @@
  */
 
 Q_DECLARE_METATYPE(Mantid::API::IAlgorithm_sptr)
-
-#endif /* MANTIDALGORITHMMETATYPE_H */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/MantidDesktopServices.h b/qt/widgets/common/inc/MantidQtWidgets/Common/MantidDesktopServices.h
index 6fd2c037b2b2a250211dd9df2d7d9701d0ea1242..3d6d02ebb888959754b1ec78aed3ffbe2d76bac7 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/MantidDesktopServices.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/MantidDesktopServices.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_MANTIDDESKTOPSERVICES_H_
-#define MANTIDQT_API_MANTIDDESKTOPSERVICES_H_
+#pragma once
 
 #include "DllOption.h"
 #include <QDesktopServices>
@@ -28,5 +27,3 @@ public:
 };
 } // namespace API
 } // namespace MantidQt
-
-#endif // MANTIDQT_API_MANTIDDESKTOPSERVICES_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/MantidDialog.h b/qt/widgets/common/inc/MantidQtWidgets/Common/MantidDialog.h
index 28284ad99393874e08d97f7bc288c795d1845f56..a59af37b82413a76998dc8b4c0fab1ee6fe60e6b 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/MantidDialog.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/MantidDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_MANTIDDIALOG_H_
-#define MANTIDQT_API_MANTIDDIALOG_H_
+#pragma once
 
 //----------------------------------
 // Includes
@@ -85,5 +84,3 @@ private:
 };
 } // namespace API
 } // namespace MantidQt
-
-#endif // MANTIDQT_API_MANTIDDIALOG_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/MantidDisplayBase.h b/qt/widgets/common/inc/MantidQtWidgets/Common/MantidDisplayBase.h
index e98943a6fdb5be6326aa2e102e430f136c156d34..858086fd7d177e10031e9f60e8262f885d939537 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/MantidDisplayBase.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/MantidDisplayBase.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_MANTIDDISPLAYBASE_H_
-#define MANTID_MANTIDWIDGETS_MANTIDDISPLAYBASE_H_
+#pragma once
 
 #include "MantidAPI/AlgorithmObserver.h"
 #include "MantidAPI/IAlgorithm_fwd.h"
@@ -129,5 +128,4 @@ public:
 #endif
 };
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTID_MANTIDWIDGETS_MANTIDDISPLAYBASE_H_
\ No newline at end of file
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/MantidHelpInterface.h b/qt/widgets/common/inc/MantidQtWidgets/Common/MantidHelpInterface.h
index d9f7f346578624f085022632d01ec9fe96d9731b..1757f4b556419e651635143101210a2a73585375 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/MantidHelpInterface.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/MantidHelpInterface.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_HELPWINDOWINTERFACE_H_
-#define MANTIDQT_API_HELPWINDOWINTERFACE_H_
+#pragma once
 
 #include "DllOption.h"
 #include <QWidget>
@@ -54,5 +53,3 @@ public slots:
 };
 } // namespace API
 } // namespace MantidQt
-
-#endif // MANTIDQT_API_HELPWINDOWINTERFACE_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/MantidHelpWindow.h b/qt/widgets/common/inc/MantidQtWidgets/Common/MantidHelpWindow.h
index fd7751750fba066ece653250b68a078d6098c886..3cc0c5ae05d201d34fadc536af05bb23dd94a9b2 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/MantidHelpWindow.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/MantidHelpWindow.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDHELPWINDOW_H
-#define MANTIDHELPWINDOW_H
+#pragma once
 
 #include "DllOption.h"
 #include "MantidQtWidgets/Common/MantidHelpInterface.h"
@@ -73,5 +72,4 @@ public slots:
 };
 
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDHELPWINDOW_H
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/MantidTreeModel.h b/qt/widgets/common/inc/MantidQtWidgets/Common/MantidTreeModel.h
index c87150a8dab768278f804341af8ad40fac544ed7..380d750a693d59067304641f41a134e1aedd053f 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/MantidTreeModel.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/MantidTreeModel.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGETS_MANTIDTREEMODEL_H
-#define MANTIDQT_MANTIDWIDGETS_MANTIDTREEMODEL_H
+#pragma once
 //----------------------------------
 // Includes
 //----------------------------------
@@ -148,5 +147,4 @@ private:
   MantidTreeModel &operator=(const MantidTreeModel &);
 };
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQT_MANTIDWIDGETS_MANTIDTREEMODEL_H
\ No newline at end of file
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/MantidTreeWidget.h b/qt/widgets/common/inc/MantidQtWidgets/Common/MantidTreeWidget.h
index 047537bd465201e32152764a667213cf831e8d2f..e33fb87f350cf999ef5450e5c7dbfc8f57edf653 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/MantidTreeWidget.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/MantidTreeWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGETS_MANTIDTREEWIDGET_H
-#define MANTIDQT_MANTIDWIDGETS_MANTIDTREEWIDGET_H
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/MatrixWorkspace_fwd.h"
@@ -62,5 +61,4 @@ private:
   Qt::SortOrder m_sortOrder;
 };
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQT_MANTIDWIDGETS_MANTIDTREEWIDGET_H
\ No newline at end of file
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/MantidTreeWidgetItem.h b/qt/widgets/common/inc/MantidQtWidgets/Common/MantidTreeWidgetItem.h
index 5b86f78449e1c6a193e9b39d09026543adc0af5c..7d3c491aba94e6e0c4e16c400e3b8b794e9e09fd 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/MantidTreeWidgetItem.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/MantidTreeWidgetItem.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDTREEWIDGETITEM_H
-#define MANTIDTREEWIDGETITEM_H
+#pragma once
 
 #include "MantidAPI/WorkspaceGroup.h"
 #include "MantidKernel/DateAndTime.h"
@@ -37,5 +36,4 @@ private:
   int m_sortPos;
 };
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDTREEWIDGETITEM_H
\ No newline at end of file
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/MantidWSIndexDialog.h b/qt/widgets/common/inc/MantidQtWidgets/Common/MantidWSIndexDialog.h
index 104d4ba259ef1b5a6c4c1b9c78442081695f7e03..dbe12cbf2f1673900d4754a48b3094ef51fe4fcd 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/MantidWSIndexDialog.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/MantidWSIndexDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDWSINDEXDIALOG_H_
-#define MANTIDWSINDEXDIALOG_H_
+#pragma once
 
 //----------------------------------
 // Includes
@@ -436,5 +435,4 @@ private:
   QVBoxLayout *m_outer;
 };
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDWSINDEXDIALOG_H_
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/MantidWidget.h b/qt/widgets/common/inc/MantidQtWidgets/Common/MantidWidget.h
index 878c5dc9681e2de6d7301c50777e82d18b763704..7b34bc45285b0c4f89be432dfa461ed8251d2efd 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/MantidWidget.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/MantidWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTAPI_MANTIDWIDGET_H_
-#define MANTIDQTAPI_MANTIDWIDGET_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidQtWidgets/Common/PythonRunner.h"
@@ -56,5 +55,3 @@ private:
 };
 } // namespace API
 } // namespace MantidQt
-
-#endif // MANTIDQTAPI_MANTIDWIDGET_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/MdConstants.h b/qt/widgets/common/inc/MantidQtWidgets/Common/MdConstants.h
index 5903ff7165ff71012ad4bd3ef73fdbb21e462b34..cae58f8f067860618cb597706a2efdbe73e554a2 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/MdConstants.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/MdConstants.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MDCONSTANTS_H_
-#define MDCONSTANTS_H_
+#pragma once
 
 #include "DllOption.h"
 #include <QColor>
@@ -86,5 +85,3 @@ private:
 };
 } // namespace API
 } // namespace MantidQt
-
-#endif
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/MdSettings.h b/qt/widgets/common/inc/MantidQtWidgets/Common/MdSettings.h
index 726e59bc79d18fd172f7a4a65da3ed2ee00e540b..478f4e09203dba1cf40035d8233f36d51d845fe3 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/MdSettings.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/MdSettings.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MDSETTINGS_H_
-#define MDSETTINGS_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidQtWidgets/Common/MdConstants.h"
@@ -178,5 +177,3 @@ private:
 };
 } // namespace API
 } // namespace MantidQt
-
-#endif
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Message.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Message.h
index 366567d53e59beed7afa322212925f7d6f271860..633d92291b62d754928a8ab6464b3a24afd9a0c9 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Message.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Message.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MESSAGE_H_
-#define MESSAGE_H_
+#pragma once
 
 //----------------------------------
 // Includes
@@ -71,5 +70,3 @@ private:
 
 /// Required to operate in signals/slots
 Q_DECLARE_METATYPE(MantidQt::MantidWidgets::Message)
-
-#endif // MESSAGE_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/MessageDisplay.h b/qt/widgets/common/inc/MantidQtWidgets/Common/MessageDisplay.h
index d9e2d14005cb744aaeb5c93928ebb14be6805029..f2202724127095b9fe8fe5be74703b40e3dc4dfe 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/MessageDisplay.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/MessageDisplay.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MESSAGEDISPLAY_H_
-#define MESSAGEDISPLAY_H_
+#pragma once
 
 //----------------------------------
 // Includes
@@ -188,5 +187,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MESSAGEDISPLAY_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/MockAlgorithmRunner.h b/qt/widgets/common/inc/MantidQtWidgets/Common/MockAlgorithmRunner.h
index 6dbf00d84ddd7685f526299dcaf6c11842ed3f3a..466354c1227609806ef9a92f4820f0e08e146c8b 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/MockAlgorithmRunner.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/MockAlgorithmRunner.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGETS_MOCKALGORITHMRUNNER_H
-#define MANTIDQT_MANTIDWIDGETS_MOCKALGORITHMRUNNER_H
+#pragma once
 
 #include "MantidAPI/IAlgorithm_fwd.h"
 #include "MantidKernel/WarningSuppressions.h"
@@ -38,5 +37,3 @@ private:
 };
 
 GNU_DIAG_ON_SUGGEST_OVERRIDE
-
-#endif
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/MockProgressableView.h b/qt/widgets/common/inc/MantidQtWidgets/Common/MockProgressableView.h
index 5c2618cb6c14945de8ccbee63a7818b51cfacd48..77b7513802a609f62ea9317cca61fe599b522792 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/MockProgressableView.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/MockProgressableView.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_MOCKPROGRESSABLEVIEW_H
-#define MANTID_MANTIDWIDGETS_MOCKPROGRESSABLEVIEW_H
+#pragma once
 
 #include "MantidKernel/WarningSuppressions.h"
 #include "MantidQtWidgets/Common/ProgressableView.h"
@@ -25,5 +24,3 @@ public:
   MOCK_METHOD0(setAsEndlessIndicator, void());
   GNU_DIAG_ON_SUGGEST_OVERRIDE
 };
-
-#endif /* MANTID_MANTIDWIDGETS_MOCKPROGRESSABLEVIEW_H */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/MockSlitCalculator.h b/qt/widgets/common/inc/MantidQtWidgets/Common/MockSlitCalculator.h
index 2a0dc11605066258fcb8748fc9f1eeea5fb42f16..9cd7cca8fef4d1cdfba5eb23dea74df04d472ca5 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/MockSlitCalculator.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/MockSlitCalculator.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_MOCKSLITCALCULATOR_H
-#define MANTID_MANTIDWIDGETS_MOCKSLITCALCULATOR_H
+#pragma once
 
 #include "ISlitCalculator.h"
 #include <gmock/gmock.h>
@@ -19,5 +18,3 @@ public:
   MOCK_METHOD0(show, void());
   GNU_DIAG_ON_SUGGEST_OVERRIDE
 };
-
-#endif /* MANTID_MANTIDWIDGETS_MOCKSLITCALCULATOR_H */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/MultifitSetupDialog.h b/qt/widgets/common/inc/MantidQtWidgets/Common/MultifitSetupDialog.h
index 1f55503efd601358d43a4e0d82f364e7062607a9..94fbff4bbf2aab4101ca63c6bd175aa939c70a5c 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/MultifitSetupDialog.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/MultifitSetupDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MULTIFITSETUPTDIALOG_H
-#define MULTIFITSETUPTDIALOG_H
+#pragma once
 
 #include "ui_MultifitSetupDialog.h"
 #include <QDialog>
@@ -49,5 +48,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MULTIFITSETUPTDIALOG_H */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/MuonFitDataSelector.h b/qt/widgets/common/inc/MantidQtWidgets/Common/MuonFitDataSelector.h
index 9ca2687842d8bb4bd58e44f7ba2d5f573a6f2a63..9ae3c4e23900b5475b54248817309f7d3ca5c1c5 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/MuonFitDataSelector.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/MuonFitDataSelector.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_MUONFITDATASELECTOR_H_
-#define MANTID_MANTIDWIDGETS_MUONFITDATASELECTOR_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidQtWidgets/Common/FitPropertyBrowser.h"
@@ -130,5 +129,3 @@ private slots:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTID_MANTIDWIDGETS_MUONFITDATASELECTOR_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/MuonFitPropertyBrowser.h b/qt/widgets/common/inc/MantidQtWidgets/Common/MuonFitPropertyBrowser.h
index 38d8ef0fccadb0a853e826aadd467f93ef6445f1..0e4a707b80e3811bf433e1611a49bb49941c0070 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/MuonFitPropertyBrowser.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/MuonFitPropertyBrowser.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MUONFITPROPERTYBROWSER_H_
-#define MUONFITPROPERTYBROWSER_H_
+#pragma once
 
 #include "MantidQtWidgets/Common/FitPropertyBrowser.h"
 #include "MantidQtWidgets/Common/IMuonFitDataModel.h"
@@ -251,5 +250,3 @@ private:
 std::map<std::string, double> readMultipleNormalization();
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*MUONFITPROPERTYBROWSER_H_*/
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/MuonFunctionBrowser.h b/qt/widgets/common/inc/MantidQtWidgets/Common/MuonFunctionBrowser.h
index 27910ff93660ce83100d04fae6e84e2b54d7153f..1f3a55b571cb29d281493303ec6b2aa70ffac240 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/MuonFunctionBrowser.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/MuonFunctionBrowser.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_MUONFUNCTIONBROWSER_H_
-#define MANTID_MANTIDWIDGETS_MUONFUNCTIONBROWSER_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidQtWidgets/Common/FunctionBrowser.h"
@@ -27,5 +26,3 @@ public:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTID_MANTIDWIDGETS_MUONFUNCTIONBROWSER_H_ */
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/NonOrthogonal.h b/qt/widgets/common/inc/MantidQtWidgets/Common/NonOrthogonal.h
index 7c6799e420c45ba51217b36fc6d9adfca3ad3640..6037d3637bd85b7ea441425fa970500ec8f55f96 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/NonOrthogonal.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/NonOrthogonal.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDQT_API_NON_ORTHOGONAL_H_
-#define MANTID_MANTIDQT_API_NON_ORTHOGONAL_H_
+#pragma once
 
 #include "MantidAPI/IMDWorkspace.h"
 #include "MantidKernel/Matrix.h"
@@ -65,5 +64,3 @@ getGridLineAnglesInRadian(const std::array<Mantid::coord_t, 9> &skewMatrixCoord,
                           size_t dimX, size_t dimY);
 } // namespace API
 } // namespace MantidQt
-
-#endif
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/NotificationService.h b/qt/widgets/common/inc/MantidQtWidgets/Common/NotificationService.h
index 8a16b1f3ec18de7808670c8c8fbb6b377a984fc8..561a08ca95be6a31e512341f182cf82dd5e9cc79 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/NotificationService.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/NotificationService.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTAPI_NOTIFICATIONSERVICE_H_
-#define MANTIDQTAPI_NOTIFICATIONSERVICE_H_
+#pragma once
 
 #include "DllOption.h"
 #include <QObject>
@@ -59,5 +58,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQTAPI_NOTIFICATIONSERVICE_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/ObserverPattern.h b/qt/widgets/common/inc/MantidQtWidgets/Common/ObserverPattern.h
index 4bd753a81eefb6a236a5ac9d5ef1da746aa9a02c..bfa5b26fca06ad727e58c376f1bf7faffc42f0e8 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/ObserverPattern.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/ObserverPattern.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_CUSTOMINTERFACES_OBSERVERPATTERN_H_
-#define MANTIDQT_CUSTOMINTERFACES_OBSERVERPATTERN_H_
+#pragma once
 #include <functional>
 #include <set>
 #include <string>
@@ -72,5 +71,3 @@ public:
 private:
   std::function<void()> m_slot;
 };
-
-#endif /* MANTIDQT_CUSTOMINTERFACES_OBSERVERPATTERN_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/OptionsPropertyWidget.h b/qt/widgets/common/inc/MantidQtWidgets/Common/OptionsPropertyWidget.h
index 4da25b98f2570d2e15e62b4095dd5f3bf342ba88..81301519b85820f11645f0d1562a9817a718e192 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/OptionsPropertyWidget.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/OptionsPropertyWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_API_OPTIONSPROPERTYWIDGET_H_
-#define MANTID_API_OPTIONSPROPERTYWIDGET_H_
+#pragma once
 
 #include "MantidKernel/Property.h"
 #include "MantidKernel/System.h"
@@ -45,5 +44,3 @@ protected:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif /* MANTID_API_OPTIONSPROPERTYWIDGET_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/ParseKeyValueString.h b/qt/widgets/common/inc/MantidQtWidgets/Common/ParseKeyValueString.h
index e9d6703158475f8e4398def08bac871716be5779..a369df47983c2a78947c6a2086bb67a3b07707f7 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/ParseKeyValueString.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/ParseKeyValueString.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_PARSEKEYVALUESTRING_H
-#define MANTIDQTMANTIDWIDGETS_PARSEKEYVALUESTRING_H
+#pragma once
 
 /** parseKeyValueString
 
@@ -44,5 +43,3 @@ std::string EXPORT_OPT_MANTIDQT_COMMON optionsToString(
     const bool quoteValues = true, const std::string &separator = ", ");
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQTMANTIDWIDGETS_PARSEKEYVALUESTRING_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/ParseNumerics.h b/qt/widgets/common/inc/MantidQtWidgets/Common/ParseNumerics.h
index 51582bc4ac7b05b88d10ed3a21d4527edadfadf4..1853da2d35b1e6e1014e18320d402a90d9f8e540 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/ParseNumerics.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/ParseNumerics.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_DATAPOCESSORPARSENUMERICS_H
-#define MANTID_MANTIDWIDGETS_DATAPOCESSORPARSENUMERICS_H
+#pragma once
 #include "MantidQtWidgets/Common/DllOption.h"
 #include <QString>
 /**
@@ -20,5 +19,4 @@ double EXPORT_OPT_MANTIDQT_COMMON parseDouble(QString const &in);
 /// Converts a string denoting a denary integer to it
 int EXPORT_OPT_MANTIDQT_COMMON parseDenaryInteger(QString const &in);
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTID_MANTIDWIDGETS_DATAPOCESSORPARSENUMERICS_H
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/PlotAxis.h b/qt/widgets/common/inc/MantidQtWidgets/Common/PlotAxis.h
index 733fc66c9b7b9b1937ff34969304b5424790cbae..7613ed597ea174741346273e5578fae89bc8b4f2 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/PlotAxis.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/PlotAxis.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_PLOTAXISLABEL_H_
-#define MANTIDQT_API_PLOTAXISLABEL_H_
+#pragma once
 
 #include "MantidAPI/IMDWorkspace.h"
 #include "MantidAPI/MatrixWorkspace_fwd.h"
@@ -55,5 +54,3 @@ private:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif /* MANTIDQT_API_PLOTAXISLABEL_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/PluginLibraries.h b/qt/widgets/common/inc/MantidQtWidgets/Common/PluginLibraries.h
index 9eae016a648f0a3e92594c5b876a05cc4626fb31..b895f0c8c173c0cd64b6d4f81926a0725f55bdd5 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/PluginLibraries.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/PluginLibraries.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_WIDGETS_COMMON_PLUGINLIBRARIES_H
-#define MANTIDQT_WIDGETS_COMMON_PLUGINLIBRARIES_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DllOption.h"
 
@@ -23,5 +22,3 @@ EXPORT_OPT_MANTIDQT_COMMON int loadPluginsFromCfgPath(std::string key);
 EXPORT_OPT_MANTIDQT_COMMON int loadPluginsFromPath(std::string path);
 } // namespace API
 } // namespace MantidQt
-
-#endif // PLUGINLIBRARYLOADER_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/PrecompiledHeader.h b/qt/widgets/common/inc/MantidQtWidgets/Common/PrecompiledHeader.h
index 8e8a0c60f24a37fcad979493e60f9fa8a3e68c68..e163b14143c4ad0d705c9f49d17be9d1e204a89e 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/PrecompiledHeader.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/PrecompiledHeader.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_PRECOMPILEDHEADER_H_
-#define MANTIDQT_API_PRECOMPILEDHEADER_H_
+#pragma once
 
 // Mantid
 #include "MantidAPI/Algorithm.h"
@@ -17,5 +16,3 @@
 #include <set>
 #include <string>
 #include <vector>
-
-#endif // MANTIDQT_API_PRECOMPILEDHEADER_H_
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/ProcessingAlgoWidget.h b/qt/widgets/common/inc/MantidQtWidgets/Common/ProcessingAlgoWidget.h
index c8ae7e5be8f7df990418e1cca36a05f3c79875dc..12dd8d97eef2b0ce421a8a0b3dbf07c3545fc99e 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/ProcessingAlgoWidget.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/ProcessingAlgoWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDWIDGETS_PROCESSINGALGOWIDGET_H_
-#define MANTIDWIDGETS_PROCESSINGALGOWIDGET_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidAPI/Algorithm.h"
@@ -92,5 +91,4 @@ private:
 };
 
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/ProgressPresenter.h b/qt/widgets/common/inc/MantidQtWidgets/Common/ProgressPresenter.h
index e0f4dfd45319eef549a13bca97179e07b04e8151..aa2a3fba136f62a4d0b4bbecda98e1096515ad4f 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/ProgressPresenter.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/ProgressPresenter.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_PROGRESSPRESENTER_H
-#define MANTIDQTMANTIDWIDGETS_PROGRESSPRESENTER_H
+#pragma once
 
 #include "MantidKernel/ProgressBase.h"
 #include "MantidQtWidgets/Common/ProgressableView.h"
@@ -39,5 +38,4 @@ public:
   }
   void setAsEndlessIndicator() { m_progressableView->setAsEndlessIndicator(); }
   ~ProgressPresenter() {}
-};
-#endif /* MANTIDQTMANTIDWIDGETS_PROGRESSPRESENTER_H */
+};
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/ProgressableView.h b/qt/widgets/common/inc/MantidQtWidgets/Common/ProgressableView.h
index 60eee7fa240fe0f67b569c0ae8ee61d6c3e17166..38fedbdeb7a8edece0e75349403d7d75f49b63b2 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/ProgressableView.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/ProgressableView.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_PROGRESSABLEVIEW_H_
-#define MANTIDQTMANTIDWIDGETS_PROGRESSABLEVIEW_H_
+#pragma once
 
 #include "MantidQtWidgets/Common/DllOption.h"
 
@@ -39,5 +38,3 @@ protected:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTIDQTMANTIDWIDGETS_PROGRESSABLEVIEW_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/ProjectSaveModel.h b/qt/widgets/common/inc/MantidQtWidgets/Common/ProjectSaveModel.h
index f3a5d40afe2d6fc4308d0fe63e4096bb696b7937..5444574a027aba3b9075fc981c4a6cf39a1a69f0 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/ProjectSaveModel.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/ProjectSaveModel.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGETS_PROJECTSAVEMODEL_H
-#define MANTIDQT_MANTIDWIDGETS_PROJECTSAVEMODEL_H
+#pragma once
 
 #include "MantidAPI/Workspace.h"
 #include "MantidQtWidgets/Common/IProjectSerialisable.h"
@@ -99,5 +98,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQT_MANTIDWIDGETS_PROJECTSAVEMODEL_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/ProjectSavePresenter.h b/qt/widgets/common/inc/MantidQtWidgets/Common/ProjectSavePresenter.h
index c3d4fa31c333cb6e46b8a15bb43a70993e83d238..a1290a64ecdbc3f091cdd230990b537b30873b67 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/ProjectSavePresenter.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/ProjectSavePresenter.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGETS_PROJECTSAVEPRESENTER_H
-#define MANTIDQT_MANTIDWIDGETS_PROJECTSAVEPRESENTER_H
+#pragma once
 
 #include "MantidAPI/Workspace.h"
 #include "MantidQtWidgets/Common/IProjectSaveView.h"
@@ -56,5 +55,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // PROJECTSAVEPRESENTER_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/PropertyHandler.h b/qt/widgets/common/inc/MantidQtWidgets/Common/PropertyHandler.h
index 5a350326a8c4a92635977c03ab3c125bac5f6a38..d786af57fa4af160920c5011c8fe95b0bf7b1759 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/PropertyHandler.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/PropertyHandler.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef PROPERTY_HANDLER_H
-#define PROPERTY_HANDLER_H
+#pragma once
 
 #include "DllOption.h"
 #include "MantidAPI/IFunction.h"
@@ -276,5 +275,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* PROPERTY_HANDLER_H */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/PropertyWidget.h b/qt/widgets/common/inc/MantidQtWidgets/Common/PropertyWidget.h
index 8cb33b0674442b26e1a833b2be40322094141569..5a6c07edca66b3fd5eb60abad60579f9e81fc521 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/PropertyWidget.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/PropertyWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_API_PROPERTYWIDGET_H_
-#define MANTID_API_PROPERTYWIDGET_H_
+#pragma once
 
 #include "MantidKernel/Property.h"
 #include "MantidKernel/System.h"
@@ -171,5 +170,3 @@ protected:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif /* MANTID_API_PROPERTYWIDGET_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/PropertyWidgetFactory.h b/qt/widgets/common/inc/MantidQtWidgets/Common/PropertyWidgetFactory.h
index 96759c1c9919b88f473bea2583d3e18c1fbf5d99..a37ab75e1e23c690ea1206895a5dfbb509655349 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/PropertyWidgetFactory.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/PropertyWidgetFactory.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_API_PROPERTYWIDGETFACTORY_H_
-#define MANTID_API_PROPERTYWIDGETFACTORY_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 
@@ -38,5 +37,3 @@ public:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif /* MANTID_API_PROPERTYWIDGETFACTORY_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Python/CodeExecution.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Python/CodeExecution.h
index 444795d16a8fe6e001b74538d0f31bced0b8f61f..7d43bcecab10b1f9c4e84f4c37f8fea59fd43486 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Python/CodeExecution.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Python/CodeExecution.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTWIDGETS_LINETRACKINGEXECUTOR_H
-#define MANTIDQTWIDGETS_LINETRACKINGEXECUTOR_H
+#pragma once
 
 #include "MantidPythonInterface/core/WrapPython.h"
 #include "MantidQtWidgets/Common/DllOption.h"
@@ -31,5 +30,3 @@ private:
 };
 
 } // namespace MantidQt::Widgets::Common::Python
-
-#endif // MANTIDQTWIDGETS_LINETRACKINGEXECUTOR_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Python/Object.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Python/Object.h
index 8f1ac425e762d57ef8d507d8884d5460819c23e8..dd91c128f25e9607dd3bb502e085ab29c2e1c6e1 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Python/Object.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Python/Object.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTWIDGETS_PYTHON_OBJECT_H
-#define MANTIDQTWIDGETS_PYTHON_OBJECT_H
+#pragma once
 
 #include "MantidPythonInterface/core/ErrorHandling.h"
 #include "MantidPythonInterface/core/GlobalInterpreterLock.h"
@@ -105,5 +104,3 @@ private:
 } // namespace Common
 } // namespace Widgets
 } // namespace MantidQt
-
-#endif // MANTIDQTWIDGETS_PYTHON_OBJECT_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Python/QHashToDict.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Python/QHashToDict.h
index 4e2170e965259174fe1668970303dd6cab4cb460..642f324e17d1d3c4efff7dcc7b9327393e5d41b5 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Python/QHashToDict.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Python/QHashToDict.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTWIDGETS_QHASHTODICT_H
-#define MANTIDQTWIDGETS_QHASHTODICT_H
+#pragma once
 #include "MantidQtWidgets/Common/DllOption.h"
 #include "MantidQtWidgets/Common/Python/Object.h"
 
@@ -25,5 +24,3 @@ EXPORT_OPT_MANTIDQT_COMMON Python::Dict qHashToDict(const KwArgs &hash);
 } // namespace Common
 } // namespace Widgets
 } // namespace MantidQt
-
-#endif /* MANTIDQTWIDGETS_QHASHTODICT_H */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Python/Sip.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Python/Sip.h
index 08ec5f0b67a0d28846501126b306f301614c62ba..4ce163728c9d851eb1b175883fec29d9108053df 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Python/Sip.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Python/Sip.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTWIDGETS_SIPUTILS_H
-#define MANTIDQTWIDGETS_SIPUTILS_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DllOption.h"
 #include "MantidQtWidgets/Common/Python/Object.h"
@@ -48,5 +47,3 @@ template <typename T> T *extract(const Object &obj) {
 } // namespace Widgets
 
 } // namespace MantidQt
-
-#endif // MPLCPP_SIPUTILS_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/PythonRunner.h b/qt/widgets/common/inc/MantidQtWidgets/Common/PythonRunner.h
index 057afdfa2d120d8e010b59bf271d2a16cfa87e02..a388786b9e55ebf376a52b7fd9aa5fa5de2043f6 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/PythonRunner.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/PythonRunner.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTAPI_PYTHONRUNNER_H_
-#define MANTIDQTAPI_PYTHONRUNNER_H_
+#pragma once
 
 #include "DllOption.h"
 #include <QObject>
@@ -40,5 +39,3 @@ signals:
 };
 } // namespace API
 } // namespace MantidQt
-
-#endif // MANTIDQTAPI_PYTHONRUNNER_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/QScienceSpinBox.h b/qt/widgets/common/inc/MantidQtWidgets/Common/QScienceSpinBox.h
index ab71fef3b499b25ebcc57b6ebdfa88c7edbb16a6..233a2fc7ec1612d9740b19f6f9c6358cdca81ea5 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/QScienceSpinBox.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/QScienceSpinBox.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_QSCIENCESPINBOX_H_
-#define MANTIDQT_API_QSCIENCESPINBOX_H_
+#pragma once
 
 #include "MantidQtWidgets/Common/DllOption.h"
 
@@ -59,5 +58,4 @@ signals:
 };
 
 } // namespace API
-} // namespace MantidQt
-#endif /* MANTIDQT_API_QSCIENCESPINBOX_H_ */
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/QStringUtils.h b/qt/widgets/common/inc/MantidQtWidgets/Common/QStringUtils.h
index 21db08acdec61032a4a01b0e6c20f7ef105c02a2..4f8308b13b15b192de6ba17dae98279bf52fe244 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/QStringUtils.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/QStringUtils.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_QSTRINGUTILS_H
-#define MANTIDQT_API_QSTRINGUTILS_H
+#pragma once
 
 #include <QString>
 #include <string>
@@ -43,5 +42,3 @@ inline QString toQStringInternal(const std::wstring &str) {
 }
 } // namespace API
 } // namespace MantidQt
-
-#endif // MANTIDQT_API_QSTRINGUTILS_H
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/QtJSONUtils.h b/qt/widgets/common/inc/MantidQtWidgets/Common/QtJSONUtils.h
index 36e0748ee2838725c3aec41bd0680aa68aa4e3d1..8900d00d7d7af95ee3eb7ba4222294e76995994b 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/QtJSONUtils.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/QtJSONUtils.h
@@ -5,8 +5,7 @@
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
 
-#ifndef MANTIDQT_API_QJSONUTILS_H
-#define MANTIDQT_API_QJSONUTILS_H
+#pragma once
 
 #include "DllOption.h"
 
@@ -29,5 +28,3 @@ QMap<QString, QVariant>
 
 } // namespace API
 } // namespace MantidQt
-
-#endif /* MANTIDQT_API_QJSONUTILS_H */
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/ButtonEditorFactory.h b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/ButtonEditorFactory.h
index 47f17d42ff807ee52fa3af2b634ab1e52bceef8f..9f51ad04bd4d0709c02f76a92e9dbe0dbaa1aaee 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/ButtonEditorFactory.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/ButtonEditorFactory.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef BUTTONEDITORFACTORY_H
-#define BUTTONEDITORFACTORY_H
+#pragma once
 
 #include "ParameterPropertyManager.h"
 #include "qtpropertymanager.h"
@@ -66,5 +65,3 @@ public:
 Q_SIGNALS:
   void buttonClicked(QtProperty * /*_t1*/);
 };
-
-#endif // BUTTONEDITORFACTORY_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/CompositeEditorFactory.h b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/CompositeEditorFactory.h
index 48b58d213505b2c2205aaed6c8181c0d7e2d46cf..af8ffddc090f68cc70c75626f86552b91dfb73d8 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/CompositeEditorFactory.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/CompositeEditorFactory.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef COMPOSITEEDITORFACTORY_H
-#define COMPOSITEEDITORFACTORY_H
+#pragma once
 
 #include "qtpropertybrowser.h"
 #include <QPushButton>
@@ -64,5 +63,3 @@ private:
   FactoryBaseType *m_secondaryFactory;
   QString m_optionName;
 };
-
-#endif // COMPOSITEEDITORFACTORY_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/DoubleDialogEditor.h b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/DoubleDialogEditor.h
index 3b8aaff9472ccafcc6dc3c5eaae4467d73019188..464fb05f901cc03077bc666f8b7c189e6408b892 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/DoubleDialogEditor.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/DoubleDialogEditor.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DOUBLEDIALOGEDITORFACTORY_H
-#define DOUBLEDIALOGEDITORFACTORY_H
+#pragma once
 
 #include "DoubleEditorFactory.h"
 #include "ParameterPropertyManager.h"
@@ -79,5 +78,3 @@ protected:
   disconnectPropertyManager(ParameterPropertyManager * /*manager*/) override {}
   bool m_hasOption;
 };
-
-#endif // DOUBLEDIALOGEDITORFACTORY_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/DoubleEditorFactory.h b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/DoubleEditorFactory.h
index 0c7054b9f74976823e37cbdf8a48192a501f8630..f05a2fd68a6f35a67b252cfad99cfb1a8820dae2 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/DoubleEditorFactory.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/DoubleEditorFactory.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DOUBLEEDITORFACTORY_H
-#define DOUBLEEDITORFACTORY_H
+#pragma once
 
 #include "ParameterPropertyManager.h"
 #include "qtpropertymanager.h"
@@ -101,5 +100,3 @@ public:
       : DoubleEditorFactoryBase<ParameterPropertyManager, ParameterEditor>(
             parent) {}
 };
-
-#endif // DOUBLEEDITORFACTORY_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/FilenameDialogEditor.h b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/FilenameDialogEditor.h
index f52bfc32107d41c0f080dd628581515113114884..e6795ba1e36411e272d75f28b8ec3a2666882785 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/FilenameDialogEditor.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/FilenameDialogEditor.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGETS_FILENAMEDIALOGEDITFACTORY_H
-#define MANTIDQT_MANTIDWIDGETS_FILENAMEDIALOGEDITFACTORY_H
+#pragma once
 
 #include "StringDialogEditor.h"
 
@@ -45,5 +44,3 @@ protected:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQT_MANTIDWIDGETS_FILENAMEDIALOGEDITFACTORY_H
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/FormulaDialogEditor.h b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/FormulaDialogEditor.h
index 08605ec3a6141bc2fbf1d6d1944655cd9708deea..352dcda7ac16779a375e08de39705f0e7d8f863a 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/FormulaDialogEditor.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/FormulaDialogEditor.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGETS_FORMULADIALOGEDIT_H
-#define MANTIDQT_MANTIDWIDGETS_FORMULADIALOGEDIT_H
+#pragma once
 
 #include "StringDialogEditor.h"
 
@@ -42,5 +41,3 @@ protected:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQT_MANTIDWIDGETS_FORMULADIALOGEDIT_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/ParameterPropertyManager.h b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/ParameterPropertyManager.h
index bb52d3b27834dc626790daddfdd61ca43dadb602..fd61738a07a349d9d0c914c36fa582fc5a692eaf 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/ParameterPropertyManager.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/ParameterPropertyManager.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef PARAMETERPROPERTYMANAGER_H
-#define PARAMETERPROPERTYMANAGER_H
+#pragma once
 
 #include "qtpropertymanager.h"
 
@@ -85,5 +84,3 @@ private:
   bool m_hasGlobalOption;
   QSet<QtProperty *> m_globals;
 };
-
-#endif // PARAMETERPROPERTYMANAGER_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/StringDialogEditor.h b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/StringDialogEditor.h
index ed224078c81f03513859fcdbea48bf171c6016ca..2679ac1304d2c8a48fce9b4691c7d14296049386 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/StringDialogEditor.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/StringDialogEditor.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef STRINGDIALOGEDITORFACTORY_H
-#define STRINGDIALOGEDITORFACTORY_H
+#pragma once
 
 #include "qtpropertymanager.h"
 
@@ -56,5 +55,3 @@ private:
   QLineEdit *m_lineEdit;
   QtProperty *m_property;
 };
-
-#endif // STRINGDIALOGEDITORFACTORY_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/StringEditorFactory.h b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/StringEditorFactory.h
index d20a6efdf67fcbc11dd2d28109095061820db3b5..64a20f527577a6bd6c91dd013f74e60558512114 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/StringEditorFactory.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/StringEditorFactory.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef STRINGEDITORFACTORY_H
-#define STRINGEDITORFACTORY_H
+#pragma once
 
 #include "qtpropertymanager.h"
 #include <QLineEdit>
@@ -38,5 +37,3 @@ protected slots:
 private:
   QtProperty *m_property;
 };
-
-#endif // STRINGEDITORFACTORY_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/WorkspaceEditorFactory.h b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/WorkspaceEditorFactory.h
index 1bad7304688148820c170dfe60858623f81a1663..1e25c1c9ba6c2731c07b3ea3e19400236168e35f 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/WorkspaceEditorFactory.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/WorkspaceEditorFactory.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef STRINGEDITORFACTORY_H
-#define STRINGEDITORFACTORY_H
+#pragma once
 
 #include "MantidQtWidgets/Common/QtPropertyBrowser/qtpropertymanager.h"
 #include "MantidQtWidgets/Common/WorkspaceSelector.h"
@@ -45,5 +44,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // STRINGEDITORFACTORY_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qtbuttonpropertybrowser.h b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qtbuttonpropertybrowser.h
index d4a89718f22ad741784bfdb9807caf6b8c80368b..5ff81e339a940392d52e15701224a97b5943a3c9 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qtbuttonpropertybrowser.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qtbuttonpropertybrowser.h
@@ -85,8 +85,7 @@
 **
 ****************************************************************************/
 
-#ifndef QTBUTTONPROPERTYBROWSER_H
-#define QTBUTTONPROPERTYBROWSER_H
+#pragma once
 
 #include "qtpropertybrowser.h"
 #include <QMap>
@@ -186,5 +185,3 @@ private:
 #if QT_VERSION >= 0x040400
 QT_END_NAMESPACE
 #endif
-
-#endif
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qteditorfactory.h b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qteditorfactory.h
index b9e1fb143f7dae19184f73161de040c4cb5c1d0e..099e3ede4007423f915bcf5f3979b27082ac925f 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qteditorfactory.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qteditorfactory.h
@@ -85,8 +85,7 @@
 **
 ****************************************************************************/
 
-#ifndef QTEDITORFACTORY_H
-#define QTEDITORFACTORY_H
+#pragma once
 
 #include "qtpropertybrowserutils_p.h"
 #include "qtpropertymanager.h"
@@ -800,5 +799,3 @@ public:
 #if QT_VERSION >= 0x040400
 QT_END_NAMESPACE
 #endif
-
-#endif
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qtgroupboxpropertybrowser.h b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qtgroupboxpropertybrowser.h
index 7c6106190f30b17aef86d5829ed1330eb2681a44..236860a2cca659f9515da2d036cfe99a37cea315 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qtgroupboxpropertybrowser.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qtgroupboxpropertybrowser.h
@@ -85,8 +85,7 @@
 **
 ****************************************************************************/
 
-#ifndef QTGROUPBOXPROPERTYBROWSER_H
-#define QTGROUPBOXPROPERTYBROWSER_H
+#pragma once
 
 #include "qtpropertybrowser.h"
 #include <QMap>
@@ -170,5 +169,3 @@ private:
 #if QT_VERSION >= 0x040400
 QT_END_NAMESPACE
 #endif
-
-#endif
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qtpropertybrowser.h b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qtpropertybrowser.h
index a94fc4a01db92bdd16b2713ef23dccbdb64c8bb6..38b29187e8d3dde6861a462964d07db19ac31c3a 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qtpropertybrowser.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qtpropertybrowser.h
@@ -85,8 +85,7 @@
 **
 ****************************************************************************/
 
-#ifndef QTPROPERTYBROWSER_H
-#define QTPROPERTYBROWSER_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DllOption.h"
 #include <QMap>
@@ -423,5 +422,3 @@ public:
 #if QT_VERSION >= 0x040400
 QT_END_NAMESPACE
 #endif
-
-#endif // QTPROPERTYBROWSER_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qtpropertybrowserutils_p.h b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qtpropertybrowserutils_p.h
index 7437441efbcc1d5813f0a0bc7d947ec2b59a9a85..39f0522746e15312802508b4fcf4bec6a0567f7d 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qtpropertybrowserutils_p.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qtpropertybrowserutils_p.h
@@ -96,8 +96,7 @@
 // We mean it.
 //
 
-#ifndef QTPROPERTYBROWSERUTILS_H
-#define QTPROPERTYBROWSERUTILS_H
+#pragma once
 
 #include <QIcon>
 #include <QMap>
@@ -204,5 +203,3 @@ private:
 #if QT_VERSION >= 0x040400
 QT_END_NAMESPACE
 #endif
-
-#endif
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qtpropertymanager.h b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qtpropertymanager.h
index dedd26e011df9c2caf797b1a86ad8d050a314540..a5e5e7b40eb238d7b5dbce1ecf7ba391d3270167 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qtpropertymanager.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qtpropertymanager.h
@@ -85,8 +85,7 @@
 **
 ****************************************************************************/
 
-#ifndef QTPROPERTYMANAGER_H
-#define QTPROPERTYMANAGER_H
+#pragma once
 
 #include "qtpropertybrowser.h"
 
@@ -1504,5 +1503,3 @@ private:
 #if QT_VERSION >= 0x040400
 QT_END_NAMESPACE
 #endif
-
-#endif
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qttreepropertybrowser.h b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qttreepropertybrowser.h
index 26f669ffee991ae8b40f97c3f4fb2d39e74bc707..cfe2db199c5f9e2d053b5c953ef32f3730a44827 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qttreepropertybrowser.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qttreepropertybrowser.h
@@ -85,8 +85,7 @@
 **
 ****************************************************************************/
 
-#ifndef QTTREEPROPERTYBROWSER_H
-#define QTTREEPROPERTYBROWSER_H
+#pragma once
 
 #include "qtpropertybrowser.h"
 
@@ -383,5 +382,3 @@ private:
 #if QT_VERSION >= 0x040400
 QT_END_NAMESPACE
 #endif
-
-#endif
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qtvariantproperty.h b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qtvariantproperty.h
index f54dce9beb2fd2d383d7737e4f2de062b7ffff06..2e20706f693c9db6208428b2f169cfa11dc3374f 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qtvariantproperty.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/QtPropertyBrowser/qtvariantproperty.h
@@ -85,8 +85,7 @@
 **
 ****************************************************************************/
 
-#ifndef QTVARIANTPROPERTY_H
-#define QTVARIANTPROPERTY_H
+#pragma once
 
 #include "qtpropertybrowser.h"
 #include <QIcon>
@@ -332,5 +331,4 @@ QT_END_NAMESPACE
 #endif
 
 Q_DECLARE_METATYPE(QIcon)
-Q_DECLARE_METATYPE(QtIconMap)
-#endif
+Q_DECLARE_METATYPE(QtIconMap)
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/QtSignalChannel.h b/qt/widgets/common/inc/MantidQtWidgets/Common/QtSignalChannel.h
index 635e01f1f5ccb4ba69d38ffdd0308418694694a8..c6a61fbbaa4c81f7f22b49333e508586edbbef1a 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/QtSignalChannel.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/QtSignalChannel.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTAPI_QTSIGNALCHANNEL_H_
-#define MANTIDQTAPI_QTSIGNALCHANNEL_H_
+#pragma once
 
 #include "DllOption.h"
 
@@ -57,5 +56,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQTAPI_MANTIDWIDGET_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/RenameParDialog.h b/qt/widgets/common/inc/MantidQtWidgets/Common/RenameParDialog.h
index e060666ba388d376edb23fa041a23c5b83ab8618..4064a094a8c05661d67d1f8619dcd143b0791d6a 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/RenameParDialog.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/RenameParDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_RENAMEPARDIALOG_H_
-#define MANTIDQTMANTIDWIDGETS_RENAMEPARDIALOG_H_
+#pragma once
 
 #include "DllOption.h"
 #include "ui_RenameParDialog.h"
@@ -42,5 +41,3 @@ protected:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQTMANTIDWIDGETS_RENAMEPARDIALOG_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/RepoModel.h b/qt/widgets/common/inc/MantidQtWidgets/Common/RepoModel.h
index c5e7bcd894fc1050dafee0c3681395b0de172e89..0b7f8188bfcfdc63560c0cb1229139f4a3359e2a 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/RepoModel.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/RepoModel.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_API_REPOMODEL_H_
-#define MANTID_API_REPOMODEL_H_
+#pragma once
 #include "MantidAPI/ScriptRepository.h"
 #include "MantidQtWidgets/Common/DllOption.h"
 #include <QAbstractItemModel>
@@ -253,5 +252,3 @@ private slots:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif /* MANTID_API_SCRIPTREPOSITORYVIEW_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/RepoTreeView.h b/qt/widgets/common/inc/MantidQtWidgets/Common/RepoTreeView.h
index 9846f11aad63eca88f105fe37b5f28449ac5815a..3f9668f0c65ee5107f2ca26218d4c67637e7bad9 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/RepoTreeView.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/RepoTreeView.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_API_REPOTREEVIEW_H_
-#define MANTID_API_REPOTREEVIEW_H_
+#pragma once
 
 #include "DllOption.h"
 #include <QTreeView>
@@ -39,5 +38,3 @@ protected slots:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif /* MANTID_API_REPOTREEVIEW_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/SaveWorkspaces.h b/qt/widgets/common/inc/MantidQtWidgets/Common/SaveWorkspaces.h
index b743bcb3a1e446affaa7ff78a7a367f6d53fdd85..34a5546aaa2b0a584fcb48f1d5b67e3c0792ffa6 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/SaveWorkspaces.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/SaveWorkspaces.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_SAVEWORKSPACES_H_
-#define MANTIDQTMANTIDWIDGETS_SAVEWORKSPACES_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidQtWidgets/Common/MantidDialog.h"
@@ -87,5 +86,3 @@ private slots:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQTMANTIDWIDGETS_SAVEWORKSPACES_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/ScriptEditor.h b/qt/widgets/common/inc/MantidQtWidgets/Common/ScriptEditor.h
index 79fc79ca0b82f6f0aaf84df7c8a5c03ff003e5ad..5407509b1b4e692c8397f7e2c10649202ccbe1e7 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/ScriptEditor.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/ScriptEditor.h
@@ -5,8 +5,7 @@
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
 
-#ifndef SCRIPTEDITOR_H_
-#define SCRIPTEDITOR_H_
+#pragma once
 
 //----------------------------------
 // Includes
@@ -188,5 +187,3 @@ private:
   /// Name of group that the settings are stored under
   QString m_settingsGroup;
 };
-
-#endif // SCRIPTEDITOR_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/ScriptRepositoryView.h b/qt/widgets/common/inc/MantidQtWidgets/Common/ScriptRepositoryView.h
index 5dfa96413ea11dd52434b71709ac2a8d7f21868c..924051120ad8d3a3c628d52d41bb91c18ea60770 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/ScriptRepositoryView.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/ScriptRepositoryView.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_API_SCRIPTREPOSITORYVIEW_H_
-#define MANTID_API_SCRIPTREPOSITORYVIEW_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidQtWidgets/Common/MantidDialog.h"
@@ -88,5 +87,3 @@ private:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif /* MANTID_API_SCRIPTREPOSITORYVIEW_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/SelectFunctionDialog.h b/qt/widgets/common/inc/MantidQtWidgets/Common/SelectFunctionDialog.h
index 372ae7939d40afaa3c50400641917b804de69507..964e0090ab0311b494ae9bd8a190e79f1beab573 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/SelectFunctionDialog.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/SelectFunctionDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDWIDGETS_SELECTFUNCTIONDIALOG_H_
-#define MANTIDWIDGETS_SELECTFUNCTIONDIALOG_H_
+#pragma once
 
 //--------------------------------------------------
 // Includes
@@ -64,5 +63,3 @@ private slots:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDWIDGETS_SELECTFUNCTIONDIALOG_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/SelectWorkspacesDialog.h b/qt/widgets/common/inc/MantidQtWidgets/Common/SelectWorkspacesDialog.h
index 7e90b696dc805ef9534a0bbe405ba492d1dc3636..8fba396d142a2d399337adfeb64b4533fbd3bb9b 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/SelectWorkspacesDialog.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/SelectWorkspacesDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SELECTWORKSPACESDIALOG_H
-#define SELECTWORKSPACESDIALOG_H
+#pragma once
 
 //----------------------------
 //   Includes
@@ -60,5 +59,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* SELECTWORKSPACESDIALOG_H */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/SelectionNotificationService.h b/qt/widgets/common/inc/MantidQtWidgets/Common/SelectionNotificationService.h
index 43b2da7c367bd767125fd2ca1ca8af158f4c47f0..738b579dbd7d9980d4a752e7924fafb59dafb8fb 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/SelectionNotificationService.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/SelectionNotificationService.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTAPI_SELECTION_NOTIFICATION_SERVICE_H_
-#define MANTIDQTAPI_SELECTION_NOTIFICATION_SERVICE_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidKernel/SingletonHolder.h"
@@ -59,5 +58,3 @@ EXTERN_MANTIDQT_COMMON template class EXPORT_OPT_MANTIDQT_COMMON Mantid::
     Kernel::SingletonHolder<MantidQt::API::SelectionNotificationServiceImpl>;
 }
 } // namespace Mantid
-
-#endif // MANTIDQTAPI_SELECTION_NOTIFICATION_SERVICE_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/SequentialFitDialog.h b/qt/widgets/common/inc/MantidQtWidgets/Common/SequentialFitDialog.h
index e077c2ff349883d277e5acb66694a35fb3dab3db..60b75a2c9dcf38dc7ffb5470976c9478eefb1b38 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/SequentialFitDialog.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/SequentialFitDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SEQUENTIALFITDIALOG_H
-#define SEQUENTIALFITDIALOG_H
+#pragma once
 
 //----------------------------
 //   Includes
@@ -122,5 +121,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* SEQUENTIALFITDIALOG_H */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/SignalBlocker.h b/qt/widgets/common/inc/MantidQtWidgets/Common/SignalBlocker.h
index c308b25d6dbc9347c1924d06755ec5f9f25fa21a..b589a0d339af61faf3218b910ee0d6a682459a89 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/SignalBlocker.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/SignalBlocker.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_API_SIGNALBLOCKER_H_
-#define MANTID_API_SIGNALBLOCKER_H_
+#pragma once
 
 #include "DllOption.h"
 #include <QObject>
@@ -37,5 +36,3 @@ public:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif /* MANTID_API_SIGNALBLOCKER_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/SlicingAlgorithmDialog.h b/qt/widgets/common/inc/MantidQtWidgets/Common/SlicingAlgorithmDialog.h
index 1928528f18d95368053fa85a0ac5bcbc588a321a..a514674bdceaf94fde482cba9273c7956877b37a 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/SlicingAlgorithmDialog.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/SlicingAlgorithmDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTCUSTOMDIALOGS_SLICINGALGORITHMDIALOG_H_
-#define MANTIDQTCUSTOMDIALOGS_SLICINGALGORITHMDIALOG_H_
+#pragma once
 
 //----------------------
 // Includes
@@ -153,5 +152,3 @@ public:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/SlitCalculator.h b/qt/widgets/common/inc/MantidQtWidgets/Common/SlitCalculator.h
index 7f6d5243903ed2a3e0807dc6059e3101e747d65d..90b61d1356b9acb7badff44593a31fd9fcf6a229 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/SlitCalculator.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/SlitCalculator.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_SLITCALCULATOR_H
-#define MANTID_MANTIDWIDGETS_SLITCALCULATOR_H
+#pragma once
 
 //----------------------------------
 // Includes
@@ -47,5 +46,3 @@ private slots:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTID_MANTIDWIDGETS_SLITCALCULATOR_H */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/SyncedCheckboxes.h b/qt/widgets/common/inc/MantidQtWidgets/Common/SyncedCheckboxes.h
index 6c6e381275dabb3bc4d9911c1e559aa3c791edca..3afba732a28ad627fe8a64736aee1342d3494b78 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/SyncedCheckboxes.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/SyncedCheckboxes.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_SYNCEDCHECKBOXES_H_
-#define MANTIDQT_API_SYNCEDCHECKBOXES_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidKernel/System.h"
@@ -52,5 +51,3 @@ private:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif /* MANTIDQT_API_SYNCEDCHECKBOXES_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/TSVSerialiser.h b/qt/widgets/common/inc/MantidQtWidgets/Common/TSVSerialiser.h
index de00dd672bc1ff52ee2c9f2e137248a2f1b1fe2c..cc33813d820386ae51cb5ff8aed1b232763c7045 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/TSVSerialiser.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/TSVSerialiser.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_TSVSERIALISER_H_
-#define MANTID_TSVSERIALISER_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidKernel/CaseInsensitiveMap.h"
@@ -173,5 +172,3 @@ private:
 };
 } // namespace API
 } // namespace MantidQt
-
-#endif
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/Testing/QApplicationGlobalFixture.h b/qt/widgets/common/inc/MantidQtWidgets/Common/Testing/QApplicationGlobalFixture.h
index 6d6d5bc166e20a2249a689734d5246877214a0d1..3dd2009411facc6acd95ef65e10d8216f0b7fd78 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/Testing/QApplicationGlobalFixture.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/Testing/QApplicationGlobalFixture.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_WIDGETS_COMMON_QAPPLICATIONHOLDER_H
-#define MANTIDQT_WIDGETS_COMMON_QAPPLICATIONHOLDER_H
+#pragma once
 
 #include <cxxtest/GlobalFixture.h>
 
@@ -36,5 +35,3 @@ public:
   GNU_DIAG_ON("pedantic")
   QApplication *m_app;
 };
-
-#endif // MANTIDQT_WIDGETS_COMMON_QAPPLICATIONHOLDER_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/TextPropertyWidget.h b/qt/widgets/common/inc/MantidQtWidgets/Common/TextPropertyWidget.h
index 1ef7d31e66a29c557eb61970bf51595757a50d0f..50ffacf974b1e32c85b82d25edaff433181a3de2 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/TextPropertyWidget.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/TextPropertyWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_API_TEXTPROPERTYWIDGET_H_
-#define MANTID_API_TEXTPROPERTYWIDGET_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 #include "MantidQtWidgets/Common/PropertyWidget.h"
@@ -43,5 +42,3 @@ protected:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif /* MANTID_API_TEXTPROPERTYWIDGET_H_ */
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/TrackedAction.h b/qt/widgets/common/inc/MantidQtWidgets/Common/TrackedAction.h
index 10995997c9ce021b7133a93b540f2ee1404b127a..6e44482f6eea1fd9bf80fce68d4ad2f1960a7ac5 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/TrackedAction.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/TrackedAction.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_TRACKEDACTION_H_
-#define MANTID_MANTIDWIDGETS_TRACKEDACTION_H_
+#pragma once
 
 #include "DllOption.h"
 #include <QAction>
@@ -45,5 +44,3 @@ public slots:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTID_MANTIDWIDGETS_TRACKEDACTION_H_ */
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/UserFunctionDialog.h b/qt/widgets/common/inc/MantidQtWidgets/Common/UserFunctionDialog.h
index c4fa59808caeef180469eb940a57a00e5f23f880..426365224882f86d0c78c5ac9e9e005fa88a56fb 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/UserFunctionDialog.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/UserFunctionDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_USERFUNCTIONDIALOG_H_
-#define MANTIDQTMANTIDWIDGETS_USERFUNCTIONDIALOG_H_
+#pragma once
 
 #include "DllOption.h"
 #include "ui_UserFunctionDialog.h"
@@ -81,5 +80,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQTMANTIDWIDGETS_USERFUNCTIONDIALOG_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/UserInputValidator.h b/qt/widgets/common/inc/MantidQtWidgets/Common/UserInputValidator.h
index 577ea1f97c2173a2f54e0a7e84a001152654b9c8..d4bdddeb126b50122740ada84e0ca3ac3b71062a 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/UserInputValidator.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/UserInputValidator.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_CUSTOMINTERFACES_USERINPUTVALIDATOR_H_
-#define MANTID_CUSTOMINTERFACES_USERINPUTVALIDATOR_H_
+#pragma once
 
 #include "MantidAPI/MatrixWorkspace_fwd.h"
 #include "MantidQtWidgets/Common/DataSelector.h"
@@ -157,5 +156,3 @@ UserInputValidator::getADSWorkspace(std::string const &workspaceName) {
 
 } // namespace CustomInterfaces
 } // namespace MantidQt
-
-#endif // MANTID_CUSTOMINTERFACES_USERINPUTVALIDATOR_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/UserSubWindow.h b/qt/widgets/common/inc/MantidQtWidgets/Common/UserSubWindow.h
index 864b71ac824f2104a1b5585970000bee6de5c6e2..0abe307ff0eb0eebbffccda8e42587cab68f587b 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/UserSubWindow.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/UserSubWindow.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_USERSUBWINDOW_H_
-#define MANTIDQT_API_USERSUBWINDOW_H_
+#pragma once
 
 /* Used to register classes into the factory. Creates a global object in an
  * anonymous namespace. The object itself does nothing, but the comma operator
@@ -151,5 +150,3 @@ private:
 };
 } // namespace API
 } // namespace MantidQt
-
-#endif // MANTIDQT_API_USERSUBWINDOW_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/UserSubWindowFactory.h b/qt/widgets/common/inc/MantidQtWidgets/Common/UserSubWindowFactory.h
index 311e471a50f8f34ed384e9a11831c7b7febb4f66..ec7ba336de0c77b6cdfc62052234f13e8ca8c0a7 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/UserSubWindowFactory.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/UserSubWindowFactory.h
@@ -5,8 +5,7 @@
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
 
-#ifndef MANTIDQT_API_USERSUBWINDOWFACTORYIMPL_H_
-#define MANTIDQT_API_USERSUBWINDOWFACTORYIMPL_H_
+#pragma once
 
 //------------------------
 // Includes
@@ -160,5 +159,3 @@ EXTERN_MANTIDQT_COMMON template class EXPORT_OPT_MANTIDQT_COMMON
     Mantid::Kernel::SingletonHolder<MantidQt::API::UserSubWindowFactoryImpl>;
 } // namespace Kernel
 } // namespace Mantid
-
-#endif
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/VatesViewerInterface.h b/qt/widgets/common/inc/MantidQtWidgets/Common/VatesViewerInterface.h
index dac78663ff02555146d8d7718b46508aaafd0f84..10ff3744c8274cb17c85364201fac079fe34b62b 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/VatesViewerInterface.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/VatesViewerInterface.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_VATESVIEWERINTERFACE_H_
-#define MANTIDQT_API_VATESVIEWERINTERFACE_H_
+#pragma once
 
 #include "DllOption.h"
 #include "IProjectSerialisable.h"
@@ -75,5 +74,3 @@ public slots:
 };
 } // namespace API
 } // namespace MantidQt
-
-#endif // MANTIDQT_API_VATESVIEWERINTERFACE_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/WidgetDllOption.h b/qt/widgets/common/inc/MantidQtWidgets/Common/WidgetDllOption.h
index dd6d27019c4ba5950ec9fc0f24bb3d45268960d4..9fa90c30b14eaa5a1d20837f6b81ecd61025dfcf 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/WidgetDllOption.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/WidgetDllOption.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGETS_DLLOPTION_H_
-#define MANTIDQT_MANTIDWIDGETS_DLLOPTION_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 
@@ -14,5 +13,3 @@
 #else
 #define EXPORT_OPT_MANTIDQT_MANTIDWIDGETS DLLImport
 #endif /* IN_MANTIDQT_MANTIDWIDGETS */
-
-#endif // MANTIDQT_MANTIDWIDGETS_DLLOPTION_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/WidgetScrollbarDecorator.h b/qt/widgets/common/inc/MantidQtWidgets/Common/WidgetScrollbarDecorator.h
index bbc34a44962b6c26619d63655b2747510f94097e..47a5ecd08eace83ee7b749155e168ea3f4c1c8f7 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/WidgetScrollbarDecorator.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/WidgetScrollbarDecorator.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_WIDGETSCROLLBARDECORATOR_H_
-#define MANTIDQT_API_WIDGETSCROLLBARDECORATOR_H_
+#pragma once
 
 //----------------------------------
 // Includes
@@ -110,5 +109,3 @@ private:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif // MANTIDQT_API_WIDGETSCROLLBARDECORATOR_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/WindowIcons.h b/qt/widgets/common/inc/MantidQtWidgets/Common/WindowIcons.h
index 179bf6e3ea79d2e5ebdaac41b561fab80b82b2e6..5b2e92d506b29c468f1d4c053cce76b314313a5f 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/WindowIcons.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/WindowIcons.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_WINDOWICONS_H_
-#define MANTIDQT_API_WINDOWICONS_H_
+#pragma once
 
 #include "DllOption.h"
 #include <QIcon>
@@ -36,5 +35,4 @@ private:
   QMap<std::string, std::string> m_idToPixmapName;
 };
 } // namespace API
-} // namespace MantidQt
-#endif // MANTIDQT_API_WINDOWICONS_H_
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspaceIcons.h b/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspaceIcons.h
index ed2dfcce9a68602b65ba866607f568a75a618dae..c5c0f64c2315f330914554dab9263f2dee0d0f21 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspaceIcons.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspaceIcons.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_WORKSPACEICONS_H_
-#define MANTIDQT_API_WORKSPACEICONS_H_
+#pragma once
 
 #include "DllOption.h"
 #include <QMap>
@@ -34,5 +33,4 @@ private:
   QMap<std::string, std::string> m_idToPixmapName;
 };
 } // namespace API
-} // namespace MantidQt
-#endif // MANTIDQT_API_WORKSPACEICONS_H_
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspaceObserver.h b/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspaceObserver.h
index e762d5e6d238bf3daf0d67986e1cd6892b4c1968..d21ec9212e85dc5b544caa7c2cbc62b996b2b3c7 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspaceObserver.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspaceObserver.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef WORKSPACE_OBSERVER_H
-#define WORKSPACE_OBSERVER_H
+#pragma once
 
 #include "DllOption.h"
 #include "MantidAPI/AnalysisDataService.h"
@@ -245,5 +244,3 @@ private:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/ADSAdapter.h b/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/ADSAdapter.h
index 760f131febc134a2f201d4066c758a05d03b4c7c..e5c7a7552ad1fbae7013c151bc847aa6878603f2 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/ADSAdapter.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/ADSAdapter.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_ADSADAPTER_H_
-#define MANTID_MANTIDWIDGETS_ADSADAPTER_H_
+#pragma once
 
 #include "MantidQtWidgets/Common/DllOption.h"
 #include "MantidQtWidgets/Common/WorkspaceObserver.h"
@@ -81,5 +80,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTID_MANTIDWIDGETS_ADSADAPTER_H_
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/IWorkspaceDockView.h b/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/IWorkspaceDockView.h
index abe90d75626e6297d7a3b4d5325765f9f968bdc9..6ec190e4815ea7809b6276c50cbbc96c34dbab53 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/IWorkspaceDockView.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/IWorkspaceDockView.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGETS_IWORKSPACEDOCKVIEW_H_
-#define MANTIDQT_MANTIDWIDGETS_IWORKSPACEDOCKVIEW_H_
+#pragma once
 
 #include "MantidAPI/IAlgorithm_fwd.h"
 #include "MantidAPI/Workspace_fwd.h"
@@ -93,5 +92,3 @@ public:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQT_MANTIDWIDGETS_IWORKSPACEDOCKVIEW_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/ViewNotifiable.h b/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/ViewNotifiable.h
index d08cddf458a564874f3e9cae329de5e05db6319f..af0e72ce88fa7dacf2cb68ef87347c04b7d302c6 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/ViewNotifiable.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/ViewNotifiable.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_VIEWNOTIFIABLE_H_
-#define MANTID_MANTIDWIDGETS_VIEWNOTIFIABLE_H_
+#pragma once
 /**
 \class  ViewNotifiable
 \brief  Mixin class allows view notifications
@@ -60,5 +59,4 @@ public:
 };
 
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTID_MANTIDWIDGETS_VIEWNOTIFIABLE_H_
\ No newline at end of file
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/WorkspaceDockMockObjects.h b/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/WorkspaceDockMockObjects.h
index c512e1908afa7650d6d7a9511bed6de5f90dbe8a..01586892eb0f1d96f535d25361455a6c375917a3 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/WorkspaceDockMockObjects.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/WorkspaceDockMockObjects.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGETS_WORKSPACEDOCKMOCKOBJECTS_H
-#define MANTIDQT_MANTIDWIDGETS_WORKSPACEDOCKMOCKOBJECTS_H
+#pragma once
 
 #include "MantidKernel/WarningSuppressions.h"
 
@@ -111,5 +110,3 @@ public:
 };
 
 GNU_DIAG_ON_SUGGEST_OVERRIDE
-
-#endif // MANTIDQT_MANTIDWIDGETS_WORKSPACEDOCKMOCKOBJECTS_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/WorkspacePresenter.h b/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/WorkspacePresenter.h
index d59b6cb1c587c3b9f7936df11087f451533de2ba..7f62b4a5feb8793e28c7591fecfd06f5fc8a7491 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/WorkspacePresenter.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/WorkspacePresenter.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGETS_WORKSPACEPRESENTER_H_
-#define MANTIDQT_MANTIDWIDGETS_WORKSPACEPRESENTER_H_
+#pragma once
 
 #include "MantidQtWidgets/Common/DllOption.h"
 #include "MantidQtWidgets/Common/WorkspacePresenter/ViewNotifiable.h"
@@ -92,5 +91,4 @@ private:
   ADSAdapter_uptr m_adapter;
 };
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQT_MANTIDWIDGETS_WORKSPACEPRESENTER_H_
\ No newline at end of file
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/WorkspaceProvider.h b/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/WorkspaceProvider.h
index 5c4d68e80ffaf15523305bfbd6215a78d6979196..f4203c637d4146d6efec0066ac51c919d382c1ee 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/WorkspaceProvider.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/WorkspaceProvider.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_WORKSPACEPROVIDER_H_
-#define MANTID_MANTIDWIDGETS_WORKSPACEPROVIDER_H_
+#pragma once
 
 #include "MantidAPI/Workspace_fwd.h"
 #include <boost/shared_ptr.hpp>
@@ -39,5 +38,4 @@ public:
 };
 
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTID_MANTIDWIDGETS_WORKSPACEPROVIDER_H_
\ No newline at end of file
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/WorkspaceProviderNotifiable.h b/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/WorkspaceProviderNotifiable.h
index af967e8ba2ad2df02959a2cbe38ef4ce216535e9..e53e80c6d06e30b27c9555b24595043d2afae395 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/WorkspaceProviderNotifiable.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/WorkspaceProviderNotifiable.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_WORKSPACEPROVIDERNOTIFIABLE_H_
-#define MANTID_MANTIDWIDGETS_WORKSPACEPROVIDERNOTIFIABLE_H_
+#pragma once
 
 /**
 \class  WorkspaceProviderNotifiable
@@ -36,5 +35,4 @@ public:
 };
 
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTID_MANTIDWIDGETS_ADSNOTIFIABLE_H_
\ No newline at end of file
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/WorkspaceTreeWidget.h b/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/WorkspaceTreeWidget.h
index 68a0672511e9f155a3003ae64ea47a49aaa8713e..2ca6dd0d1ad55aa866b469b85d65792d3a8b28f3 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/WorkspaceTreeWidget.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/WorkspaceTreeWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGETS_WORKSPACETREEWIDGET_H
-#define MANTIDQT_MANTIDWIDGETS_WORKSPACETREEWIDGET_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DllOption.h"
 #include "MantidQtWidgets/Common/MantidTreeWidget.h"
@@ -277,5 +276,4 @@ signals:
   void signalUpdateTree(const TopLevelItems & /*_t1*/);
 };
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQT_MANTIDWIDGETS_WORKSPACETREEWIDGET_H
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/WorkspaceTreeWidgetSimple.h b/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/WorkspaceTreeWidgetSimple.h
index 5405833a05a6c5d6f2c12bb92b384ea2a9b221d4..0b8320f2001165d3f2ceca35e66788256ea9e048 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/WorkspaceTreeWidgetSimple.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspacePresenter/WorkspaceTreeWidgetSimple.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGETS_WORKSPACETREEWIDGETSIMPLE_H
-#define MANTIDQT_MANTIDWIDGETS_WORKSPACETREEWIDGETSIMPLE_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DllOption.h"
 #include "MantidQtWidgets/Common/WorkspacePresenter/WorkspaceTreeWidget.h"
@@ -79,5 +78,4 @@ private:
       *m_showAlgorithmHistory, *m_showDetectors;
 };
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // MANTIDQT_MANTIDWIDGETS_WORKSPACETREEWIDGETSIMPLE_H
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspaceSelector.h b/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspaceSelector.h
index dc4be7fce201ae0ccf04ca8b04986b9dd0ea45dd..e53b14f9aaddf7916a7cf5b9a5c6488b2069b989 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspaceSelector.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/WorkspaceSelector.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_WORKSPACESELECTOR_H_
-#define MANTIDQTMANTIDWIDGETS_WORKSPACESELECTOR_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidAPI/AnalysisDataService.h"
@@ -141,5 +140,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQTMANTIDWIDGETS_INSTRUMENTSELECTOR_H_
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/pixmaps.h b/qt/widgets/common/inc/MantidQtWidgets/Common/pixmaps.h
index c6b4e7166ab0d926bed920a2bc4fc20c77d47765..04f7117147a9908ddf57b0dc901a8f13599778b1 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/pixmaps.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/pixmaps.h
@@ -28,8 +28,7 @@
  *                                                                         *
  ***************************************************************************/
 
-#ifndef MANTIDQT_API_PIXMAPS_H
-#define MANTIDQT_API_PIXMAPS_H
+#pragma once
 
 #include "MantidQtWidgets/Common/DllOption.h"
 #include "qpixmap.h"
@@ -40,5 +39,3 @@ namespace API {
 EXPORT_OPT_MANTIDQT_COMMON QPixmap getQPixmap(const std::string &name);
 } // namespace API
 } // namespace MantidQt
-
-#endif // MANTIDQT_API_PIXMAPS_H
diff --git a/qt/widgets/common/inc/MantidQtWidgets/Common/pqHelpWindow.h b/qt/widgets/common/inc/MantidQtWidgets/Common/pqHelpWindow.h
index 0e48246248bb87258b4a23962c5fe2a6be2bf9f7..3ad5450c2912319e3cb31eb75fd62907d3bb1c83 100644
--- a/qt/widgets/common/inc/MantidQtWidgets/Common/pqHelpWindow.h
+++ b/qt/widgets/common/inc/MantidQtWidgets/Common/pqHelpWindow.h
@@ -29,8 +29,7 @@ NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 ========================================================================*/
-#ifndef __pqHelpWindow_h
-#define __pqHelpWindow_h
+#pragma once
 
 #include "DllOption.h"
 #include <QMainWindow>
@@ -123,5 +122,3 @@ private:
   class pqNetworkAccessManager;
   friend class pqNetworkAccessManager;
 };
-
-#endif
diff --git a/qt/widgets/common/test/AlgorithmHintStrategyTest.h b/qt/widgets/common/test/AlgorithmHintStrategyTest.h
index 5a9e19b0bdcf70953804e3b9b43842ee04f781c6..c65c2b1e52a209d6310fb6cc93d14fedb6e0eb94 100644
--- a/qt/widgets/common/test/AlgorithmHintStrategyTest.h
+++ b/qt/widgets/common/test/AlgorithmHintStrategyTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_ALGORITHMHINTSTRATEGYTEST_H
-#define MANTID_MANTIDWIDGETS_ALGORITHMHINTSTRATEGYTEST_H
+#pragma once
 
 #include "MantidAPI/AlgorithmManager.h"
 #include "MantidAPI/FrameworkManager.h"
@@ -103,5 +102,3 @@ public:
 protected:
   IAlgorithm_sptr m_propAlg;
 };
-
-#endif /*MANTID_MANTIDWIDGETS_ALGORITHMHINTSTRATEGYTEST_H */
diff --git a/qt/widgets/common/test/AlgorithmProgress/AlgorithmProgressDialogPresenterTest.h b/qt/widgets/common/test/AlgorithmProgress/AlgorithmProgressDialogPresenterTest.h
index cde88c6662cf5466882646ae311b2c1ffff98512..1ab8a1cc360595f93ed7630519920d697f6a69f7 100644
--- a/qt/widgets/common/test/AlgorithmProgress/AlgorithmProgressDialogPresenterTest.h
+++ b/qt/widgets/common/test/AlgorithmProgress/AlgorithmProgressDialogPresenterTest.h
@@ -1,5 +1,4 @@
-#ifndef MANTIDQT_MANTIDWIDGETS_ALGORITHMPROGRESSPRESENTERTEST_H_
-#define MANTIDQT_MANTIDWIDGETS_ALGORITHMPROGRESSPRESENTERTEST_H_
+#pragma once
 
 #include "MantidAPI/AlgorithmFactory.h"
 #include "MantidAPI/AlgorithmManager.h"
@@ -165,5 +164,4 @@ public:
 
 private:
   std::unique_ptr<NiceMock<MockAlgorithmProgressDialogWidget>> mockDialogView;
-};
-#endif // MANTIDQT_MANTIDWIDGETS_ALGORITHMPROGRESSTEST_H_
+};
\ No newline at end of file
diff --git a/qt/widgets/common/test/AlgorithmProgress/AlgorithmProgressPresenterTest.h b/qt/widgets/common/test/AlgorithmProgress/AlgorithmProgressPresenterTest.h
index ada369676b4b2028704fab6fa84e68a7bab300cb..b629b7de198aa69474b9c16d0580a97d90ac4e99 100644
--- a/qt/widgets/common/test/AlgorithmProgress/AlgorithmProgressPresenterTest.h
+++ b/qt/widgets/common/test/AlgorithmProgress/AlgorithmProgressPresenterTest.h
@@ -1,5 +1,4 @@
-#ifndef MANTIDQT_MANTIDWIDGETS_ALGORITHMPROGRESSTEST_H_
-#define MANTIDQT_MANTIDWIDGETS_ALGORITHMPROGRESSTEST_H_
+#pragma once
 
 #include "MantidAPI/AlgorithmFactory.h"
 #include "MantidAPI/AlgorithmManager.h"
@@ -147,5 +146,4 @@ public:
 
 private:
   std::unique_ptr<NiceMock<MockAlgorithmProgressWidget>> mockView;
-};
-#endif // MANTIDQT_MANTIDWIDGETS_ALGORITHMPROGRESSTEST_H_
+};
\ No newline at end of file
diff --git a/qt/widgets/common/test/AlgorithmProgress/ManualProgressReporter.h b/qt/widgets/common/test/AlgorithmProgress/ManualProgressReporter.h
index 0fc6d571d835756c226a146b8616f5efbe43f5a9..eb6676fd5b57cd0ab43c451353c6a399a1599eec 100644
--- a/qt/widgets/common/test/AlgorithmProgress/ManualProgressReporter.h
+++ b/qt/widgets/common/test/AlgorithmProgress/ManualProgressReporter.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGETS_MANUALPROGRESSREPORTER_H_
-#define MANTIDQT_MANTIDWIDGETS_MANUALPROGRESSREPORTER_H_
+#pragma once
 
 #include "MantidAPI/Algorithm.h"
 #include "MantidKernel/System.h"
@@ -61,5 +60,3 @@ private:
 
 } // namespace Algorithms
 } // namespace Mantid
-
-#endif /* MANTIDQT_MANTIDWIDGETS_MANUALPROGRESSREPORTER_H_ */
\ No newline at end of file
diff --git a/qt/widgets/common/test/AlgorithmProgress/MockAlgorithmProgressDialogWidget.h b/qt/widgets/common/test/AlgorithmProgress/MockAlgorithmProgressDialogWidget.h
index 7cdf4770dd2ca2075c121d2696a5e9f66e9d1b66..70b463889f173d16a684e0d45a7f7ba9c995ec88 100644
--- a/qt/widgets/common/test/AlgorithmProgress/MockAlgorithmProgressDialogWidget.h
+++ b/qt/widgets/common/test/AlgorithmProgress/MockAlgorithmProgressDialogWidget.h
@@ -1,5 +1,4 @@
-#ifndef MANTID_MANTIDWIDGETS_MOCKALGORITHMPROGRESSDIALOGWIDGET_H
-#define MANTID_MANTIDWIDGETS_MOCKALGORITHMPROGRESSDIALOGWIDGET_H
+#pragma once
 
 #include "MantidKernel/WarningSuppressions.h"
 #include "MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressDialogPresenter.h"
@@ -35,5 +34,4 @@ public:
   // This is the mocked main progress bar,
   // always shown on the Workbench GUI
   std::shared_ptr<MockAlgorithmProgressWidget> mainProgressBar;
-};
-#endif // MANTID_MANTIDWIDGETS_MOCKALGORITHMPROGRESSWIDGET_H
+};
\ No newline at end of file
diff --git a/qt/widgets/common/test/AlgorithmProgress/MockAlgorithmProgressWidget.h b/qt/widgets/common/test/AlgorithmProgress/MockAlgorithmProgressWidget.h
index d7fb57f5b582d0cf58f880f71c3796c06fab2f90..2f74178f29c9a700ec2f05c534c27570787ea29c 100644
--- a/qt/widgets/common/test/AlgorithmProgress/MockAlgorithmProgressWidget.h
+++ b/qt/widgets/common/test/AlgorithmProgress/MockAlgorithmProgressWidget.h
@@ -1,5 +1,4 @@
-#ifndef MANTID_MANTIDWIDGETS_MOCKALGORITHMPROGRESSWIDGET_H
-#define MANTID_MANTIDWIDGETS_MOCKALGORITHMPROGRESSWIDGET_H
+#pragma once
 
 #include "MantidKernel/WarningSuppressions.h"
 #include "MantidQtWidgets/Common/AlgorithmProgress/AlgorithmProgressPresenter.h"
@@ -30,5 +29,4 @@ public:
   MOCK_METHOD0(showDetailsDialog, void());
 
   std::shared_ptr<AlgorithmProgressPresenter> m_presenter;
-};
-#endif // MANTID_MANTIDWIDGETS_MOCKALGORITHMPROGRESSWIDGET_H
+};
\ No newline at end of file
diff --git a/qt/widgets/common/test/Batch/BuildSubtreeItemsTest.h b/qt/widgets/common/test/Batch/BuildSubtreeItemsTest.h
index 6dd7fecffca803dfc9481cdfbe4f92921d34dfaf..f2edf8c953ca5511ca109a35bc9380fe045fe69a 100644
--- a/qt/widgets/common/test/Batch/BuildSubtreeItemsTest.h
+++ b/qt/widgets/common/test/Batch/BuildSubtreeItemsTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_BUILDSUBTREETEST_H
-#define MANTID_MANTIDWIDGETS_BUILDSUBTREETEST_H
+#pragma once
 
 #include "MantidQtWidgets/Common/Batch/BuildSubtreeItems.h"
 #include "MantidQtWidgets/Common/Batch/QtStandardItemTreeAdapter.h"
@@ -160,5 +159,4 @@ public:
       TS_ASSERT_EQUALS(childOfChildItem->rowCount(), 0);
     }
   }
-};
-#endif
+};
\ No newline at end of file
diff --git a/qt/widgets/common/test/Batch/ExtractSubtreesTest.h b/qt/widgets/common/test/Batch/ExtractSubtreesTest.h
index 016c7342ca715a42e3dc30df97a4e05de75855f0..34212087afdd30269a4f9dffa48e23dab0b25bcc 100644
--- a/qt/widgets/common/test/Batch/ExtractSubtreesTest.h
+++ b/qt/widgets/common/test/Batch/ExtractSubtreesTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_EXTRACTSUBTREESTEST_H
-#define MANTID_MANTIDWIDGETS_EXTRACTSUBTREESTEST_H
+#pragma once
 
 #include "MantidQtWidgets/Common/Batch/ExtractSubtrees.h"
 #include "MantidQtWidgets/Common/Batch/Row.h"
@@ -281,5 +280,4 @@ public:
     auto roots = extractSubtrees(region);
     TS_ASSERT(!roots.is_initialized())
   }
-};
-#endif
+};
\ No newline at end of file
diff --git a/qt/widgets/common/test/Batch/FindSubtreeRootsTest.h b/qt/widgets/common/test/Batch/FindSubtreeRootsTest.h
index 2b9025cf57114faa649a42a111e3575851514d51..33359338db32fbd0cf44f63e4d40af9fa0073494 100644
--- a/qt/widgets/common/test/Batch/FindSubtreeRootsTest.h
+++ b/qt/widgets/common/test/Batch/FindSubtreeRootsTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_FINDSUBTREEROOTS_H
-#define MANTID_MANTIDWIDGETS_FINDSUBTREEROOTS_H
+#pragma once
 
 #include "MantidQtWidgets/Common/Batch/FindSubtreeRoots.h"
 #include "MantidQtWidgets/Common/Batch/RowLocation.h"
@@ -242,5 +241,3 @@ public:
     TS_ASSERT(!roots.is_initialized())
   }
 };
-
-#endif // MANTID_MANTIDWIDGETS_FINDSUBTREEROOTS_H
diff --git a/qt/widgets/common/test/Batch/QtAdaptedModelTest.h b/qt/widgets/common/test/Batch/QtAdaptedModelTest.h
index b4d105d8b0117c653e13c5dff4d03945571d544b..867cee63bfdd9063a5d0d7b9574e58fc2e34d5fd 100644
--- a/qt/widgets/common/test/Batch/QtAdaptedModelTest.h
+++ b/qt/widgets/common/test/Batch/QtAdaptedModelTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_QTADAPTEDMODELTEST_H
-#define MANTID_MANTIDWIDGETS_QTADAPTEDMODELTEST_H
+#pragma once
 
 #include "MantidQtWidgets/Common/Batch/QtStandardItemTreeAdapter.h"
 #include <QModelIndex>
@@ -114,5 +113,3 @@ public:
                      QString::fromStdString(cells[1].contentText()));
   }
 };
-
-#endif // MANTID_MANTIDWIDGETS_QTADAPTEDMODELTEST_H
diff --git a/qt/widgets/common/test/Batch/RowLocationTest.h b/qt/widgets/common/test/Batch/RowLocationTest.h
index 804737bb9242e86834a898e150a1f04493731209..5832aab5c4e446f11eeb82162d1f03fc57d5ddf3 100644
--- a/qt/widgets/common/test/Batch/RowLocationTest.h
+++ b/qt/widgets/common/test/Batch/RowLocationTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_ROWLOCATIONTEST_H
-#define MANTID_MANTIDWIDGETS_ROWLOCATIONTEST_H
+#pragma once
 
 #include "MantidQtWidgets/Common/Batch/RowLocation.h"
 #include <algorithm>
@@ -156,5 +155,3 @@ public:
         !pathsSameUntilDepth(1, RowLocation({1, 1}), RowLocation({2, 2})));
   }
 };
-
-#endif // MANTID_MANTIDWIDGETS_ROWLOCATIONTEST_H
diff --git a/qt/widgets/common/test/BatchAlgorithmRunnerTest.h b/qt/widgets/common/test/BatchAlgorithmRunnerTest.h
index b64b705fe51785d96df46fa6ac06f0a86be56f83..d588844896b0c4c758cf59944bfcd9a40c751781 100644
--- a/qt/widgets/common/test/BatchAlgorithmRunnerTest.h
+++ b/qt/widgets/common/test/BatchAlgorithmRunnerTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_BATCHALGORITHMRUNNERTEST_H_
-#define MANTIDQT_API_BATCHALGORITHMRUNNERTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -177,5 +176,3 @@ private:
   BatchAlgorithmRunner::AlgorithmRuntimeProps inputFromCropProps;
   BatchAlgorithmRunner::AlgorithmRuntimeProps inputFromScaleProps;
 };
-
-#endif /* MANTIDQT_API_BATCHALGORITHMRUNNERTEST_H_ */
diff --git a/qt/widgets/common/test/ConvolutionFunctionModelTest.h b/qt/widgets/common/test/ConvolutionFunctionModelTest.h
index cf0b3759b1be1a93bc998d9bafc206efe2868384..3174d1359e77198ed650e47fd6d658c496f91056 100644
--- a/qt/widgets/common/test/ConvolutionFunctionModelTest.h
+++ b/qt/widgets/common/test/ConvolutionFunctionModelTest.h
@@ -5,8 +5,7 @@
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
 
-#ifndef MANTIDWIDGETS_CONVOLUTIONFUNCTIONMODELTEST_H_
-#define MANTIDWIDGETS_CONVOLUTIONFUNCTIONMODELTEST_H_
+#pragma once
 
 #include "MantidAPI/FrameworkManager.h"
 #include "MantidAPI/FunctionFactory.h"
@@ -552,5 +551,3 @@ public:
                      "f1.f1.f0.");
   }
 };
-
-#endif // MANTIDWIDGETS_CONVOLUTIONFUNCTIONMODELTEST_H_
diff --git a/qt/widgets/common/test/DataProcessorUI/CommandsTest.h b/qt/widgets/common/test/DataProcessorUI/CommandsTest.h
index 0b16824d1b424b11b296b00bb2bcf19af0be3520..e1c2633d0f5a4abb7d98461be0b144ba16bfff8b 100644
--- a/qt/widgets/common/test/DataProcessorUI/CommandsTest.h
+++ b/qt/widgets/common/test/DataProcessorUI/CommandsTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_DATAPROCESSORCOMMANDSTEST_H
-#define MANTID_MANTIDWIDGETS_DATAPROCESSORCOMMANDSTEST_H
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 #include <gmock/gmock.h>
@@ -385,5 +384,4 @@ public:
     // Verify expectations
     TS_ASSERT(Mock::VerifyAndClearExpectations(&mockPresenter));
   }
-};
-#endif /* MANTID_MANTIDWIDGETS_DATAPROCESSORCOMMANDSTEST_H */
+};
\ No newline at end of file
diff --git a/qt/widgets/common/test/DataProcessorUI/GenerateNotebookTest.h b/qt/widgets/common/test/DataProcessorUI/GenerateNotebookTest.h
index 1e2fcb495c28790e7cc5166d7f523f04a82032fa..db7f6452290b18a94c4ec23b33cc851e02b7e00c 100644
--- a/qt/widgets/common/test/DataProcessorUI/GenerateNotebookTest.h
+++ b/qt/widgets/common/test/DataProcessorUI/GenerateNotebookTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_DATAPROCESSORGENERATENOTEBOOKTEST_H
-#define MANTID_MANTIDWIDGETS_DATAPROCESSORGENERATENOTEBOOKTEST_H
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 #include <gmock/gmock.h>
@@ -911,5 +910,3 @@ public:
     TS_ASSERT_EQUALS(notebookLines[93].toStdString(), groupWorkspacesString);
   }
 };
-
-#endif // MANTID_MANTIDWIDGETS_DATAPROCESSORGENERATENOTEBOOKTEST_H
diff --git a/qt/widgets/common/test/DataProcessorUI/GenericDataProcessorPresenterTest.h b/qt/widgets/common/test/DataProcessorUI/GenericDataProcessorPresenterTest.h
index 492e633956910758e9998c6efb584242e4677794..074d53972994340a907fa24a6780d0601cc5ca72 100644
--- a/qt/widgets/common/test/DataProcessorUI/GenericDataProcessorPresenterTest.h
+++ b/qt/widgets/common/test/DataProcessorUI/GenericDataProcessorPresenterTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_GENERICDATAPROCESSORPRESENTERTEST_H
-#define MANTID_MANTIDWIDGETS_GENERICDATAPROCESSORPRESENTERTEST_H
+#pragma once
 #include <cxxtest/TestSuite.h>
 #include <gmock/gmock.h>
 #include <gtest/gtest.h>
@@ -3360,5 +3359,4 @@ public:
 
     TS_ASSERT(Mock::VerifyAndClearExpectations(&mockDataProcessorView));
   }
-};
-#endif /* MANTID_MANTIDWIDGETS_GENERICDATAPROCESSORPRESENTERTEST_H */
+};
\ No newline at end of file
diff --git a/qt/widgets/common/test/DataProcessorUI/OneLevelTreeManagerTest.h b/qt/widgets/common/test/DataProcessorUI/OneLevelTreeManagerTest.h
index b2f557c5131b43dba6b9aeedc5367cc76814dc86..289a242cbfdfaffae2eaffda022c581e0aa0d760 100644
--- a/qt/widgets/common/test/DataProcessorUI/OneLevelTreeManagerTest.h
+++ b/qt/widgets/common/test/DataProcessorUI/OneLevelTreeManagerTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_DATAPROCESSORONELEVELTREEMANAGERTEST_H
-#define MANTID_MANTIDWIDGETS_DATAPROCESSORONELEVELTREEMANAGERTEST_H
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 #include <gmock/gmock.h>
@@ -373,5 +372,4 @@ public:
     TS_ASSERT_EQUALS(data[2][2]->data(), newRow);
     TS_ASSERT_EQUALS(data[3][3]->data(), newRow);
   }
-};
-#endif /* MANTID_MANTIDWIDGETS_DATAPROCESSORONELEVELTREEMANAGERTEST_H */
+};
\ No newline at end of file
diff --git a/qt/widgets/common/test/DataProcessorUI/PostprocessingAlgorithmTest.h b/qt/widgets/common/test/DataProcessorUI/PostprocessingAlgorithmTest.h
index a2a59e97595d6847e24f283b42f8d2b26029b68f..b028b36061f29f60ab13f823109635bcf9ac803d 100644
--- a/qt/widgets/common/test/DataProcessorUI/PostprocessingAlgorithmTest.h
+++ b/qt/widgets/common/test/DataProcessorUI/PostprocessingAlgorithmTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_DATAPROCESSORPOSTPROCESSINGALGORITHMTEST_H
-#define MANTID_MANTIDWIDGETS_DATAPROCESSORPOSTPROCESSINGALGORITHMTEST_H
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 #include <gmock/gmock.h>
@@ -66,5 +65,4 @@ public:
   }
 
   // Add more algorithms you want to test here
-};
-#endif /* MANTID_MANTIDWIDGETS_DATAPROCESSORPOSTPROCESSINGALGORITHMTEST_H */
+};
\ No newline at end of file
diff --git a/qt/widgets/common/test/DataProcessorUI/PreprocessMapTest.h b/qt/widgets/common/test/DataProcessorUI/PreprocessMapTest.h
index 8a4f4c88bb955649cf9b05955c0eebc02cfae0f4..84f431d1c98f91e5eb2f641e96a1d328e14482ff 100644
--- a/qt/widgets/common/test/DataProcessorUI/PreprocessMapTest.h
+++ b/qt/widgets/common/test/DataProcessorUI/PreprocessMapTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_DATAPROCESSORPREPROCESSMAPTEST_H
-#define MANTID_MANTIDWIDGETS_DATAPROCESSORPREPROCESSMAPTEST_H
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 #include <gmock/gmock.h>
@@ -56,5 +55,4 @@ public:
                                    "SecondTransmissionRun"};
     TS_ASSERT_EQUALS(algTrans.blacklist(), blacklist);
   }
-};
-#endif /* MANTID_MANTIDWIDGETS_DATAPROCESSORPREPROCESSMAPTEST_H */
+};
\ No newline at end of file
diff --git a/qt/widgets/common/test/DataProcessorUI/PreprocessingAlgorithmTest.h b/qt/widgets/common/test/DataProcessorUI/PreprocessingAlgorithmTest.h
index 2191516d672be54ac2d59117369f533db0547f53..26cd86f34d550d4daec707accd71e48e183f6641 100644
--- a/qt/widgets/common/test/DataProcessorUI/PreprocessingAlgorithmTest.h
+++ b/qt/widgets/common/test/DataProcessorUI/PreprocessingAlgorithmTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_DATAPROCESSORPREPROCESSINGALGORITHMTEST_H
-#define MANTID_MANTIDWIDGETS_DATAPROCESSORPREPROCESSINGALGORITHMTEST_H
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 #include <gmock/gmock.h>
@@ -85,5 +84,4 @@ public:
   }
 
   // Add specific algorithms you want to test here
-};
-#endif /* MANTID_MANTIDWIDGETS_DATAPROCESSORPREPROCESSINGALGORITHMTEST_H */
+};
\ No newline at end of file
diff --git a/qt/widgets/common/test/DataProcessorUI/ProcessingAlgorithmBaseTest.h b/qt/widgets/common/test/DataProcessorUI/ProcessingAlgorithmBaseTest.h
index 7426dec7aa7a76c207c09a422ec1753ba454d103..515b1ce1b78b9f4793844baf2686e346c40fbb09 100644
--- a/qt/widgets/common/test/DataProcessorUI/ProcessingAlgorithmBaseTest.h
+++ b/qt/widgets/common/test/DataProcessorUI/ProcessingAlgorithmBaseTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_DATAPROCESSORPROCESSINGALGORITHMBASETEST_H_
-#define MANTID_MANTIDWIDGETS_DATAPROCESSORPROCESSINGALGORITHMBASETEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -55,5 +54,3 @@ public:
     TS_ASSERT_EQUALS(alg.getInputWsProperties(), std::vector<QString>());
   }
 };
-
-#endif /* MANTID_MANTIDWIDGETS_DATAPROCESSORPROCESSINGALGORITHMBASETEST_H_ */
diff --git a/qt/widgets/common/test/DataProcessorUI/ProcessingAlgorithmTest.h b/qt/widgets/common/test/DataProcessorUI/ProcessingAlgorithmTest.h
index 65abea4d28791c57746b9d8c28da85b052effbf4..9ecff7d78a3735ad1ad19b47f51a97b608f30508 100644
--- a/qt/widgets/common/test/DataProcessorUI/ProcessingAlgorithmTest.h
+++ b/qt/widgets/common/test/DataProcessorUI/ProcessingAlgorithmTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_DATAPROCESSORPROCESSINGALGORITHMTEST_H
-#define MANTID_MANTIDWIDGETS_DATAPROCESSORPROCESSINGALGORITHMTEST_H
+#pragma once
 
 #include <QStringList>
 #include <cxxtest/TestSuite.h>
@@ -99,5 +98,4 @@ public:
   }
 
   // Add more tests for specific algorithms here
-};
-#endif /* MANTID_MANTIDWIDGETS_DATAPROCESSORPROCESSINGALGORITHMTEST_H */
+};
\ No newline at end of file
diff --git a/qt/widgets/common/test/DataProcessorUI/QOneLevelTreeModelTest.h b/qt/widgets/common/test/DataProcessorUI/QOneLevelTreeModelTest.h
index c9e2fe1364678907d81b4ee2fbb01b0ac4c08f15..542309ee4f83a6e10a5a7df5fb5916c9f0aeaead 100644
--- a/qt/widgets/common/test/DataProcessorUI/QOneLevelTreeModelTest.h
+++ b/qt/widgets/common/test/DataProcessorUI/QOneLevelTreeModelTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_QDATAPROCESSORONELEVELTREEMODELTEST_H
-#define MANTID_MANTIDWIDGETS_QDATAPROCESSORONELEVELTREEMODELTEST_H
+#pragma once
 
 #include "MantidAPI/ITableWorkspace.h"
 #include "MantidAPI/TableRow.h"
@@ -285,5 +284,3 @@ public:
 private:
   WhiteList m_whitelist;
 };
-
-#endif /* MANTID_MANTIDWIDGETS_QDATAPROCESSORONELEVELTREEMODELTEST_H */
diff --git a/qt/widgets/common/test/DataProcessorUI/QTwoLevelTreeModelTest.h b/qt/widgets/common/test/DataProcessorUI/QTwoLevelTreeModelTest.h
index f038301583cfaf8ee52f83e5bfe28b45321373d8..e3e9ef0e7a0877e21a9cfc9b572dee38d4509790 100644
--- a/qt/widgets/common/test/DataProcessorUI/QTwoLevelTreeModelTest.h
+++ b/qt/widgets/common/test/DataProcessorUI/QTwoLevelTreeModelTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_QDATAPROCESSORTWOLEVELTREEMODELTEST_H
-#define MANTID_MANTIDWIDGETS_QDATAPROCESSORTWOLEVELTREEMODELTEST_H
+#pragma once
 
 #include "MantidAPI/ITableWorkspace.h"
 #include "MantidAPI/TableRow.h"
@@ -851,5 +850,3 @@ public:
 private:
   WhiteList m_whitelist;
 };
-
-#endif /* MANTID_MANTIDWIDGETS_QDATAPROCESSORTWOLEVELTREEMODELTEST_H */
diff --git a/qt/widgets/common/test/DataProcessorUI/TwoLevelTreeManagerTest.h b/qt/widgets/common/test/DataProcessorUI/TwoLevelTreeManagerTest.h
index 89218dc500139c37a0e4dea0a5304b81f00b2e94..e2c445031710975dc838f55e0e32e05104bdfe1a 100644
--- a/qt/widgets/common/test/DataProcessorUI/TwoLevelTreeManagerTest.h
+++ b/qt/widgets/common/test/DataProcessorUI/TwoLevelTreeManagerTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_DATAPROCESSORTWOLEVELTREEMANAGERTEST_H
-#define MANTID_MANTIDWIDGETS_DATAPROCESSORTWOLEVELTREEMANAGERTEST_H
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 #include <gmock/gmock.h>
@@ -474,5 +473,4 @@ public:
     TS_ASSERT_EQUALS(data[1][0]->data(), newRow);
     TS_ASSERT_EQUALS(data[1][1]->data(), newRow);
   }
-};
-#endif /* MANTID_MANTIDWIDGETS_DATAPROCESSORTWOLEVELTREEMANAGERTEST_H */
+};
\ No newline at end of file
diff --git a/qt/widgets/common/test/DataProcessorUI/WhiteListTest.h b/qt/widgets/common/test/DataProcessorUI/WhiteListTest.h
index a7ff5e6976b32a8b89f82de59401fb36bbdab618..3a9db6568ca5af3bfda797976eaba503ea6d7b60 100644
--- a/qt/widgets/common/test/DataProcessorUI/WhiteListTest.h
+++ b/qt/widgets/common/test/DataProcessorUI/WhiteListTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_DATAPROCESSORWHITELISTTEST_H
-#define MANTID_MANTIDWIDGETS_DATAPROCESSORWHITELISTTEST_H
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 #include <gmock/gmock.h>
@@ -127,5 +126,4 @@ public:
     TS_ASSERT_EQUALS(whitelist.prefix(0), "");
     TS_ASSERT_EQUALS(whitelist.prefix(1), "blah");
   }
-};
-#endif /* MANTID_MANTIDWIDGETS_DATAPROCESSORWHITELISTTEST_H */
+};
\ No newline at end of file
diff --git a/qt/widgets/common/test/FileDialogHandlerTest.h b/qt/widgets/common/test/FileDialogHandlerTest.h
index 81af5b9af54ec5ae64db4d4bcdcc8fa03fd4f224..7e517b28ffc2866d9257b0cbce5df5b0b1f79078 100644
--- a/qt/widgets/common/test/FileDialogHandlerTest.h
+++ b/qt/widgets/common/test/FileDialogHandlerTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_FILEDIALOGHANDLERTEST_H_
-#define MANTIDQT_API_FILEDIALOGHANDLERTEST_H_
+#pragma once
 
 #include "MantidQtWidgets/Common/FileDialogHandler.h"
 #include <cxxtest/TestSuite.h>
@@ -96,5 +95,3 @@ public:
     TS_ASSERT_EQUALS(expected, result4);
   }
 };
-
-#endif /* MANTIDQT_API_FILEDIALOGHANDLERTEST_H_ */
diff --git a/qt/widgets/common/test/FindFilesThreadPoolManagerTest.h b/qt/widgets/common/test/FindFilesThreadPoolManagerTest.h
index cc50d5fc4e2e342d1b31cd61bbfb128c051c34ff..d01ff276d54102c8ae7f8dde97d62217b41f9c66 100644
--- a/qt/widgets/common/test/FindFilesThreadPoolManagerTest.h
+++ b/qt/widgets/common/test/FindFilesThreadPoolManagerTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_FINDFILESTHREADPOOLMANAGERTEST_H_
-#define MANTIDQT_API_FINDFILESTHREADPOOLMANAGERTEST_H_
+#pragma once
 
 #include "MantidQtWidgets/Common/FindFilesThreadPoolManager.h"
 #include "MantidQtWidgets/Common/FindFilesThreadPoolManagerMockObjects.h"
@@ -128,5 +127,3 @@ public:
     TS_ASSERT_EQUALS(results.filenames[0], exp_results.filenames[0])
   }
 };
-
-#endif /* MANTIDQT_API_FINDFILESTHREADPOOLMANAGERTEST */
diff --git a/qt/widgets/common/test/FindFilesWorkerTest.h b/qt/widgets/common/test/FindFilesWorkerTest.h
index 83732c822b04e613698dc29dfe74f8e719872b03..63a0cbe69e91ff36930ddbad5a09043c269cf9b0 100644
--- a/qt/widgets/common/test/FindFilesWorkerTest.h
+++ b/qt/widgets/common/test/FindFilesWorkerTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_FINDFILESWORKERTEST_H_
-#define MANTIDQT_API_FINDFILESWORKERTEST_H_
+#pragma once
 
 #include "MantidQtWidgets/Common/FindFilesThreadPoolManagerMockObjects.h"
 #include "MantidQtWidgets/Common/FindFilesWorker.h"
@@ -149,5 +148,3 @@ private:
     QCoreApplication::processEvents();
   }
 };
-
-#endif /* MANTIDQT_API_FINDFILESWORKERTEST */
diff --git a/qt/widgets/common/test/FunctionBrowserUtilsTest.h b/qt/widgets/common/test/FunctionBrowserUtilsTest.h
index e5e9062c4c36c3b752ca8a44d1626d800070d2ed..b63311bb16e8fe50ff42bc60a9ba4612ec49a6f8 100644
--- a/qt/widgets/common/test/FunctionBrowserUtilsTest.h
+++ b/qt/widgets/common/test/FunctionBrowserUtilsTest.h
@@ -5,8 +5,7 @@
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
 
-#ifndef MANTIDWIDGETS_FUNCTIONBROWSERUTILSTEST_H_
-#define MANTIDWIDGETS_FUNCTIONBROWSERUTILSTEST_H_
+#pragma once
 
 #include "MantidAPI/FrameworkManager.h"
 #include "MantidQtWidgets/Common/FunctionBrowser/FunctionBrowserUtils.h"
@@ -58,5 +57,4 @@ public:
         std::make_pair(QString(""), std::make_pair(QString(""), QString("")));
     TS_ASSERT_EQUALS(splitConstraints, expected_value);
   }
-};
-#endif // MANTIDWIDGETS_FUNCTIONBROWSERUTILSTEST_H_
\ No newline at end of file
+};
\ No newline at end of file
diff --git a/qt/widgets/common/test/FunctionModelTest.h b/qt/widgets/common/test/FunctionModelTest.h
index 4f72ba4a930c6e2515999aadd3282d840ce2f797..bd7477a1f102e8f853b5d6c8001b681551e0afa7 100644
--- a/qt/widgets/common/test/FunctionModelTest.h
+++ b/qt/widgets/common/test/FunctionModelTest.h
@@ -5,8 +5,7 @@
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
 
-#ifndef MANTIDWIDGETS_FUNCTIONMODELTEST_H_
-#define MANTIDWIDGETS_FUNCTIONMODELTEST_H_
+#pragma once
 
 #include "MantidAPI/FrameworkManager.h"
 #include "MantidAPI/FunctionFactory.h"
@@ -252,5 +251,3 @@ public:
     }
   }
 };
-
-#endif // MANTIDWIDGETS_FUNCTIONMODELTEST_H_
diff --git a/qt/widgets/common/test/FunctionMultiDomainPresenterTest.h b/qt/widgets/common/test/FunctionMultiDomainPresenterTest.h
index 541598844ccf29a2a8fd72d5c56075523973041a..b1157c5b1b7236c78440721545c0a587bb8b5e9e 100644
--- a/qt/widgets/common/test/FunctionMultiDomainPresenterTest.h
+++ b/qt/widgets/common/test/FunctionMultiDomainPresenterTest.h
@@ -5,8 +5,7 @@
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
 
-#ifndef MANTIDWIDGETS_FUNCTIONMULTIDOMAINPRESENTERTEST_H_
-#define MANTIDWIDGETS_FUNCTIONMULTIDOMAINPRESENTERTEST_H_
+#pragma once
 
 #include "MantidAPI/CompositeFunction.h"
 #include "MantidAPI/FrameworkManager.h"
@@ -516,5 +515,3 @@ public:
     TS_ASSERT_EQUALS(locals[0], "A1");
   }
 };
-
-#endif // MANTIDWIDGETS_FUNCTIONMULTIDOMAINPRESENTERTEST_H_
diff --git a/qt/widgets/common/test/InterfaceManagerTest.h b/qt/widgets/common/test/InterfaceManagerTest.h
index 68734d15eec2e120dedb25bffae998b2c504e283..8ecb7ee79f1ff90ade1a7fe664f40c4e75c728cd 100644
--- a/qt/widgets/common/test/InterfaceManagerTest.h
+++ b/qt/widgets/common/test/InterfaceManagerTest.h
@@ -11,8 +11,7 @@
  *      Author: spu92482
  */
 
-#ifndef INTERFACEMANAGERTEST_H_
-#define INTERFACEMANAGERTEST_H_
+#pragma once
 
 #include "MantidKernel/Exception.h"
 #include "MantidQtWidgets/Common/InterfaceManager.h"
@@ -28,5 +27,3 @@ public:
     TS_ASSERT_DIFFERS(&objA, &objB);
   }
 };
-
-#endif /* INTERFACEMANAGERTEST_H_ */
diff --git a/qt/widgets/common/test/LogValueFinderTest.h b/qt/widgets/common/test/LogValueFinderTest.h
index e4b894cc68132f34ac8ff720a76de95e4b0aecc3..d9adbc49d0d3f6bb50d10c93b297ff2ef32c4fe0 100644
--- a/qt/widgets/common/test/LogValueFinderTest.h
+++ b/qt/widgets/common/test/LogValueFinderTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_CUSTOMINTERFACES_MDFLOGVALUEFINDERTEST_H_
-#define MANTIDQT_CUSTOMINTERFACES_MDFLOGVALUEFINDERTEST_H_
+#pragma once
 
 #include "MantidAPI/MatrixWorkspace.h"
 #include "MantidAPI/Run.h"
@@ -165,5 +164,3 @@ private:
     return ws;
   }
 };
-
-#endif /* MANTIDQT_CUSTOMINTERFACES_MDFLOGVALUEFINDERTEST_H_ */
diff --git a/qt/widgets/common/test/MockScriptRepository.h b/qt/widgets/common/test/MockScriptRepository.h
index ef50f44e21aca32c02675c37d80519df41c3acb6..5a9821334cc9f44ff2053edbfd9f9105ad9cac5e 100644
--- a/qt/widgets/common/test/MockScriptRepository.h
+++ b/qt/widgets/common/test/MockScriptRepository.h
@@ -5,8 +5,7 @@
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
 
-#ifndef MANTIDWIDGETS_MOCKSCRIPTREPOSITORY_H_
-#define MANTIDWIDGETS_MOCKSCRIPTREPOSITORY_H_
+#pragma once
 
 #include "MantidAPI/ScriptRepository.h"
 #include "MantidKernel/WarningSuppressions.h"
@@ -84,5 +83,4 @@ private:
   }
 };
 
-GNU_DIAG_ON_SUGGEST_OVERRIDE
-#endif /*MANTIDWIDGETS_MOCKSCRIPTREPOSITORY_H_ */
+GNU_DIAG_ON_SUGGEST_OVERRIDE
\ No newline at end of file
diff --git a/qt/widgets/common/test/NonOrthogonalTest.h b/qt/widgets/common/test/NonOrthogonalTest.h
index a3efd7f908148f8f9ec8df28c0968d8397648000..ba816d40ef125ee5d73b58a2c1fd204fccdb0ffe 100644
--- a/qt/widgets/common/test/NonOrthogonalTest.h
+++ b/qt/widgets/common/test/NonOrthogonalTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_NONORTHOGONALTEST_H_
-#define MANTIDQT_API_NONORTHOGONALTEST_H_
+#pragma once
 
 #include "MantidAPI/AlgorithmManager.h"
 #include "MantidAPI/FrameworkManager.h"
@@ -292,5 +291,3 @@ private:
 
   enum DimensionIndex { DimX = 0, DimY = 1, SliceDim = 2 };
 };
-
-#endif /* MANTIDQT_API_NONORTHOGONALTEST_H_ */
diff --git a/qt/widgets/common/test/ParseKeyValueStringTest.h b/qt/widgets/common/test/ParseKeyValueStringTest.h
index 71eabe79128397af89d5f673bfb79d34385c18b8..153d453583547b524b69122262d9b2f600e8ef12 100644
--- a/qt/widgets/common/test/ParseKeyValueStringTest.h
+++ b/qt/widgets/common/test/ParseKeyValueStringTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_PARSEKEYVALUESTRINGTEST_H
-#define MANTID_MANTIDWIDGETS_PARSEKEYVALUESTRINGTEST_H
+#pragma once
 
 #include "MantidQtWidgets/Common/ParseKeyValueString.h"
 #include <cxxtest/TestSuite.h>
@@ -102,5 +101,3 @@ private:
     TS_ASSERT_EQUALS(kvp["g"], "'");
   }
 };
-
-#endif // MANTID_MANTIDWIDGETS_PARSEKEYVALUESTRINGTEST_H
diff --git a/qt/widgets/common/test/PlotAxisTest.h b/qt/widgets/common/test/PlotAxisTest.h
index 1d3e667c6d535322ade0ea9389bc84205d061976..38412bc1ff0061c846d9156a62af41c09ec45c78 100644
--- a/qt/widgets/common/test/PlotAxisTest.h
+++ b/qt/widgets/common/test/PlotAxisTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_API_PLOTAXISLABELTEST_H_
-#define MANTID_API_PLOTAXISLABELTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -198,5 +197,3 @@ public:
     TS_ASSERT_THROWS(PlotAxis(*ws, -1), const std::invalid_argument &);
   }
 };
-
-#endif /* MANTID_API_PLOTAXISLABELTEST_H_ */
diff --git a/qt/widgets/common/test/ProgressableViewTest.h b/qt/widgets/common/test/ProgressableViewTest.h
index 47bfd4a671ddcad857a8cdc9301b3398546ee41e..dd3d0d3a577c66e724882db1ca10c19290f00e1a 100644
--- a/qt/widgets/common/test/ProgressableViewTest.h
+++ b/qt/widgets/common/test/ProgressableViewTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_PROGRESSABLEVIEWTEST_H
-#define MANTID_MANTIDWIDGETS_PROGRESSABLEVIEWTEST_H
+#pragma once
 
 #include "MantidQtWidgets/Common/ProgressableView.h"
 #include <cxxtest/TestSuite.h>
@@ -86,5 +85,3 @@ private:
 
   ProgressBar m_progress;
 };
-
-#endif /*MANTID_MANTIDWIDGETS_PROGRESSABLEVIEWTEST_H */
diff --git a/qt/widgets/common/test/ProjectSaveMockObjects.h b/qt/widgets/common/test/ProjectSaveMockObjects.h
index 8f085fe618b532a353d38fd12dff448e4ff6e658..44d2a4027c41acd6029b35b0979a193a64d08a07 100644
--- a/qt/widgets/common/test/ProjectSaveMockObjects.h
+++ b/qt/widgets/common/test/ProjectSaveMockObjects.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGETS_PROJECTSAVEMOCKOBJECTS_H
-#define MANTIDQT_MANTIDWIDGETS_PROJECTSAVEMOCKOBJECTS_H
+#pragma once
 
 #include "MantidKernel/WarningSuppressions.h"
 #include "MantidQtWidgets/Common/IProjectSaveView.h"
@@ -62,5 +61,3 @@ public:
 
   std::string getWindowType() override { return "Matrix"; }
 };
-
-#endif
diff --git a/qt/widgets/common/test/ProjectSaveModelTest.h b/qt/widgets/common/test/ProjectSaveModelTest.h
index d620980862af321ece4dbfe0538c7103b2fd92b7..4f00fab4532c9ac3ca3ef915dfaeb785f3d4abc6 100644
--- a/qt/widgets/common/test/ProjectSaveModelTest.h
+++ b/qt/widgets/common/test/ProjectSaveModelTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGETS_PROJECTSAVEMODELTEST_H
-#define MANTIDQT_MANTIDWIDGETS_PROJECTSAVEMODELTEST_H
+#pragma once
 
 #include "MantidAPI/Workspace.h"
 #include "MantidKernel/WarningSuppressions.h"
@@ -322,5 +321,3 @@ public:
     TS_ASSERT_EQUALS(model.getProjectSize(workspaceNames), assumedSize);
   }
 };
-
-#endif // MANTIDQT_MANTIDWIDGETS_PROJECTSAVEMODELTEST_H
diff --git a/qt/widgets/common/test/ProjectSavePresenterTest.h b/qt/widgets/common/test/ProjectSavePresenterTest.h
index 556b546cd1993a1560f86846b22e9ac4f275cdf5..04630f15d03f6b603f4d2ffb40b31372be4cdfe1 100644
--- a/qt/widgets/common/test/ProjectSavePresenterTest.h
+++ b/qt/widgets/common/test/ProjectSavePresenterTest.h
@@ -5,8 +5,7 @@
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
 
-#ifndef MANTIDQT_MANTIDWIDGETS_PROJECTSAVEPRESENTERTEST_H
-#define MANTIDQT_MANTIDWIDGETS_PROJECTSAVEPRESENTERTEST_H
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 #include <gmock/gmock.h>
@@ -362,5 +361,3 @@ public:
     }
   }
 };
-
-#endif
diff --git a/qt/widgets/common/test/Python/SipTest.h b/qt/widgets/common/test/Python/SipTest.h
index 72b1e27880ea18e1511943bef4757837fdffd01d..df4238bc0e176fe3b99c70e77897d28c798a08ed 100644
--- a/qt/widgets/common/test/Python/SipTest.h
+++ b/qt/widgets/common/test/Python/SipTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTWIDGETS_SIPTEST_H
-#define MANTIDQTWIDGETS_SIPTEST_H
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -63,5 +62,3 @@ public:
         const std::runtime_error &);
   }
 };
-
-#endif // MANTIDQTWIDGETS_SIPTEST_H
diff --git a/qt/widgets/common/test/QtJSONUtilsTest.h b/qt/widgets/common/test/QtJSONUtilsTest.h
index 751f8bb3d4405810d1ecffbfebcda1814dfc77d6..a29bd5b9b0f9f07f73aaf75757f3b8d12e75bb4a 100644
--- a/qt/widgets/common/test/QtJSONUtilsTest.h
+++ b/qt/widgets/common/test/QtJSONUtilsTest.h
@@ -5,8 +5,7 @@
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
 
-#ifndef MANTIDQT_MANTIDWIDGETS_QTJSONUTILSTEST_H
-#define MANTIDQT_MANTIDWIDGETS_QTJSONUTILSTEST_H
+#pragma once
 
 #include "MantidQtWidgets/Common/QtJSONUtils.h"
 
@@ -78,5 +77,3 @@ private:
                      map1[QString("list")].toList())
   }
 };
-
-#endif /* MANTIDQT_MANTIDWIDGETS_QTJSONUTILSTEST_H */
\ No newline at end of file
diff --git a/qt/widgets/common/test/RepoModelTest.h b/qt/widgets/common/test/RepoModelTest.h
index ec006fd20597b49e015a5ea2a3e43c12bf0620d7..5c59bbdc841ef8a134b06d75853aa08066f13499 100644
--- a/qt/widgets/common/test/RepoModelTest.h
+++ b/qt/widgets/common/test/RepoModelTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDWIDGETS_REPOMODELTEST_H_
-#define MANTIDWIDGETS_REPOMODELTEST_H_
+#pragma once
 
 #include "MantidKernel/ConfigService.h"
 #include <cxxtest/TestSuite.h>
@@ -229,5 +228,3 @@ private:
     }
   }
 };
-
-#endif /* MANTIDWIDGETS_REPOMODELTEST_H_ */
diff --git a/qt/widgets/common/test/SelectionNotificationServiceTest.h b/qt/widgets/common/test/SelectionNotificationServiceTest.h
index e9fae4e4430be38281dcb8b7f69da641363273e8..66b3c63b63ba1b5af72f57e0108ee56b763ab588 100644
--- a/qt/widgets/common/test/SelectionNotificationServiceTest.h
+++ b/qt/widgets/common/test/SelectionNotificationServiceTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_SELECTION_NOTIFICATION_SERVICE_H_
-#define MANTIDQT_API_SELECTION_NOTIFICATION_SERVICE_H_
+#pragma once
 
 #include "MantidQtWidgets/Common/SelectionNotificationService.h"
 #include <cxxtest/TestSuite.h>
@@ -20,5 +19,3 @@ public:
             .sendQPointSelection(false, 1, 2, 3));
   }
 };
-
-#endif /* MANTIDQT_API_SELECTION_NOTIFICATION_SERVICE_H_ */
diff --git a/qt/widgets/common/test/SignalBlockerTest.h b/qt/widgets/common/test/SignalBlockerTest.h
index c3cb3e5579ff5065e0b3ef27ca194fd252c59741..1ec3c539f4f8e99f52bc5e438b2afd7151001a56 100644
--- a/qt/widgets/common/test/SignalBlockerTest.h
+++ b/qt/widgets/common/test/SignalBlockerTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_API_SIGNALBLOCKERTEST_H_
-#define MANTID_API_SIGNALBLOCKERTEST_H_
+#pragma once
 
 #include "MantidQtWidgets/Common/SignalBlocker.h"
 #include <QObject>
@@ -30,5 +29,3 @@ public:
     delete toBlock;
   }
 };
-
-#endif /* MANTID_API_SIGNALBLOCKERTEST_H_ */
diff --git a/qt/widgets/common/test/TrackedActionTest.h b/qt/widgets/common/test/TrackedActionTest.h
index 74206f9703e1e65fad4fef27866c98e05a45f39d..62e7d23466db9302b7f9d4cabaddac3ccf4f2b89 100644
--- a/qt/widgets/common/test/TrackedActionTest.h
+++ b/qt/widgets/common/test/TrackedActionTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_TRACKEDACTIONEST_H_
-#define MANTID_MANTIDWIDGETS_TRACKEDACTIONEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -92,5 +91,3 @@ public:
                       "ShouldNotTrack"); // Should not have tracked
   }
 };
-
-#endif /* MANTID_MANTIDWIDGETS_TRACKEDACTIONEST_H_ */
\ No newline at end of file
diff --git a/qt/widgets/common/test/UserInputValidatorTest.h b/qt/widgets/common/test/UserInputValidatorTest.h
index ab2af23b11c6e6526429ebbe086d06bf1610a280..78cdbbf8f1e61aab61ca0f71f4c1ee9ec255934d 100644
--- a/qt/widgets/common/test/UserInputValidatorTest.h
+++ b/qt/widgets/common/test/UserInputValidatorTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_CUSTOMINTERFACES_USERINPUTVALIDATORTEST_H
-#define MANTID_CUSTOMINTERFACES_USERINPUTVALIDATORTEST_H
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 #include <string>
@@ -143,5 +142,3 @@ public:
                      "completely enclose inner range.");
   }
 };
-
-#endif
diff --git a/qt/widgets/common/test/WidgetsCommonTestInitialization.h b/qt/widgets/common/test/WidgetsCommonTestInitialization.h
index 5ab3f685be627715fac3e1ebc874f6f97a91d4e9..3c30ac94a192a2bbdea92b91c69cf8203392af10 100644
--- a/qt/widgets/common/test/WidgetsCommonTestInitialization.h
+++ b/qt/widgets/common/test/WidgetsCommonTestInitialization.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef WIDGETSCOMMONTESTINITIALIZATION_H
-#define WIDGETSCOMMONTESTINITIALIZATION_H
+#pragma once
 
 #include "MantidQtWidgets/Common/Testing/QApplicationGlobalFixture.h"
 
@@ -16,5 +15,3 @@
 // statements do not cause multiple-definition errors.
 //------------------------------------------------------------------------------
 static QApplicationGlobalFixture WIDGETS_COMMON_QAPP;
-
-#endif // WIDGETSCOMMONTESTINITIALIZATION_H
diff --git a/qt/widgets/factory/inc/MantidQtWidgets/Factory/DllOption.h b/qt/widgets/factory/inc/MantidQtWidgets/Factory/DllOption.h
index a7404e7f3911e726361684f38dad086a9dc105df..510d413c0cc596c6e4c71bc9d01db34e76202d59 100644
--- a/qt/widgets/factory/inc/MantidQtWidgets/Factory/DllOption.h
+++ b/qt/widgets/factory/inc/MantidQtWidgets/Factory/DllOption.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_FACTORY_DLLOPTION_H_
-#define MANTIDQT_FACTORY_DLLOPTION_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 
@@ -14,5 +13,3 @@
 #else
 #define EXPORT_OPT_MANTIDQT_FACTORY DLLImport
 #endif /* IN_MANTIDQT_API */
-
-#endif // MANTIDQT_FACTORY_DLLOPTION_H_
diff --git a/qt/widgets/factory/inc/MantidQtWidgets/Factory/WidgetFactory.h b/qt/widgets/factory/inc/MantidQtWidgets/Factory/WidgetFactory.h
index 1153dcada723a34f24d5c64d208f59a1b3aeeefc..c079f3369e207d50d6a9ddc3eab61570c3ff0bfa 100644
--- a/qt/widgets/factory/inc/MantidQtWidgets/Factory/WidgetFactory.h
+++ b/qt/widgets/factory/inc/MantidQtWidgets/Factory/WidgetFactory.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_FACTORY_WIDGETFACTORY_H_
-#define MANTID_FACTORY_WIDGETFACTORY_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidKernel/SingletonHolder.h"
@@ -56,5 +55,3 @@ protected:
 
 } // namespace Factory
 } // namespace MantidQt
-
-#endif /* MANTID_FACTORY_WIDGETFACTORY_H_ */
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/BankRenderingHelpers.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/BankRenderingHelpers.h
index 983ca90acfa23057442a5d8d9c65a9997c197478..d5cf760e310142fa84cca9c492f11ece7971b754 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/BankRenderingHelpers.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/BankRenderingHelpers.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef BANKRENDERINGHELPERS_H
-#define BANKRENDERINGHELPERS_H
+#pragma once
 #include "DllOption.h"
 #include "MantidQtWidgets/InstrumentView/GLColor.h"
 #include "MantidQtWidgets/InstrumentView/GridTextureFace.h"
@@ -58,5 +57,3 @@ renderStructuredBank(const Mantid::Geometry::ComponentInfo &compInfo,
 } // namespace BankRenderingHelpers
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // BANKRENDERINGHELPERS_H
\ No newline at end of file
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/BankTextureBuilder.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/BankTextureBuilder.h
index d73d1c1acd305e9cd25f6a72f3ae8da1d9739188..07ec22b7b7c268598978d79bb8d703db72c93b98 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/BankTextureBuilder.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/BankTextureBuilder.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef BANKTEXTUREBUILDER_H
-#define BANKTEXTUREBUILDER_H
+#pragma once
 
 #include "GLColor.h"
 #include "MantidBeamline/ComponentType.h"
@@ -67,5 +66,4 @@ private:
 };
 } // namespace detail
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif
\ No newline at end of file
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/BaseCustomInstrumentModel.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/BaseCustomInstrumentModel.h
index 7669ac7266d7e406c2dc2592df89d6cf3d466138..0a7bacf1fc0415883183657b69ad4f2f0766a195 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/BaseCustomInstrumentModel.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/BaseCustomInstrumentModel.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_INSTRUMENTVIEW_BASECUSTOMINSTRUMENTMODEL_H_
-#define MANTIDQT_INSTRUMENTVIEW_BASECUSTOMINSTRUMENTMODEL_H_
+#pragma once
 
 #include "DllOption.h"
 
@@ -40,5 +39,3 @@ protected:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTIDQT_INSTRUMENTVIEW_BASEINSTRUMENTMODEL_H_ */
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/BaseCustomInstrumentPresenter.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/BaseCustomInstrumentPresenter.h
index daad1941f388f94a7d55b634cd1ad24f277520b9..102bca51e2d24021419cc45df4f18e1e540b3b7b 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/BaseCustomInstrumentPresenter.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/BaseCustomInstrumentPresenter.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_INSTRUMENTVIEW_BASECUSTOMINSTRUMENTPRESENTER_H_
-#define MANTIDQT_INSTRUMENTVIEW_BASECUSTOMINSTRUMENTPRESENTER_H_
+#pragma once
 #include "DllOption.h"
 #include "MantidQtWidgets/Common/ObserverPattern.h"
 #include "MantidQtWidgets/InstrumentView/BaseCustomInstrumentModel.h"
@@ -59,5 +58,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTIDQT_INSTRUMENTVIEW_BaseCustomInstrumentPresenter_H_ */
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/BaseCustomInstrumentView.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/BaseCustomInstrumentView.h
index b1ad37f0995c23c9261bd386b2c7ea82f8c3f301..ad87b4db9e8ce9b9d95c8cd97de1fec8854cb58f 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/BaseCustomInstrumentView.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/BaseCustomInstrumentView.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_INSTRUMENTVIEW_BASECUSTOMINSTRUMENTVIEW_H_
-#define MANTIDQT_INSTRUMENTVIEW_BASECUSTOMINSTRUMENTVIEW_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidQtWidgets/Common/MWRunFiles.h"
@@ -67,5 +66,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTIDQT_INSTRUMENTVIEW_BASECUSTOMINSTRUMENTVIEW_H_ */
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/BinDialog.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/BinDialog.h
index a437753d122f44632933820ae361234eb65ae829..7dbbe6510fafe337f2a053e3b98bdd408b70669e 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/BinDialog.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/BinDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef BINDIALOG_H_
-#define BINDIALOG_H_
+#pragma once
 
 #include <QCheckBox>
 #include <QDialog>
@@ -52,5 +51,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*BINDIALOG_H_*/
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/CollapsiblePanel.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/CollapsiblePanel.h
index 749310a614afa29c5dc6f15a1b61597c46de8f64..42b5d71ab00b215637bdff1f9131e4f29d7fb78a 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/CollapsiblePanel.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/CollapsiblePanel.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef COLLAPSIBLEPANEL_H_
-#define COLLAPSIBLEPANEL_H_
+#pragma once
 
 #include <QLabel>
 #include <QWidget>
@@ -70,5 +69,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*COLLAPSIBLEPANEL_H_*/
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/ColorBar.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/ColorBar.h
index bd1dc54fe9c667f1601f320fcc61536645bca3b1..937fe790ca2c979ede5b4b41528abf4520148460 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/ColorBar.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/ColorBar.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_WIDGETS_INSTRUMENTVIEW_COLORBAR_H
-#define MANTIDQT_WIDGETS_INSTRUMENTVIEW_COLORBAR_H
+#pragma once
 
 #include <QtGlobal>
 
@@ -24,5 +23,3 @@ using ColorBar = MantidQt::Widgets::MplCpp::ColorbarWidget;
 #endif
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQT_WIDGETS_INSTRUMENTVIEW_COLORBAR_H
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/ColorMap.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/ColorMap.h
index deeb7da80b1e9fb8638f0002cb6692eb04553262..45fdec7d4ed01aacb6305c444654ea6feaaa0105 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/ColorMap.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/ColorMap.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_WIDGETS_INSTRUMENTVIEW_COLORMAP_H
-#define MANTIDQT_WIDGETS_INSTRUMENTVIEW_COLORMAP_H
+#pragma once
 
 #include <QtGlobal>
 
@@ -24,5 +23,3 @@ using ColorMap = MantidQt::Widgets::MplCpp::MantidColorMap;
 #endif
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQT_WIDGETS_INSTRUMENTVIEW_COLORMAP_H
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/DetXMLFile.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/DetXMLFile.h
index 0be2e5746070d07d5f1c3ea628c6f69835952b9e..eeb39a3b6bfeb9f011194dad4262b3f307202ad6 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/DetXMLFile.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/DetXMLFile.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DETXMLFILE_H
-#define DETXMLFILE_H
+#pragma once
 
 #include <QList>
 #include <QString>
@@ -54,5 +53,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // DETXMLFILE_H
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/DllOption.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/DllOption.h
index a74f780ac6d050801354c69b3627f9e2e929f9eb..3a83f5a2a0f1e61fa7bea8fa7b2a73acc62441a5 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/DllOption.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/DllOption.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_INSTRUMENTVIEW_DLLOPTION_H_
-#define MANTIDQT_INSTRUMENTVIEW_DLLOPTION_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 
@@ -16,5 +15,3 @@
 #define EXPORT_OPT_MANTIDQT_INSTRUMENTVIEW DLLImport
 #define EXTERN_MANTIDQT_INSTRUMENTVIEW extern
 #endif /* IN_MANTIDQT_INSTRUMENTVIEW */
-
-#endif // MANTIDQT_INSTRUMENTVIEW_DLLOPTION_H_
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/GLColor.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/GLColor.h
index e5091cab89d3a325208de093c2161182c337c7a2..4a26ddea452d3fcc926256ee5baed902df3be6d8 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/GLColor.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/GLColor.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef GLCOLOR_H_
-#define GLCOLOR_H_
+#pragma once
 
 #include <iosfwd>
 
@@ -55,5 +54,3 @@ private:
 std::ostream &operator<<(std::ostream &ostr, const GLColor &c);
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*GLCOLOR_H_*/
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/GLObject.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/GLObject.h
index b37ab07d21b283212f4fed1915d786f0efc7d824..7ea9ded44c6957714e199d46b00305732eff7a63 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/GLObject.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/GLObject.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDPLOT_GLOBJECT_H_
-#define MANTIDPLOT_GLOBJECT_H_
+#pragma once
 
 #include "MantidGeometry/Rendering/OpenGL_Headers.h"
 #include <string>
@@ -58,5 +57,3 @@ protected:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*MANTIDPLOT_GLOBJECT_H*/
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/GridTextureFace.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/GridTextureFace.h
index 1b717783bddc675f12c5c7473d31b3bcb7bce0dd..825d58703b404b2daf63cc0657a784c4b03f74ed 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/GridTextureFace.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/GridTextureFace.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef GRIDTEXTUREFACE_H
-#define GRIDTEXTUREFACE_H
+#pragma once
 namespace MantidQt {
 namespace MantidWidgets {
 
@@ -14,5 +13,4 @@ namespace detail {
 enum class GridTextureFace { Front = 0, Back, Left, Right, Top, Bottom };
 }
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // GRIDTEXTUREFACE_H
\ No newline at end of file
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentActor.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentActor.h
index ac51905b910a1fda3bb742b65535b3c4b61fd5c0..7f23fc3d6a3abf74b07bd8452c7ca88aeccd5005 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentActor.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentActor.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef INSTRUMENTACTOR_H_
-#define INSTRUMENTACTOR_H_
+#pragma once
 
 #include "MantidQtWidgets/InstrumentView/ColorMap.h"
 #include "MantidQtWidgets/InstrumentView/DllOption.h"
@@ -293,5 +292,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*InstrumentActor_H_*/
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentRenderer.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentRenderer.h
index a9106b111f1b24cebf74d4d90d3c4665d7b4eda3..b087d0bb79619c4f9ea8b612f25a81a982b5845b 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentRenderer.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentRenderer.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef INSTRUMENTRENDERER_H_
-#define INSTRUMENTRENDERER_H_
+#pragma once
 
 #include "ColorMap.h"
 #include "DllOption.h"
@@ -77,5 +76,4 @@ private:
   void drawSingleDetector(size_t detIndex, bool picking);
 };
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif // INSTRUMENTRENDERER_H_
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentTreeModel.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentTreeModel.h
index 813a691bd11a926f225245ef4bf63e7b0a367918..e994cd5cede11f8c2055112d31dae58a8b4923d3 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentTreeModel.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentTreeModel.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef INSTRUMENTTREEMODEL_H
-#define INSTRUMENTTREEMODEL_H
+#pragma once
 
 #include "MantidQtWidgets/InstrumentView/InstrumentWidget.h"
 
@@ -48,5 +47,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // INSTRUMENTTREEMODEL_H
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentTreeWidget.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentTreeWidget.h
index 48d2f5e94291cda7c37da08c1b361b430fb46cf1..b4ee71e9cb1e66451d25e21c4fc7180220cd330f 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentTreeWidget.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentTreeWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef INSTRUMENTTREEWIDGET_H
-#define INSTRUMENTTREEWIDGET_H
+#pragma once
 
 //---------------------------------------
 // Includes
@@ -50,5 +49,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // INSTRUMENTTREEWIDGET_H
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidget.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidget.h
index 918be2a96c71bcd279e14166fb411d9ba302db31..a02fa97df25ef9a27c923d13653789dde3650d0f 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidget.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef INSTRUMENTWIDGET_H_
-#define INSTRUMENTWIDGET_H_
+#pragma once
 
 #include "DllOption.h"
 #include "InstrumentWidgetTypes.h"
@@ -346,5 +345,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*INSTRUMENTWIDGET_H_*/
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetDecoder.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetDecoder.h
index 19e979cfa3471ba5488d9ca40cc160ea463bb0dc..5955aa7f9319a77fc64fcfe0d76cc00a4cb44de4 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetDecoder.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetDecoder.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_WIDGETS_INSTRUMENTWIDGETDECODER_H_
-#define MANTIDQT_WIDGETS_INSTRUMENTWIDGETDECODER_H_
+#pragma once
 
 #include "MantidQtWidgets/InstrumentView/ColorBar.h"
 #include "MantidQtWidgets/InstrumentView/InstrumentActor.h"
@@ -83,5 +82,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*MANTIDQT_WIDGETS_INSTRUMENTWIDGETDECODER_H_*/
\ No newline at end of file
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetEncoder.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetEncoder.h
index e9d0f010c68a28ff5788a45067bfb926c04295f1..a7a76b1c5389428bc3b58431839ddf08d4c7e631 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetEncoder.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetEncoder.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_WIDGETS_INSTRUMENTWIDGETENCODER_H_
-#define MANTIDQT_WIDGETS_INSTRUMENTWIDGETENCODER_H_
+#pragma once
 
 #include "MantidQtWidgets/InstrumentView/ColorBar.h"
 #include "MantidQtWidgets/InstrumentView/InstrumentActor.h"
@@ -75,5 +74,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*MANTIDQT_WIDGETS_INSTRUMENTWIDGETENCODER_H_*/
\ No newline at end of file
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetMaskTab.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetMaskTab.h
index e909486d3c339eb8bda6046c631d09cf959a0a37..0ea00c95d453cd1495aa9d5b9449e1113e3cd0a4 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetMaskTab.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetMaskTab.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef INSTRUMENTWIDGETMASKTAB_H_
-#define INSTRUMENTWIDGETMASKTAB_H_
+#pragma once
 
 #include "MantidGeometry/Instrument.h"
 #include "MantidQtWidgets/InstrumentView/InstrumentWidgetTab.h"
@@ -214,5 +213,3 @@ protected:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*INSTRUMENTWIDGETMASKTAB_H_*/
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetPickTab.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetPickTab.h
index c01fd6609281a7c1c7d25b417092d18e12432006..7ed82994009979a288cd3138c32d6a8b235722cb 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetPickTab.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetPickTab.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef INSTRUMENTWIDGETPICKTAB_H_
-#define INSTRUMENTWIDGETPICKTAB_H_
+#pragma once
 
 #include "MantidQtWidgets/InstrumentView/InstrumentWidgetTab.h"
 #include "MantidQtWidgets/InstrumentView/MantidGLWidget.h"
@@ -299,5 +298,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*INSTRUMENTWIDGETPICKTAB_H_*/
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetRenderTab.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetRenderTab.h
index 1eb213b0b5ad542f3a714d6c011e6570a84a299a..58d5a627b64350eed052b93361569f10abc7dbd2 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetRenderTab.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetRenderTab.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef INSTRUMENTWIDGETRENDERTAB_H_
-#define INSTRUMENTWIDGETRENDERTAB_H_
+#pragma once
 
 #include "ColorBar.h"
 #include "ColorMap.h"
@@ -148,5 +147,4 @@ private: // members
   friend class InstrumentWidgetDecoder;
 };
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*INSTRUMENTWIDGETRENDERTAB_H_*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetTab.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetTab.h
index 3f1411a44d1c676b40bf60e4efd7c6b40c563958..cc8e44927afb4453e2548f731c2041750ab8598d 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetTab.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetTab.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef INSTRUMENTWIDGETTAB_H
-#define INSTRUMENTWIDGETTAB_H
+#pragma once
 
 #include "InstrumentWidgetTypes.h"
 
@@ -56,5 +55,3 @@ protected:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // INSTRUMENTWIDGETTAB_H
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetTreeTab.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetTreeTab.h
index b796c5676cfdafdd2e349f6b28a6042da9c54e82..7377f21dff66702f78b9ea78d3c2f44ddc2b49c0 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetTreeTab.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetTreeTab.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef INSTRUMENTWIDGETTREETAB_H_
-#define INSTRUMENTWIDGETTREETAB_H_
+#pragma once
 
 #include "InstrumentWidgetTab.h"
 
@@ -40,5 +39,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*INSTRUMENTWIDGETTREETAB_H_*/
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetTypes.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetTypes.h
index 357423757e446306e8175e8d730f305721fd63e9..5fc4b3426664ddad66a98a93476e8fbb349ec0a9 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetTypes.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/InstrumentWidgetTypes.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef INSTRUMENTWIDGETTYPES_H_
-#define INSTRUMENTWIDGETTYPES_H_
+#pragma once
 
 #include "DllOption.h"
 
@@ -28,5 +27,3 @@ public:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*INSTRUMENTWIDGETTYPES_H_*/
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/MantidGLWidget.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/MantidGLWidget.h
index 176e1c54db3e75c93bb8d2239bbe6845540cf6be..f1a3e03828cf127a89a62790dd63b30ace3039a7 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/MantidGLWidget.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/MantidGLWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDGLWIDGET_H_
-#define MANTIDGLWIDGET_H_
+#pragma once
 
 #include "MantidGeometry/IComponent.h"
 
@@ -72,5 +71,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*MANTIDGLWIDGET_H_*/
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/MaskBinsData.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/MaskBinsData.h
index ccff21c90636ea10634f82f6bf5e9ce0521f5f14..2962920c1e129c3777762ec1e653999aa1c44e4f 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/MaskBinsData.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/MaskBinsData.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MASKBINSDATA_H_
-#define MASKBINSDATA_H_
+#pragma once
 
 #include "MantidAPI/MatrixWorkspace_fwd.h"
 
@@ -50,5 +49,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*MASKBINSDATA_H_*/
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/MiniPlot.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/MiniPlot.h
index a2b830ebc865cb8c296cde07d0db12ab596a3a51..ba832de82fbe07990c2818a59aea35d103c3cfd8 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/MiniPlot.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/MiniPlot.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_WIDGETS_INSTRUMENTVIEW_MINIPLOT_H
-#define MANTIDQT_WIDGETS_INSTRUMENTVIEW_MINIPLOT_H
+#pragma once
 
 #include <QtGlobal>
 
@@ -24,5 +23,3 @@ using MiniPlot = MiniPlotMpl;
 #endif
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQT_WIDGETS_INSTRUMENTVIEW_MINIPLOT_H
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/MiniPlotMpl.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/MiniPlotMpl.h
index b80a5cd934f4f54b8223af5dc26dddc58c8229af..0a01557a069211ed2ece02ece441068e75d5430c 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/MiniPlotMpl.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/MiniPlotMpl.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTWIDGETS_INSTRUMENTVIEW_MINIPLOTMPL_H
-#define MANTIDQTWIDGETS_INSTRUMENTVIEW_MINIPLOTMPL_H
+#pragma once
 
 #include "MantidQtWidgets/InstrumentView/DllOption.h"
 #include "MantidQtWidgets/MplCpp/Cycler.h"
@@ -79,5 +78,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQTWIDGETS_INSTRUMENTVIEW_MINIPLOTMPL_H
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/MiniPlotQwt.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/MiniPlotQwt.h
index 8fd2afb9f16d6819949f98946e35c2e8943d0248..a0507b94c330afadb54dd8cabbc626612c75115a 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/MiniPlotQwt.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/MiniPlotQwt.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MiniPlotQwt_H_
-#define MiniPlotQwt_H_
+#pragma once
 
 #include <QList>
 #include <QMap>
@@ -91,5 +90,4 @@ private:
 };
 
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif /*MiniPlotQwt_H_*/
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/OpenGLError.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/OpenGLError.h
index 8ead2d104869119ec654516626e9ab92112a2488..ca8183aa02e402168424c6fae4ad780cb20b9ce1 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/OpenGLError.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/OpenGLError.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef OPENGLERROR_H_
-#define OPENGLERROR_H_
+#pragma once
 
 #include <ostream>
 #include <stdexcept>
@@ -30,5 +29,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*OPENGLERROR_H_*/
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/PanelsSurface.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/PanelsSurface.h
index 178160f15dd85d085eceafc0223f6ca0414119da..5993030a3aad305124c0a4bfad54f50710cf5b9d 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/PanelsSurface.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/PanelsSurface.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef PANELSSURFACE_H
-#define PANELSSURFACE_H
+#pragma once
 
 #include "UnwrappedSurface.h"
 
@@ -112,5 +111,3 @@ protected:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // PANELSSURFACE_H
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/PeakMarker2D.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/PeakMarker2D.h
index 1e3ba4c27a0399a41b7289fc2908ff1126179a70..0f19de50c3b0ccedc90672302c91c2fbfd41970d 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/PeakMarker2D.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/PeakMarker2D.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDPLOT_PEAKMARKER2D_H_
-#define MANTIDPLOT_PEAKMARKER2D_H_
+#pragma once
 
 #include "MantidGeometry/Crystal/IPeak.h"
 #include "Shape2D.h"
@@ -86,5 +85,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*MANTIDPLOT_PEAKMARKER2D_H_*/
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/PeakOverlay.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/PeakOverlay.h
index edb5faf473c8e1010a462a5542fcf9a1d9da561c..c1354b46c31ad6fb9e43f8f56dc1b72135203b9b 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/PeakOverlay.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/PeakOverlay.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDPLOT_PEAKOVERLAY_H_
-#define MANTIDPLOT_PEAKOVERLAY_H_
+#pragma once
 
 #include "PeakMarker2D.h"
 #include "Shape2DCollection.h"
@@ -178,5 +177,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*MANTIDPLOT_PEAKOVERLAY_H_*/
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/PlotFitAnalysisPaneModel.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/PlotFitAnalysisPaneModel.h
index 83f3a03a0f3085a8ee1e6aad7c3fb6f41c50860d..5a100d939606fc02a1708167e6e10f2d01588f7e 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/PlotFitAnalysisPaneModel.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/PlotFitAnalysisPaneModel.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_INSTRUMENTVIEW_PLOTFITANALYSISPANEMODEL_H_
-#define MANTIDQT_INSTRUMENTVIEW_PLOTFITANALYSISPANEMODEL_H_
+#pragma once
 
 #include "MantidAPI/IFunction.h"
 
@@ -25,5 +24,3 @@ public:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTIDQT_INSTRUMENTVIEW_PLOTFITANALYSISPANEMODEL_H_ */
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/PlotFitAnalysisPanePresenter.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/PlotFitAnalysisPanePresenter.h
index 58c0d1ae86922f24941db81e6a09b19bcf21e718..abaae12a813b9f8271e3fa5cc012f871bfcc6b2a 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/PlotFitAnalysisPanePresenter.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/PlotFitAnalysisPanePresenter.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_INSTRUMENTVIEW_PLOTFITANALYSISPANEPRESENTER_H_
-#define MANTIDQT_INSTRUMENTVIEW_PLOTFITANALYSISPANEPRESENTER_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidQtWidgets/Common/ObserverPattern.h"
@@ -42,5 +41,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTIDQT_INSTRUMENTVIEW_PLOTFITANALYSISPANEPRESENTER_H_ */
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/PlotFitAnalysisPaneView.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/PlotFitAnalysisPaneView.h
index 24242f33af38302f4b2517e664a4bf04fce60a3a..4c1b6a6d009d5793ef2ecf21d12b2249727e64b7 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/PlotFitAnalysisPaneView.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/PlotFitAnalysisPaneView.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_INSTRUMENTVIEW_PLOTFITPANEVIEW_H_
-#define MANTIDQT_INSTRUMENTVIEW_PLOTFITPANEVIEW_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidQtWidgets/Common/FunctionBrowser.h"
@@ -58,5 +57,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTIDQT_INSTRUMENTVIEW_PLOTFITPANEVIEW_H_ */
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/Projection3D.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/Projection3D.h
index 405b47735ad5ccb82aa79177db60da6f6c7a4813..7547d1b174e6c26e02076f2ff77d98872dfef889 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/Projection3D.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/Projection3D.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef PROJECTION3D_H_
-#define PROJECTION3D_H_
+#pragma once
 
 #include "ProjectionSurface.h"
 #include "Viewport.h"
@@ -86,5 +85,3 @@ protected:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* PROJECTION3D_H_ */
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/ProjectionSurface.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/ProjectionSurface.h
index 971b01bc362ede1514882d22aa20f0834c1cba11..d359cc222d6b1dcff7b567a50d22b4ea9ed031dd 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/ProjectionSurface.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/ProjectionSurface.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef PROJECTIONSURFACE_H
-#define PROJECTIONSURFACE_H
+#pragma once
 
 #include "MantidGeometry/IComponent.h"
 #include "MantidKernel/Quat.h"
@@ -395,5 +394,3 @@ using ProjectionSurface_sptr = boost::shared_ptr<ProjectionSurface>;
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // PROJECTIONSURFACE_H
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/RectF.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/RectF.h
index 9559e6d0b285ac9cc4c6d2043abc917de5f8d379..51872ede0f9e593c4e186437ede74e7a43c09ed7 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/RectF.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/RectF.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef RECTF_H
-#define RECTF_H
+#pragma once
 
 #include <QPoint>
 #include <QRectF>
@@ -208,5 +207,3 @@ inline std::ostream &operator<<(std::ostream &ostr, const QPointF &p) {
 }
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // RECTF_H
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/RotationSurface.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/RotationSurface.h
index 50eff9f1776354920ca1d6591152b5ada766d23e..8834a2878d3a8da80574e3e0836a4d1af61f9a96 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/RotationSurface.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/RotationSurface.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef ROTATIONSURFACE_H
-#define ROTATIONSURFACE_H
+#pragma once
 
 #include "UnwrappedSurface.h"
 
@@ -75,5 +74,3 @@ protected:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // ROTATIONSURFACE_H
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/Shape2D.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/Shape2D.h
index 1d6a72f20ec4649c196593f9cb4f6e318a794fde..7a590c5bc10bad684ba3ae6c305c90de30bdb92e 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/Shape2D.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/Shape2D.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDPLOT_SHAPE2D_H_
-#define MANTIDPLOT_SHAPE2D_H_
+#pragma once
 
 #include "RectF.h"
 
@@ -338,5 +337,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*MANTIDPLOT_SHAPE2D_H_*/
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/Shape2DCollection.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/Shape2DCollection.h
index a7c841eb5ef8dd0b14e9a448154d2d6edc675169..853c7b1519f02d8b5366ee2e0fa72e2dc19669e4 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/Shape2DCollection.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/Shape2DCollection.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDPLOT_SHAPE2DCOLLECTION_H_
-#define MANTIDPLOT_SHAPE2DCOLLECTION_H_
+#pragma once
 
 #include "MantidAPI/ITableWorkspace.h"
 
@@ -164,5 +163,3 @@ protected:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*MANTIDPLOT_SHAPE2DCOLLECTION_H_*/
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/SimpleWidget.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/SimpleWidget.h
index 336858d401707b490eb5ea1a95c83213fe3d6bdc..116bef7db6c53111f8e0d5c3d831d7f0ef94285f 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/SimpleWidget.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/SimpleWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SIMPLEWIDGET_H
-#define SIMPLEWIDGET_H
+#pragma once
 
 #include <QWidget>
 
@@ -50,5 +49,3 @@ protected:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // SIMPLEWIDGET_H
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/UCorrectionDialog.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/UCorrectionDialog.h
index ccdb47c9a6771e459e008bc2e2ed4905ede88674..0aad3b2bfa56a0e5f4753d0abccc41e5aba631d4 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/UCorrectionDialog.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/UCorrectionDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef UCorrectionDIALOG_H
-#define REMOVEERRORSDIALOG_H
+#pragma once
 
 #include <QDialog>
 #include <QPointF>
@@ -32,5 +31,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // REMOVEERRORSDIALOG_H
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/UnwrappedCylinder.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/UnwrappedCylinder.h
index bc2b6297e3b9ad9632833092e3d9f0c024b33bf1..ea3623b38c16b549a2036d3917c7e6df5e0f5d10 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/UnwrappedCylinder.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/UnwrappedCylinder.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef UNWRAPPEDCYLINDER_H
-#define UNWRAPPEDCYLINDER_H
+#pragma once
 
 #include "RotationSurface.h"
 
@@ -29,5 +28,3 @@ protected:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // UNWRAPPEDCYLINDER_H
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/UnwrappedDetector.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/UnwrappedDetector.h
index 2011095f29449ba0e89018aab227e712bdc3602e..74ab6ea0a2caea6d69070a993a755df1aaf0af32 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/UnwrappedDetector.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/UnwrappedDetector.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef UNWRAPPEDDETECTOR_H
-#define UNWRAPPEDDETECTOR_H
+#pragma once
 
 #include "MantidGeometry/IDTypes.h"
 #include "MantidKernel/Quat.h"
@@ -50,5 +49,4 @@ public:
   ///< ComponentInfo/DetectorInfo.
 };
 } // namespace MantidWidgets
-} // namespace MantidQt
-#endif
\ No newline at end of file
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/UnwrappedSphere.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/UnwrappedSphere.h
index 4ee32fb272a1241c766887297309496e5550e757..54c63d1903eeb0e0d101d7537463ab684511d290 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/UnwrappedSphere.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/UnwrappedSphere.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef UNWRAPPEDSPHERE_H
-#define UNWRAPPEDSPHERE_H
+#pragma once
 
 #include "RotationSurface.h"
 
@@ -30,5 +29,3 @@ protected:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // UNWRAPPEDSPHERE_H
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/UnwrappedSurface.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/UnwrappedSurface.h
index 6a3506200643190b2c09c479541c4c1980a0b613..a22dc607c11536f7f1dbfc54ab7d6b4b80ee88b2 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/UnwrappedSurface.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/UnwrappedSurface.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef UNWRAPPEDSURFACE_H
-#define UNWRAPPEDSURFACE_H
+#pragma once
 
 #include "InstrumentActor.h"
 #include "MantidGeometry/Objects/IObject.h"
@@ -178,5 +177,3 @@ protected:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // UNWRAPPEDSURFACE_H
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/Viewport.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/Viewport.h
index 3ada32e41e60809b42ec0e7f1edb331116351829..0126fa2e6ea790fab076fe8f4deba26a26fd803e 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/Viewport.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/Viewport.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef VIEWPORT_H_
-#define VIEWPORT_H_
+#pragma once
 
 #include "MantidKernel/Quat.h"
 #include "MantidKernel/V3D.h"
@@ -183,5 +182,3 @@ protected:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*VIEWPORT_H_*/
diff --git a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/XIntegrationControl.h b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/XIntegrationControl.h
index 83e64734bf4c2bdb9872a6a8f3018c192d12b0f5..5deac1913d62815e37dc4b8fddd6498b45b17a4d 100644
--- a/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/XIntegrationControl.h
+++ b/qt/widgets/instrumentview/inc/MantidQtWidgets/InstrumentView/XIntegrationControl.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef XINTEGRATIONCONTROL_H_
-#define XINTEGRATIONCONTROL_H_
+#pragma once
 
 #include <QFrame>
 #include <QScrollBar>
@@ -92,5 +91,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /*XINTEGRATIONCONTROL_H_*/
diff --git a/qt/widgets/instrumentview/test/InstrumentViewTestInitialization.h b/qt/widgets/instrumentview/test/InstrumentViewTestInitialization.h
index 602399bc07169c648d4e6f739a2df3c769faed1f..6b3e319599400894045022257665d9c7e326cb3c 100644
--- a/qt/widgets/instrumentview/test/InstrumentViewTestInitialization.h
+++ b/qt/widgets/instrumentview/test/InstrumentViewTestInitialization.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_WIDGETS_INSTRUMENTVIEWTESTINITIALIZATION_H
-#define MANTIDQT_WIDGETS_INSTRUMENTVIEWTESTINITIALIZATION_H
+#pragma once
 
 #include "MantidPythonInterface/core/Testing/PythonInterpreterGlobalFixture.h"
 #include "MantidQtWidgets/Common/Testing/QApplicationGlobalFixture.h"
@@ -18,5 +17,3 @@
 //------------------------------------------------------------------------------
 static PythonInterpreterGlobalFixture PYTHON_INTERPRETER;
 static QApplicationGlobalFixture MAIN_QAPPLICATION;
-
-#endif // MANTIDQT_WIDGETS_INSTRUMENTVIEWTESTINITIALIZATION_H
diff --git a/qt/widgets/instrumentview/test/InstrumentWidgetDecoderTest.h b/qt/widgets/instrumentview/test/InstrumentWidgetDecoderTest.h
index 006d58f8c9cb7176d6a3a0ab8b282e6030eb36c8..1cc6492061909c0a584b2c76159273637c81501b 100644
--- a/qt/widgets/instrumentview/test/InstrumentWidgetDecoderTest.h
+++ b/qt/widgets/instrumentview/test/InstrumentWidgetDecoderTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_WIDGETS_INSTRUMENTWIDGETDECODERTEST_H_
-#define MANTIDQT_WIDGETS_INSTRUMENTWIDGETDECODERTEST_H_
+#pragma once
 
 #include "MantidAPI/AlgorithmManager.h"
 #include "MantidAPI/FrameworkManager.h"
@@ -76,5 +75,3 @@ private:
   InstrumentWidgetDecoder *m_decoder;
   QMap<QString, QVariant> m_infoMap;
 };
-
-#endif /* MANTIDQT_WIDGETS_INSTRUMENTWIDGETDECODERTEST_H_ */
\ No newline at end of file
diff --git a/qt/widgets/instrumentview/test/InstrumentWidgetEncoderTest.h b/qt/widgets/instrumentview/test/InstrumentWidgetEncoderTest.h
index e0f2074de08b841544486602fcf197f15339d4d6..384768ff313422de0ef6d3a9c0348fac925b7132 100644
--- a/qt/widgets/instrumentview/test/InstrumentWidgetEncoderTest.h
+++ b/qt/widgets/instrumentview/test/InstrumentWidgetEncoderTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_WIDGETS_INSTRUMENTWIDGETENCODERTEST_H_
-#define MANTIDQT_WIDGETS_INSTRUMENTWIDGETENCODERTEST_H_
+#pragma once
 
 #include "MantidAPI/AlgorithmManager.h"
 #include "MantidAPI/FrameworkManager.h"
@@ -46,5 +45,3 @@ public:
   InstrumentWidget *m_instrumentWidget;
   InstrumentWidgetEncoder *m_encoder;
 };
-
-#endif /* MANTIDQT_WIDGETS_INSTRUMENTWIDGETDECODERTEST_H_ */
diff --git a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Artist.h b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Artist.h
index 214b47c5d2a902eedf03221c56ea23047168f9b2..decbaf849759ef155508d5e22772cbd96b1ca7df 100644
--- a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Artist.h
+++ b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Artist.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_ARTIST_H
-#define MPLCPP_ARTIST_H
+#pragma once
 
 #include "MantidQtWidgets/Common/Python/Object.h"
 #include "MantidQtWidgets/MplCpp/DllConfig.h"
@@ -29,5 +28,3 @@ public:
 } // namespace MplCpp
 } // namespace Widgets
 } // namespace MantidQt
-
-#endif // MPLCPP_ARTIST_H
diff --git a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Axes.h b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Axes.h
index 76868d8636b165dcb5ac0ea77fc16b2026bb2880..ceb4da9d29f7f7cf448edb5d9c2750dbcc85135a 100644
--- a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Axes.h
+++ b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Axes.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_AXES_H
-#define MPLCPP_AXES_H
+#pragma once
 
 #include "MantidQtWidgets/MplCpp/DllConfig.h"
 #include "MantidQtWidgets/MplCpp/Line2D.h"
@@ -66,5 +65,3 @@ public:
 } // namespace MplCpp
 } // namespace Widgets
 } // namespace MantidQt
-
-#endif // MPLCPP_AXES_H
diff --git a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/BackendQt.h b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/BackendQt.h
index eccc9bf72798f7a923489f736ab3e8d6692f3262..e82cc6c9f45ab401404396fc71869fadfc0e3877 100644
--- a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/BackendQt.h
+++ b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/BackendQt.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_BACKENDQT_H
-#define MPLCPP_BACKENDQT_H
+#pragma once
 
 #include "MantidQtWidgets/Common/Python/Object.h"
 #include "MantidQtWidgets/MplCpp/DllConfig.h"
@@ -41,5 +40,3 @@ MANTID_MPLCPP_DLL Common::Python::Object backendModule();
 } // namespace MplCpp
 } // namespace Widgets
 } // namespace MantidQt
-
-#endif // MPLCPP_BACKENDQT_H
diff --git a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/ColorConverter.h b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/ColorConverter.h
index 74382da4fbcc6b9695b830a051fe7baba87aed1e..9a3316fbd2875face2abd36b1237cd8dc69b4142 100644
--- a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/ColorConverter.h
+++ b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/ColorConverter.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_COLORCONVERTER_H
-#define MPLCPP_COLORCONVERTER_H
+#pragma once
 
 #include "MantidQtWidgets/Common/Python/Object.h"
 #include "MantidQtWidgets/MplCpp/DllConfig.h"
@@ -28,5 +27,3 @@ public:
 } // namespace MplCpp
 } // namespace Widgets
 } // namespace MantidQt
-
-#endif // MPLCPP_COLORCONVERTER_H
diff --git a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/ColorbarWidget.h b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/ColorbarWidget.h
index 0b7248e6dc50db39dc82c0bc0d7b5fc3431fbdbe..8fefdc60271557e1447d1aa4d203e8945254c0c3 100644
--- a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/ColorbarWidget.h
+++ b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/ColorbarWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_COLORBARWIDGET_H
-#define MPLCPP_COLORBARWIDGET_H
+#pragma once
 
 #include "MantidQtWidgets/MplCpp/Colors.h"
 #include "MantidQtWidgets/MplCpp/DllConfig.h"
@@ -88,5 +87,3 @@ private: // data
 } // namespace MplCpp
 } // namespace Widgets
 } // namespace MantidQt
-
-#endif // MPLCPP_COLORBARWIDGET_H
diff --git a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Colormap.h b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Colormap.h
index 20c084f1d949ecfcec2af5c44cd69d96fc764a74..bbdbea09a0ba05a5fe7e0f98fa5deb80f9a0bebc 100644
--- a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Colormap.h
+++ b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Colormap.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_COLORMAP_H
-#define MPLCPP_COLORMAP_H
+#pragma once
 
 #include "MantidQtWidgets/MplCpp/DllConfig.h"
 #pragma push_macro("slots")
@@ -42,5 +41,3 @@ MANTID_MPLCPP_DLL QString defaultCMapName();
 } // namespace MplCpp
 } // namespace Widgets
 } // namespace MantidQt
-
-#endif // MPLCPP_COLORMAP_H
diff --git a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Colors.h b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Colors.h
index aacdaf040b1c403ca07566d57d633621084c5a75..447b7994260b2a82826e1888bddc3e1b366bb14a 100644
--- a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Colors.h
+++ b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Colors.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_COLORS_H
-#define MPLCPP_COLORS_H
+#pragma once
 
 #include "MantidQtWidgets/Common/Python/Object.h"
 #include "MantidQtWidgets/MplCpp/DllConfig.h"
@@ -96,5 +95,4 @@ public:
 
 } // namespace MplCpp
 } // namespace Widgets
-} // namespace MantidQt
-#endif // MPLCPP_COLORS_H
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Cycler.h b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Cycler.h
index fa1abe1756186e35c765dd1a2f1685aae0a87248..a4716930d7952981e7372f12dca5b2930ee549f4 100644
--- a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Cycler.h
+++ b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Cycler.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_CYCLER_H
-#define MPLCPP_CYCLER_H
+#pragma once
 
 #include "MantidQtWidgets/MplCpp/DllConfig.h"
 #pragma push_macro("slots")
@@ -37,5 +36,3 @@ MANTID_MPLCPP_DLL Cycler cycler(const char *label, const char *iterable);
 } // namespace MplCpp
 } // namespace Widgets
 } // namespace MantidQt
-
-#endif // MPLCPP_CYCLER_H
diff --git a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/DllConfig.h b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/DllConfig.h
index d1fa98616c61dab8fda8042004089785f61c1670..6b74a5b1aa7771cc4981810e0dfffa91c87e8c96 100644
--- a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/DllConfig.h
+++ b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/DllConfig.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MPLCPP_DLLCONFIG_H_
-#define MANTIDQT_MPLCPP_DLLCONFIG_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 
@@ -14,5 +13,3 @@
 #else
 #define MANTID_MPLCPP_DLL DLLImport
 #endif /* IN_MANTIDQT_MPLCPP */
-
-#endif // MANTIDQT_MPLCPP_DLLCONFIG_H_
diff --git a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/ErrorbarContainer.h b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/ErrorbarContainer.h
index 543205d3cd22a051a8663e4f7028c58067a19bf0..5fbfc15111eca460f98020dda4e08855940f5726 100644
--- a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/ErrorbarContainer.h
+++ b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/ErrorbarContainer.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_ERRORBARCONTAINER_H
-#define MPLCPP_ERRORBARCONTAINER_H
+#pragma once
 
 #include "MantidQtWidgets/Common/Python/Object.h"
 #include "MantidQtWidgets/MplCpp/DllConfig.h"
@@ -23,5 +22,3 @@ public:
 } // namespace MplCpp
 } // namespace Widgets
 } // namespace MantidQt
-
-#endif // MPLCPP_ERRORBARCONTAINER_H
diff --git a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Figure.h b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Figure.h
index 01bb84f684269be95022f599e24dbf4426a53b8c..704783fd356ae72f08d0ab9763ae42efbbcc7709 100644
--- a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Figure.h
+++ b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Figure.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_FIGURE_H
-#define MPLCPP_FIGURE_H
+#pragma once
 
 #include "MantidPythonInterface/core/GlobalInterpreterLock.h"
 #include "MantidQtWidgets/Common/Python/Object.h"
@@ -60,5 +59,3 @@ public:
 } // namespace MplCpp
 } // namespace Widgets
 } // namespace MantidQt
-
-#endif // MPLCPP_FIGURE_H
diff --git a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/FigureCanvasQt.h b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/FigureCanvasQt.h
index fd482a4e02596f9c659cfe638fd8d54822cf596b..1eec4671ce457e91e2f99ce1c34f55f784249369 100644
--- a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/FigureCanvasQt.h
+++ b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/FigureCanvasQt.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_FIGURECANVASQT_H
-#define MPLCPP_FIGURECANVASQT_H
+#pragma once
 
 #include "MantidQtWidgets/MplCpp/DllConfig.h"
 #include "MantidQtWidgets/MplCpp/Figure.h"
@@ -65,5 +64,4 @@ private: // members
 
 } // namespace MplCpp
 } // namespace Widgets
-} // namespace MantidQt
-#endif // MPLCPP_FIGURECANVASQT_H
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Line2D.h b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Line2D.h
index e445d62283993697432cce310346853ed5561309..8a8b292a9e8afa823015bc88cbd38a5fe1d6a678 100644
--- a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Line2D.h
+++ b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Line2D.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_LINE2D_H
-#define MPLCPP_LINE2D_H
+#pragma once
 
 #include "MantidQtWidgets/MplCpp/Artist.h"
 #include "MantidQtWidgets/MplCpp/DllConfig.h"
@@ -54,5 +53,3 @@ private:
 } // namespace MplCpp
 } // namespace Widgets
 } // namespace MantidQt
-
-#endif // MPLCPP_LINE2D_H
diff --git a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/MantidAxes.h b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/MantidAxes.h
index b8fe6481941fde78c67a7c7b86e28616576914db..0b36514063a88d0e7acfbdb2c89ca43000cee912 100644
--- a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/MantidAxes.h
+++ b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/MantidAxes.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_MANTID_AXES_H
-#define MPLCPP_MANTID_AXES_H
+#pragma once
 
 #include "MantidAPI/MatrixWorkspace_fwd.h"
 #include "MantidQtWidgets/MplCpp/Axes.h"
@@ -55,5 +54,3 @@ public:
 } // namespace MplCpp
 } // namespace Widgets
 } // namespace MantidQt
-
-#endif // MPLCPP_AXES_H
diff --git a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/MantidColorMap.h b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/MantidColorMap.h
index 053a89148668b6a2052396b91c1aee529b618c5c..aee15437c9638baa67559b45b39f2cc4828611f0 100644
--- a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/MantidColorMap.h
+++ b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/MantidColorMap.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_MANTIDCOLORMAP_H
-#define MPLCPP_MANTIDCOLORMAP_H
+#pragma once
 
 #include "MantidQtWidgets/MplCpp/DllConfig.h"
 #include "MantidQtWidgets/MplCpp/ScalarMappable.h"
@@ -57,5 +56,3 @@ private:
 } // namespace MplCpp
 } // namespace Widgets
 } // namespace MantidQt
-
-#endif // MPLCPP_MANTIDCOLORMAP_H
diff --git a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/PanZoomTool.h b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/PanZoomTool.h
index 46e1a9c6ac9d4f2fba9cdceff640e988f9253904..65e0d2c3b0ca5e2718f9729e9c665fb9beb2447d 100644
--- a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/PanZoomTool.h
+++ b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/PanZoomTool.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_PANZOOMTOOL_H
-#define MPLCPP_PANZOOMTOOL_H
+#pragma once
 
 #include "MantidQtWidgets/Common/Python/Object.h"
 #include "MantidQtWidgets/MplCpp/DllConfig.h"
@@ -46,5 +45,3 @@ private:
 } // namespace MplCpp
 } // namespace Widgets
 } // namespace MantidQt
-
-#endif // MPLCPP_PANZOOMTOOL_H
diff --git a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/PeakMarker.h b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/PeakMarker.h
index 4ee64f71074478a69f9e4f2e27715634cba2b3a8..c0492d82a01daa250fae911d143bd01952c3ec31 100644
--- a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/PeakMarker.h
+++ b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/PeakMarker.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_PEAKMARKER_H
-#define MPLCPP_PEAKMARKER_H
+#pragma once
 
 #include "MantidQtWidgets/Common/Python/Object.h"
 #include "MantidQtWidgets/MplCpp/DllConfig.h"
@@ -47,5 +46,3 @@ public:
 } // namespace MplCpp
 } // namespace Widgets
 } // namespace MantidQt
-
-#endif // MPLCPP_PEAKMARKER_H
diff --git a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Plot.h b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Plot.h
index d84c9a5cbf906b622e8caa2b620f2e105f89c6e9..61263fa5f7a34b35d34a0217b04e792d8dbea457 100644
--- a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Plot.h
+++ b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/Plot.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_PLOT_H
-#define MPLCPP_PLOT_H
+#pragma once
 
 #include "MantidQtWidgets/Common/Python/Object.h"
 #include "MantidQtWidgets/MplCpp/DllConfig.h"
@@ -152,5 +151,3 @@ pcolormesh(const QStringList &workspaces,
 } // namespace MplCpp
 } // namespace Widgets
 } // namespace MantidQt
-
-#endif // MPLCPP_PLOT_H
diff --git a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/RangeMarker.h b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/RangeMarker.h
index 1cfd535549764a71bed08c7d19149cc4abe68186..f8be1a546652f7bcd031db63007d8aefd062955a 100644
--- a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/RangeMarker.h
+++ b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/RangeMarker.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_RANGEMARKER_H
-#define MPLCPP_RANGEMARKER_H
+#pragma once
 
 #include "MantidQtWidgets/Common/Python/Object.h"
 #include "MantidQtWidgets/MplCpp/DllConfig.h"
@@ -55,5 +54,3 @@ public:
 } // namespace MplCpp
 } // namespace Widgets
 } // namespace MantidQt
-
-#endif // MPLCPP_RANGEMARKER_H
diff --git a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/ScalarMappable.h b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/ScalarMappable.h
index 5e0e1f8d6cb97c592543c18558fa10c0de5fae5a..18d2e56c84bbec532076a795a04a7f89b02b45ab 100644
--- a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/ScalarMappable.h
+++ b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/ScalarMappable.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_SCALARMAPPABLE_H
-#define MPLCPP_SCALARMAPPABLE_H
+#pragma once
 
 #include "MantidQtWidgets/MplCpp/Colormap.h"
 #include "MantidQtWidgets/MplCpp/Colors.h"
@@ -45,5 +44,3 @@ public:
 } // namespace MplCpp
 } // namespace Widgets
 } // namespace MantidQt
-
-#endif // MPLCPP_SCALARMAPPABLE_H
diff --git a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/SingleMarker.h b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/SingleMarker.h
index b5d2f0de860b9f0bcc2174f6917355d24687f218..6c1cc0dbf585315167864373b71c4ae8dab5307c 100644
--- a/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/SingleMarker.h
+++ b/qt/widgets/mplcpp/inc/MantidQtWidgets/MplCpp/SingleMarker.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_SINGLEMARKER_H
-#define MPLCPP_SINGLEMARKER_H
+#pragma once
 
 #include "MantidQtWidgets/Common/Python/Object.h"
 #include "MantidQtWidgets/MplCpp/DllConfig.h"
@@ -49,5 +48,3 @@ public:
 } // namespace MplCpp
 } // namespace Widgets
 } // namespace MantidQt
-
-#endif // MPLCPP_SINGLEMARKER_H
diff --git a/qt/widgets/mplcpp/test/ArtistTest.h b/qt/widgets/mplcpp/test/ArtistTest.h
index 314a715e285f97e1a61a8ffb501130a562373414..757ca092b8d4cd024b8fa77d34f025951ebc9fc6 100644
--- a/qt/widgets/mplcpp/test/ArtistTest.h
+++ b/qt/widgets/mplcpp/test/ArtistTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_ARTISTTEST_H
-#define MPLCPP_ARTISTTEST_H
+#pragma once
 
 #include "MantidQtWidgets/MplCpp/Artist.h"
 
@@ -51,5 +50,3 @@ public:
     TS_ASSERT_THROWS(Artist artist(none), const std::invalid_argument &);
   }
 };
-
-#endif // ARTISTTEST_H
diff --git a/qt/widgets/mplcpp/test/AxesTest.h b/qt/widgets/mplcpp/test/AxesTest.h
index dd6bcdef97cd55d1e0ac6511877a47b307b0ad39..0960bdeba85f1c74164d6f095f20952dfc6e16d2 100644
--- a/qt/widgets/mplcpp/test/AxesTest.h
+++ b/qt/widgets/mplcpp/test/AxesTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_AXESTEST_H
-#define MPLCPP_AXESTEST_H
+#pragma once
 
 #include "MantidQtWidgets/MplCpp/Axes.h"
 #include <cxxtest/TestSuite.h>
@@ -189,5 +188,3 @@ private:
     return axesModule.attr("Axes")(figure, rect);
   }
 };
-
-#endif // MPLCPP_AXESTEST_H
diff --git a/qt/widgets/mplcpp/test/ColorConverterTest.h b/qt/widgets/mplcpp/test/ColorConverterTest.h
index 4a7593673d77eb7aa8e3ecce6f4b4867dc8cdf13..b4d02faca1aed7b6f6ef3e35eb0eb176b7eba6b8 100644
--- a/qt/widgets/mplcpp/test/ColorConverterTest.h
+++ b/qt/widgets/mplcpp/test/ColorConverterTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_COLORCONVERTERTEST_H
-#define MPLCPP_COLORCONVERTERTEST_H
+#pragma once
 
 #include "MantidQtWidgets/MplCpp/ColorConverter.h"
 #include <QRgb>
@@ -29,5 +28,3 @@ public:
     TS_ASSERT_EQUALS(191, color.green());
   }
 };
-
-#endif // MPLCPP_COLORCONVERTERTEST_H
diff --git a/qt/widgets/mplcpp/test/ColormapTest.h b/qt/widgets/mplcpp/test/ColormapTest.h
index da4d7a785e1726dc3d35b7fc58f0f57508fc8e83..86ca9a26f5929dcf8c2383f7fa4aa2672c8a2a7f 100644
--- a/qt/widgets/mplcpp/test/ColormapTest.h
+++ b/qt/widgets/mplcpp/test/ColormapTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_COLORMAPTEST_H
-#define MPLCPP_COLORMAPTEST_H
+#pragma once
 
 #include "MantidPythonInterface/core/ErrorHandling.h"
 #include "MantidQtWidgets/MplCpp/Colormap.h"
@@ -49,5 +48,3 @@ public:
                      const std::invalid_argument &);
   }
 };
-
-#endif // MPLCPP_COLORMAPTEST_H
diff --git a/qt/widgets/mplcpp/test/ColorsTest.h b/qt/widgets/mplcpp/test/ColorsTest.h
index f6024bd9a4c3371f735ac42d0d0cb21085e36e44..660bca18778edb47bffce2e92d7caa9987245c28 100644
--- a/qt/widgets/mplcpp/test/ColorsTest.h
+++ b/qt/widgets/mplcpp/test/ColorsTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_COLORSTEST_H
-#define MPLCPP_COLORSTEST_H
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -80,5 +79,3 @@ private:
     TS_ASSERT_EQUALS(vmax, norm.pyobj().attr("vmax"));
   }
 };
-
-#endif // MPLCPP_COLORSTEST_H
diff --git a/qt/widgets/mplcpp/test/CyclerTest.h b/qt/widgets/mplcpp/test/CyclerTest.h
index 038b31b0667e6f64ba9b37decce0070cc0826c86..1ba5d1985b6f8a62792d6e3f1720c0a49b81fa25 100644
--- a/qt/widgets/mplcpp/test/CyclerTest.h
+++ b/qt/widgets/mplcpp/test/CyclerTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPPTEST_CYCLERTEST_H
-#define MPLCPPTEST_CYCLERTEST_H
+#pragma once
 
 #include "MantidQtWidgets/MplCpp/Cycler.h"
 
@@ -41,5 +40,3 @@ public:
     TS_ASSERT_THROWS(Cycler cycler(none), const std::invalid_argument &);
   }
 };
-
-#endif // MPLCPPTEST_CYCLERTEST_H
diff --git a/qt/widgets/mplcpp/test/FigureCanvasQtTest.h b/qt/widgets/mplcpp/test/FigureCanvasQtTest.h
index 8ac7a89639291826f3166dd68b59145408d7d508..e87eef7df0545f0a9ac30aca8c6d9737ca5e6b05 100644
--- a/qt/widgets/mplcpp/test/FigureCanvasQtTest.h
+++ b/qt/widgets/mplcpp/test/FigureCanvasQtTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_FIGURECANVASQTTEST_H
-#define MPLCPP_FIGURECANVASQTTEST_H
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -62,5 +61,3 @@ public:
       TS_ASSERT_EQUALS(true, legend.pyobj().attr("get_draggable")());
   }
 };
-
-#endif // MPLCPP_FIGURECANVASQTTEST_H
diff --git a/qt/widgets/mplcpp/test/FigureTest.h b/qt/widgets/mplcpp/test/FigureTest.h
index c115bcf89ad38bd36d673a0ecdbd8a260f09fa87..24e373c74292c5d51072d68d4bcc23dc81986bda 100644
--- a/qt/widgets/mplcpp/test/FigureTest.h
+++ b/qt/widgets/mplcpp/test/FigureTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_FIGURETEST_H
-#define MPLCPP_FIGURETEST_H
+#pragma once
 
 #include "MantidQtWidgets/MplCpp/Figure.h"
 #include "MantidQtWidgets/MplCpp/ScalarMappable.h"
@@ -87,5 +86,3 @@ public:
                      const std::invalid_argument &);
   }
 };
-
-#endif // FigureTEST_H
diff --git a/qt/widgets/mplcpp/test/Line2DTest.h b/qt/widgets/mplcpp/test/Line2DTest.h
index d3c959ebf4248b01e4ae1099db1f5cf4cd1b48c0..bf70cc3f1f5827ce10dbf1f2654c24d55dab8b0f 100644
--- a/qt/widgets/mplcpp/test/Line2DTest.h
+++ b/qt/widgets/mplcpp/test/Line2DTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_LINE2DTEST_H
-#define MPLCPP_LINE2DTEST_H
+#pragma once
 
 #include "MantidQtWidgets/MplCpp/Line2D.h"
 #include <QRgb>
@@ -93,5 +92,3 @@ private:
     return linesModule.attr("Line2D")(data, data);
   }
 };
-
-#endif // MPLCPP_LINE2DTEST_H
diff --git a/qt/widgets/mplcpp/test/MantidAxesTest.h b/qt/widgets/mplcpp/test/MantidAxesTest.h
index 46cb4b71f9fb3fb17429ebe1ccbcdcc7710cf15f..39fac35f9e715088dd6ca01de129f372e42f2170 100644
--- a/qt/widgets/mplcpp/test/MantidAxesTest.h
+++ b/qt/widgets/mplcpp/test/MantidAxesTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_MANTIDAXESTEST_H
-#define MPLCPP_MANTIDAXESTEST_H
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidDataObjects/Workspace2D.h"
@@ -112,5 +111,3 @@ private:
     return ws;
   }
 };
-
-#endif // MPLCPP_MANTIDAXESTEST_H
diff --git a/qt/widgets/mplcpp/test/MantidColormapTest.h b/qt/widgets/mplcpp/test/MantidColormapTest.h
index 7ab4d02b2c729b04eb4366e0ec8293476d3cdd1a..de56fbba3759a0c153516c2b034f1ce322920b6b 100644
--- a/qt/widgets/mplcpp/test/MantidColormapTest.h
+++ b/qt/widgets/mplcpp/test/MantidColormapTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDCOLORMAPTEST_H
-#define MANTIDCOLORMAPTEST_H
+#pragma once
 
 #include "MantidQtWidgets/MplCpp/MantidColorMap.h"
 
@@ -32,5 +31,3 @@ public:
                      const PythonException &);
   }
 };
-
-#endif // MANTIDCOLORMAPTEST_H
diff --git a/qt/widgets/mplcpp/test/MplCppTestInitialization.h b/qt/widgets/mplcpp/test/MplCppTestInitialization.h
index 29c7d16ddb09ac436c8adfc553faff56e658183e..b35f4d9f141e696f9e0196ad277c0ab66859d105 100644
--- a/qt/widgets/mplcpp/test/MplCppTestInitialization.h
+++ b/qt/widgets/mplcpp/test/MplCppTestInitialization.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPPTESTGLOBALINITIALIZATION_H
-#define MPLCPPTESTGLOBALINITIALIZATION_H
+#pragma once
 
 #include "MantidPythonInterface/core/Testing/PythonInterpreterGlobalFixture.h"
 #include "MantidQtWidgets/Common/Testing/QApplicationGlobalFixture.h"
@@ -18,5 +17,3 @@
 //------------------------------------------------------------------------------
 static PythonInterpreterGlobalFixture PYTHON_INTERPRETER;
 static QApplicationGlobalFixture MAIN_QAPPLICATION;
-
-#endif // MPLCPPTESTGLOBALINITIALIZATION_H
diff --git a/qt/widgets/mplcpp/test/PanZoomToolTest.h b/qt/widgets/mplcpp/test/PanZoomToolTest.h
index b3431837cca3120f3f8a3d4e68e6942eb2e58789..8d45683590b98278c5ab0d43f47bc9f58b7f6ac7 100644
--- a/qt/widgets/mplcpp/test/PanZoomToolTest.h
+++ b/qt/widgets/mplcpp/test/PanZoomToolTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_PANPanpanZoomToolTest_H
-#define MPLCPP_PANPanpanZoomToolTest_H
+#pragma once
 
 #include "MantidQtWidgets/MplCpp/FigureCanvasQt.h"
 #include "MantidQtWidgets/MplCpp/PanZoomTool.h"
@@ -105,5 +104,3 @@ private:
     }
   }
 };
-
-#endif // MPLCPP_PanpanZoomToolTest_H
diff --git a/qt/widgets/mplcpp/test/PlotTest.h b/qt/widgets/mplcpp/test/PlotTest.h
index d09c6c6cf698a7582f84679b7d886269204cedf4..2387c91fd026025f0c27217759fcd8af55e00de9 100644
--- a/qt/widgets/mplcpp/test/PlotTest.h
+++ b/qt/widgets/mplcpp/test/PlotTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_PLOTTEST_H
-#define MPLCPP_PLOTTEST_H
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -167,5 +166,3 @@ private:
 
   constexpr static auto m_testws_name = "ws";
 };
-
-#endif // MPLCPP_PLOTTEST_H
diff --git a/qt/widgets/mplcpp/test/QBackendExtractTest.h b/qt/widgets/mplcpp/test/QBackendExtractTest.h
index 3e2944a53887e8673c1bb782afbe96e39218be91..3a89d6f6edfea4e40376f08a5b527826c73bb788 100644
--- a/qt/widgets/mplcpp/test/QBackendExtractTest.h
+++ b/qt/widgets/mplcpp/test/QBackendExtractTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_QBACKENDEXTRACTTEST_H
-#define MPLCPP_QBACKENDEXTRACTTEST_H
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -45,5 +44,3 @@ public:
                      const std::runtime_error &);
   }
 };
-
-#endif // MPLCPP_QBACKENDEXTRACTTEST_H
diff --git a/qt/widgets/mplcpp/test/ScalarMappableTest.h b/qt/widgets/mplcpp/test/ScalarMappableTest.h
index 0a177a84349a861fe133a1263612669c05c78deb..69caae638aaf017f23e012245466b734da92fa49 100644
--- a/qt/widgets/mplcpp/test/ScalarMappableTest.h
+++ b/qt/widgets/mplcpp/test/ScalarMappableTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MPLCPP_SCALARMAPPABLETEST_H
-#define MPLCPP_SCALARMAPPABLETEST_H
+#pragma once
 
 #include "MantidQtWidgets/MplCpp/Colormap.h"
 #include "MantidQtWidgets/MplCpp/Colors.h"
@@ -146,5 +145,3 @@ public:
     TS_ASSERT_EQUALS(static_cast<int>(alpha * 255), qAlpha(rgba[1]));
   }
 };
-
-#endif // MPLCPP_SCALARMAPPABLETEST_H
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/AxisID.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/AxisID.h
index 834bc001dfe10645cc9f5dbc6efde21c49d2f31d..219ae6a217c33deee8630beac9472465efa896e1 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/AxisID.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/AxisID.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_PLOTTING_AXIS_H_
-#define MANTIDQT_PLOTTING_AXIS_H_
+#pragma once
 
 namespace MantidQt {
 namespace MantidWidgets {
@@ -25,5 +24,3 @@ inline constexpr int toQwtAxis(const AxisID id) { return static_cast<int>(id); }
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQT_PLOTTING_AXIS_H_
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/ContourPreviewPlot.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/ContourPreviewPlot.h
index 9c4bcb3c7679ae33bb3af4cedb4d9f8673ff2ea9..9426eaf4cc779cd0641ad7a3a4a3d7190a6e391c 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/ContourPreviewPlot.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/ContourPreviewPlot.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_CONTOURPREVIEWPLOT_H_
-#define MANTIDQTMANTIDWIDGETS_CONTOURPREVIEWPLOT_H_
+#pragma once
 
 #include <QtGlobal>
 
@@ -14,5 +13,3 @@
 #else
 #include "MantidQtWidgets/Plotting/Mpl/ContourPreviewPlot.h"
 #endif
-
-#endif // MANTIDQTMANTIDWIDGETS_CONTOURPREVIEWPLOT_H_
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/DllOption.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/DllOption.h
index 43e4f07d85104bb605021195976bbe24116ee3fb..85dc7ac45eab1825839f1d6c9693b8a5df46d93c 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/DllOption.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/DllOption.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_PLOTTING_DLLOPTION_H_
-#define MANTIDQT_PLOTTING_DLLOPTION_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 
@@ -16,5 +15,3 @@
 #define EXPORT_OPT_MANTIDQT_PLOTTING DLLImport
 #define EXTERN_MANTIDQT_PLOTTING extern
 #endif /* IN_MANTIDQT_PLOTTING */
-
-#endif // MANTIDQT_PLOTTING_DLLOPTION_H_
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Mpl/ContourPreviewPlot.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Mpl/ContourPreviewPlot.h
index 82813fe6346c1dcaa3fb07498431fb08f6e95ff6..7454b4019ac4e061fe1b1e827aa8353768fab51c 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Mpl/ContourPreviewPlot.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Mpl/ContourPreviewPlot.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_PLOTTING_MPL_CONTOURPREVIEWPLOT_H_
-#define MANTIDQT_PLOTTING_MPL_CONTOURPREVIEWPLOT_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/MatrixWorkspace.h"
@@ -65,5 +64,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTIDQT_PLOTTING_MPL_CONTOURPREVIEWPLOT_H_ */
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Mpl/PeakPicker.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Mpl/PeakPicker.h
index 59f25db840f27d39340a88e05cac76a5c92bb4b2..5584303281334b5e04942de8d00df51c5f003601 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Mpl/PeakPicker.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Mpl/PeakPicker.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_PLOTTING_MPL_PEAKPICKER_H_
-#define MANTIDQT_PLOTTING_MPL_PEAKPICKER_H_
+#pragma once
 
 #include "MantidAPI/IPeakFunction.h"
 #include "MantidQtWidgets/MplCpp/PeakMarker.h"
@@ -55,5 +54,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQT_PLOTTING_MPL_PEAKPICKER_H_
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Mpl/PreviewPlot.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Mpl/PreviewPlot.h
index bb7a82ca2ff2d5c60e058801a7dad6fe488fa240..c8f57203d1e0652b65f7b9429c585812187ca47f 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Mpl/PreviewPlot.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Mpl/PreviewPlot.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_PLOTTING_MPL_PREVIEWPLOT_H_
-#define MANTIDQT_PLOTTING_MPL_PREVIEWPLOT_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidAPI/MatrixWorkspace_fwd.h"
@@ -175,5 +174,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQT_PLOTTING_MPL_PREVIEWPLOT_H_
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Mpl/RangeSelector.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Mpl/RangeSelector.h
index ff1634af3458084d7b6fd1fd1cf62b063826dc99..81a841f7f24eb88941c98ddd93490fef801fabdd 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Mpl/RangeSelector.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Mpl/RangeSelector.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_PLOTTING_MPL_RANGESELECTOR_H_
-#define MANTIDQT_PLOTTING_MPL_RANGESELECTOR_H_
+#pragma once
 
 #include "MantidQtWidgets/MplCpp/RangeMarker.h"
 #include "MantidQtWidgets/Plotting/DllOption.h"
@@ -76,5 +75,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQT_PLOTTING_MPL_RANGESELECTOR_H_
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Mpl/SingleSelector.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Mpl/SingleSelector.h
index d01e9c3b1060c8fec081eac532dcaa1bb21213a7..c34af9659b27992bbba513503baa2e537d8c1068 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Mpl/SingleSelector.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Mpl/SingleSelector.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_PLOTTING_MPL_SINGLESELECTOR_H_
-#define MANTIDQT_PLOTTING_MPL_SINGLESELECTOR_H_
+#pragma once
 
 #include "MantidQtWidgets/MplCpp/SingleMarker.h"
 #include "MantidQtWidgets/Plotting/DllOption.h"
@@ -73,5 +72,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQT_PLOTTING_MPL_SINGLESELECTOR_H_
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/PeakPicker.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/PeakPicker.h
index b7a138fb386098329163489405c3ee9c0aed1f45..eb2bc6d725b413361cc5c504f6dd3fb3bd34fcde 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/PeakPicker.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/PeakPicker.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGET_PEAKPICKER_H
-#define MANTIDQT_MANTIDWIDGET_PEAKPICKER_H
+#pragma once
 
 #include <QtGlobal>
 
@@ -14,5 +13,3 @@
 #else
 #include "MantidQtWidgets/Plotting/Mpl/PeakPicker.h"
 #endif
-
-#endif // MANTIDQT_MANTIDWIDGET_PEAKPICKER_H
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/PreviewPlot.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/PreviewPlot.h
index 940ce0ab36ba8e8673364a39843f8301c6933028..ccba687a296cef2598f2104035af8b1c1fc8a8b3 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/PreviewPlot.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/PreviewPlot.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_PREVIEWPLOT_H_
-#define MANTIDQTMANTIDWIDGETS_PREVIEWPLOT_H_
+#pragma once
 
 #include <QtGlobal>
 
@@ -14,5 +13,3 @@
 #else
 #include "MantidQtWidgets/Plotting/Mpl/PreviewPlot.h"
 #endif
-
-#endif // MANTIDQTMANTIDWIDGETS_PREVIEWPLOT_H_
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/ColorBarWidget.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/ColorBarWidget.h
index e5e7da1e22766755bc1cbc442d76d3d00860e2d7..4c53f05d6f2f81a941a36000924755b359c85de7 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/ColorBarWidget.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/ColorBarWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_COLORBARWIDGET_H_
-#define MANTID_MANTIDWIDGETS_COLORBARWIDGET_H_
+#pragma once
 
 #include "MantidQtWidgets/Plotting/DllOption.h"
 #include "MantidQtWidgets/Plotting/Qwt/MantidColorMap.h"
@@ -154,5 +153,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTID_MANTIDWIDGETS_COLORBARWIDGET_H_
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/ContourPreviewPlot.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/ContourPreviewPlot.h
index 75ebdf22467dbfad076993200ac49d8767c49d2e..94509866de632cfbf01907cb3cd0b224340f0fca 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/ContourPreviewPlot.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/ContourPreviewPlot.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_CONTOURPREVIEWPLOT_H_
-#define MANTID_MANTIDWIDGETS_CONTOURPREVIEWPLOT_H_
+#pragma once
 
 #include "ui_ContourPreviewPlot.h"
 
@@ -110,5 +109,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTID_MANTIDWIDGETS_CONTOURPREVIEWPLOT_H_ */
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/DisplayCurveFit.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/DisplayCurveFit.h
index a36dd4000e2bd23fe27ecab0362b4a3c9389bed9..03805e942614694d87743f5cf1ed529f508a5f9c 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/DisplayCurveFit.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/DisplayCurveFit.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_DISPLAYCURVEFIT_H_
-#define MANTID_MANTIDWIDGETS_DISPLAYCURVEFIT_H_
+#pragma once
 
 #include "MantidAPI/MatrixWorkspace.h"
 #include "MantidQtWidgets/Common/MantidWidget.h"
@@ -88,5 +87,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTID_MANTIDWIDGETS_DISPLAYCURVEFIT_H_
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/DraggableColorBarWidget.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/DraggableColorBarWidget.h
index f5d99aeb90440ec950f9771dce11e0420df56675..0071f9714344516430bd95ad2fc92daecf705eb9 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/DraggableColorBarWidget.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/DraggableColorBarWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DRAGGABLECOLORBARWIDGET_H_
-#define DRAGGABLECOLORBARWIDGET_H_
+#pragma once
 
 #include "MantidQtWidgets/Plotting/DllOption.h"
 #include <QFrame>
@@ -84,5 +83,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // DRAGGABLECOLORBARWIDGET_H_
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/ErrorCurve.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/ErrorCurve.h
index 737b50215a27f576706e37f08936e88476d9b830..1964833cb80fa45820e5f3d1e66b34f61c5a7d38 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/ErrorCurve.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/ErrorCurve.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDWIDGETS_ERRORCURVE_H
-#define MANTIDWIDGETS_ERRORCURVE_H
+#pragma once
 
 #include "MantidQtWidgets/Plotting/DllOption.h"
 #include <qwt_plot_curve.h>
@@ -38,5 +37,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTIDWIDGETS_ERRORCURVE_H */
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/MWView.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/MWView.h
index 84ba598336cec341812274487459f5933d6ad49a..dcefd8aec6a2c0d0da0126e21ccaa99f90c17354 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/MWView.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/MWView.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_MWVIEW_H_
-#define MANTID_MANTIDWIDGETS_MWVIEW_H_
+#pragma once
 
 // includes for interface development
 #include "MantidQtWidgets/Common/MdSettings.h"
@@ -108,5 +107,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTID_MANTIDWIDGETS_MWVIEW_H_ */
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/MantidColorMap.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/MantidColorMap.h
index f5390632702132714b165d6cd16a3effb9ef98f6..a6c58e99fe5e004912232fc29f006d9b82e3e769 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/MantidColorMap.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/MantidColorMap.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDCOLORMAP_H_
-#define MANTIDCOLORMAP_H_
+#pragma once
 
 //---------------------------------------------
 // Includes
@@ -120,5 +119,3 @@ private:
 
   double m_nth_power;
 };
-
-#endif // MANTIDCOLORMAP_H_
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/MantidQwtIMDWorkspaceData.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/MantidQwtIMDWorkspaceData.h
index da531a52ea2caf78e8819f7e819fc5e6bcd114ad..2399278fbbc7385d5318f76e85bab5b71431aca4 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/MantidQwtIMDWorkspaceData.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/MantidQwtIMDWorkspaceData.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTAPI_MANTIDQWTIMDWORKSPACEDATA_H
-#define MANTIDQTAPI_MANTIDQWTIMDWORKSPACEDATA_H
+#pragma once
 
 #include "MantidAPI/IMDWorkspace.h"
 #include "MantidKernel/VMD.h"
@@ -115,5 +114,4 @@ private:
   /// This will correspond to -1 (distance)
   /// or the index into the original workspace dimensions
   int m_currentPlotAxis;
-};
-#endif
+};
\ No newline at end of file
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/MantidQwtWorkspaceData.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/MantidQwtWorkspaceData.h
index 19e6c8c61e06b6e3087bbd3cd55639874415b94a..d37bb8b9f18e4591528092d90c05da512fb15551 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/MantidQwtWorkspaceData.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/MantidQwtWorkspaceData.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTAPI_MANTIDQWTWORKSPACEDATA_H
-#define MANTIDQTAPI_MANTIDQWTWORKSPACEDATA_H
+#pragma once
 
 #include "MantidQtWidgets/Plotting/DllOption.h"
 #include "qwt_data.h"
@@ -95,5 +94,3 @@ public:
   virtual MantidQwtMatrixWorkspaceData *
   copyWithNewSource(const Mantid::API::MatrixWorkspace &workspace) const = 0;
 };
-
-#endif
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/PeakPicker.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/PeakPicker.h
index abef919ee420dec58665d008b38723ec76ddc26f..41d32daa9ec033426402e2be384b35718c79826c 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/PeakPicker.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/PeakPicker.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGETS_PEAKPICKER_H_
-#define MANTIDQT_MANTIDWIDGETS_PEAKPICKER_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 
@@ -77,5 +76,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTIDQT_MANTIDWIDGETS_PEAKPICKER_H_ */
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/PowerScaleEngine.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/PowerScaleEngine.h
index 52eaf4538b493d8bb08589670dd9c3bebb91c1d9..b38e5def03a3836eac5dbcd908bfcf3f1aca1171 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/PowerScaleEngine.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/PowerScaleEngine.h
@@ -27,8 +27,7 @@
  *                                                                         *
  ***************************************************************************/
 
-#ifndef POWER_SCALE_ENGINE_H
-#define POWER_SCALE_ENGINE_H
+#pragma once
 
 #include "MantidQtWidgets/Plotting/DllOption.h"
 #include "ScaleEngine.h"
@@ -84,5 +83,3 @@ private:
   QwtValueList buildMajorTicks(const QwtDoubleInterval &interval,
                                double stepSize) const;
 };
-
-#endif
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/PreviewPlot.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/PreviewPlot.h
index b32259ce1e005b68d4d93c5fe488ea9a5a77b545..e34637ed0fd217b5f3f8f94ef400003e04e12cd0 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/PreviewPlot.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/PreviewPlot.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTMANTIDWIDGETS_QWT_PREVIEWPLOT_H_
-#define MANTIDQTMANTIDWIDGETS_QWT_PREVIEWPLOT_H_
+#pragma once
 
 #include "ui_PreviewPlot.h"
 
@@ -227,5 +226,3 @@ private:
 };
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif // MANTIDQTMANTIDWIDGETS_QWT_PREVIEWPLOT_H_
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/QwtHelper.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/QwtHelper.h
index 02ba028bc8347c6f1ae1dcb12b1d4427f4f7d0b1..c82af9b02df790265ccbbc186ff37a1b88d34e82 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/QwtHelper.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/QwtHelper.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_API_QWTHELPER_H_
-#define MANTID_API_QWTHELPER_H_
+#pragma once
 
 #include "MantidAPI/IFunction.h"
 #include "MantidAPI/MatrixWorkspace_fwd.h"
@@ -46,5 +45,3 @@ EXPORT_OPT_MANTIDQT_PLOTTING boost::shared_ptr<QwtData> emptyCurveData();
 } // namespace QwtHelper
 } // namespace API
 } // namespace MantidQt
-
-#endif /* MANTID_API_QWTHELPER_H_ */
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/QwtRasterDataMD.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/QwtRasterDataMD.h
index 9de029cd60ebeb6373743d1b6998762e11c4a8cf..a31059b3a785634d16402450b17b3bd8b06c25f2 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/QwtRasterDataMD.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/QwtRasterDataMD.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef QwtRasterDataMD_H_
-#define QwtRasterDataMD_H_
+#pragma once
 
 #include "MantidAPI/IMDWorkspace.h"
 #include "MantidAPI/MatrixWorkspace_fwd.h"
@@ -124,5 +123,3 @@ protected:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif /* QwtRasterDataMD_H_ */
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/QwtRasterDataMDNonOrthogonal.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/QwtRasterDataMDNonOrthogonal.h
index be278292905ad044bffa93b498548f5b261f6bef..175c9dc8893b80dbb52556b3b4c97b3ade3860d4 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/QwtRasterDataMDNonOrthogonal.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/QwtRasterDataMDNonOrthogonal.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef QwtRasterDataMDNonOrthogonal_H_
-#define QwtRasterDataMDNonOrthogonal_H_
+#pragma once
 
 #include "MantidAPI/IMDWorkspace.h"
 #include "MantidKernel/Matrix.h"
@@ -41,5 +40,3 @@ protected:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif /* QwtRasterDataMDNonOrthogonal_H_ */
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/QwtWorkspaceBinData.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/QwtWorkspaceBinData.h
index d8e39c4af4db38fe7009aa682f22b29d27a66e12..3245b7f585b087844911b20a54a95d8ea5cc038d 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/QwtWorkspaceBinData.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/QwtWorkspaceBinData.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTAPI_QWTWORKSPACEBINDATA_H
-#define MANTIDQTAPI_QWTWORKSPACEBINDATA_H
+#pragma once
 
 #include "MantidAPI/MatrixWorkspace_fwd.h"
 #include "MantidKernel/cow_ptr.h"
@@ -79,5 +78,4 @@ private:
   QString m_xTitle;
   /// A title for the Y axis
   QString m_yTitle;
-};
-#endif
+};
\ No newline at end of file
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/QwtWorkspaceSpectrumData.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/QwtWorkspaceSpectrumData.h
index 139e92f6e564d194455ce4aeeceadc22ff33c61a..285698743b92219e348fa41379508b6535af951a 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/QwtWorkspaceSpectrumData.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/QwtWorkspaceSpectrumData.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTAPI_QWTWORKSPACESPECTRUMDATA_H
-#define MANTIDQTAPI_QWTWORKSPACESPECTRUMDATA_H
+#pragma once
 
 #include "MantidAPI/MatrixWorkspace_fwd.h"
 #include "MantidKernel/cow_ptr.h"
@@ -115,5 +114,4 @@ private:
 
   ///// y-axis offset for waterfall plots
   // double m_offsetY;
-};
-#endif
+};
\ No newline at end of file
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/RangeSelector.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/RangeSelector.h
index d6568c9e90c907dd2db7e0d32f0bd7cfee024b6b..77f8601eeaef4b96113808201babf78fb9149a06 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/RangeSelector.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/RangeSelector.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGET_POSHPLOTTING_H
-#define MANTIDQT_MANTIDWIDGET_POSHPLOTTING_H
+#pragma once
 
 #include "MantidQtWidgets/Plotting/DllOption.h"
 
@@ -113,5 +112,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/SafeQwtPlot.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/SafeQwtPlot.h
index d68c5e69b2106289f9119b6b2ac4c62490808e5c..5bed1c3a385d9cf122f3b0a29f6157e206d74859 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/SafeQwtPlot.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/SafeQwtPlot.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_SAFEQWTPLOT_H_
-#define MANTID_MANTIDWIDGETS_SAFEQWTPLOT_H_
+#pragma once
 
 #include "MantidAPI/Workspace_fwd.h"
 #include "MantidKernel/WarningSuppressions.h"
@@ -50,5 +49,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTID_MANTIDWIDGETS_SAFEQWTPLOT_H_ */
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/ScaleEngine.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/ScaleEngine.h
index c17d78b257b8c97de79f0379d10d87eb8f128f9b..8a6667050281c60f343225f0c7afca1c7ae4f68a 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/ScaleEngine.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/ScaleEngine.h
@@ -27,8 +27,7 @@
  *   Boston, MA  02110-1301  USA                                           *
  *                                                                         *
  ***************************************************************************/
-#ifndef SCALE_ENGINE_H
-#define SCALE_ENGINE_H
+#pragma once
 
 #include "MantidQtWidgets/Plotting/DllOption.h"
 #include <float.h>
@@ -131,5 +130,3 @@ private:
   //! Nth Power for a power scale
   double d_nth_power;
 };
-
-#endif
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/SignalRange.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/SignalRange.h
index 50b9954bf5c6d7adef018453dcea8a06e61471e1..6b36b3c3cb7cb6f66d95b81322d2d95b7204665b 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/SignalRange.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/SignalRange.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_SIGNALRANGE_H_
-#define MANTIDQT_API_SIGNALRANGE_H_
+#pragma once
 
 #include "MantidAPI/IMDWorkspace.h"
 #include "MantidQtWidgets/Plotting/DllOption.h"
@@ -52,5 +51,3 @@ private:
 
 } // namespace API
 } // namespace MantidQt
-
-#endif /* MANTIDQT_API_SIGNALRANGE_H_ */
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/SingleSelector.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/SingleSelector.h
index a53e1ca9e44469c3ce6cf9c44efc924c788b4369..c370de236237a8bc5a07827ac08c46774c93ecf1 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/SingleSelector.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/SingleSelector.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGET_QWT_SINGLESELECTOR_H
-#define MANTIDQT_MANTIDWIDGET_QWT_SINGLESELECTOR_H
+#pragma once
 
 #include "MantidQtWidgets/Plotting/DllOption.h"
 
@@ -91,5 +90,3 @@ private:
 
 } // namespace MantidWidgets
 } // namespace MantidQt
-
-#endif /* MANTIDQT_MANTIDWIDGET_QWT_SINGLESELECTOR_H */
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/qwt_compat.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/qwt_compat.h
index 224066a8990157df3dd018b817a84f265d418a1f..a899c2461de19c5eddf377d6fce48149df746b0d 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/qwt_compat.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/Qwt/qwt_compat.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_QWT_COMPAT
-#define MANTID_QWT_COMPAT
+#pragma once
 
 #include <qwt_global.h>
 
@@ -23,5 +22,3 @@
 #define lowerMargin() loMargin()
 #define upperMargin() hiMargin()
 #endif /* QWT_VERSION >= 0x050200 */
-
-#endif /* MANTID_QWT_COMPAT */
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/RangeSelector.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/RangeSelector.h
index 01a2a40ce762113dd585f9443cb04630b7fcc7a4..c5dba623ac3811917439901a8891f6271549b638 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/RangeSelector.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/RangeSelector.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGET_RANGESELECTOR_H
-#define MANTIDQT_MANTIDWIDGET_RANGESELECTOR_H
+#pragma once
 
 #include <QtGlobal>
 
@@ -14,5 +13,3 @@
 #else
 #include "MantidQtWidgets/Plotting/Mpl/RangeSelector.h"
 #endif
-
-#endif // MANTIDQT_MANTIDWIDGET_RANGESELECTOR_H
diff --git a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/SingleSelector.h b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/SingleSelector.h
index 920f47e2cd5e66d0d463fd1cbf0a00189ad14cfc..93195ffa700405e861b7af3537ff56e84ba92615 100644
--- a/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/SingleSelector.h
+++ b/qt/widgets/plotting/inc/MantidQtWidgets/Plotting/SingleSelector.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDWIDGET_SINGLESELECTOR_H
-#define MANTIDQT_MANTIDWIDGET_SINGLESELECTOR_H
+#pragma once
 
 #include <QtGlobal>
 
@@ -14,5 +13,3 @@
 #else
 #include "MantidQtWidgets/Plotting/Mpl/SingleSelector.h"
 #endif
-
-#endif // MANTIDQT_MANTIDWIDGET_SINGLESELECTOR_H
diff --git a/qt/widgets/plotting/test/ContourPreviewPlotTest.h b/qt/widgets/plotting/test/ContourPreviewPlotTest.h
index dcd84d09ad694fc73cbd72031b0281f11b98fcde..87a8dc58819e82a118b0446c988db8f599475342 100644
--- a/qt/widgets/plotting/test/ContourPreviewPlotTest.h
+++ b/qt/widgets/plotting/test/ContourPreviewPlotTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_MANTIDCONTOURPREVIEWPLOTTEST_H_
-#define MANTIDQT_API_MANTIDCONTOURPREVIEWPLOTTEST_H_
+#pragma once
 
 #include <cxxtest/TestSuite.h>
 
@@ -68,5 +67,3 @@ public:
 private:
   std::unique_ptr<ContourPreviewPlot> m_contourPlot;
 };
-
-#endif /* MANTIDQT_API_MANTIDCONTOURPREVIEWPLOTTEST_H_ */
diff --git a/qt/widgets/plotting/test/MantidColorMapTest.h b/qt/widgets/plotting/test/MantidColorMapTest.h
index ff874db975b7ea944fdbba09b89cd84ce09ec438..e719d761b88b4d30ccec61c0168a6601cbfd0198 100644
--- a/qt/widgets/plotting/test/MantidColorMapTest.h
+++ b/qt/widgets/plotting/test/MantidColorMapTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_MANTIDCOLORMAPTEST_H_
-#define MANTIDQT_API_MANTIDCOLORMAPTEST_H_
+#pragma once
 
 #include "MantidQtWidgets/Plotting/Qwt/MantidColorMap.h"
 #include <QRgb>
@@ -72,5 +71,3 @@ public:
                       map.colorIndex(range, +123.0), 255);
   }
 };
-
-#endif /* MANTIDQT_API_MANTIDCOLORMAPTEST_H_ */
diff --git a/qt/widgets/plotting/test/PlottingTestInitialization.h b/qt/widgets/plotting/test/PlottingTestInitialization.h
index 5535e8570feeee94c3fd38e47baa6d20d53d5ef1..9573415f857281cf6152bd9e9b1925b408b86890 100644
--- a/qt/widgets/plotting/test/PlottingTestInitialization.h
+++ b/qt/widgets/plotting/test/PlottingTestInitialization.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef PLOTTINGTESTINITIALIZATION_H
-#define PLOTTINGTESTINITIALIZATION_H
+#pragma once
 #include "MantidQtWidgets/Common/Testing/QApplicationGlobalFixture.h"
 
 //------------------------------------------------------------------------------
@@ -15,5 +14,3 @@
 // statements do not cause multiple-definition errors.
 //------------------------------------------------------------------------------
 static QApplicationGlobalFixture MAIN_QAPPLICATION;
-
-#endif // PLOTTINGTESTINITIALIZATION_H
diff --git a/qt/widgets/plotting/test/QwtWorkspaceBinDataTest.h b/qt/widgets/plotting/test/QwtWorkspaceBinDataTest.h
index dfca24df44dae922012bca29ddccf7d046e3beb2..066383acdcfa62062b2a423f67ffa290ba129b58 100644
--- a/qt/widgets/plotting/test/QwtWorkspaceBinDataTest.h
+++ b/qt/widgets/plotting/test/QwtWorkspaceBinDataTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_MANTIDQWTWORKSPACEBINDATA_H_
-#define MANTIDQT_API_MANTIDQWTWORKSPACEBINDATA_H_
+#pragma once
 
 #include "MantidQtWidgets/Plotting/Qwt/QwtWorkspaceBinData.h"
 #include <cxxtest/TestSuite.h>
@@ -73,5 +72,3 @@ public:
     TS_ASSERT_DELTA(data.e(2), 0.0, 1e-6);
   }
 };
-
-#endif /* MANTIDQT_API_MANTIDQWTWORKSPACEBINDATA_H_ */
diff --git a/qt/widgets/plotting/test/QwtWorkspaceSpectrumDataTest.h b/qt/widgets/plotting/test/QwtWorkspaceSpectrumDataTest.h
index 15d5f2fe2480cf7c95b0b4153a34624a6268608d..684f9680f0ff8d79c386d50985e910f8a4c6a087 100644
--- a/qt/widgets/plotting/test/QwtWorkspaceSpectrumDataTest.h
+++ b/qt/widgets/plotting/test/QwtWorkspaceSpectrumDataTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_MANTIDQWTWORKSPACESPECTRUMDATA_H_
-#define MANTIDQT_API_MANTIDQWTWORKSPACESPECTRUMDATA_H_
+#pragma once
 
 #include "MantidAPI/MatrixWorkspace.h"
 #include "MantidQtWidgets/Plotting/Qwt/QwtWorkspaceSpectrumData.h"
@@ -74,5 +73,3 @@ public:
     TS_ASSERT_DELTA(data.e(2), 0.0, 1e-6);
   }
 };
-
-#endif /* MANTIDQT_API_MANTIDQWTWORKSPACESPECTRUMDATA_H_ */
diff --git a/qt/widgets/plotting/test/SignalRangeTest.h b/qt/widgets/plotting/test/SignalRangeTest.h
index 4365b10d788d3776bf8c1c0aca53f6a6952c7cd9..ed8bc2870b086440552fb77db6f919fb4af4961b 100644
--- a/qt/widgets/plotting/test/SignalRangeTest.h
+++ b/qt/widgets/plotting/test/SignalRangeTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_API_SIGNALRANGETEST_H_
-#define MANTIDQT_API_SIGNALRANGETEST_H_
+#pragma once
 
 #include "MantidAPI/IMDWorkspace.h"
 #include "MantidGeometry/MDGeometry/MDImplicitFunction.h"
@@ -224,5 +223,3 @@ public:
     TS_ASSERT_DELTA(5.0, range.maxValue(), 1e-10);
   }
 };
-
-#endif /* MANTIDQT_API_SIGNALRANGETEST */
diff --git a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/CatalogPublishDialog.h b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/CatalogPublishDialog.h
index 4e80ae6c2f83c5fa08b3cb2683aa512838f0c1a5..a427aeef5cc5271b18610bdcddb062a427aad05e 100644
--- a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/CatalogPublishDialog.h
+++ b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/CatalogPublishDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_CUSTOM_DIALOGS_CATALOGPUBLISHDIALOG_H
-#define MANTIDQT_CUSTOM_DIALOGS_CATALOGPUBLISHDIALOG_H
+#pragma once
 
 #include "MantidQtWidgets/Common/AlgorithmDialog.h"
 #include "ui_CatalogPublishDialog.h"
@@ -52,5 +51,3 @@ protected:
 };
 } // namespace CustomDialogs
 } // namespace MantidQt
-
-#endif /* MANTIDQT_CUSTOM_DIALOGS_CATALOGPUBLISHDIALOG_H */
diff --git a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/ConvertTableToMatrixWorkspaceDialog.h b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/ConvertTableToMatrixWorkspaceDialog.h
index 0d35ec8119c855e63d04a0a8327e352f4e6bdf2e..4d04394163af9b5e622e8748cce6e0c15dbb8f44 100644
--- a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/ConvertTableToMatrixWorkspaceDialog.h
+++ b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/ConvertTableToMatrixWorkspaceDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_CUSTOM_DIALOGS_CONVERTTABLETOMATRIXWORKSPACEDIALOG_H
-#define MANTIDQT_CUSTOM_DIALOGS_CONVERTTABLETOMATRIXWORKSPACEDIALOG_H
+#pragma once
 
 //------------------------------------------------------------------------------
 // Includes
@@ -56,5 +55,3 @@ private:
 };
 } // namespace CustomDialogs
 } // namespace MantidQt
-
-#endif // MANTIDQT_CUSTOM_DIALOGS_CONVERTTABLETOMATRIXWORKSPACEDIALOG_H
diff --git a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/FitDialog.h b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/FitDialog.h
index 17cc4ea440b239cf338569d75b00782b1151f469..f8e067cc89eac03fafa0317c9d3965b268ca1980 100644
--- a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/FitDialog.h
+++ b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/FitDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_CUSTOM_DIALOGS_FITDIALOG_H
-#define MANTIDQT_CUSTOM_DIALOGS_FITDIALOG_H
+#pragma once
 
 //------------------------------------------------------------------------------
 // Includes
@@ -206,5 +205,3 @@ protected:
 };
 } // namespace CustomDialogs
 } // namespace MantidQt
-
-#endif // MANTIDQT_CUSTOM_DIALOGS_FITDIALOG_H
diff --git a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/LOQScriptInputDialog.h b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/LOQScriptInputDialog.h
index 9ba16b8309b44fdcfbf55c95f808d47432270bde..f5abc8a928b8c0f5a7dc569ce0c831d00d59fab8 100644
--- a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/LOQScriptInputDialog.h
+++ b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/LOQScriptInputDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_CUSTOMDIALOGS_LOQSCRIPTINPUTDIALOG_H_
-#define MANTIDQT_CUSTOMDIALOGS_LOQSCRIPTINPUTDIALOG_H_
+#pragma once
 
 //---------------------------
 // Includes
@@ -47,5 +46,3 @@ private:
 };
 } // namespace CustomDialogs
 } // namespace MantidQt
-
-#endif // MANTIDQT_CUSTOMDIALOGS_LOQSCRIPTINPUTDIALOG_H_
diff --git a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/LoadDAEDialog.h b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/LoadDAEDialog.h
index b219fc8fd985affdbf9f6b0857f137b1f7f05f34..1d75d6f5e764d6d5e92126bdae89536ec03c69a2 100644
--- a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/LoadDAEDialog.h
+++ b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/LoadDAEDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_CUSTOM_DIALOGSLOADDAEDIALOG_H
-#define MANTIDQT_CUSTOM_DIALOGSLOADDAEDIALOG_H
+#pragma once
 
 //----------------------
 // Includes
@@ -55,5 +54,3 @@ private:
 };
 } // namespace CustomDialogs
 } // namespace MantidQt
-
-#endif /* MANTIDQT_CUSTOM_DIALOGSLOADDAEDIALOG_H */
diff --git a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/LoadDialog.h b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/LoadDialog.h
index 981c08091b430e37c18eb5f0079c17ed419dc801..120e245bf3d5c51d3f56a2a0de32bf55ad71eb6a 100644
--- a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/LoadDialog.h
+++ b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/LoadDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_CUSTOM_DIALOGS_LOADDIALOG_H
-#define MANTIDQT_CUSTOM_DIALOGS_LOADDIALOG_H
+#pragma once
 
 //------------------------------------------------------------------------------
 // Includes
@@ -99,5 +98,3 @@ private:
 };
 } // namespace CustomDialogs
 } // namespace MantidQt
-
-#endif // MANTIDQT_CUSTOM_DIALOGS_LOADDIALOG_H
diff --git a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/LoadRawDialog.h b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/LoadRawDialog.h
index 45aeebf801dee47e22833235af6a6546ff80facc..114c8716fd72cda581da9dd9219a153b83c02ebe 100644
--- a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/LoadRawDialog.h
+++ b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/LoadRawDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_CUSTOM_DIALOGSLOADRAWDIALOG_H
-#define MANTIDQT_CUSTOM_DIALOGSLOADRAWDIALOG_H
+#pragma once
 
 //----------------------
 // Includes
@@ -59,5 +58,3 @@ private:
 };
 } // namespace CustomDialogs
 } // namespace MantidQt
-
-#endif // MANTIDQT_CUSTOMDIALOGS_LOADRAWDIALOG_H
diff --git a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/MantidGLWidget.h b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/MantidGLWidget.h
index 760eb69600450fbea6a64c44aff5d34f8e0e5105..8d101ef29c00b00e8a40cf327dc327d1b3394e04 100644
--- a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/MantidGLWidget.h
+++ b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/MantidGLWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_CUSTOMDIALOGS_MANTIDGLWIDGET_H_
-#define MANTIDQT_CUSTOMDIALOGS_MANTIDGLWIDGET_H_
+#pragma once
 
 //-----------------------------------------
 // Includes
@@ -87,5 +86,3 @@ private:
 };
 } // namespace CustomDialogs
 } // namespace MantidQt
-
-#endif // MANTIDQT_CUSTOMDIALOGS_MANTIDGLWIDGET_H_
diff --git a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/PeriodicTableWidget.h b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/PeriodicTableWidget.h
index e59a2ff2212f954fa6b1ae295a1c4debb695c9df..f4a45032653d588067d5dd42dad3ce2fba4a1ab8 100644
--- a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/PeriodicTableWidget.h
+++ b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/PeriodicTableWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_MANTIDWIDGETS_PERIODICTABLEWIDGET_H_
-#define MANTID_MANTIDWIDGETS_PERIODICTABLEWIDGET_H_
+#pragma once
 
 #include "MantidQtWidgets/Common/DllOption.h"
 #include "ui_PeriodicTableWidget.h"
@@ -98,5 +97,3 @@ private:
   /// Colour all of the elements by calls to individual group colouring methods
   void ColourElements();
 };
-
-#endif // !MANTID_MANTIDWIDGETS_PERIODICTABLE_H_
diff --git a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/PlotAsymmetryByLogValueDialog.h b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/PlotAsymmetryByLogValueDialog.h
index 2bf7220465501276303f6c54b12ed0b8c18dde13..24214b9259bd296b44a4bad954460e0b46ebb60f 100644
--- a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/PlotAsymmetryByLogValueDialog.h
+++ b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/PlotAsymmetryByLogValueDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_CUSTOM_DIALOGSLPLOTASYMMETRYBYLOGVALUEDIALOG_H
-#define MANTIDQT_CUSTOM_DIALOGSLPLOTASYMMETRYBYLOGVALUEDIALOG_H
+#pragma once
 
 //----------------------
 // Includes
@@ -70,5 +69,3 @@ private:
 };
 } // namespace CustomDialogs
 } // namespace MantidQt
-
-#endif // MANTIDQT_CUSTOM_DIALOGSLPLOTASYMMETRYBYLOGVALUEDIALOG_H
diff --git a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/PrecompiledHeader.h b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/PrecompiledHeader.h
index 0c414a78f6b0ba4f01eaf7132049229805d0ff0e..615c906d96f4ca5650f269d34d7bc61092dd5111 100644
--- a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/PrecompiledHeader.h
+++ b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/PrecompiledHeader.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_CUSTOMDIALOGS_PRECOMPILEDHEADER_H_
-#define MANTIDQT_CUSTOMDIALOGS_PRECOMPILEDHEADER_H_
+#pragma once
 
 // Mantid
 #include "MantidAPI/Algorithm.h"
@@ -22,5 +21,3 @@
 #include <set>
 #include <string>
 #include <vector>
-
-#endif // MANTIDQT_CUSTOMDIALOGS_PRECOMPILEDHEADER_H_
\ No newline at end of file
diff --git a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/SampleShapeHelpers.h b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/SampleShapeHelpers.h
index 84ee29646bb89daae7f27b0671795aacb029ad27..63cef82cd39400eeac012e341f976dbf1a68fbd7 100644
--- a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/SampleShapeHelpers.h
+++ b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/SampleShapeHelpers.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_CUSTOMDIALOGS_SAMPLESHAPEHELPERS_H_
-#define MANTIDQT_CUSTOMDIALOGS_SAMPLESHAPEHELPERS_H_
+#pragma once
 
 //--------------------------------------
 // Includes
@@ -436,5 +435,3 @@ private:
 // };
 } // namespace CustomDialogs
 } // namespace MantidQt
-
-#endif // MANTIDQT_CUSTOMDIALOGS_SAMPLESHAPEHELPERS_H_
diff --git a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/SmoothNeighboursDialog.h b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/SmoothNeighboursDialog.h
index e820baf78c1b17661f4379b5b1f8d47be8457248..6daa898af8979a8e63685081feb608211575652f 100644
--- a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/SmoothNeighboursDialog.h
+++ b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/SmoothNeighboursDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SMOOTH_NEIGHBOURS_DIALOG_H_
-#define SMOOTH_NEIGHBOURS_DIALOG_H_
+#pragma once
 
 #include "MantidQtWidgets/Common/AlgorithmDialog.h"
 #include "MantidQtWidgets/Common/AlgorithmPropertiesWidget.h"
@@ -42,5 +41,3 @@ private:
   /// Main layout for the dialog
   QVBoxLayout *m_dialogLayout;
 };
-
-#endif
diff --git a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/SortTableWorkspaceDialog.h b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/SortTableWorkspaceDialog.h
index 233aa83493bccb75adb5fa6f45c21aca938cb501..1d3490dd44cf133dd7fde3261bc47e78a76dee03 100644
--- a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/SortTableWorkspaceDialog.h
+++ b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/SortTableWorkspaceDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_CUSTOM_DIALOGS_SORTTABLEWORKSPACEDIALOG_H
-#define MANTIDQT_CUSTOM_DIALOGS_SORTTABLEWORKSPACEDIALOG_H
+#pragma once
 
 //------------------------------------------------------------------------------
 // Includes
@@ -61,5 +60,3 @@ private:
 
 } // namespace CustomDialogs
 } // namespace MantidQt
-
-#endif // MANTIDQT_CUSTOM_DIALOGS_SORTTABLEWORKSPACEDIALOG_H
diff --git a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/StartLiveDataDialog.h b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/StartLiveDataDialog.h
index 2f9e3b69cf11aaf81ca47d540b349ad67708af38..362c4055f9a74292c412959c4fec4c2f9f62c8c8 100644
--- a/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/StartLiveDataDialog.h
+++ b/qt/widgets/plugins/algorithm_dialogs/inc/MantidQtWidgets/Plugins/AlgorithmDialogs/StartLiveDataDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQTCUSTOMDIALOGS_STARTLIVEDATADIALOG_H_
-#define MANTIDQTCUSTOMDIALOGS_STARTLIVEDATADIALOG_H_
+#pragma once
 
 //----------------------
 // Includes
@@ -77,5 +76,3 @@ private:
 };
 } // namespace CustomDialogs
 } // namespace MantidQt
-
-#endif // MANTIDQTCUSTOMDIALOGS_STARTLIVEDATADIALOG_H_
diff --git a/qt/widgets/plugins/designer/inc/MantidQtWidgets/Plugins/Designer/DesignerPlugin.h b/qt/widgets/plugins/designer/inc/MantidQtWidgets/Plugins/Designer/DesignerPlugin.h
index 66ae70ef2ba85cb88266544667084e6fa3acf668..c210ae8e81224af64054dc464ffd32fa8764d5d8 100644
--- a/qt/widgets/plugins/designer/inc/MantidQtWidgets/Plugins/Designer/DesignerPlugin.h
+++ b/qt/widgets/plugins/designer/inc/MantidQtWidgets/Plugins/Designer/DesignerPlugin.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DesignerPlugin_H
-#define DesignerPlugin_H
+#pragma once
 
 #include <QDesignerCustomWidgetInterface>
 
@@ -57,5 +56,3 @@ private:
   /// Are we initialized?
   bool m_initialized;
 };
-
-#endif
diff --git a/qt/widgets/plugins/designer/inc/MantidQtWidgets/Plugins/Designer/PluginCollectionInterface.h b/qt/widgets/plugins/designer/inc/MantidQtWidgets/Plugins/Designer/PluginCollectionInterface.h
index d441d67b124cb5acf26e3326f480c5a4e91c669b..d919d6656eefc1e4b63cf30bf2376a8610e2af8f 100644
--- a/qt/widgets/plugins/designer/inc/MantidQtWidgets/Plugins/Designer/PluginCollectionInterface.h
+++ b/qt/widgets/plugins/designer/inc/MantidQtWidgets/Plugins/Designer/PluginCollectionInterface.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef PLUGINCOLLECTIONINTERFACE_H_
-#define PLUGINCOLLECTIONINTERFACE_H_
+#pragma once
 
 #include "MantidQtWidgets/Common/AlgorithmPropertiesWidget.h"
 #include "MantidQtWidgets/Common/AlgorithmSelectorWidget.h"
@@ -153,5 +152,3 @@ DECLARE_WIDGET_PLUGIN(MuonFitDataSelectorPlugin,
 DECLARE_WIDGET_PLUGIN(LogValueSelectorPlugin,
                       MantidQt::MantidWidgets::LogValueSelector,
                       "Select a log name and function");
-
-#endif
diff --git a/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/DllOption.h b/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/DllOption.h
index 6ed5be99e08b4b4ab074694b0aa02cef63ecf985..675489ce2a1a3c0b1bad20462fc1994af7ee550d 100644
--- a/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/DllOption.h
+++ b/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/DllOption.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTID_REFDETECTORVIEWER_DLLOPTION_H_
-#define MANTIDQT_MANTID_REFDETECTORVIEWER_DLLOPTION_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 
@@ -14,5 +13,3 @@
 #else
 #define EXPORT_OPT_MANTIDQT_REFDETECTORVIEWER DLLImport
 #endif
-
-#endif // MANTIDQT_MANTID_REFDETECTORVIEWER_DLLOPTION_H_
diff --git a/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefIVConnections.h b/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefIVConnections.h
index b07e569e60c91ff2f317bdeb701f5bd50b09319b..e24fc4a1789de9bbda175e50c676565870769844 100644
--- a/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefIVConnections.h
+++ b/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefIVConnections.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef REF_IV_CONNECTIONS_H
-#define REF_IV_CONNECTIONS_H
+#pragma once
 
 #include <QActionGroup>
 #include <QWidget>
@@ -101,5 +100,3 @@ private:
 
 } // namespace RefDetectorViewer
 } // namespace MantidQt
-
-#endif // REF_IV_CONNECTIONS_H
diff --git a/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefImageDisplay.h b/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefImageDisplay.h
index 74863e29cdcb050b3d4fcc3c38475af188d851b5..a2a68e0ff3ca2acc7a5e9fde6eea6a82dc9a2259 100644
--- a/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefImageDisplay.h
+++ b/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefImageDisplay.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef REF_IMAGE_DISPLAY_H
-#define REF_IMAGE_DISPLAY_H
+#pragma once
 
 #include "DllOption.h"
 #include "MantidQtWidgets/RefDetectorView/RefLimitsHandler.h"
@@ -46,5 +45,3 @@ private:
 
 } // namespace RefDetectorViewer
 } // namespace MantidQt
-
-#endif // REF_IMAGE_DISPLAY_H
diff --git a/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefImagePlotItem.h b/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefImagePlotItem.h
index 6ab6665d566685e2147effc03996059a98065f8f..f7d534fde3813967af15454d79f322d468b5579e 100644
--- a/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefImagePlotItem.h
+++ b/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefImagePlotItem.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef REF_IMAGE_PLOT_ITEM_H
-#define REF_IMAGE_PLOT_ITEM_H
+#pragma once
 
 #include "DllOption.h"
 #include "MantidQtWidgets/RefDetectorView/RefLimitsHandler.h"
@@ -37,5 +36,3 @@ private:
 
 } // namespace RefDetectorViewer
 } // namespace MantidQt
-
-#endif // REF_IMAGE_PLOT_ITEM_H
diff --git a/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefImageView.h b/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefImageView.h
index e74691824704c1bdcf0ef5ee64c0ca40c3dddceb..1ec75607b00d66bafa255afd1cd25ded5e887a57 100644
--- a/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefImageView.h
+++ b/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefImageView.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef REF_IMAGE_VIEW_H
-#define REF_IMAGE_VIEW_H
+#pragma once
 
 #include <QMainWindow>
 
@@ -58,5 +57,3 @@ private:
 
 } // namespace RefDetectorViewer
 } // namespace MantidQt
-
-#endif // REF_IMAGE_VIEW_H
diff --git a/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefLimitsHandler.h b/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefLimitsHandler.h
index 3cf3de219ef5842854202b9758584942456eb162..cd27e9b1d08ce2a21d79e616a76a2e8b6722a031 100644
--- a/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefLimitsHandler.h
+++ b/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefLimitsHandler.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef REF_LIMITS_HANDLER_H
-#define REF_LIMITS_HANDLER_H
+#pragma once
 
 #include "ui_RefImageView.h"
 
@@ -42,5 +41,3 @@ private:
 
 } // namespace RefDetectorViewer
 } // namespace MantidQt
-
-#endif // REF_LIMITS_HANDLER_H
diff --git a/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefMatrixWSImageView.h b/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefMatrixWSImageView.h
index 9507da07d77e7a5505909d8df823d66ac1a0e64f..2a8343a38a14d058e94a745fb893b0aac79646ef 100644
--- a/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefMatrixWSImageView.h
+++ b/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefMatrixWSImageView.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef REF_MATRIX_WS_IMAGE_VIEW_H
-#define REF_MATRIX_WS_IMAGE_VIEW_H
+#pragma once
 
 #include "DllOption.h"
 #include "MantidAPI/Algorithm.h"
@@ -45,5 +44,3 @@ private:
 
 } // namespace RefDetectorViewer
 } // namespace MantidQt
-
-#endif // REF_MATRIX_WS_IMAGE_VIEW_H
diff --git a/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefRangeHandler.h b/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefRangeHandler.h
index 02c056952d6ebe214d6f7909a0121c85137924bb..27b0a4e3b359087a46bd9d16ad644abdb3d0d292 100644
--- a/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefRangeHandler.h
+++ b/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefRangeHandler.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef REF_RANGE_HANDLER_H
-#define REF_RANGE_HANDLER_H
+#pragma once
 
 #include "DllOption.h"
 #include "MantidQtWidgets/SpectrumViewer/IRangeHandler.h"
@@ -53,5 +52,3 @@ private:
 
 } // namespace RefDetectorViewer
 } // namespace MantidQt
-
-#endif // REF_RANGE_HANDLER_H
diff --git a/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefSliderHandler.h b/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefSliderHandler.h
index 7f97ed5fb1d91b3e669c8b2c063168f9c74d84cc..c70ebc34db99a1bbe43d81dec8162dd0fa9b85d6 100644
--- a/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefSliderHandler.h
+++ b/qt/widgets/refdetectorview/inc/MantidQtWidgets/RefDetectorView/RefSliderHandler.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef REF_SLIDER_HANDLER_H
-#define REF_SLIDER_HANDLER_H
+#pragma once
 
 #include "MantidQtWidgets/SpectrumViewer/ISliderHandler.h"
 #include <QRect>
@@ -63,5 +62,3 @@ private:
 
 } // namespace RefDetectorViewer
 } // namespace MantidQt
-
-#endif // REF_SLIDER_HANDLER_H
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/CompositePeaksPresenter.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/CompositePeaksPresenter.h
index 38c055f01a3047fc5957e4352a6d870e6fd192c8..01bb1d1503ae3dd4fc37349005e810cf49439dde 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/CompositePeaksPresenter.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/CompositePeaksPresenter.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_COMPOSITEPEAKSPRESENTER_H_
-#define MANTID_SLICEVIEWER_COMPOSITEPEAKSPRESENTER_H_
+#pragma once
 
 #include "MantidQtWidgets/SliceViewer/NullPeaksPresenter.h"
 #include "MantidQtWidgets/SliceViewer/PeakBoundingBox.h"
@@ -201,5 +200,3 @@ private:
 };
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/ConcretePeaksPresenter.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/ConcretePeaksPresenter.h
index 154122bd7570ded8e81e0c4ba0be709b3d1204c8..ad0af8ebc7b5ffb53d4a101805913c611f836962 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/ConcretePeaksPresenter.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/ConcretePeaksPresenter.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_CONCRETEPEAKSPRESENTER_H_
-#define MANTID_SLICEVIEWER_CONCRETEPEAKSPRESENTER_H_
+#pragma once
 #include "MantidAPI/IPeaksWorkspace_fwd.h"
 #include "MantidAPI/MDGeometry.h"
 #include "MantidGeometry/Crystal/PeakTransform.h"
@@ -122,5 +121,3 @@ private:
 };
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif /* MANTID_SLICEVIEWER_CONCRETEPEAKSPRESENTER_H_ */
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/CoordinateTransform.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/CoordinateTransform.h
index 456cec53833854aae7faf540edf342d0403a421b..e73a4c2cde61640811a75a63924015a75a99d9a2 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/CoordinateTransform.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/CoordinateTransform.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_SLICEVIEWER_COORDINATETRANSFORM_H
-#define MANTIDQT_SLICEVIEWER_COORDINATETRANSFORM_H
+#pragma once
 
 #include "DllOption.h"
 #include "MantidAPI/IMDWorkspace.h"
@@ -53,5 +52,4 @@ std::unique_ptr<CoordinateTransform> EXPORT_OPT_MANTIDQT_SLICEVIEWER
 createCoordinateTransform(const Mantid::API::IMDWorkspace &ws, size_t dimX,
                           size_t dimY);
 } // namespace SliceViewer
-} // namespace MantidQt
-#endif
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/CustomTools.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/CustomTools.h
index 856afcf42237d6145fffa561cb95215c9b3f1dd2..dad053a099e9d4fd5843634a1ce2a57210264577 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/CustomTools.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/CustomTools.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef CUSTOMTOOLS_H_
-#define CUSTOMTOOLS_H_
+#pragma once
 #include <QMouseEvent>
 #include <qwt_picker_machine.h>
 #include <qwt_plot_canvas.h>
@@ -96,5 +95,3 @@ protected:
 
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif /* CUSTOMTOOLS_H_ */
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/DimensionSliceWidget.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/DimensionSliceWidget.h
index 89d4278ce4945132881daf17243841e4b65f8e0f..9c8d23f5b4b833ce8edb7df7aa09b0e585d70d34 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/DimensionSliceWidget.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/DimensionSliceWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DIMENSIONSLICEWIDGET_H
-#define DIMENSIONSLICEWIDGET_H
+#pragma once
 
 #include "DllOption.h"
 #include "MantidGeometry/MDGeometry/IMDDimension.h"
@@ -97,5 +96,3 @@ private:
 
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif // DIMENSIONSLICEWIDGET_H
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/DllOption.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/DllOption.h
index 18bcf56599f13cb898e5298dd32af2995cbbb177..7297da09506abf2c15d2b5922759532a4f5f32ba 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/DllOption.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/DllOption.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTIDSLICEVIEWER_DLLOPTION_H_
-#define MANTIDQT_MANTIDSLICEVIEWER_DLLOPTION_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 
@@ -14,5 +13,3 @@
 #else
 #define EXPORT_OPT_MANTIDQT_SLICEVIEWER DLLImport
 #endif
-
-#endif // MANTIDQT_MANTIDSLICEVIEWER_DLLOPTION_H_
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/EllipsoidPlaneSliceCalculator.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/EllipsoidPlaneSliceCalculator.h
index 76883473cb4c52d21dbab460800ce3c1cdf2bb50..c2e57bab98fb2189f9459ee3fadd7e0e075efdf6 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/EllipsoidPlaneSliceCalculator.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/EllipsoidPlaneSliceCalculator.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_ELLIPSOID_PLANE_SLICE_CALCULATOR_H_
-#define MANTID_SLICEVIEWER_ELLIPSOID_PLANE_SLICE_CALCULATOR_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidKernel/Matrix.h"
@@ -74,5 +73,3 @@ private:
 };
 } // namespace SliceViewer
 } // namespace Mantid
-
-#endif
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/FirstExperimentInfoQuery.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/FirstExperimentInfoQuery.h
index 79d2db844ba37ade7523842450b3b01c4ca836cd..f74556092470bddce46b6a55b3f15a6954b88058 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/FirstExperimentInfoQuery.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/FirstExperimentInfoQuery.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_FIRSTEXPERIMENTINFOQUERY_H_
-#define MANTID_SLICEVIEWER_FIRSTEXPERIMENTINFOQUERY_H_
+#pragma once
 
 #include "MantidAPI/IMDWorkspace.h"
 #include "MantidAPI/MultipleExperimentInfos.h"
@@ -75,5 +74,3 @@ public:
 };
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif /* MANTID_SLICEVIEWER_FIRSTEXPERIMENTINFOQUERY_H_ */
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/LineOverlay.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/LineOverlay.h
index 276a687a45d838e3e5c72eb194b381f8b48472b5..cb071cda05d54a724a989d67d710283c5e4a728f 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/LineOverlay.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/LineOverlay.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_LINEOVERLAY_H_
-#define MANTID_SLICEVIEWER_LINEOVERLAY_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidKernel/System.h"
@@ -158,5 +157,3 @@ protected:
 
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif /* MANTID_SLICEVIEWER_LINEOVERLAY_H_ */
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/LinePlotOptions.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/LinePlotOptions.h
index 8ea943b4a1a17c29ebdf441d76d4990891ca57d0..1eb3df3d6e338e12857128a6d220afcdb76b00cd 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/LinePlotOptions.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/LinePlotOptions.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LINEPLOTOPTIONS_H
-#define LINEPLOTOPTIONS_H
+#pragma once
 
 #include "DllOption.h"
 #include "MantidAPI/IMDWorkspace.h"
@@ -61,5 +60,3 @@ private:
   /// Chosen normalization method
   Mantid::API::MDNormalization m_normalize;
 };
-
-#endif // LINEPLOTOPTIONS_H
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/LineViewer.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/LineViewer.h
index 3ac480e46b11b19bc47c4babbd41c42b46ed1586..93321e86a3e9efc771b6392b33da062d44d03243 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/LineViewer.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/LineViewer.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef LINEVIEWER_H
-#define LINEVIEWER_H
+#pragma once
 
 #include "DllOption.h"
 #include "MantidAPI/CoordTransform.h"
@@ -183,5 +182,4 @@ private:
 };
 
 } // namespace SliceViewer
-} // namespace MantidQt
-#endif // LINEVIEWER_H
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/NonOrthogonalAxis.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/NonOrthogonalAxis.h
index f09b1a66365d3576c4b6c92b7f7b24021c477dbd..c5ee98aa14d6040ecda16a709994279e947f7e95 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/NonOrthogonalAxis.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/NonOrthogonalAxis.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_NONORTHOGONAL_AXIS_H_
-#define MANTID_SLICEVIEWER_NONORTHOGONAL_AXIS_H_
+#pragma once
 
 #include "MantidGeometry/MDGeometry/MDTypes.h"
 #include <array>
@@ -22,5 +21,3 @@ struct NonOrthogonalAxis {
 
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/NonOrthogonalOverlay.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/NonOrthogonalOverlay.h
index 3bb4fb880cc54640c5b74475eea1c6fada29b981..6f00e2648ece97e72d1ff47d072d4ad9e8515c6c 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/NonOrthogonalOverlay.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/NonOrthogonalOverlay.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_NONORTHOGONALOVERLAY_H_
-#define MANTID_SLICEVIEWER_NONORTHOGONALOVERLAY_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidAPI/IMDEventWorkspace.h"
@@ -73,5 +72,3 @@ private:
 
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif /* MANTID_SLICEVIEWER_NONORTHOGONALOVERLAY_H_ */
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/NullPeaksPresenter.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/NullPeaksPresenter.h
index 6dba37ae31c45e7b6805eda9fb55b9978dca7c83..408a0a30e6ce1dc26110be07639ecc289cff0469 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/NullPeaksPresenter.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/NullPeaksPresenter.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_NULLPEAKSPRESENTER_H_
-#define MANTID_SLICEVIEWER_NULLPEAKSPRESENTER_H_
+#pragma once
 
 #include "MantidQtWidgets/SliceViewer/PeakBoundingBox.h"
 #include "MantidQtWidgets/SliceViewer/PeaksPresenter.h"
@@ -89,5 +88,3 @@ public:
 };
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif /* MANTID_SLICEVIEWER_NULLPEAKSPRESENTER_H_ */
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakBoundingBox.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakBoundingBox.h
index 44dc3df81b23c93271a08c70802f60026f120fb1..8ffff34e9e16b3ae42f082bd5332cbfe13c50d5a 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakBoundingBox.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakBoundingBox.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_PEAK_BOUNDING_BOX_H_
-#define MANTID_SLICEVIEWER_PEAK_BOUNDING_BOX_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidGeometry/Crystal/PeakTransform.h"
@@ -111,5 +110,3 @@ public:
 };
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif /* MANTID_SLICEVIEWER_PEAK_BOUNDING_BOX_H_ */
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakEditMode.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakEditMode.h
index e3ba411f7898d8cc8d3fa196268ebfc420201b92..23f0e92949595f2a77be6ad27b731ee4bcf66728 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakEditMode.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakEditMode.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_EDITMODE_H_
-#define MANTID_SLICEVIEWER_EDITMODE_H_
+#pragma once
 
 namespace MantidQt {
 namespace SliceViewer {
@@ -13,5 +12,4 @@ namespace SliceViewer {
 // Possible edit modes.
 enum EditMode { None = 0, AddPeaks = 1, DeletePeaks = 2 };
 } // namespace SliceViewer
-} // namespace MantidQt
-#endif
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakOverlayInteractive.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakOverlayInteractive.h
index 850019eff3dad35edf79cc699490f7328850cd02..2d05dfacf4129b64c97ea87ffd64e18748c28a6a 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakOverlayInteractive.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakOverlayInteractive.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_PEAKOVERLAYINTERACTIVE_H_
-#define MANTID_SLICEVIEWER_PEAKOVERLAYINTERACTIVE_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidQtWidgets/SliceViewer/PeakOverlayView.h"
@@ -91,5 +90,3 @@ private slots:
 };
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif // MANTID_SLICEVIEWER_PEAKOVERLAYINTERACTIVE_H_
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakOverlayView.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakOverlayView.h
index 49ed01ad95b1b2c12643bfa9c22aa990e7167e8d..e526c9f7dbfafbc63e105036d6175d7f10047b61 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakOverlayView.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakOverlayView.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_PEAKOVERLAY_VIEW_H_
-#define MANTID_SLICEVIEWER_PEAKOVERLAY_VIEW_H_
+#pragma once
 
 #include "MantidDataObjects/AffineMatrixParameter.h"
 #include "MantidGeometry/Crystal/PeakTransform.h"
@@ -86,5 +85,3 @@ using PeakOverlayView_const_sptr = boost::shared_ptr<const PeakOverlayView>;
 using PeakOverlayView_sptr = boost::shared_ptr<PeakOverlayView>;
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif /* MANTID_SLICEVIEWER_PEAKOVERLAY_VIEW_H_ */
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakOverlayViewFactory.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakOverlayViewFactory.h
index b8194fed2e48f05bb78798d0855f6f8a9f306ca7..66551555073be756d56ffae2380b6eaee619c0a0 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakOverlayViewFactory.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakOverlayViewFactory.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_PEAKOVERLAY_VIEW_FACTORY_H_
-#define MANTID_SLICEVIEWER_PEAKOVERLAY_VIEW_FACTORY_H_
+#pragma once
 
 #include "MantidGeometry/Crystal/PeakTransform.h"
 #include "MantidKernel/V3D.h"
@@ -54,5 +53,3 @@ public:
 using PeakOverlayViewFactory_sptr = boost::shared_ptr<PeakOverlayViewFactory>;
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif /* MANTID_SLICEVIEWER_PEAKOVERLAY_VIEW_FACTORY_H_ */
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakOverlayViewFactoryBase.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakOverlayViewFactoryBase.h
index 495b4b26a3fe3ea6c4faf48587bd4d1fd4ee469d..14a2e09d158259e0e55e6fef033b77203c15b774 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakOverlayViewFactoryBase.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakOverlayViewFactoryBase.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_PEAKOVERLAYVIEWFACTORYBASE_H_
-#define MANTID_SLICEVIEWER_PEAKOVERLAYVIEWFACTORYBASE_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidQtWidgets/SliceViewer/PeakOverlayViewFactory.h"
@@ -41,5 +40,3 @@ public:
 };
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif /*MANTID_SLICEVIEWER_PEAKOVERLAYVIEWFACTORYBASE_H_*/
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakPalette.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakPalette.h
index a363ac2e5045fe290172dda8080488ae75effa0d..4a4c1020e15d27163bdd4eed0f03b49f935524b5 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakPalette.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakPalette.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_PEAKPALETTE_H
-#define MANTID_SLICEVIEWER_PEAKPALETTE_H
+#pragma once
 
 #include "MantidKernel/System.h"
 #include "MantidQtWidgets/SliceViewer/PeakViewColor.h"
@@ -140,5 +139,4 @@ template <> DLLExport PeakPalette<QColor>::PeakPalette();
 template <> DLLExport PeakPalette<PeakViewColor>::PeakPalette();
 
 } // namespace SliceViewer
-} // namespace MantidQt
-#endif // MANTID_SLICEVIEWER_PEAKSPALETTE_H
\ No newline at end of file
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakPrimitives.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakPrimitives.h
index 8a7a321b6203fa8a71606a43b9cb6c129d69e8ad..77dcebf7916dea10abe7c70041905af71fa248ed 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakPrimitives.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakPrimitives.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_PEAK_PRIMITIVES_H
-#define MANTID_SLICEVIEWER_PEAK_PRIMITIVES_H
+#pragma once
 
 #include "DllOption.h"
 #include "MantidKernel/V3D.h"
@@ -86,5 +85,3 @@ struct EXPORT_OPT_MANTIDQT_SLICEVIEWER PeakPrimitivesEllipse
 };
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakRepresentation.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakRepresentation.h
index 9c1cfb8e4bd38f05462dd2f1d87aea5a820e0faf..0dcd0060b72355eca476c93b8495011e679b7442 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakRepresentation.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakRepresentation.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_PEAK_REPRESENTATION_H
-#define MANTID_SLICEVIEWER_PEAK_REPRESENTATION_H
+#pragma once
 
 #include "MantidDataObjects/AffineMatrixParameter.h"
 #include "MantidGeometry/Crystal/PeakTransform.h"
@@ -76,5 +75,3 @@ using PeakRepresentation_sptr = std::shared_ptr<PeakRepresentation>;
 using VecPeakRepresentation = std::vector<PeakRepresentation_sptr>;
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakRepresentationCross.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakRepresentationCross.h
index 789c81c9a58fcc70aecdc38e2c5581336207a89a..2807b3e4bd42b339ff8e4733a4695203d76ede6c 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakRepresentationCross.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakRepresentationCross.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_PEAK_REPRESENTATION_CROSS_H
-#define MANTID_SLICEVIEWER_PEAK_REPRESENTATION_CROSS_H
+#pragma once
 
 #include "MantidQtWidgets/SliceViewer/NonOrthogonalAxis.h"
 #include "MantidQtWidgets/SliceViewer/PeakRepresentation.h"
@@ -86,5 +85,4 @@ private:
   double m_slicePoint;
 };
 } // namespace SliceViewer
-} // namespace MantidQt
-#endif
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakRepresentationEllipsoid.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakRepresentationEllipsoid.h
index 47682a1ba0ceb5eacd36cf307ab3f17687ced49d..886fee6a08378331d008b7e63a3fdff2778d7350 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakRepresentationEllipsoid.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakRepresentationEllipsoid.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_PEAK_REPRESENTATION_ELLIPSOID_H
-#define MANTID_SLICEVIEWER_PEAK_REPRESENTATION_ELLIPSOID_H
+#pragma once
 
 #include "MantidKernel/V2D.h"
 #include "MantidQtWidgets/SliceViewer/EllipsoidPlaneSliceCalculator.h"
@@ -114,5 +113,4 @@ private:
       m_calculator;
 };
 } // namespace SliceViewer
-} // namespace MantidQt
-#endif
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakRepresentationSphere.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakRepresentationSphere.h
index fa6a5317a64dbc42416ec305f4b988de396cd6b7..fe6ce19466f797e8e417a8316ae0aca328572639 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakRepresentationSphere.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakRepresentationSphere.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_PEAK_REPRESENTATION_SPHERE_H
-#define MANTID_SLICEVIEWER_PEAK_REPRESENTATION_SPHERE_H
+#pragma once
 
 #include "MantidQtWidgets/SliceViewer/PeakRepresentation.h"
 
@@ -97,5 +96,4 @@ private:
   const double zoomOutFactor = 2.;
 };
 } // namespace SliceViewer
-} // namespace MantidQt
-#endif
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakView.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakView.h
index 350783b589d5446a09120fdf6481a3bf7eb51821..cf59b94983ba1a616247cbe57bfb9dbf49ad62ab 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakView.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakView.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_PEAK_VIEW_H_
-#define MANTID_SLICEVIEWER_PEAK_VIEW_H_
+#pragma once
 
 #include "MantidQtWidgets/SliceViewer/NonOrthogonalAxis.h"
 #include "MantidQtWidgets/SliceViewer/PeakOverlayInteractive.h"
@@ -121,5 +120,3 @@ private:
 };
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakViewColor.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakViewColor.h
index e1fe062a2ea8b537197a27f311a03f892313aa9e..d2740f6c6ec2c18f7fea5bd95180b237ebbc764c 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakViewColor.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakViewColor.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_PEAK_VIEW_COLOR_H_
-#define MANTID_SLICEVIEWER_PEAK_VIEW_COLOR_H_
+#pragma once
 
 #include <QColor>
 
@@ -44,5 +43,3 @@ struct PeakViewColor {
   QColor colorSphere;
   QColor colorEllipsoid;
 };
-
-#endif
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakViewFactory.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakViewFactory.h
index 1609d831b29a91ab2d9673ac8657e26b661bc836..5e5799d23bcf5d3f57f6a7ba2e9a51c06d91ce61 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakViewFactory.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeakViewFactory.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_PEAK_VIEW_FACTORY_H_
-#define MANTID_SLICEVIEWER_PEAK_VIEW_FACTORY_H_
+#pragma once
 
 #include "MantidAPI/IMDWorkspace.h"
 #include "MantidAPI/IPeaksWorkspace.h"
@@ -79,5 +78,3 @@ private:
 };
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeaksPresenter.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeaksPresenter.h
index b454d771176fd1e06d6861a86779912c81c7b7a1..7ba22e4ae0b6d3a203294f30edb22867d04a6f27 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeaksPresenter.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeaksPresenter.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_PEAKSPRESENTER_H_
-#define MANTID_SLICEVIEWER_PEAKSPRESENTER_H_
+#pragma once
 
 #include "DllOption.h"
 #include "MantidQtWidgets/SliceViewer/PeakBoundingBox.h"
@@ -91,5 +90,3 @@ using PeaksPresenter_sptr = boost::shared_ptr<PeaksPresenter>;
 using PeaksPresenter_const_sptr = boost::shared_ptr<const PeaksPresenter>;
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif /* MANTID_SLICEVIEWER_PEAKSPRESENTER_H_ */
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeaksTableColumnsDialog.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeaksTableColumnsDialog.h
index 5e6cc73fa36349be5ec899ffe4be4fe8ac43075a..2ef424605862e8207f0f842323c37b27a73b392f 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeaksTableColumnsDialog.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeaksTableColumnsDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef PEAKSTABLECOLUMNSDIALOG_H
-#define PEAKSTABLECOLUMNSDIALOG_H
+#pragma once
 
 #include <QDialog>
 #include <set>
@@ -34,5 +33,3 @@ private:
 
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif // PEAKSTABLECOLUMNSDIALOG_H
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeaksViewer.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeaksViewer.h
index f6f93f1cd1f86d7a80c7e6d11966fe1e6195ed77..45b9303e24ded9c3f591955e260816bc0ceb6ec0 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeaksViewer.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeaksViewer.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef PEAKSVIEWER_H
-#define PEAKSVIEWER_H
+#pragma once
 
 #include "DllOption.h"
 #include "MantidAPI/IPeaksWorkspace_fwd.h"
@@ -93,5 +92,4 @@ private:
 };
 
 } // namespace SliceViewer
-} // namespace MantidQt
-#endif // PEAKSVIEWER_H
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeaksViewerOverlayDialog.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeaksViewerOverlayDialog.h
index 772620a348843a94f11a904cec66c5359c483600..793d25046de4fbbd0bea683b9e86fb767a8ddc52 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeaksViewerOverlayDialog.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeaksViewerOverlayDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDSLICEVIEWER_PEAKSVIEWEROVERLAYDIALOG_H
-#define MANTIDSLICEVIEWER_PEAKSVIEWEROVERLAYDIALOG_H
+#pragma once
 
 #include "MantidQtWidgets/SliceViewer/PeaksPresenter.h"
 #include <QDialog>
@@ -45,5 +44,3 @@ private:
 };
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif // MANTIDSLICEVIEWER_PEAKSVIEWEROVERLAYDIALOG_H
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeaksWorkspaceWidget.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeaksWorkspaceWidget.h
index a1635fa149550147ebfa396b8166ca1f5e466003..0051e201fe3396303dec1a4a43f3347da0c3cbea 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeaksWorkspaceWidget.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/PeaksWorkspaceWidget.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef PEAKSWORKSPACEWIDGET_H
-#define PEAKSWORKSPACEWIDGET_H
+#pragma once
 
 #include "DllOption.h"
 #include "MantidAPI/IPeaksWorkspace_fwd.h"
@@ -102,5 +101,4 @@ private slots:
 };
 
 } // namespace SliceViewer
-} // namespace MantidQt
-#endif // PEAKSWORKSPACEWIDGET_H
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/ProxyCompositePeaksPresenter.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/ProxyCompositePeaksPresenter.h
index 5ff62a12fce70bf6c42d178afa45f56f4750487a..a4179d76c8c3b7fc4d24f24c389691999167cfb7 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/ProxyCompositePeaksPresenter.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/ProxyCompositePeaksPresenter.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_PROXYCOMPOSITEPEAKSPRESENTER_H_
-#define MANTID_SLICEVIEWER_PROXYCOMPOSITEPEAKSPRESENTER_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 #include "MantidQtWidgets/SliceViewer/CompositePeaksPresenter.h"
@@ -107,5 +106,3 @@ private:
 };
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/QwtScaleDrawNonOrthogonal.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/QwtScaleDrawNonOrthogonal.h
index 89db433075b5b0d2d43a5159af17923f1fb2139a..755ac9bdb1e3f313751ff64f5c2af8cb4d528ca2 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/QwtScaleDrawNonOrthogonal.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/QwtScaleDrawNonOrthogonal.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef QWT_SCALE_DRAW_NON_ORTHOGONAL_H
-#define QWT_SCALE_DRAW_NON_ORTHOGONAL_H
+#pragma once
 
 #include "MantidAPI/IMDWorkspace.h"
 #include "MantidGeometry/MDGeometry/MDTypes.h"
@@ -65,5 +64,3 @@ private:
   double m_angleY;
   MantidQt::SliceViewer::NonOrthogonalOverlay *m_gridPlot;
 };
-
-#endif
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/SliceViewer.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/SliceViewer.h
index 14cdfd783542c476e1785c9ca4bf41c77f9cb491..3b66df3d5d3c14d9a879b5d2001ea6ba1ee00dc1 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/SliceViewer.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/SliceViewer.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SLICEVIEWER_H
-#define SLICEVIEWER_H
+#pragma once
 
 #include "DimensionSliceWidget.h"
 #include "DllOption.h"
@@ -436,5 +435,3 @@ private:
 
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif // SLICEVIEWER_H
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/SliceViewerFunctions.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/SliceViewerFunctions.h
index 6ff3edf70cd883ee203a25107f3a9e3d713f4856..62bf681919e10842ae127c2c826cb219e4d25323 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/SliceViewerFunctions.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/SliceViewerFunctions.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SLICEVIEWER_FUNCTIONS_H
-#define SLICEVIEWER_FUNCTIONS_H
+#pragma once
 
 #include "DllOption.h"
 #include "MantidAPI/IMDWorkspace.h"
@@ -28,5 +27,4 @@ bool EXPORT_OPT_MANTIDQT_SLICEVIEWER isRebinInConsistentState(
 bool EXPORT_OPT_MANTIDQT_SLICEVIEWER shouldAutoScaleForNewlySetWorkspace(
     bool isFirstWorkspaceOpen, bool isAutoScalingOnLoad);
 } // namespace SliceViewer
-} // namespace MantidQt
-#endif
+} // namespace MantidQt
\ No newline at end of file
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/SliceViewerWindow.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/SliceViewerWindow.h
index 91d35ddacb6fe1f48ad0cdd5036c026f5988446e..b78e3bcad6a5d462a95734edbbef51c1e856e917 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/SliceViewerWindow.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/SliceViewerWindow.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SLICEVIEWERWINDOW_H
-#define SLICEVIEWERWINDOW_H
+#pragma once
 
 #include "DllOption.h"
 #include "MantidAPI/IMDWorkspace.h"
@@ -122,5 +121,3 @@ protected:
 
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif // SLICEVIEWERWINDOW_H
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/SnapToGridDialog.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/SnapToGridDialog.h
index b5a837670bbc2ae42fa45f4985f4be57b8521742..68e34555d6f6509509233847e2fb95ea49360c77 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/SnapToGridDialog.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/SnapToGridDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SNAPTOGRIDDIALOG_H
-#define SNAPTOGRIDDIALOG_H
+#pragma once
 
 #include "DllOption.h"
 #include "ui_SnapToGridDialog.h"
@@ -31,5 +30,3 @@ public:
 private:
   Ui::SnapToGridDialogClass ui;
 };
-
-#endif // SNAPTOGRIDDIALOG_H
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/UpdateableOnDemand.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/UpdateableOnDemand.h
index ee89827e346e11743e17acb99641b7bbf90309e4..785b7fa76d430ef39d60d9efab26d87e15a6d537 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/UpdateableOnDemand.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/UpdateableOnDemand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef UPDATEABLEONDEMAND_H_
-#define UPDATEABLEONDEMAND_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 #include <boost/shared_ptr.hpp>
@@ -35,5 +34,3 @@ public:
 };
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif /* UPDATEABLEONDEMAND_H_ */
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/XYLimitsDialog.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/XYLimitsDialog.h
index 03e9f23d2f27dc1e4075d769c7a25de5df6a735f..68c01fa980e1608bb40861f440f9296a8fd6a7d0 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/XYLimitsDialog.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/XYLimitsDialog.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef XYLIMITSDIALOG_H
-#define XYLIMITSDIALOG_H
+#pragma once
 
 #include "DllOption.h"
 #include "MantidGeometry/MDGeometry/IMDDimension.h"
@@ -35,5 +34,3 @@ public:
 private:
   Ui::XYLimitsDialogClass ui;
 };
-
-#endif // XYLIMITSDIALOG_H
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/ZoomableOnDemand.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/ZoomableOnDemand.h
index be8951d21ed9a4387093369e655a8a7af3313d65..a11e570e63496098151f4c187e669644beac0323 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/ZoomableOnDemand.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/ZoomableOnDemand.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef ZOOMABLEONDEMAND_H_
-#define ZOOMABLEONDEMAND_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 
@@ -31,5 +30,3 @@ public:
 };
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif /* ZOOMABLEONDEMAND_H_ */
diff --git a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/ZoomablePeaksView.h b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/ZoomablePeaksView.h
index 990263a1c7bdc6b62db93c605dcab0d9803618d8..e3e6e6b7ed6e485c898b256b8faa8637e54afe8d 100644
--- a/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/ZoomablePeaksView.h
+++ b/qt/widgets/sliceviewer/inc/MantidQtWidgets/SliceViewer/ZoomablePeaksView.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTID_SLICEVIEWER_ZOOMABLE_PEAKS_VIEW_H_
-#define MANTID_SLICEVIEWER_ZOOMABLE_PEAKS_VIEW_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 #include "MantidKernel/V2D.h"
@@ -34,5 +33,3 @@ public:
 };
 } // namespace SliceViewer
 } // namespace MantidQt
-
-#endif /* MANTID_SLICEVIEWER_ZOOMABLE_PEAKS_VIEW_H_ */
diff --git a/qt/widgets/sliceviewer/test/CompositePeaksPresenterTest.h b/qt/widgets/sliceviewer/test/CompositePeaksPresenterTest.h
index 67f05531ceede15035ce820c15809ce5e3f38e1a..6df4a9a06f8530decf3054068a5fe513e6c15058 100644
--- a/qt/widgets/sliceviewer/test/CompositePeaksPresenterTest.h
+++ b/qt/widgets/sliceviewer/test/CompositePeaksPresenterTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SLICE_VIEWER_COMPOSITEPEAKSPRESENTER_TEST_H_
-#define SLICE_VIEWER_COMPOSITEPEAKSPRESENTER_TEST_H_
+#pragma once
 
 #include "MantidAPI/AnalysisDataService.h"
 #include "MantidDataObjects/PeaksWorkspace.h"
@@ -1070,5 +1069,3 @@ public:
     TS_ASSERT(Mock::VerifyAndClearExpectations(pSubjectB));
   }
 };
-
-#endif
diff --git a/qt/widgets/sliceviewer/test/ConcretePeaksPresenterTest.h b/qt/widgets/sliceviewer/test/ConcretePeaksPresenterTest.h
index 89acc3faf87f4c930e08b800602cbdd4f8295714..9eafeaf3903fa3df39a3ce091e472dbb12a3eff3 100644
--- a/qt/widgets/sliceviewer/test/ConcretePeaksPresenterTest.h
+++ b/qt/widgets/sliceviewer/test/ConcretePeaksPresenterTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SLICE_VIEWER_PEAKS_PRESENTER_TEST_H_
-#define SLICE_VIEWER_PEAKS_PRESENTER_TEST_H_
+#pragma once
 
 #include "MantidAPI/ExperimentInfo.h"
 #include "MantidAPI/FrameworkManager.h"
@@ -880,5 +879,3 @@ public:
     TSM_ASSERT_EQUALS("One peaks should remain", 1, peaksWS->getNumberPeaks());
   }
 };
-
-#endif
diff --git a/qt/widgets/sliceviewer/test/CoordinateTransformTest.h b/qt/widgets/sliceviewer/test/CoordinateTransformTest.h
index fe1cf160fa964178e73cffcbab628cf4d382c8b8..c9733ca942fd989fd1eb369d280a6d686934bc77 100644
--- a/qt/widgets/sliceviewer/test/CoordinateTransformTest.h
+++ b/qt/widgets/sliceviewer/test/CoordinateTransformTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_SLICEVIEWER_COORDINATETRANSFORM_TEST_H
-#define MANTIDQT_SLICEVIEWER_COORDINATETRANSFORM_TEST_H
+#pragma once
 
 #include "MantidAPI/AlgorithmManager.h"
 #include "MantidAPI/ExperimentInfo.h"
@@ -263,5 +262,4 @@ public:
                dynamic_cast<MantidQt::SliceViewer::NonOrthogonalTransform *>(
                    m_coordinateTransform.get()));
   }
-};
-#endif
+};
\ No newline at end of file
diff --git a/qt/widgets/sliceviewer/test/EllipsoidPlaneSliceCalculatorTest.h b/qt/widgets/sliceviewer/test/EllipsoidPlaneSliceCalculatorTest.h
index cbb82e7fd5905505272d8267b4473d495ccbb294..56fcd86de3c9b1f4c8157a023a491362a279cfe6 100644
--- a/qt/widgets/sliceviewer/test/EllipsoidPlaneSliceCalculatorTest.h
+++ b/qt/widgets/sliceviewer/test/EllipsoidPlaneSliceCalculatorTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SLICE_VIEWER_ELLIPSOID_PLANE_SLICE_CALCULATOR_TEST_H_
-#define SLICE_VIEWER_ELLIPSOID_PLANE_SLICE_CALCULATOR_TEST_H_
+#pragma once
 
 #include "MantidKernel/Matrix.h"
 #include "MantidKernel/V3D.h"
@@ -637,5 +636,3 @@ private:
                      info.origin.Z(), 1.5, delta);
   }
 };
-
-#endif
diff --git a/qt/widgets/sliceviewer/test/MockObjects.h b/qt/widgets/sliceviewer/test/MockObjects.h
index 67e19e6eef463d8608faed1bec17145cd17f8a7d..d22b07db82b902ec80c51f02a3915553f35c4879 100644
--- a/qt/widgets/sliceviewer/test/MockObjects.h
+++ b/qt/widgets/sliceviewer/test/MockObjects.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SLICE_VIEWER_MOCKOBJECTS_H_
-#define SLICE_VIEWER_MOCKOBJECTS_H_
+#pragma once
 
 #include "MantidAPI/IMDWorkspace.h"
 #include "MantidAPI/IPeaksWorkspace.h"
@@ -204,5 +203,3 @@ public:
 } // namespace
 
 GNU_DIAG_ON_SUGGEST_OVERRIDE
-
-#endif
diff --git a/qt/widgets/sliceviewer/test/NullPeaksPresenterTest.h b/qt/widgets/sliceviewer/test/NullPeaksPresenterTest.h
index c82079c029d945fab8c90c10767b78f0b22145f3..e4aff1d7c42b541397628e65759ead4f62d0bf32 100644
--- a/qt/widgets/sliceviewer/test/NullPeaksPresenterTest.h
+++ b/qt/widgets/sliceviewer/test/NullPeaksPresenterTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SLICE_VIEWER_NULLPEAKSPRESENTER_TEST_H_
-#define SLICE_VIEWER_NULLPEAKSPRESENTER_TEST_H_
+#pragma once
 
 #include "MantidQtWidgets/SliceViewer/NullPeaksPresenter.h"
 #include "MockObjects.h"
@@ -119,5 +118,3 @@ public:
     TS_ASSERT_THROWS_NOTHING(presenter.deletePeaksIn(fake));
   }
 };
-
-#endif
diff --git a/qt/widgets/sliceviewer/test/PeakBoundingBoxTest.h b/qt/widgets/sliceviewer/test/PeakBoundingBoxTest.h
index 83a25e69fbd548d4886e59b429b9cf70c56b089e..bf0e69cfa52e39f59254dc4d996e733fb8dfb8eb 100644
--- a/qt/widgets/sliceviewer/test/PeakBoundingBoxTest.h
+++ b/qt/widgets/sliceviewer/test/PeakBoundingBoxTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SLICE_VIEWER_PEAKBOUNDINGBOX_TEST_H_
-#define SLICE_VIEWER_PEAKBOUNDINGBOX_TEST_H_
+#pragma once
 
 #include "MantidQtWidgets/SliceViewer/PeakBoundingBox.h"
 #include <cxxtest/TestSuite.h>
@@ -202,5 +201,3 @@ public:
     TS_ASSERT_EQUALS("-1.23,1.23,-20.23,2.23,3.12,4.12", extents);
   }
 };
-
-#endif
diff --git a/qt/widgets/sliceviewer/test/PeakPaletteTest.h b/qt/widgets/sliceviewer/test/PeakPaletteTest.h
index 47256d1a6a9ccc7d89f1e8bec70319645788555b..92f6ddf0123b6009877ed03198e31490b944df0a 100644
--- a/qt/widgets/sliceviewer/test/PeakPaletteTest.h
+++ b/qt/widgets/sliceviewer/test/PeakPaletteTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SLICE_VIEWER_PEAKPALETTE_TEST_H_
-#define SLICE_VIEWER_PEAKPALETTE_TEST_H_
+#pragma once
 
 #include "MantidQtWidgets/SliceViewer/PeakPalette.h"
 #include <cxxtest/TestSuite.h>
@@ -268,5 +267,3 @@ public:
                                   palette.backgroundIndexToColour(index));
   }
 };
-
-#endif
diff --git a/qt/widgets/sliceviewer/test/PeakRepresentationCrossTest.h b/qt/widgets/sliceviewer/test/PeakRepresentationCrossTest.h
index ee1159de1130036bfcda0b1d00895017ad5001b8..bf4bbc19ae4671e4b2a97581454ab93db465ef91 100644
--- a/qt/widgets/sliceviewer/test/PeakRepresentationCrossTest.h
+++ b/qt/widgets/sliceviewer/test/PeakRepresentationCrossTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SLICE_VIEWER_PEAK_REPRESENTATION_CROSS_TEST_H_
-#define SLICE_VIEWER_PEAK_REPRESENTATION_CROSS_TEST_H_
+#pragma once
 
 #include "MantidQtWidgets/SliceViewer/PeakRepresentationCross.h"
 #include "MockObjects.h"
@@ -279,5 +278,3 @@ public:
     }
   }
 };
-
-#endif
diff --git a/qt/widgets/sliceviewer/test/PeakRepresentationEllipsoidTest.h b/qt/widgets/sliceviewer/test/PeakRepresentationEllipsoidTest.h
index 15c8701db423d2388b16ed569b81d48cc34d1987..256bdd4e9594a23ebee742bd25387491ed41713b 100644
--- a/qt/widgets/sliceviewer/test/PeakRepresentationEllipsoidTest.h
+++ b/qt/widgets/sliceviewer/test/PeakRepresentationEllipsoidTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SLICE_VIEWER_PEAK_REPRESENTATION_CROSS_TEST_H_
-#define SLICE_VIEWER_PEAK_REPRESENTATION_CROSS_TEST_H_
+#pragma once
 
 #include "MantidQtWidgets/SliceViewer/PeakRepresentationEllipsoid.h"
 #include "MockObjects.h"
@@ -225,5 +224,3 @@ private:
         directions, calculator);
   }
 };
-
-#endif
diff --git a/qt/widgets/sliceviewer/test/PeakRepresentationSphereTest.h b/qt/widgets/sliceviewer/test/PeakRepresentationSphereTest.h
index c96855c99980f669f6dab86d5e4193567a2b006a..422f75f341a38a030765cb9aa3a75e9286d89ca4 100644
--- a/qt/widgets/sliceviewer/test/PeakRepresentationSphereTest.h
+++ b/qt/widgets/sliceviewer/test/PeakRepresentationSphereTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SLICE_VIEWER_PEAK_REPRESENTATION_SPHERE_TEST_H_
-#define SLICE_VIEWER_PEAK_REPRESENTATION_SPHERE_TEST_H_
+#pragma once
 
 #include "MantidQtWidgets/SliceViewer/PeakRepresentationSphere.h"
 #include "MockObjects.h"
@@ -331,5 +330,3 @@ private:
   VecPeaksRepresentationSphere m_peaks;
   PeakRepresentationViewInformation m_viewInformation;
 };
-
-#endif
diff --git a/qt/widgets/sliceviewer/test/SliceViewerFunctionsTest.h b/qt/widgets/sliceviewer/test/SliceViewerFunctionsTest.h
index f82ed6ff9af95e620d7461ccda6e8c8ae1936e03..b966b3e21100c788a417986aeacd10c3f0407dbb 100644
--- a/qt/widgets/sliceviewer/test/SliceViewerFunctionsTest.h
+++ b/qt/widgets/sliceviewer/test/SliceViewerFunctionsTest.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SLICE_VIEWER_SLICE_VIEWER_FUNCTIONS_TEST_H_
-#define SLICE_VIEWER_SLICE_VIEWER_FUNCTIONS_TEST_H_
+#pragma once
 
 #include "MantidGeometry/MDGeometry/GeneralFrame.h"
 #include "MantidGeometry/MDGeometry/MDHistoDimension.h"
@@ -119,6 +118,4 @@ public:
   }
 };
 
-#endif
-
 // end SLICE_VIEWER_SLICE_VIEWER_FUNCTIONS_TEST_H_
diff --git a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/ArrayDataSource.h b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/ArrayDataSource.h
index 2a6cfabd3282c0dd527316677359faa2d7c70316..9a125a5e001797dc7be1cd339fc1d805e5b49790 100644
--- a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/ArrayDataSource.h
+++ b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/ArrayDataSource.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef ARRAY_DATA_SOURCE_H
-#define ARRAY_DATA_SOURCE_H
+#pragma once
 
 #include "MantidQtWidgets/SpectrumViewer/DataArray.h"
 #include "MantidQtWidgets/SpectrumViewer/SpectrumDataSource.h"
@@ -58,5 +57,3 @@ using ArrayDataSource_const_sptr = boost::shared_ptr<const ArrayDataSource>;
 
 } // namespace SpectrumView
 } // namespace MantidQt
-
-#endif // ARRAY_DATA_SOURCE_H
diff --git a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/ColorMaps.h b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/ColorMaps.h
index 9d554a2bdc29b76260b0efb47cb038d86a8bb4b1..0edd9c54ef04924da3c4e8040620bb5d19ef78fe 100644
--- a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/ColorMaps.h
+++ b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/ColorMaps.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef COLOR_MAPS_H
-#define COLOR_MAPS_H
+#pragma once
 
 #include "MantidQtWidgets/SpectrumViewer/DllOptionSV.h"
 #include <QColor>
@@ -57,5 +56,3 @@ private:
 
 } // namespace SpectrumView
 } // namespace MantidQt
-
-#endif // COLOR_MAPS_H
diff --git a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/DataArray.h b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/DataArray.h
index dcd9f508b2691578d6a5be48792a0f73da789c2c..bd425b050b048496027ffa44f3b3cb98384e62ca 100644
--- a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/DataArray.h
+++ b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/DataArray.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef DATA_ARRAY_H
-#define DATA_ARRAY_H
+#pragma once
 
 #include <cstddef>
 #include <vector>
@@ -115,5 +114,3 @@ using DataArray_const_sptr = boost::shared_ptr<const DataArray>;
 
 } // namespace SpectrumView
 } // namespace MantidQt
-
-#endif // DATA_ARRAY_H
diff --git a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/DllOptionSV.h b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/DllOptionSV.h
index 586025502866154e09e4ca82488091ca50d98963..d8a2b568ec8a458db898a6c1211c70f87b35106d 100644
--- a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/DllOptionSV.h
+++ b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/DllOptionSV.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MANTIDQT_MANTID_SPECTRUM_VIEWER_DLLOPTION_H_
-#define MANTIDQT_MANTID_SPECTRUM_VIEWER_DLLOPTION_H_
+#pragma once
 
 #include "MantidKernel/System.h"
 
@@ -14,5 +13,3 @@
 #else
 #define EXPORT_OPT_MANTIDQT_SPECTRUMVIEWER DLLImport
 #endif
-
-#endif // MANTIDQT_MANTID_SPECTRUM_VIEWER_DLLOPTION_H_
diff --git a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/EModeHandler.h b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/EModeHandler.h
index 79755c9028a9568d744d616b874c963808274f67..f2ae2a13d7c9b3bb61d390be979a3cdecfb8c812 100644
--- a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/EModeHandler.h
+++ b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/EModeHandler.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef EMODE_HANDLER_H
-#define EMODE_HANDLER_H
+#pragma once
 
 #include "MantidQtWidgets/SpectrumViewer/DllOptionSV.h"
 #include "MantidQtWidgets/SpectrumViewer/SpectrumDataSource.h"
@@ -47,5 +46,3 @@ private:
 
 } // namespace SpectrumView
 } // namespace MantidQt
-
-#endif // EMODE_HANDLER_H
diff --git a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/GraphDisplay.h b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/GraphDisplay.h
index f99a65b4564e96b3420a85eb21b6206160db3e60..66f03b6f100f7ca6436e56e23e35f840b6d1d545 100644
--- a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/GraphDisplay.h
+++ b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/GraphDisplay.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef GRAPH_DISPLAY_H
-#define GRAPH_DISPLAY_H
+#pragma once
 
 #include <QTableWidget>
 #include <qwt_plot.h>
@@ -83,5 +82,3 @@ private:
 
 } // namespace SpectrumView
 } // namespace MantidQt
-
-#endif // GRAPH_DISPLAY_H
diff --git a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/IRangeHandler.h b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/IRangeHandler.h
index d078778ca5d464f594d76006a5cab6ae4813da8b..db48664f9524bc48ed01656938333dd09fc8ec74 100644
--- a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/IRangeHandler.h
+++ b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/IRangeHandler.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef IRANGE_HANDLER_H
-#define IRANGE_HANDLER_H
+#pragma once
 
 #include "MantidQtWidgets/SpectrumViewer/DllOptionSV.h"
 #include "MantidQtWidgets/SpectrumViewer/SpectrumDataSource.h"
@@ -33,5 +32,3 @@ public:
 
 } // namespace SpectrumView
 } // namespace MantidQt
-
-#endif // IRANGE_HANDLER_H
diff --git a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/ISliderHandler.h b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/ISliderHandler.h
index 101917f638fe2220b09b21e2f8d10a9898dccbd6..e3113db137613d6214cd1cd934b3ff1d5bd9e308 100644
--- a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/ISliderHandler.h
+++ b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/ISliderHandler.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef ISLIDER_HANDLER_H
-#define ISLIDER_HANDLER_H
+#pragma once
 
 #include "MantidQtWidgets/SpectrumViewer/DllOptionSV.h"
 #include "MantidQtWidgets/SpectrumViewer/SpectrumDataSource.h"
@@ -47,5 +46,3 @@ public:
 
 } // namespace SpectrumView
 } // namespace MantidQt
-
-#endif // ISLIDER_HANDLER_H
diff --git a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/MatrixWSDataSource.h b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/MatrixWSDataSource.h
index a7db0ffc8a4556371f3be0503477f9086d061e84..c88b40cafdf5f0390f7a3b62fe5680353c995f04 100644
--- a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/MatrixWSDataSource.h
+++ b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/MatrixWSDataSource.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef MATRIX_WS_DATA_SOURCE_H
-#define MATRIX_WS_DATA_SOURCE_H
+#pragma once
 
 #include <cstddef>
 
@@ -95,5 +94,3 @@ using MatrixWSDataSource_const_sptr =
 
 } // namespace SpectrumView
 } // namespace MantidQt
-
-#endif // MATRIX_WS_DATA_SOURCE_H
diff --git a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/QtUtils.h b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/QtUtils.h
index c10c8143751d3fbc7536e9695ed2fb63b0409d12..fff6969183f2a57cc5c68574e307b40f00690aaf 100644
--- a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/QtUtils.h
+++ b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/QtUtils.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef QT_UTILS_H
-#define QT_UTILS_H
+#pragma once
 
 #include <QLineEdit>
 #include <QTableWidget>
@@ -45,5 +44,3 @@ public:
 
 } // namespace SpectrumView
 } // namespace MantidQt
-
-#endif // QT_UTILS_H
diff --git a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/RangeHandler.h b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/RangeHandler.h
index ab9f3dbbb7f67856e6a18fc39273f6f85303db08..8f1f8430e2175fcdf5439760c4773347e54f9a42 100644
--- a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/RangeHandler.h
+++ b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/RangeHandler.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef RANGE_HANDLER_H
-#define RANGE_HANDLER_H
+#pragma once
 
 #include "MantidQtWidgets/SpectrumViewer/DllOptionSV.h"
 #include "MantidQtWidgets/SpectrumViewer/IRangeHandler.h"
@@ -48,5 +47,3 @@ private:
 
 } // namespace SpectrumView
 } // namespace MantidQt
-
-#endif // RANGE_HANDLER_H
diff --git a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SVConnections.h b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SVConnections.h
index b1bfb6ee1861066da751a62c3d7b2315e2888c68..d34986ecd51369c246547a0657f2d7635b785652 100644
--- a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SVConnections.h
+++ b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SVConnections.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SV_CONNECTIONS_H
-#define SV_CONNECTIONS_H
+#pragma once
 
 #include <QActionGroup>
 #include <QWidget>
@@ -113,5 +112,3 @@ private:
 
 } // namespace SpectrumView
 } // namespace MantidQt
-
-#endif // SV_CONNECTIONS_H
diff --git a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SVUtils.h b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SVUtils.h
index 031972919b22e02e5ca367b721b2e87c66ddc4e8..3629759fefccf2dfbcbc6286f6602fa892b18587 100644
--- a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SVUtils.h
+++ b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SVUtils.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SV_UTILS_H
-#define SV_UTILS_H
+#pragma once
 
 #include <QVector>
 
@@ -66,5 +65,3 @@ public:
 
 } // namespace SpectrumView
 } // namespace MantidQt
-
-#endif // SV_UTILS_H
diff --git a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SliderHandler.h b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SliderHandler.h
index 4f1d7c8b78b276635b1e19b29df3ee4fa6959b90..b61c1f3fd45e196d5a952ddfa8dc7363562586b8 100644
--- a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SliderHandler.h
+++ b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SliderHandler.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SLIDER_HANDLER_H
-#define SLIDER_HANDLER_H
+#pragma once
 
 #include "MantidQtWidgets/SpectrumViewer/ISliderHandler.h"
 #include <QRect>
@@ -64,5 +63,3 @@ private:
 
 } // namespace SpectrumView
 } // namespace MantidQt
-
-#endif // SLIDER_HANDLER_H
diff --git a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SpectrumDataSource.h b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SpectrumDataSource.h
index 7755a9efac71ba8f8bf0968fe2cfd62cbd1c56d0..7b934f9a1e2b897370a31694a4c220d92bccca2c 100644
--- a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SpectrumDataSource.h
+++ b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SpectrumDataSource.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SPECTRUM_DATA_SOURCE_H
-#define SPECTRUM_DATA_SOURCE_H
+#pragma once
 
 #include "MantidAPI/Workspace_fwd.h"
 #include "MantidQtWidgets/SpectrumViewer/DataArray.h"
@@ -98,5 +97,3 @@ using SpectrumDataSource_const_sptr =
 
 } // namespace SpectrumView
 } // namespace MantidQt
-
-#endif // SPECTRUM_DATA_SOURCE_H
diff --git a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SpectrumDisplay.h b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SpectrumDisplay.h
index cebb5b3cc42d900c4054fd3f1e9b20cc941d9bea..211e8dbf77e7b176600731011b941e8458728cd4 100644
--- a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SpectrumDisplay.h
+++ b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SpectrumDisplay.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SPECTRUM_DISPLAY_H
-#define SPECTRUM_DISPLAY_H
+#pragma once
 
 #include <QColor>
 #include <QPoint>
@@ -158,5 +157,3 @@ private:
 
 } // namespace SpectrumView
 } // namespace MantidQt
-
-#endif // SPECTRUM_DISPLAY_H
diff --git a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SpectrumPlotItem.h b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SpectrumPlotItem.h
index eb939275353811976806ea316b2b364a26a03045..dfb9716a77649c9c92ba5a9c96c7d54432e61ef7 100644
--- a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SpectrumPlotItem.h
+++ b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SpectrumPlotItem.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SPECTRUM_PLOT_ITEM_H
-#define SPECTRUM_PLOT_ITEM_H
+#pragma once
 
 #include <QPainter>
 #include <QRect>
@@ -65,5 +64,3 @@ private:
 
 } // namespace SpectrumView
 } // namespace MantidQt
-
-#endif // SPECTRUM_PLOT_ITEM_H
diff --git a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SpectrumView.h b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SpectrumView.h
index c804f474debdd3802ababdbe7a84bff850113b0f..20f84f7399497d8a5d6012e55c7017aedcb4f4a4 100644
--- a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SpectrumView.h
+++ b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/SpectrumView.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef SPECTRUM_VIEW_H
-#define SPECTRUM_VIEW_H
+#pragma once
 
 #include <QList>
 #include <QMainWindow>
@@ -126,5 +125,3 @@ signals:
 
 } // namespace SpectrumView
 } // namespace MantidQt
-
-#endif // SPECTRUM_VIEW_H
diff --git a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/TrackingPicker.h b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/TrackingPicker.h
index cb3ce3bc3adfac3a63219199aaa95a479433f414..67ddf5f1db8fef7b2a77d9c7b23d762104601090 100644
--- a/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/TrackingPicker.h
+++ b/qt/widgets/spectrumviewer/inc/MantidQtWidgets/SpectrumViewer/TrackingPicker.h
@@ -4,8 +4,7 @@
 //     NScD Oak Ridge National Laboratory, European Spallation Source
 //     & Institut Laue - Langevin
 // SPDX - License - Identifier: GPL - 3.0 +
-#ifndef TRACKING_PICKER_H
-#define TRACKING_PICKER_H
+#pragma once
 
 #include "MantidQtWidgets/SpectrumViewer/DllOptionSV.h"
 #include <qwt_plot_canvas.h>
@@ -51,5 +50,3 @@ private:
 
 } // namespace SpectrumView
 } // namespace MantidQt
-
-#endif // TRACKING_PICKER_H