diff --git a/Framework/Crystal/src/SaveIsawPeaks.cpp b/Framework/Crystal/src/SaveIsawPeaks.cpp
index ebccb80a5f28b8d86f3863d2d911e51d5a979a85..3462324873ee4bc4fe472f0f7bb06698e2a14fc9 100644
--- a/Framework/Crystal/src/SaveIsawPeaks.cpp
+++ b/Framework/Crystal/src/SaveIsawPeaks.cpp
@@ -267,7 +267,8 @@ void SaveIsawPeaks::exec() {
   runMap_t::iterator runMap_it;
   for (runMap_it = runMap.begin(); runMap_it != runMap.end(); ++runMap_it) {
     // Start of a new run
-    if (maxPeakNumb > 0) appendPeakNumb += maxPeakNumb + 1;
+    if (maxPeakNumb > 0)
+      appendPeakNumb += maxPeakNumb + 1;
     int run = runMap_it->first;
     bankMap_t &bankMap = runMap_it->second;
 
diff --git a/docs/source/release/v3.14.0/diffraction.rst b/docs/source/release/v3.14.0/diffraction.rst
index 2fcddad7d3add66de7a34d014425e33b37d051b6..a014567f662226dd49a00f0b28b29aa2c97639c3 100644
--- a/docs/source/release/v3.14.0/diffraction.rst
+++ b/docs/source/release/v3.14.0/diffraction.rst
@@ -41,6 +41,7 @@ Bugfixes
 - :ref:`CentroidPeaksMD <algm-CentroidPeaksMD>` now updates peak bin counts.
 
 - :ref:`FindPeaksMD <algm-FindPeaksMD>` now finds peaks correctly with the crystallography convention setting and reduction with crystallography convention is tested with a system test.
+- :ref:`SaveIsawPeaks <algm-SaveIsawPeaks>` does not have duplicate peak numbers when saving PeaksWorkspaces with more than one RunNumber.
 
 Powder Diffraction
 ------------------