diff --git a/Framework/HistogramData/inc/MantidHistogramData/FixedLengthVector.h b/Framework/HistogramData/inc/MantidHistogramData/FixedLengthVector.h
index 53cb5f7dc9b564ea7f6104a00a589ad8651e1c46..76c0a60cfe4dc817702e23600dfeb0f23361b8d3 100644
--- a/Framework/HistogramData/inc/MantidHistogramData/FixedLengthVector.h
+++ b/Framework/HistogramData/inc/MantidHistogramData/FixedLengthVector.h
@@ -109,6 +109,10 @@ public:
     return this->rawData() == rhs.rawData();
   }
 
+  bool operator!=(const FixedLengthVector<T> &rhs) const {
+    return !(*this == rhs);
+  }
+
   bool empty() const { return m_data.empty(); }
   size_t size() const { return m_data.size(); }