diff --git a/include/canvas/elapsedtime.hxx b/include/canvas/elapsedtime.hxx
index cf73af960eb1..e8ee396d92e2 100644
--- a/include/canvas/elapsedtime.hxx
+++ b/include/canvas/elapsedtime.hxx
@@ -17,8 +17,7 @@
  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  */
 
-#ifndef INCLUDED_CANVAS_ELAPSEDTIME_HXX
-#define INCLUDED_CANVAS_ELAPSEDTIME_HXX
+#pragma once
 
 #include <canvas/canvastoolsdllapi.h>
 #include <memory>
@@ -158,6 +157,4 @@ namespace canvas::tools
 
 }
 
-#endif /* INCLUDED_CANVAS_ELAPSEDTIME_HXX */
-
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/include/drawinglayer/XShapeDumper.hxx b/include/drawinglayer/XShapeDumper.hxx
index 47f5b0c26e88..e54bf70f6df7 100644
--- a/include/drawinglayer/XShapeDumper.hxx
+++ b/include/drawinglayer/XShapeDumper.hxx
@@ -7,8 +7,7 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
  */
 
-#ifndef INCLUDED_DRAWINGLAYER_XSHAPEDUMPER_HXX
-#define INCLUDED_DRAWINGLAYER_XSHAPEDUMPER_HXX
+#pragma once
 
 #include <drawinglayer/drawinglayerdllapi.h>
 #include <rtl/ustring.hxx>
@@ -24,6 +23,4 @@ struct DRAWINGLAYER_DLLPUBLIC XShapeDumper
     static OUString dump(const css::uno::Reference<css::drawing::XShape>& xPageShapes, bool bDumpInteropProperties=false);
 };
 
-#endif
-
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/include/drawinglayer/drawinglayerdllapi.h b/include/drawinglayer/drawinglayerdllapi.h
index 36a0d8abfea2..d39b857ff479 100644
--- a/include/drawinglayer/drawinglayerdllapi.h
+++ b/include/drawinglayer/drawinglayerdllapi.h
@@ -7,8 +7,7 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
  */
 
-#ifndef INCLUDED_DRAWINGLAYER_DRAWINGLAYERDLLAPI_H
-#define INCLUDED_DRAWINGLAYER_DRAWINGLAYERDLLAPI_H
+#pragma once
 
 #include <sal/types.h>
 
@@ -25,6 +24,4 @@
 #define DRAWINGLAYERCORE_DLLPUBLIC SAL_DLLPUBLIC_IMPORT
 #endif
 
-#endif
-
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/stoc/source/implementationregistration/mergekeys.hxx b/stoc/source/implementationregistration/mergekeys.hxx
index 3f54e571241f..34584bdab30e 100644
--- a/stoc/source/implementationregistration/mergekeys.hxx
+++ b/stoc/source/implementationregistration/mergekeys.hxx
@@ -17,8 +17,7 @@
  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  */
 
-#ifndef INCLUDED_STOC_SOURCE_IMPLEMENTATIONREGISTRATION_MERGEKEYS_HXX
-#define INCLUDED_STOC_SOURCE_IMPLEMENTATIONREGISTRATION_MERGEKEYS_HXX
+#pragma once
 
 #include <sal/config.h>
 #include <sal/types.h>
@@ -41,6 +40,4 @@ void mergeKeys(
 
 }
 
-#endif
-
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */