diff --git a/src/openrct2/config/IniReader.hpp b/src/openrct2/config/IniReader.hpp
index ff01b20e15..9b47c5f557 100644
--- a/src/openrct2/config/IniReader.hpp
+++ b/src/openrct2/config/IniReader.hpp
@@ -14,6 +14,8 @@
  *****************************************************************************/
 #pragma endregion
 
+#pragma once
+
 #include <string>
 #include "../common.h"
 #include "ConfigEnum.hpp"
diff --git a/src/openrct2/config/IniWriter.hpp b/src/openrct2/config/IniWriter.hpp
index 31f2d5a01a..05f002d2a5 100644
--- a/src/openrct2/config/IniWriter.hpp
+++ b/src/openrct2/config/IniWriter.hpp
@@ -14,6 +14,8 @@
  *****************************************************************************/
 #pragma endregion
 
+#pragma once
+
 #include <string>
 #include "../common.h"
 #include "ConfigEnum.hpp"
diff --git a/src/openrct2/paint/Painter.h b/src/openrct2/paint/Painter.h
index b5ba727d7f..244193cb0e 100644
--- a/src/openrct2/paint/Painter.h
+++ b/src/openrct2/paint/Painter.h
@@ -14,6 +14,8 @@
  *****************************************************************************/
 #pragma endregion
 
+#pragma once
+
 #ifdef __cplusplus
 
 #include <ctime>
diff --git a/src/openrct2/ride/coaster/BolligerMabillardTrack.h b/src/openrct2/ride/coaster/BolligerMabillardTrack.h
index 9f24fbe335..6b214da5f4 100644
--- a/src/openrct2/ride/coaster/BolligerMabillardTrack.h
+++ b/src/openrct2/ride/coaster/BolligerMabillardTrack.h
@@ -14,6 +14,8 @@
  *****************************************************************************/
 #pragma endregion
 
+#pragma once
+
 void bolliger_mabillard_track_flat(paint_session * session, uint8 rideIndex, uint8 trackSequence, uint8 direction, sint32 height, rct_tile_element * tileElement, sint32 supportType);
 void bolliger_mabillard_track_station(paint_session * session, uint8 rideIndex, uint8 trackSequence, uint8 direction, sint32 height, rct_tile_element * tileElement, sint32 supportType);
 void bolliger_mabillard_track_25_deg_up(paint_session * session, uint8 rideIndex, uint8 trackSequence, uint8 direction, sint32 height, rct_tile_element * tileElement, sint32 supportType);