diff --git a/src/slic3r/GUI/GUI_ObjectManipulation.cpp b/src/slic3r/GUI/GUI_ObjectManipulation.cpp
index 7d9a87b588..02ef719f14 100644
--- a/src/slic3r/GUI/GUI_ObjectManipulation.cpp
+++ b/src/slic3r/GUI/GUI_ObjectManipulation.cpp
@@ -1,5 +1,6 @@
 #include "GUI_ObjectManipulation.hpp"
 #include "I18N.hpp"
+#include "format.hpp"
 #include "BitmapComboBox.hpp"
 
 #include "GLCanvas3D.hpp"
diff --git a/src/slic3r/GUI/GUI_ObjectSettings.cpp b/src/slic3r/GUI/GUI_ObjectSettings.cpp
index 41cad87921..a6d85cef71 100644
--- a/src/slic3r/GUI/GUI_ObjectSettings.cpp
+++ b/src/slic3r/GUI/GUI_ObjectSettings.cpp
@@ -12,6 +12,7 @@
 #include <boost/algorithm/string.hpp>
 
 #include "I18N.hpp"
+#include "format.hpp"
 #include "ConfigManipulation.hpp"
 
 #include <wx/wupdlock.h>