diff --git a/src/univ/bmpbuttn.cpp b/src/univ/bmpbuttn.cpp
index 2044a4bea8..ca8d01378a 100644
--- a/src/univ/bmpbuttn.cpp
+++ b/src/univ/bmpbuttn.cpp
@@ -94,6 +94,7 @@ bool wxBitmapButton::ChangeBitmap(const wxBitmap& bmp)
         return false;
 
     m_bitmap = bitmap;
+    SetInitialSize(bitmap.GetSize());
 
     return true;
 }