diff --git a/src/msw/headerctrl.cpp b/src/msw/headerctrl.cpp
index 1694a8e288..966f6b04e5 100644
--- a/src/msw/headerctrl.cpp
+++ b/src/msw/headerctrl.cpp
@@ -195,7 +195,7 @@ wxSize wxHeaderCtrl::DoGetBestSize() const
         return wxControl::DoGetBestSize();
     }
 
-    return wxSize(wpos.cx, wpos.cy);
+    return wxSize(wxDefaultCoord, wpos.cy);
 }
 
 // ----------------------------------------------------------------------------