diff --git a/wxPython/contrib/gizmos/wxCode/src/treelistctrl.cpp b/wxPython/contrib/gizmos/wxCode/src/treelistctrl.cpp
index 2f719e27d2..db6e5bd72f 100644
--- a/wxPython/contrib/gizmos/wxCode/src/treelistctrl.cpp
+++ b/wxPython/contrib/gizmos/wxCode/src/treelistctrl.cpp
@@ -1336,7 +1336,7 @@ int wxTreeListHeaderWindow::XToCol(int x)
 
 void wxTreeListHeaderWindow::RefreshColLabel(int col)
 {
-    if ( col > GetColumnCount() )
+    if ( col >= GetColumnCount() )
         return;
     
     int x = 0;