diff --git a/gdk/gdktoplevelsize.c b/gdk/gdktoplevelsize.c
index e5802782d4..7cd09ebd5e 100644
--- a/gdk/gdktoplevelsize.c
+++ b/gdk/gdktoplevelsize.c
@@ -118,6 +118,20 @@ gdk_toplevel_size_set_min_size (GdkToplevelSize *size,
   size->min_height = min_height;
 }
 
+void
+gdk_toplevel_size_set_margin (GdkToplevelSize *size,
+                              int              left,
+                              int              right,
+                              int              top,
+                              int              bottom)
+{
+  size->margin.is_valid = TRUE;
+  size->margin.left = left;
+  size->margin.right = right;
+  size->margin.top = top;
+  size->margin.bottom = bottom;
+}
+
 void
 gdk_toplevel_size_validate (GdkToplevelSize *size)
 {
diff --git a/gdk/gdktoplevelsize.h b/gdk/gdktoplevelsize.h
index 013a061ee9..41f8a4a604 100644
--- a/gdk/gdktoplevelsize.h
+++ b/gdk/gdktoplevelsize.h
@@ -54,6 +54,13 @@ void                    gdk_toplevel_size_set_min_size  (GdkToplevelSize       *
                                                          int                    min_width,
                                                          int                    min_height);
 
+GDK_AVAILABLE_IN_ALL
+void                    gdk_toplevel_size_set_margin    (GdkToplevelSize       *size,
+                                                         int                    left,
+                                                         int                    right,
+                                                         int                    top,
+                                                         int                    bottom);
+
 G_END_DECLS
 
 #endif /* __GDK_TOPLEVEL_SIZE_H__ */
diff --git a/gdk/gdktoplevelsizeprivate.h b/gdk/gdktoplevelsizeprivate.h
index 3576513888..f2c4461bf9 100644
--- a/gdk/gdktoplevelsizeprivate.h
+++ b/gdk/gdktoplevelsizeprivate.h
@@ -30,6 +30,14 @@ struct _GdkToplevelSize
   int height;
   int min_width;
   int min_height;
+
+  struct {
+    gboolean is_valid;
+    int left;
+    int right;
+    int top;
+    int bottom;
+  } margin;
 };
 
 void gdk_toplevel_size_init (GdkToplevelSize *size,
diff --git a/gtk/gtkwindow.c b/gtk/gtkwindow.c
index fc2cd4a986..67c9d721ba 100644
--- a/gtk/gtkwindow.c
+++ b/gtk/gtkwindow.c
@@ -4364,6 +4364,13 @@ toplevel_compute_size (GdkToplevel     *toplevel,
   min_height = MIN (min_height + shadow.top + shadow.bottom, height);
 
   gdk_toplevel_size_set_min_size (size, min_width, min_height);
+
+  if (priv->use_client_shadow)
+    {
+      gdk_toplevel_size_set_margin (size,
+                                    shadow.left, shadow.right,
+                                    shadow.top, shadow.bottom);
+    }
 }
 
 static void