diff --git a/clutter/clutter/clutter-box-layout.c b/clutter/clutter/clutter-box-layout.c
index a3197f43f..3f5b9db2a 100644
--- a/clutter/clutter/clutter-box-layout.c
+++ b/clutter/clutter/clutter-box-layout.c
@@ -623,6 +623,8 @@ get_preferred_size_for_opposite_orientation (ClutterBoxLayout   *self,
     }
   else
     {
+      size -= (nvis_children - 1) * priv->spacing;
+
       /* Bring children up to size first */
       if (isnormal (size) || size == 0)
         {