diff --git a/gtk2_ardour/port_matrix.cc b/gtk2_ardour/port_matrix.cc
index 9336d520e8..8d4a8e5696 100644
--- a/gtk2_ardour/port_matrix.cc
+++ b/gtk2_ardour/port_matrix.cc
@@ -765,7 +765,15 @@ PortMatrix::setup_notebooks ()
 		Label* label = manage (new Label ((*i)->name));
 		label->set_angle (_arrangement == LEFT_TO_BOTTOM ? 90 : -90);
 		label->show ();
-		_vnotebook.prepend_page (*dummy, *label);
+		if (_arrangement == LEFT_TO_BOTTOM) {
+			_vnotebook.prepend_page (*dummy, *label);
+		} else {
+			/* Reverse the order of vertical tabs when they are on the right hand side
+			   so that from top to bottom it is the same order as that from left to right
+			   for the top tabs.
+			*/
+			_vnotebook.append_page (*dummy, *label);
+		}
 	}
 
 	for (PortGroupList::List::const_iterator i = _ports[_column_index].begin(); i != _ports[_column_index].end(); ++i) {