diff --git a/src/ol/source/tilewmssource.js b/src/ol/source/tilewmssource.js
index 7faa7244b7..6f582b039c 100644
--- a/src/ol/source/tilewmssource.js
+++ b/src/ol/source/tilewmssource.js
@@ -84,7 +84,8 @@ ol.source.TileWMS = function(options) {
       tileExtent = tileGrid.getTileCoordExtent(
           new ol.TileCoord(tileCoord.z, x, tileCoord.y));
     }
-    if (!goog.isNull(extent) && !ol.extent.intersects(tileExtent, extent)) {
+    if (!goog.isNull(extent) && (!ol.extent.intersects(tileExtent, extent) ||
+        ol.extent.touches(tileExtent, extent))) {
       return null;
     }
     return new ol.TileCoord(tileCoord.z, x, tileCoord.y);