diff --git a/externs/olx.js b/externs/olx.js
index 6fc1c709ef..e909141fb5 100644
--- a/externs/olx.js
+++ b/externs/olx.js
@@ -6155,6 +6155,9 @@ olx.source.TileJSONOptions.prototype.wrapX;
  *     gutter: (number|undefined),
  *     hidpi: (boolean|undefined),
  *     logo: (string|olx.LogoOptions|undefined),
+ *     tileClass: (function(new: ol.ImageTile, ol.TileCoord,
+ *                          ol.TileState, string, ?string,
+ *                          ol.TileLoadFunctionType)|undefined),
  *     tileGrid: (ol.tilegrid.TileGrid|undefined),
  *     projection: ol.ProjectionLike,
  *     reprojectionErrorThreshold: (number|undefined),
@@ -6237,6 +6240,16 @@ olx.source.TileWMSOptions.prototype.hidpi;
 olx.source.TileWMSOptions.prototype.logo;
 
 
+/**
+ * Class used to instantiate image tiles. Default is {@link ol.ImageTile}.
+ * @type {function(new: ol.ImageTile, ol.TileCoord,
+ *                 ol.TileState, string, ?string,
+ *                 ol.TileLoadFunctionType)|undefined}
+ * @api
+ */
+olx.source.TileWMSOptions.prototype.tileClass;
+
+
 /**
  * Tile grid. Base this on the resolutions, tilesize and extent supported by the
  * server.
diff --git a/src/ol/source/tilewms.js b/src/ol/source/tilewms.js
index 8d70b67e95..29fc1aa751 100644
--- a/src/ol/source/tilewms.js
+++ b/src/ol/source/tilewms.js
@@ -42,6 +42,7 @@ ol.source.TileWMS = function(opt_options) {
     opaque: !transparent,
     projection: options.projection,
     reprojectionErrorThreshold: options.reprojectionErrorThreshold,
+    tileClass: options.tileClass,
     tileGrid: options.tileGrid,
     tileLoadFunction: options.tileLoadFunction,
     url: options.url,