diff --git a/IPython/html/static/widgets/js/widget.js b/IPython/html/static/widgets/js/widget.js
index 315b205..b20e21d 100644
--- a/IPython/html/static/widgets/js/widget.js
+++ b/IPython/html/static/widgets/js/widget.js
@@ -646,7 +646,7 @@ define(["widgets/js/manager",
* returns a promise that resolves after this removal is done
*/
var that = this;
- Promise.all(this.views).then(function(views) {
+ return Promise.all(this.views).then(function(views) {
for (var i = 0; i < that.views.length; i++) {
that._remove_view.call(that._handler_context, views[i]);
}