diff --git a/ghost/admin/app/controllers/settings/apps/slack.js b/ghost/admin/app/controllers/settings/apps/slack.js
index ff69d6352e..e544745d14 100644
--- a/ghost/admin/app/controllers/settings/apps/slack.js
+++ b/ghost/admin/app/controllers/settings/apps/slack.js
@@ -65,6 +65,7 @@ export default Controller.extend({
         },
 
         updateURL(value) {
+            value = typeof value === 'string' ? value.trim() : value;
             this.set('model.url', value);
             this.get('model.errors').clear();
         },