diff --git a/backbone/backbone.d.ts b/backbone/backbone.d.ts
index 32205e1f9..cbee545e9 100644
--- a/backbone/backbone.d.ts
+++ b/backbone/backbone.d.ts
@@ -80,6 +80,7 @@ declare module Backbone {
     }
 
     class ModelBase extends Events {
+        url: string;
         url(): any;
         parse(response: any, options?: any): any;
         toJSON(options?: any): any;