diff --git a/types/autobahn/index.d.ts b/types/autobahn/index.d.ts
index 59bb2c404d..c62f6115af 100644
--- a/types/autobahn/index.d.ts
+++ b/types/autobahn/index.d.ts
@@ -190,6 +190,8 @@ declare namespace autobahn {
     export class Connection {
         constructor(options?: IConnectionOptions);
 
+        isOpen: boolean;
+        
         open(): void;
 
         close(reason?: string, message?: string): void;