diff --git a/types/gapi.auth2/index.d.ts b/types/gapi.auth2/index.d.ts
index 4cdef77a80..7dbdb222c3 100644
--- a/types/gapi.auth2/index.d.ts
+++ b/types/gapi.auth2/index.d.ts
@@ -27,7 +27,7 @@ declare namespace gapi.auth2 {
      * Signs in the user using the specified options.
      * If no option specified here, fallback to the options specified to gapi.auth2.init().
      */
-    signIn(options?: SigninOptions | SigninOptionsBuilder): any;
+    signIn(options?: SigninOptions | SigninOptionsBuilder): Promise<GoogleUser>;
 
     /**
      * Signs out all accounts from the application.