diff --git a/src/STS/Controllers/ShibbolethController.cs b/src/STS/Controllers/ShibbolethController.cs
index 4a385448e21cb5c85a67a658bf96025073cacd13..6ffd1f8e0e503603a8752495b245c7eb44a4cd2f 100644
--- a/src/STS/Controllers/ShibbolethController.cs
+++ b/src/STS/Controllers/ShibbolethController.cs
@@ -147,7 +147,7 @@ namespace Coscine.Api.STS.Controllers
         /// <param name="entityId">Specific Identitiy Provider to be redirect to</param>
         /// <returns>ChallengeResult</returns>
         [Route("[controller]/login")]
-        public ActionResult Login(string returnUrl, string entityId = null)
+        public ActionResult Login(string returnUrl = "/", string entityId = null)
         {
             var provider = "Saml2";
             var redirectUrl = Program.MainUrl + "/Shibboleth/callback?returnUrl=" + returnUrl;