diff --git a/src/Phpforce/SoapClient/Result/LoginResult.php b/src/Phpforce/SoapClient/Result/LoginResult.php
index e987329..e521c88 100644
--- a/src/Phpforce/SoapClient/Result/LoginResult.php
+++ b/src/Phpforce/SoapClient/Result/LoginResult.php
@@ -83,7 +83,7 @@ public function getServerInstance()
         }
 
         $match = preg_match(
-            '/https:\/\/(?<instance>[^-]+)\.salesforce\.com/',
+            '/https:\/\/(?<instance>.+)\.my\.salesforce\.com/',
             $this->serverUrl,
             $matches
         );