diff --git a/lib/client.js b/lib/client.js
index 7bbb99f9b..a20c9de9c 100644
--- a/lib/client.js
+++ b/lib/client.js
@@ -197,7 +197,7 @@ MatrixClient.prototype.getIdentityServerUrl = function() {
  */
 MatrixClient.prototype.getDomain = function() {
     if (this.credentials && this.credentials.userId) {
-        return this.credentials.userId.split(':')[0];
+        return this.credentials.userId.replace(/^.*?:/, '');
     }
     return null;
 };