diff --git a/services/src/main/java/org/keycloak/services/resources/WelcomeResource.java b/services/src/main/java/org/keycloak/services/resources/WelcomeResource.java
index 8d69420525..6093879645 100755
--- a/services/src/main/java/org/keycloak/services/resources/WelcomeResource.java
+++ b/services/src/main/java/org/keycloak/services/resources/WelcomeResource.java
@@ -119,6 +119,10 @@ public class WelcomeResource {
             String password = formData.getFirst("password");
             String passwordConfirmation = formData.getFirst("passwordConfirmation");
 
+            if (username != null) {
+                username = username.trim();
+            }
+
             if (username == null || username.length() == 0) {
                 return createWelcomePage(null, "Username is missing");
             }