diff --git a/app/assets/javascripts/discourse/controllers/create-account.js.es6 b/app/assets/javascripts/discourse/controllers/create-account.js.es6
index 91beec59f62..694c89d323e 100644
--- a/app/assets/javascripts/discourse/controllers/create-account.js.es6
+++ b/app/assets/javascripts/discourse/controllers/create-account.js.es6
@@ -197,7 +197,7 @@ export default Discourse.Controller.extend(Discourse.ModalFunctionality, {
     }
 
     // If too long
-    if (this.get('accountUsername').length > 15) {
+    if (this.get('accountUsername').length > 20) {
       return Discourse.InputValidation.create({
         failed: true,
         reason: I18n.t('user.username.too_long')
diff --git a/app/assets/javascripts/discourse/templates/modal/create_account.js.handlebars b/app/assets/javascripts/discourse/templates/modal/create_account.js.handlebars
index 4dfa9d191ae..54137827050 100644
--- a/app/assets/javascripts/discourse/templates/modal/create_account.js.handlebars
+++ b/app/assets/javascripts/discourse/templates/modal/create_account.js.handlebars
@@ -30,7 +30,7 @@
       <tr class="input">
             <td class="label"><label for='new-account-username'>{{i18n user.username.title}}</label></td>
             <td>
-            {{input value=accountUsername id="new-account-username" maxlength="15"}}
+            {{input value=accountUsername id="new-account-username" maxlength="20"}}
             &nbsp;{{input-tip validation=usernameValidation}}
             </td>
       </tr>
diff --git a/test/javascripts/controllers/create_account_controller_test.js b/test/javascripts/controllers/create_account_controller_test.js
index 45ca92ee8e2..8bdd59f70ff 100644
--- a/test/javascripts/controllers/create_account_controller_test.js
+++ b/test/javascripts/controllers/create_account_controller_test.js
@@ -10,7 +10,7 @@ test('basicUsernameValidation', function() {
 
   testInvalidUsername('', undefined);
   testInvalidUsername('x', I18n.t('user.username.too_short'));
-  testInvalidUsername('1234567890123456', I18n.t('user.username.too_long'));
+  testInvalidUsername('123456789012345678901', I18n.t('user.username.too_long'));
 
   var controller = controllerFor('create-account');
   controller.set('accountUsername',   'porkchops');