diff --git a/js/settings.js b/js/settings.js
index 1dc2ac0..07a2690 100644
--- a/js/settings.js
+++ b/js/settings.js
@@ -20,4 +20,11 @@ $(document).ready(function() {
       event.preventDefault();
     }
   });
+  $('#email_is_login').change(function(event) {
+    if (event.target.checked) {
+      $('.login-name-policy').addClass('hidden');
+    } else {
+      $('.login-name-policy').removeClass('hidden');
+    }
+  });
 });
diff --git a/templates/admin.php b/templates/admin.php
index 0679cc1..e68186f 100644
--- a/templates/admin.php
+++ b/templates/admin.php
@@ -59,13 +59,15 @@ foreach ($_['groups'] as $group) {
 		<label for="email_is_login"><?php p($l->t('Force email as login name')); ?></label>
 	</p>
 
-	<h3><?php p($l->t('Username policy')); ?></h3>
+	<div class="login-name-policy <?php if ($_['email_is_login'] === 'yes') { p('hidden'); } ?>">
+	<h3><?php p($l->t('Login name policy')); ?></h3>
 	<p>
 		<label>
 			<input type="text" id="username_policy_regex" name="username_policy_regex" value="<?php p($_['username_policy_regex']);?>" placeholder="E.g.: /^[a-z-]+\.[a-z-]+$/">
 		</label>
 	</p>
-	<em><?php p($l->t('If configured, usernames will be validated through the regular expression. If the validation fails the user is prompted with a generic error. Make sure your regex is working correctly.'));?></em>
+	<em><?php p($l->t('If configured, login names will be validated through the regular expression. If the validation fails the user is prompted with a generic error. Make sure your regex is working correctly.'));?></em>
+	</div>
 
 	<h3><?php p($l->t('User instructions')); ?></h3>
 	<em><?php p($l->t('Caution: The user instructions will not be translated and will therefore be displayed as configured below for all users regardless of their actual language.'));?></em>