diff --git a/message/output/email/message_output_email.php b/message/output/email/message_output_email.php
index c48e238a51d..89b3f004a27 100644
--- a/message/output/email/message_output_email.php
+++ b/message/output/email/message_output_email.php
@@ -75,7 +75,7 @@ class message_output_email extends message_output {
         $string = get_string('email','message_email') . ': ' . html_writer::empty_tag('input', $inputattributes);
 
         if (empty($preferences->email_email) && !empty($preferences->userdefaultemail)) {
-            $string .= ' ('.get_string('default').': '.$preferences->userdefaultemail.')';
+            $string .= ' ('.get_string('default').': '.s($preferences->userdefaultemail).')';
         }
 
         if (!empty($preferences->email_email) && !validate_email($preferences->email_email)) {