diff --git a/interface/lib/plugins/mail_user_filter_plugin.inc.php b/interface/lib/plugins/mail_user_filter_plugin.inc.php
index 40defa8ea4e216c4db6204df105ea19a3fcceae2..5afd1c004494fc96062d253d3aa8f8779e6a235b 100644
--- a/interface/lib/plugins/mail_user_filter_plugin.inc.php
+++ b/interface/lib/plugins/mail_user_filter_plugin.inc.php
@@ -177,7 +177,7 @@ class mail_user_filter_plugin {
 				} elseif ($page_form->dataRecord["op"] == 'is') {
 					$content .= "^".$searchterm."$";
 				} elseif ($page_form->dataRecord["op"] == 'begins') {
-					$content .= " ".$searchterm."";
+					$content .= "^".$searchterm."";
 				} elseif ($page_form->dataRecord["op"] == 'ends') {
 					$content .= ".*".$searchterm."$";
 				}