diff --git a/core/modules/filter/filter.module b/core/modules/filter/filter.module
index b55066f..6f172e7 100644
--- a/core/modules/filter/filter.module
+++ b/core/modules/filter/filter.module
@@ -1306,7 +1306,7 @@ function filter_filter_info() {
     'process callback' => '_filter_html',
     'settings callback' => '_filter_html_settings',
     'default settings' => array(
-      'allowed_html' => '<a> <em> <strong> <cite> <blockquote> <code> <ul> <ol> <li> <dl> <dt> <dd>',
+      'allowed_html' => '<a> <h2> <h3> <h4> <h5> <h6> <em> <strong> <cite> <blockquote> <code> <ul> <ol> <li> <dl> <dt> <dd>',
       'filter_html_help' => 1,
       'filter_html_nofollow' => 0,
     ),