diff --git a/defaults/main.yml b/defaults/main.yml
index ce192e6..67148bd 100644
--- a/defaults/main.yml
+++ b/defaults/main.yml
@@ -2,7 +2,7 @@
 thredds_install: True
 thredds_upgrade: False
 thredds_force_data_reset: False
-thredds_version: 4.6.16.1
+thredds_version: 4.6.21
 thredds_data_content_dir: /data/thredds_contents
 thredds_server_name: 'Thredds instance'
 thredds_logo_url: '/thredds/threddsIcon.gif'