diff --git a/roles/mta_sts/templates/nginx.d.conf.j2 b/roles/mta_sts/templates/nginx.d.conf.j2
index 31e9b74e478413b72d5fd608e24215253d1613c3..f17ebec4e4408f3aed68a13710c8302cc0d71276 100644
--- a/roles/mta_sts/templates/nginx.d.conf.j2
+++ b/roles/mta_sts/templates/nginx.d.conf.j2
@@ -32,7 +32,7 @@ server {
 
     location = /.well-known/mta-sts.txt {
         default_type text/plain;
-        return 200 'version: STSv1\nmode: testing\nmax_age: 604800\nmx: {{ config.mx | join('\\nmx: ')}}\n';
+        return 200 'version: STSv1\nmode: enforce\nmax_age: 2592000\nmx: {{ config.mx | join('\\nmx: ')}}\n';
     }
 
     location / {