diff --git a/nginx/mailcow.conf b/nginx/mailcow.conf
index 920aacc..1f6151d 100644
--- a/nginx/mailcow.conf
+++ b/nginx/mailcow.conf
@@ -66,7 +66,8 @@ server {
 
   include /etc/nginx/snippets/ssl.conf;
   ssl_trusted_certificate /opt/mailcow-dockerized/data/assets/ssl/cert.pem;
-  
+ 
+  add_header Strict-Transport-Security "max-age=16070400";
   add_header Content-Security-Policy "upgrade-insecure-requests";
     
   include /etc/nginx/snippets/letsencrypt.conf;