diff --git a/setup/flavors/compose/mailu.env b/setup/flavors/compose/mailu.env
index 7d160011..5ccd8ace 100644
--- a/setup/flavors/compose/mailu.env
+++ b/setup/flavors/compose/mailu.env
@@ -174,7 +174,7 @@ DB_PW={{ secret(16) }}
 {% if postgresql == 'external' or db_flavor == 'mysql' %}
 DB_USER={{ db_user }}
 DB_PW={{ db_pw }}
-DB_URL={{ db_url }}
+DB_HOST={{ db_url }}
 DB_NAME={{ db_name }}
 {% endif %}