diff --git a/net/compose.yaml b/net/compose.yaml
index 9386a79..a78b2ee 100644
--- a/net/compose.yaml
+++ b/net/compose.yaml
@@ -234,12 +234,13 @@ services:
       MP_SMTP_AUTH_ACCEPT_ANY: 1
       MP_SMTP_AUTH_ALLOW_INSECURE: 1
       MP_MAX_MESSAGES: 5000
-      # SMTP relay to IONOS via environment variables
-      MP_SMTP_RELAY_HOST: ${EMAIL_SMTP_HOST}
-      MP_SMTP_RELAY_PORT: ${EMAIL_SMTP_PORT}
-      MP_SMTP_RELAY_USER: ${EMAIL_SMTP_USER}
-      MP_SMTP_RELAY_PASS: ${EMAIL_SMTP_PASSWORD}
-      MP_SMTP_RELAY_AUTH: plain
+      # SMTP forwarding to IONOS via environment variables
+      MP_SMTP_FORWARD_HOST: ${EMAIL_SMTP_HOST}
+      MP_SMTP_FORWARD_PORT: ${EMAIL_SMTP_PORT}
+      MP_SMTP_FORWARD_USERNAME: ${EMAIL_SMTP_USER}
+      MP_SMTP_FORWARD_PASSWORD: ${EMAIL_SMTP_PASSWORD}
+      MP_SMTP_FORWARD_AUTH: plain
+      MP_SMTP_FORWARD_TLS: "true"
     volumes:
       - mailpit_data:/data
     networks: