diff --git a/compose.yml b/compose.yml
index 9c70c22..79c2496 100644
--- a/compose.yml
+++ b/compose.yml
@@ -15,4 +15,5 @@ services:
       - SMTP_HOSTNAME
       - SMTP_USERNAME
       - SMTP_PASSWORD
+      - SMTP_PORT
       - MAIL_FROM_ADDRESS