diff --git a/docker-compose.yml b/docker-compose.yml
index 9031794e..448e8d17 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -80,9 +80,9 @@ services:
       CORS: "https://sel2-1.ugent.be"
       DISABLE_AUTH: "false"
       ERROR_LOGGER: "false"
-      SMTP_HOST: ""
-      SMTP_PORT: ""
-      SMTP_MAIL_ADDRESS: ""
+      SMTP_HOST: $SMTP_HOST
+      SMTP_PORT: $SMTP_PORT
+      SMTP_MAIL_ADDRESS: $SMTP_MAIL_ADDRESS
       SMTP_MAIL_PASSWORD: $SMTP_MAIL_PASSWORD
       SENTRY_DSN: $SENTRY_DSN
     restart: always