diff --git a/dockers/mobilizon/config.exs b/dockers/mobilizon/config.exs
index caece0b..dcbff08 100644
--- a/dockers/mobilizon/config.exs
+++ b/dockers/mobilizon/config.exs
@@ -44,7 +44,7 @@ config :mobilizon, Mobilizon.Storage.Repo,
 
 config :mobilizon, Mobilizon.Web.Email.Mailer,
   adapter: Swoosh.Adapters.SMTP,
-  relay: System.get_env("MOBILIZON_SMTP_SERVER", "localhost"),
+  relay: System.get_env("MOBILIZON_SMTP_SERVER", "smtp"),
   port: System.get_env("MOBILIZON_SMTP_PORT", "25"),
   username: System.get_env("MOBILIZON_SMTP_USERNAME", nil),
   password: System.get_env("MOBILIZON_SMTP_PASSWORD", nil),