diff --git a/constants.nix b/constants.nix
index e8de9ad..805fbf9 100644
--- a/constants.nix
+++ b/constants.nix
@@ -25,6 +25,10 @@ rec {
       subdomain = "f";
       fqdn = subdomain + "." + domain;
     };
+    mailserver = rec {
+      subdomain = "mail";
+      fqdn = subdomain + "." + domain;
+    };
     miniflux = {
       fqdn = "rss." + domain;
       port = 8085;
diff --git a/hosts/rx4/services/vaultwarden.nix b/hosts/rx4/services/vaultwarden.nix
index cffaeae..d9f8092 100644
--- a/hosts/rx4/services/vaultwarden.nix
+++ b/hosts/rx4/services/vaultwarden.nix
@@ -27,9 +27,9 @@ in
 
       SMTP_FROM = "vaultwarden@${domain}";
       SMTP_FROM_NAME = "${domain} Vaultwarden server";
-      SMTP_HOST = constants.hosts.sid.ip;
-      SMTP_PORT = 587;
-      SMTP_SECURITY = "starttls";
+      SMTP_HOST = constants.services.mailserver.fqdn;
+      SMTP_PORT = 465;
+      SMTP_SECURITY = "force_tls";
       SMTP_USERNAME = "vaultwarden@${domain}";
 
       ROCKET_ADDRESS = "127.0.0.1";
diff --git a/hosts/sid/services/mailserver.nix b/hosts/sid/services/mailserver.nix
index 024665c..c70433e 100644
--- a/hosts/sid/services/mailserver.nix
+++ b/hosts/sid/services/mailserver.nix
@@ -1,10 +1,14 @@
-{ inputs, ... }:
+{ inputs, constants, ... }:
 
+let
+  inherit (constants.services.mailserver) subdomain;
+in
 {
   imports = [ inputs.synix.nixosModules.mailserver ];
 
   mailserver = {
     enable = true;
+    inherit subdomain;
     stateVersion = 3;
     accounts = {
       sid = {