diff --git a/nixos/modules/services/security/vaultwarden/default.nix b/nixos/modules/services/security/vaultwarden/default.nix
index b43ecc58f156..5c1b9e1ed114 100644
--- a/nixos/modules/services/security/vaultwarden/default.nix
+++ b/nixos/modules/services/security/vaultwarden/default.nix
@@ -173,6 +173,7 @@ in
     domain = lib.mkOption {
       type = with lib.types; nullOr str;
       default = null;
+      example = "bitwarden.example.com";
       description = "The domain under which VaultWarden will be reachable.";
     };