diff --git a/modules/services/databases/postgresql.nix b/modules/services/databases/postgresql.nix
index 92e6083d9485..9f1ca6e2ed12 100644
--- a/modules/services/databases/postgresql.nix
+++ b/modules/services/databases/postgresql.nix
@@ -118,6 +118,8 @@ in
 
         startOn = "started ${startDependency}";
 
+        environment = { TZ = config.time.timeZone; };
+
         preStart =
           ''
             if ! test -e ${cfg.dataDir}; then