diff --git a/types/unit/service.pp b/types/unit/service.pp
index 447a104f..2dce2b2b 100644
--- a/types/unit/service.pp
+++ b/types/unit/service.pp
@@ -103,6 +103,7 @@
     Optional['PrivateTmp']                => Boolean,
     Optional['RuntimeDirectory']          => String,
     Optional['RuntimeDirectoryMode']      => Stdlib::Filemode,
+    Optional['StateDirectory']            => String,
     Optional['LogsDirectory']             => String,
     Optional['LogsDirectoryMode']         => Stdlib::Filemode,
     Optional['ProtectSystem']             => Variant[Boolean, Enum['full', 'strict']],