diff --git a/django-stubs/contrib/sessions/backends/base.pyi b/django-stubs/contrib/sessions/backends/base.pyi
index 90dabee0f..156c17cd2 100644
--- a/django-stubs/contrib/sessions/backends/base.pyi
+++ b/django-stubs/contrib/sessions/backends/base.pyi
@@ -1,4 +1,4 @@
-from datetime import datetime
+from datetime import datetime, timedelta
 from typing import Any
 
 VALID_KEY_CHARS: Any
@@ -37,7 +37,7 @@ class SessionBase(dict[str, Any]):
     def get_session_cookie_age(self) -> int: ...
     def get_expiry_age(self, **kwargs: Any) -> int: ...
     def get_expiry_date(self, **kwargs: Any) -> datetime: ...
-    def set_expiry(self, value: datetime | int | None) -> None: ...
+    def set_expiry(self, value: datetime | timedelta | int | None) -> None: ...
     def get_expire_at_browser_close(self) -> bool: ...
     def flush(self) -> None: ...
     def cycle_key(self) -> None: ...