diff --git a/stdlib/@tests/stubtest_allowlists/py315.txt b/stdlib/@tests/stubtest_allowlists/py315.txt
index 7354dac4dc90..38ae4bfef87e 100644
--- a/stdlib/@tests/stubtest_allowlists/py315.txt
+++ b/stdlib/@tests/stubtest_allowlists/py315.txt
@@ -28,8 +28,6 @@ importlib.abc.InspectLoader.source_to_code
 importlib.abc.MetaPathFinder.discover
 importlib.abc.PathEntryFinder.discover
 importlib.resources._common.package_to_anchor
-mailbox.Mailbox.__enter__
-mailbox.Mailbox.__exit__
 mailbox._ProxyFile.__class_getitem__
 multiprocessing.process.BaseProcess.__init__
 threading.Condition.locked
diff --git a/stdlib/mailbox.pyi b/stdlib/mailbox.pyi
index 961c0f5e81f7..4215120a5753 100644
--- a/stdlib/mailbox.pyi
+++ b/stdlib/mailbox.pyi
@@ -129,6 +129,11 @@ class Mailbox(Generic[_MessageT_co]):
     def unlock(self) -> None: ...
     @abstractmethod
     def close(self) -> None: ...
+    if sys.version_info >= (3, 15):
+        def __enter__(self) -> Self: ...
+        def __exit__(
+            self, type: type[BaseException] | None, value: BaseException | None, traceback: TracebackType | None
+        ) -> None: ...
     # Undocumented, called by subclasses to parse added messages.
     def _dump_message(self, message: _MessageData, target: SupportsWrite[bytes], mangle_from_: bool = False) -> None: ...
     def __class_getitem__(cls, item: Any, /) -> GenericAlias: ...