diff --git a/stdlib/3/_winapi.pyi b/stdlib/3/_winapi.pyi
index 24767ea5073b..af6c9231b05c 100644
--- a/stdlib/3/_winapi.pyi
+++ b/stdlib/3/_winapi.pyi
@@ -1,4 +1,4 @@
-from typing import Any, Union, Tuple, Optional, Dict, NoReturn, Sequence
+from typing import Any, Union, Tuple, Optional, overload, Dict, NoReturn, Sequence
 
 CREATE_NEW_CONSOLE: int
 CREATE_NEW_PROCESS_GROUP: int
@@ -45,7 +45,13 @@ WAIT_OBJECT_0: int
 WAIT_TIMEOUT: int
 
 def CloseHandle(handle: int) -> None: ...
-def ConnectNamedPipe(handle: int, overlapped: Union[int, bool] = ...) -> None: ...
+
+# TODO: once literal types are supported, overload with Literal[True/False]
+@overload
+def ConnectNamedPipe(handle: int, overlapped: Union[int, bool]) -> Any: ...
+@overload
+def ConnectNamedPipe(handle: int) -> None: ...
+
 def CreateFile(file_name: str, desired_access: int, share_mode: int, security_attributes: int, creation_disposition: int, flags_and_attributes: int, template_file: int) -> int: ...
 def CreateJunction(src_path: str, dest_path: str) -> None: ...
 def CreateNamedPipe(name: str, open_mode: int, pipe_mode: int, max_instances: int, out_buffer_size: int, in_buffer_size: int, default_timeout: int, security_attributes: int) -> int: ...
@@ -63,13 +69,25 @@ def GetStdHandle(std_handle: int) -> int: ...
 def GetVersion() -> int: ...
 def OpenProcess(desired_access: int, inherit_handle: bool, process_id: int) -> int: ...
 def PeekNamedPipe(handle: int, size: int = ...) -> Union[Tuple[int, int], Tuple[bytes, int, int]]: ...
-def ReadFile(handle: int, size: int, overlapped: Union[int, bool] = ...) -> Tuple[bytes, int]: ...
+
+# TODO: once literal types are supported, overload with Literal[True/False]
+@overload
+def ReadFile(handle: int, size: int, overlapped: Union[int, bool]) -> Any: ...
+@overload
+def ReadFile(handle: int, size: int) -> Tuple[int, int]: ...
+
 def SetNamedPipeHandleState(named_pipe: int, mode: Optional[int], max_collection_count: Optional[int], collect_data_timeout: Optional[int]) -> None: ...
 def TerminateProcess(handle: int, exit_code: int) -> None: ...
 def WaitForMultipleObjects(handle_seq: Sequence[int], wait_flag: bool, milliseconds: int = ...) -> int: ...
 def WaitForSingleObject(handle: int, milliseconds: int) -> int: ...
 def WaitNamedPipe(name: str, timeout: int) -> None: ...
-def WriteFile(handle: int, buffer: bytes, overlapped: Union[int, bool] = ...): ...
+
+# TODO: once literal types are supported, overload with Literal[True/False]
+@overload
+def WriteFile(handle: int, buffer: bytes, overlapped: Union[int, bool]) -> Any: ...
+@overload
+def WriteFile(handle: int, buffer: bytes) -> Tuple[bytes, int]: ...
+
 
 class Overlapped:
     event: int = ...