diff --git a/stdlib/2.7/__builtin__.pyi b/stdlib/2.7/__builtin__.pyi
index 546202b29..2c877c285 100644
--- a/stdlib/2.7/__builtin__.pyi
+++ b/stdlib/2.7/__builtin__.pyi
@@ -714,7 +714,10 @@ def quit(code: int = ...) -> None: ...
 def range(x: int, y: int = 0, step: int = 1) -> List[int]: ...
 def raw_input(prompt: unicode = ...) -> str: ...
 
-def reduce(function: Callable[[_T, _T], _T], iterable: Iterable[_T], initializer: _T = None) -> _T: ...
+@overload
+def reduce(function: Callable[[_T, _S], _T], iterable: Iterable[_S], initializer: _T) -> _T: ...
+@overload
+def reduce(function: Callable[[_T, _T], _T], iterable: Iterable[_T]) -> _T: ...
 
 def reload(module: Any) -> Any: ...
 @overload