diff --git a/stdlib/2/__builtin__.pyi b/stdlib/2/__builtin__.pyi
index 06e08793d..aa4953e88 100644
--- a/stdlib/2/__builtin__.pyi
+++ b/stdlib/2/__builtin__.pyi
@@ -7,7 +7,7 @@ from typing import (
     TypeVar, Iterator, Iterable, NoReturn, overload,
     Sequence, Mapping, Tuple, List, Any, Dict, Callable, Generic, Set,
     AbstractSet, FrozenSet, Sized, Reversible, SupportsInt, SupportsFloat, SupportsAbs,
-    SupportsRound, IO, BinaryIO, Union, AnyStr, MutableSequence, MutableMapping,
+    SupportsComplex, SupportsRound, IO, BinaryIO, Union, AnyStr, MutableSequence, MutableMapping,
     MutableSet, ItemsView, KeysView, ValuesView, Optional, Container, Type
 )
 from abc import abstractmethod, ABCMeta
@@ -187,6 +187,8 @@ class complex:
     def __init__(self, re: float = ..., im: float = ...) -> None: ...
     @overload
     def __init__(self, s: str) -> None: ...
+    @overload
+    def __init__(self, s: SupportsComplex) -> None: ...
 
     @property
     def real(self) -> float: ...
@@ -213,6 +215,7 @@ class complex:
     def __neg__(self) -> complex: ...
     def __pos__(self) -> complex: ...
 
+    def __complex__(self) -> complex: ...
     def __str__(self) -> str: ...
     def __abs__(self) -> float: ...
     def __hash__(self) -> int: ...
diff --git a/stdlib/3/builtins.pyi b/stdlib/3/builtins.pyi
index 8db945191..f919fbc2e 100644
--- a/stdlib/3/builtins.pyi
+++ b/stdlib/3/builtins.pyi
@@ -4,8 +4,8 @@ from typing import (
     TypeVar, Iterator, Iterable, overload, Container,
     Sequence, MutableSequence, Mapping, MutableMapping, NoReturn, Tuple, List, Any, Dict, Callable, Generic,
     Set, AbstractSet, FrozenSet, MutableSet, Sized, Reversible, SupportsInt, SupportsFloat,
-    SupportsBytes, SupportsAbs, SupportsRound, IO, Union, ItemsView, KeysView, ValuesView,
-    ByteString, Optional, AnyStr, Type,
+    SupportsComplex, SupportsBytes, SupportsAbs, SupportsRound, IO, Union, ItemsView, KeysView,
+    ValuesView, ByteString, Optional, AnyStr, Type,
 )
 from abc import abstractmethod, ABCMeta
 from types import TracebackType, CodeType
@@ -204,6 +204,8 @@ class complex:
     def __init__(self, re: float = ..., im: float = ...) -> None: ...
     @overload
     def __init__(self, s: str) -> None: ...
+    @overload
+    def __init__(self, s: SupportsComplex) -> None: ...
 
     @property
     def real(self) -> float: ...
@@ -229,6 +231,7 @@ class complex:
     def __pos__(self) -> complex: ...
 
     def __str__(self) -> str: ...
+    def __complex__(self) -> complex: ...
     def __abs__(self) -> float: ...
     def __hash__(self) -> int: ...
     def __bool__(self) -> bool: ...