diff --git a/stdlib/2/__builtin__.pyi b/stdlib/2/__builtin__.pyi
index 403bed0cbc91..da882b108605 100644
--- a/stdlib/2/__builtin__.pyi
+++ b/stdlib/2/__builtin__.pyi
@@ -69,6 +69,9 @@ if sys.version_info >= (3, 9):
 class _SupportsIndex(Protocol):
     def __index__(self) -> int: ...
 
+class _SupportsTrunc(Protocol):
+    def __trunc__(self) -> int: ...
+
 class _SupportsLessThan(Protocol):
     def __lt__(self, __other: Any) -> bool: ...
 
@@ -182,7 +185,7 @@ class super(object):
 
 class int:
     @overload
-    def __new__(cls: Type[_T], x: Union[Text, bytes, SupportsInt, _SupportsIndex] = ...) -> _T: ...
+    def __new__(cls: Type[_T], x: Union[Text, bytes, SupportsInt, _SupportsIndex, _SupportsTrunc] = ...) -> _T: ...
     @overload
     def __new__(cls: Type[_T], x: Union[Text, bytes, bytearray], base: int) -> _T: ...
     if sys.version_info >= (3, 8):
diff --git a/stdlib/2and3/builtins.pyi b/stdlib/2and3/builtins.pyi
index 403bed0cbc91..da882b108605 100644
--- a/stdlib/2and3/builtins.pyi
+++ b/stdlib/2and3/builtins.pyi
@@ -69,6 +69,9 @@ if sys.version_info >= (3, 9):
 class _SupportsIndex(Protocol):
     def __index__(self) -> int: ...
 
+class _SupportsTrunc(Protocol):
+    def __trunc__(self) -> int: ...
+
 class _SupportsLessThan(Protocol):
     def __lt__(self, __other: Any) -> bool: ...
 
@@ -182,7 +185,7 @@ class super(object):
 
 class int:
     @overload
-    def __new__(cls: Type[_T], x: Union[Text, bytes, SupportsInt, _SupportsIndex] = ...) -> _T: ...
+    def __new__(cls: Type[_T], x: Union[Text, bytes, SupportsInt, _SupportsIndex, _SupportsTrunc] = ...) -> _T: ...
     @overload
     def __new__(cls: Type[_T], x: Union[Text, bytes, bytearray], base: int) -> _T: ...
     if sys.version_info >= (3, 8):