diff --git a/stdlib/io.pyi b/stdlib/io.pyi
index ee4eda1b4eb0..950cd8d9eeb1 100644
--- a/stdlib/io.pyi
+++ b/stdlib/io.pyi
@@ -193,11 +193,13 @@ class StringIO(TextIOWrapper):
     name: Any
     def getvalue(self) -> str: ...
 
-class IncrementalNewlineDecoder(codecs.IncrementalDecoder):
+class IncrementalNewlineDecoder:
     def __init__(self, decoder: codecs.IncrementalDecoder | None, translate: bool, errors: str = ...) -> None: ...
     def decode(self, input: ReadableBuffer | str, final: bool = False) -> str: ...
     @property
     def newlines(self) -> str | tuple[str, ...] | None: ...
+    def reset(self) -> None: ...
+    def getstate(self) -> tuple[bytes, int]: ...
     def setstate(self, __state: tuple[bytes, int]) -> None: ...
 
 if sys.version_info >= (3, 10):