diff --git a/stdlib/encodings/utf_8.pyi b/stdlib/encodings/utf_8.pyi
index 568fa6013..8e7375619 100644
--- a/stdlib/encodings/utf_8.pyi
+++ b/stdlib/encodings/utf_8.pyi
@@ -1,11 +1,12 @@
 import codecs
+from _typeshed import ReadableBuffer
 
 class IncrementalEncoder(codecs.IncrementalEncoder):
     def encode(self, input: str, final: bool = ...) -> bytes: ...
 
 class IncrementalDecoder(codecs.BufferedIncrementalDecoder):
     @staticmethod
-    def _buffer_decode(__data: bytes, __errors: str | None = ..., __final: bool = ...) -> tuple[str, int]: ...
+    def _buffer_decode(__data: ReadableBuffer, __errors: str | None = ..., __final: bool = ...) -> tuple[str, int]: ...
 
 class StreamWriter(codecs.StreamWriter):
     @staticmethod
@@ -13,8 +14,8 @@ class StreamWriter(codecs.StreamWriter):
 
 class StreamReader(codecs.StreamReader):
     @staticmethod
-    def decode(__data: bytes, __errors: str | None = ..., __final: bool = ...) -> tuple[str, int]: ...
+    def decode(__data: ReadableBuffer, __errors: str | None = ..., __final: bool = ...) -> tuple[str, int]: ...
 
 def getregentry() -> codecs.CodecInfo: ...
 def encode(__str: str, __errors: str | None = ...) -> tuple[bytes, int]: ...
-def decode(input: bytes, errors: str | None = ...) -> tuple[str, int]: ...
+def decode(input: ReadableBuffer, errors: str | None = ...) -> tuple[str, int]: ...
diff --git a/stdlib/encodings/utf_8_sig.pyi b/stdlib/encodings/utf_8_sig.pyi
index ad0d5bdc4..27171063f 100644
--- a/stdlib/encodings/utf_8_sig.pyi
+++ b/stdlib/encodings/utf_8_sig.pyi
@@ -1,4 +1,5 @@
 import codecs
+from _typeshed import ReadableBuffer
 
 class IncrementalEncoder(codecs.IncrementalEncoder):
     def __init__(self, errors: str = ...) -> None: ...
@@ -8,14 +9,14 @@ class IncrementalEncoder(codecs.IncrementalEncoder):
 
 class IncrementalDecoder(codecs.BufferedIncrementalDecoder):
     def __init__(self, errors: str = ...) -> None: ...
-    def _buffer_decode(self, input: bytes, errors: str | None, final: bool) -> tuple[str, int]: ...
+    def _buffer_decode(self, input: ReadableBuffer, errors: str | None, final: bool) -> tuple[str, int]: ...
 
 class StreamWriter(codecs.StreamWriter):
     def encode(self, input: str, errors: str | None = ...) -> tuple[bytes, int]: ...
 
 class StreamReader(codecs.StreamReader):
-    def decode(self, input: bytes, errors: str | None = ...) -> tuple[str, int]: ...
+    def decode(self, input: ReadableBuffer, errors: str | None = ...) -> tuple[str, int]: ...
 
 def getregentry() -> codecs.CodecInfo: ...
 def encode(input: str, errors: str | None = ...) -> tuple[bytes, int]: ...
-def decode(input: bytes, errors: str | None = ...) -> tuple[str, int]: ...
+def decode(input: ReadableBuffer, errors: str | None = ...) -> tuple[str, int]: ...