diff --git a/mypy/funcplugins.py b/mypy/funcplugins.py
index 7d5c25248e0a..b1113ab30ae9 100644
--- a/mypy/funcplugins.py
+++ b/mypy/funcplugins.py
@@ -44,7 +44,7 @@ def open_callback(
         named_generic_type: Callable[[str, List[Type]], Type]) -> Type:
     """Infer a better return type for 'open'.
 
-    Infer IO[str] or IO[bytes] as the return value if the mode argument is not
+    Infer TextIO or BinaryIO as the return value if the mode argument is not
     given or is a literal.
     """
     mode = None
@@ -55,10 +55,9 @@ def open_callback(
     if mode is not None:
         assert isinstance(inferred_return_type, Instance)
         if 'b' in mode:
-            arg = named_generic_type('builtins.bytes', [])
+            return named_generic_type('typing.BinaryIO', [])
         else:
-            arg = named_generic_type('builtins.str', [])
-        return Instance(inferred_return_type.type, [arg])
+            return named_generic_type('typing.TextIO', [])
     return inferred_return_type
 
 
diff --git a/test-data/unit/pythoneval.test b/test-data/unit/pythoneval.test
index be05dafe20c8..c9ee1f322a28 100644
--- a/test-data/unit/pythoneval.test
+++ b/test-data/unit/pythoneval.test
@@ -400,7 +400,7 @@ f.write(b'x')
 f.foobar()
 [out]
 _program.py:3: error: Argument 1 to "write" of "IO" has incompatible type "bytes"; expected "str"
-_program.py:4: error: IO[str] has no attribute "foobar"
+_program.py:4: error: "TextIO" has no attribute "foobar"
 
 [case testOpenReturnTypeInference]
 reveal_type(open('x'))
@@ -409,9 +409,9 @@ reveal_type(open('x', 'rb'))
 mode = 'rb'
 reveal_type(open('x', mode))
 [out]
-_program.py:1: error: Revealed type is 'typing.IO[builtins.str]'
-_program.py:2: error: Revealed type is 'typing.IO[builtins.str]'
-_program.py:3: error: Revealed type is 'typing.IO[builtins.bytes]'
+_program.py:1: error: Revealed type is 'typing.TextIO'
+_program.py:2: error: Revealed type is 'typing.TextIO'
+_program.py:3: error: Revealed type is 'typing.BinaryIO'
 _program.py:5: error: Revealed type is 'typing.IO[Any]'
 
 [case testOpenReturnTypeInferenceSpecialCases]
@@ -421,10 +421,10 @@ reveal_type(open(file='x', mode='rb'))
 mode = 'rb'
 reveal_type(open(mode=mode, file='r'))
 [out]
-_testOpenReturnTypeInferenceSpecialCases.py:1: error: Revealed type is 'typing.IO[builtins.str]'
+_testOpenReturnTypeInferenceSpecialCases.py:1: error: Revealed type is 'typing.TextIO'
 _testOpenReturnTypeInferenceSpecialCases.py:1: error: Too few arguments for "open"
-_testOpenReturnTypeInferenceSpecialCases.py:2: error: Revealed type is 'typing.IO[builtins.bytes]'
-_testOpenReturnTypeInferenceSpecialCases.py:3: error: Revealed type is 'typing.IO[builtins.bytes]'
+_testOpenReturnTypeInferenceSpecialCases.py:2: error: Revealed type is 'typing.BinaryIO'
+_testOpenReturnTypeInferenceSpecialCases.py:3: error: Revealed type is 'typing.BinaryIO'
 _testOpenReturnTypeInferenceSpecialCases.py:5: error: Revealed type is 'typing.IO[Any]'
 
 [case testGenericPatterns]