diff --git a/cwltool/utils.py b/cwltool/utils.py
index 6326af4f6..ba34ffde0 100644
--- a/cwltool/utils.py
+++ b/cwltool/utils.py
@@ -245,9 +245,9 @@ def random_outdir() -> str:
 fcntl: Optional[ModuleType] = None
 msvcrt: Optional[ModuleType] = None
 try:
-    import fcntl  # type: ignore
+    import fcntl
 except ImportError:
-    import msvcrt  # type: ignore
+    import msvcrt
 
 
 def shared_file_lock(fd: IO[Any]) -> None:
diff --git a/mypy-requirements.txt b/mypy-requirements.txt
index 3000af08c..696317632 100644
--- a/mypy-requirements.txt
+++ b/mypy-requirements.txt
@@ -1,4 +1,4 @@
-mypy==0.991
+mypy==1.0.0  # also update pyproject.toml
 ruamel.yaml>=0.16.0,<0.17.22
 schema-salad>=8.2.20211104054942,<9
 cwl-utils >=0.19
diff --git a/pyproject.toml b/pyproject.toml
index fcffb3983..fd2087a27 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -2,7 +2,7 @@
 requires = [
     "setuptools>=45",
     'mypy==0.971; python_version == "3.6"',  # last version for Python 3.6
-    'mypy==0.991; python_version >= "3.7"',
+    'mypy==1.0; python_version >= "3.7"',  # also update mypy-requirements.txt
     "types-pkg_resources",
     "types-requests",
     "types-psutil",