diff --git a/openstackclient/tests/functional/volume/v1/test_service.py b/openstackclient/tests/functional/volume/v1/test_service.py
index c921c46aaa..fee73f189c 100644
--- a/openstackclient/tests/functional/volume/v1/test_service.py
+++ b/openstackclient/tests/functional/volume/v1/test_service.py
@@ -64,10 +64,7 @@ class VolumeServiceTests(common.BaseVolumeTests):
             'enabled',
             cmd_output[0]['Status']
         )
-        self.assertEqual(
-            None,
-            cmd_output[0]['Disabled Reason']
-        )
+        self.assertIsNone(cmd_output[0]['Disabled Reason'])
 
         # Test volume service set --disable and --disable-reason
         disable_reason = 'disable_reason'
diff --git a/openstackclient/tests/functional/volume/v2/test_service.py b/openstackclient/tests/functional/volume/v2/test_service.py
index 8d1944e404..6986fde69b 100644
--- a/openstackclient/tests/functional/volume/v2/test_service.py
+++ b/openstackclient/tests/functional/volume/v2/test_service.py
@@ -64,8 +64,7 @@ class VolumeServiceTests(common.BaseVolumeTests):
             'enabled',
             cmd_output[0]['Status']
         )
-        self.assertEqual(
-            None,
+        self.assertIsNone(
             cmd_output[0]['Disabled Reason']
         )
 
diff --git a/tox.ini b/tox.ini
index ac5c6593fe..0f22650a9a 100644
--- a/tox.ini
+++ b/tox.ini
@@ -85,6 +85,8 @@ commands = sphinx-build -a -E -W -d releasenotes/build/doctrees -b html releasen
 
 [flake8]
 show-source = True
+# H203: Use assertIs(Not)None to check for None
+enable-extensions = H203
 exclude = .git,.tox,dist,doc,*lib/python*,*egg,build,tools
 # If 'ignore' is not set there are default errors and warnings that are set
 # Doc: http://flake8.readthedocs.org/en/latest/config.html#default