diff --git a/tests/app/service/send_notification/test_send_notification.py b/tests/app/service/send_notification/test_send_notification.py
index 83122dcbc..dbd8b8d85 100644
--- a/tests/app/service/send_notification/test_send_notification.py
+++ b/tests/app/service/send_notification/test_send_notification.py
@@ -169,12 +169,6 @@ def test_send_notification_with_placeholders_replaced(notify_api, sample_email_t
         ),
         '6',
     ),
-    pytest.param(
-        None,
-        ('we consider None equivalent to missing personalisation'),
-        '',
-        marks=pytest.mark.xfail
-    ),
 ])
 def test_send_notification_with_placeholders_replaced_with_unusual_types(
     client,
@@ -209,6 +203,43 @@ def test_send_notification_with_placeholders_replaced_with_unusual_types(
     assert response_data['subject'] == expected_subject
 
 
+@pytest.mark.parametrize('personalisation, expected_body, expected_subject', [
+    (
+        None,
+        ('we consider None equivalent to missing personalisation'),
+        '',
+    ),
+])
+def test_send_notification_with_placeholders_replaced_with_unusual_types_no_personalization(
+    client,
+    sample_email_template_with_placeholders,
+    mocker,
+    personalisation,
+    expected_body,
+    expected_subject,
+):
+    mocker.patch('app.celery.provider_tasks.deliver_email.apply_async')
+
+    response = client.post(
+        path='/notifications/email',
+        data=json.dumps(
+            {
+                'to': 'ok@ok.com',
+                'template': str(sample_email_template_with_placeholders.id),
+                'personalisation': {
+                    'name': personalisation
+                }
+            }
+        ),
+        headers=[
+            ('Content-Type', 'application/json'),
+            create_service_authorization_header(service_id=sample_email_template_with_placeholders.service.id)
+        ]
+    )
+
+    assert response.status_code == 400
+
+
 def test_should_not_send_notification_for_archived_template(notify_api, sample_template):
     with notify_api.test_request_context():
         with notify_api.test_client() as client: