diff --git a/app/v2/broadcast/post_broadcast.py b/app/v2/broadcast/post_broadcast.py
index 54acfaf72..c76c4dfde 100644
--- a/app/v2/broadcast/post_broadcast.py
+++ b/app/v2/broadcast/post_broadcast.py
@@ -5,7 +5,7 @@ from notifications_utils.polygons import Polygons
 from notifications_utils.template import BroadcastMessageTemplate
 from sqlalchemy.orm.exc import MultipleResultsFound
 
-from app import api_user, authenticated_service
+from app import api_user, authenticated_service, redis_store
 from app.broadcast_message.translators import cap_xml_to_dict
 from app.broadcast_message.utils import (
     validate_and_update_broadcast_message_status,
@@ -126,6 +126,9 @@ def _cancel_or_reject_broadcast(references_to_original_broadcast, service_id):
         new_status,
         api_key_id=api_user.id
     )
+    redis_store.delete(
+        f'service-{broadcast_message.service_id}-broadcast-message-{broadcast_message.id}'
+    )
     return broadcast_message
 
 
diff --git a/tests/app/v2/broadcast/test_post_broadcast.py b/tests/app/v2/broadcast/test_post_broadcast.py
index 16b81e82c..9b6c56d5a 100644
--- a/tests/app/v2/broadcast/test_post_broadcast.py
+++ b/tests/app/v2/broadcast/test_post_broadcast.py
@@ -134,6 +134,8 @@ def test_valid_cancel_broadcast_request_calls_validate_and_update_broadcast_mess
     api_key = create_api_key(service=sample_broadcast_service)
     auth_header = create_service_authorization_header(service_id=sample_broadcast_service.id)
 
+    mock_redis_delete = mocker.patch('app.redis_store.delete')
+
     # create a broadcast
     response_for_create = client.post(
         path='/v2/broadcast',
@@ -165,6 +167,9 @@ def test_valid_cancel_broadcast_request_calls_validate_and_update_broadcast_mess
         expected_status,
         api_key_id=api_key.id
     )
+    mock_redis_delete.assert_called_once_with(
+        f'service-{sample_broadcast_service.id}-broadcast-message-{broadcast_message.id}'
+    )
 
 
 @pytest.mark.parametrize('cap_xml_document, expected_status, expected_error', (