diff --git a/app/service/rest.py b/app/service/rest.py
index 04fcfc661..c10b3437a 100644
--- a/app/service/rest.py
+++ b/app/service/rest.py
@@ -458,26 +458,6 @@ def get_notification_for_service(service_id, notification_id):
     ), 200
 
 
-# TODO: possibly unnecessary after removing letters
-@service_blueprint.route('/<uuid:service_id>/notifications/<uuid:notification_id>/cancel', methods=['POST'])
-def cancel_notification_for_service(service_id, notification_id):
-    notification = notifications_dao.get_notification_by_id(notification_id, service_id)
-
-    if not notification:
-        raise InvalidRequest('Notification not found', status_code=404)
-    else:
-        raise InvalidRequest('Notification cannot be cancelled - only letters can be cancelled', status_code=400)
-
-    updated_notification = notifications_dao.update_notification_status_by_id(
-        notification_id,
-        NOTIFICATION_CANCELLED,
-    )
-
-    return jsonify(
-        notification_with_template_schema.dump(updated_notification)
-    ), 200
-
-
 def search_for_notification_by_to_field(service_id, search_term, statuses, notification_type):
     results = notifications_dao.dao_get_notifications_by_recipient_or_reference(
         service_id=service_id,
diff --git a/tests/app/service/test_rest.py b/tests/app/service/test_rest.py
index 25c05e3df..3f9c98563 100644
--- a/tests/app/service/test_rest.py
+++ b/tests/app/service/test_rest.py
@@ -3006,35 +3006,6 @@ def test_get_organisation_for_service_id_return_empty_dict_if_service_not_in_org
     assert response == {}
 
 
-def test_cancel_notification_for_service_raises_invalid_request_when_notification_is_not_found(
-    admin_request,
-    sample_service,
-    fake_uuid,
-):
-    response = admin_request.post(
-        'service.cancel_notification_for_service',
-        service_id=sample_service.id,
-        notification_id=fake_uuid,
-        _expected_status=404
-    )
-    assert response['message'] == 'Notification not found'
-    assert response['result'] == 'error'
-
-
-def test_cancel_notification_for_service_raises_invalid_request_when_notification_is_not_a_letter(
-    admin_request,
-    sample_notification,
-):
-    response = admin_request.post(
-        'service.cancel_notification_for_service',
-        service_id=sample_notification.service_id,
-        notification_id=sample_notification.id,
-        _expected_status=400
-    )
-    assert response['message'] == 'Notification cannot be cancelled - only letters can be cancelled'
-    assert response['result'] == 'error'
-
-
 def test_get_monthly_notification_data_by_service(sample_service, admin_request):
     create_ft_notification_status(date(2019, 4, 17), notification_type='sms', service=sample_service,
                                   notification_status='delivered')