diff --git a/app/schemas.py b/app/schemas.py
index 41d487608..f8b510f7b 100644
--- a/app/schemas.py
+++ b/app/schemas.py
@@ -25,7 +25,7 @@ from notifications_utils.recipients import (
 
 from app import ma
 from app import models
-from app.models import ServicePermission
+from app.models import ServicePermission, BROADCAST_TYPE
 from app.dao.permissions_dao import permission_dao
 from app.utils import DATETIME_FORMAT_NO_TIMEZONE, get_template_instance
 
@@ -242,7 +242,14 @@ class ServiceSchema(BaseSchema, UUIDsAsStringsMixin):
         return service.allowed_broadcast_provider
 
     def _get_broadcast_channel(self, service):
-        return service.broadcast_channel
+        # TODO: Once we've migrated data so that all broadcast services have `service.broadcast_channel`
+        # set then we can remove this logic and related tests and instead just return
+        # `service.broadcast_channel`. For the moment though, as we have some services with the broadcast
+        # permission that do not have a row in the service_broadcast_settings table, we need to hardcode
+        # this in here to give them a default that the admin app can use
+        if BROADCAST_TYPE in self.service_permissions(service):
+            return service.broadcast_channel if service.broadcast_channel else "test"
+        return None
 
     def get_letter_logo_filename(self, service):
         return service.letter_branding and service.letter_branding.filename
diff --git a/tests/app/service/test_rest.py b/tests/app/service/test_rest.py
index 128afb392..88a714349 100644
--- a/tests/app/service/test_rest.py
+++ b/tests/app/service/test_rest.py
@@ -292,6 +292,38 @@ def test_get_service_by_id_returns_allowed_broadcast_provider(notify_db, admin_r
     assert json_resp['data']['allowed_broadcast_provider'] == 'ee'
 
 
+def test_get_service_by_id_for_broadcast_service_takes_channel_from_service_broadcast_settings(
+    admin_request, sample_broadcast_service
+):
+    assert sample_broadcast_service.broadcast_channel == 'severe'
+
+    json_resp = admin_request.get('service.get_service_by_id', service_id=sample_broadcast_service.id)
+    assert json_resp['data']['id'] == str(sample_broadcast_service.id)
+    assert json_resp['data']['broadcast_channel'] == 'severe'
+
+
+def test_get_service_by_id_for_service_with_broadcast_permission_sets_channel_as_test_if_no_service_broadcast_settings(
+    admin_request, notify_db_session
+):
+    service = create_service(service_permissions=[BROADCAST_TYPE])
+    assert BROADCAST_TYPE in [p.permission for p in service.permissions]
+    assert service.broadcast_channel == None
+
+    json_resp = admin_request.get('service.get_service_by_id', service_id=service.id)
+    assert json_resp['data']['id'] == str(service.id)
+    assert json_resp['data']['broadcast_channel'] == 'test'
+
+
+def test_get_service_by_id_for_non_broadcast_service_sets_channel_as_none(
+    admin_request, sample_service
+):
+    assert BROADCAST_TYPE not in [p.permission for p in sample_service.permissions]
+
+    json_resp = admin_request.get('service.get_service_by_id', service_id=sample_service.id)
+    assert json_resp['data']['id'] == str(sample_service.id)
+    assert json_resp['data']['broadcast_channel'] == None
+
+
 @pytest.mark.parametrize('detailed', [True, False])
 def test_get_service_by_id_returns_organisation_type(admin_request, sample_service, detailed):
     json_resp = admin_request.get('service.get_service_by_id', service_id=sample_service.id, detailed=detailed)