diff --git a/app/inbound_number/rest.py b/app/inbound_number/rest.py
index becaf21fc..24b2445c2 100644
--- a/app/inbound_number/rest.py
+++ b/app/inbound_number/rest.py
@@ -36,6 +36,8 @@ def post_allocate_inbound_number(service_id):
     if inbound_number:
         if not inbound_number.active:
             dao_set_inbound_number_active_flag(service_id, active=True)
+            service = dao_fetch_service_by_id(service_id)
+            insert_or_update_service_sms_sender(service, inbound_number.number, inbound_number.id)
             return jsonify(), 204
         else:
             return jsonify(), 200
diff --git a/tests/app/inbound_number/test_rest.py b/tests/app/inbound_number/test_rest.py
index c237df448..3ffd691ab 100644
--- a/tests/app/inbound_number/test_rest.py
+++ b/tests/app/inbound_number/test_rest.py
@@ -114,25 +114,6 @@ def test_rest_set_inbound_number_active_flag_off(
     assert not inbound_number_from_db.active
 
 
-def test_allocate_inbound_number_insert_update_service_sms_sender(
-        admin_request, notify_db_session
-):
-    service = create_service()
-    inbound_number = create_inbound_number(number='123')
-
-    admin_request.post(
-        'inbound_number.post_allocate_inbound_number',
-        _expected_status=204,
-        service_id=service.id
-    )
-
-    service_sms_senders = ServiceSmsSender.query.all()
-    assert len(service_sms_senders) == 1
-    assert service_sms_senders[0].sms_sender == inbound_number.number
-    assert service_sms_senders[0].inbound_number_id == inbound_number.id
-    assert service_sms_senders[0].is_default
-
-
 def test_allocate_inbound_number_to_service(admin_request, notify_db_session):
     service = create_service()
     inbound_number = create_inbound_number(number='1235468')