diff --git a/tests/app/service/send_notification/test_send_notification.py b/tests/app/service/send_notification/test_send_notification.py
index 74db646a0..e940dfe54 100644
--- a/tests/app/service/send_notification/test_send_notification.py
+++ b/tests/app/service/send_notification/test_send_notification.py
@@ -99,7 +99,7 @@ def test_send_notification_invalid_template_id(
     with notify_api.test_request_context():
         with notify_api.test_client() as client:
             mocked = mocker.patch(
-                "app.celery.provider_tasks.deliver_{}.apply_async".format(template_type)
+                f"app.celery.provider_tasks.deliver_{template_type}.apply_async"
             )
 
             data = {"to": to, "template": fake_uuid}
@@ -108,7 +108,7 @@ def test_send_notification_invalid_template_id(
             )
 
             response = client.post(
-                path="/notifications/{}".format(template_type),
+                path=f"/notifications/{template_type}",
                 data=json.dumps(data),
                 headers=[("Content-Type", "application/json"), auth_header],
             )
@@ -653,7 +653,7 @@ def test_should_send_sms_to_anyone_with_test_key(
         data=json.dumps(data),
         headers=[
             ("Content-Type", "application/json"),
-            ("Authorization", "Bearer {}".format(auth_header)),
+            ("Authorization", f"Bearer {auth_header}"),
         ],
     )
     app.celery.provider_tasks.deliver_sms.apply_async.assert_called_once_with(
@@ -691,7 +691,7 @@ def test_should_send_email_to_anyone_with_test_key(
         data=json.dumps(data),
         headers=[
             ("Content-Type", "application/json"),
-            ("Authorization", "Bearer {}".format(auth_header)),
+            ("Authorization", f"Bearer {auth_header}"),
         ],
     )
 
@@ -756,7 +756,7 @@ def test_should_persist_notification(
     queue_name,
 ):
     mocked = mocker.patch(
-        "app.celery.provider_tasks.deliver_{}.apply_async".format(template_type)
+        f"app.celery.provider_tasks.deliver_{template_type}.apply_async"
     )
     mocker.patch(
         "app.notifications.process_notifications.uuid.uuid4", return_value=fake_uuid
@@ -843,11 +843,11 @@ def test_should_delete_notification_and_return_error_if_redis_fails(
 
     with pytest.raises(expected_exception=Exception) as e:
         client.post(
-            path="/notifications/{}".format(template_type),
+            path=f"/notifications/{template_type}",
             data=json.dumps(data),
             headers=[
                 ("Content-Type", "application/json"),
-                ("Authorization", "Bearer {}".format(auth_header)),
+                ("Authorization", f"Bearer {auth_header}"),
             ],
         )
     assert str(e.value) == "failed to talk to redis"
@@ -926,7 +926,7 @@ def test_should_not_send_notification_to_non_guest_list_recipient_in_trial_mode(
     service.message_limit = 2
 
     apply_async = mocker.patch(
-        "app.celery.provider_tasks.deliver_{}.apply_async".format(notification_type)
+        f"app.celery.provider_tasks.deliver_{notification_type}.apply_async"
     )
     template = create_template(service, template_type=notification_type)
     assert sample_service_guest_list.service_id == service.id
@@ -946,7 +946,7 @@ def test_should_not_send_notification_to_non_guest_list_recipient_in_trial_mode(
         data=json.dumps(data),
         headers=[
             ("Content-Type", "application/json"),
-            ("Authorization", "Bearer {}".format(auth_header)),
+            ("Authorization", f"Bearer {auth_header}"),
         ],
     )
 
@@ -989,7 +989,7 @@ def test_should_send_notification_to_guest_list_recipient(
     sample_service.restricted = service_restricted
 
     apply_async = mocker.patch(
-        "app.celery.provider_tasks.deliver_{}.apply_async".format(notification_type)
+        f"app.celery.provider_tasks.deliver_{notification_type}.apply_async"
     )
     template = create_template(sample_service, template_type=notification_type)
     if notification_type == NotificationType.SMS:
@@ -1016,7 +1016,7 @@ def test_should_send_notification_to_guest_list_recipient(
         data=json.dumps(data),
         headers=[
             ("Content-Type", "application/json"),
-            ("Authorization", "Bearer {}".format(auth_header)),
+            ("Authorization", f"Bearer {auth_header}"),
         ],
     )
 
@@ -1119,7 +1119,14 @@ def test_create_template_raises_invalid_request_when_content_too_large(
 
 
 @pytest.mark.parametrize(
-    "notification_type, send_to", [("sms", "2028675309"), ("email", "sample@email.com")]
+    "notification_type,send_to",
+    [
+        (NotificationType.SMS, "2028675309"),
+        (
+            NotificationType.EMAIL,
+            "sample@email.com",
+        ),
+    ],
 )
 def test_send_notification_uses_priority_queue_when_template_is_marked_as_priority(
     client,
@@ -1132,7 +1139,7 @@ def test_send_notification_uses_priority_queue_when_template_is_marked_as_priori
         sample_service, template_type=notification_type, process_type="priority"
     )
     mocked = mocker.patch(
-        "app.celery.provider_tasks.deliver_{}.apply_async".format(notification_type)
+        f"app.celery.provider_tasks.deliver_{notification_type}.apply_async"
     )
 
     data = {"to": send_to, "template": str(sample.id)}
@@ -1140,7 +1147,7 @@ def test_send_notification_uses_priority_queue_when_template_is_marked_as_priori
     auth_header = create_service_authorization_header(service_id=sample.service_id)
 
     response = client.post(
-        path="/notifications/{}".format(notification_type),
+        path=f"/notifications/{notification_type}",
         data=json.dumps(data),
         headers=[("Content-Type", "application/json"), auth_header],
     )
@@ -1153,7 +1160,14 @@ def test_send_notification_uses_priority_queue_when_template_is_marked_as_priori
 
 
 @pytest.mark.parametrize(
-    "notification_type, send_to", [("sms", "2028675309"), ("email", "sample@email.com")]
+    "notification_type, send_to",
+    [
+        (NotificationType.SMS, "2028675309"),
+        (
+            NotificationType.EMAIL,
+            "sample@email.com",
+        ),
+    ],
 )
 def test_returns_a_429_limit_exceeded_if_rate_limit_exceeded(
     client, sample_service, mocker, notification_type, send_to
@@ -1172,7 +1186,7 @@ def test_returns_a_429_limit_exceeded_if_rate_limit_exceeded(
     auth_header = create_service_authorization_header(service_id=sample.service_id)
 
     response = client.post(
-        path="/notifications/{}".format(notification_type),
+        path=f"/notifications/{notification_type}",
         data=json.dumps(data),
         headers=[("Content-Type", "application/json"), auth_header],
     )
@@ -1181,9 +1195,9 @@ def test_returns_a_429_limit_exceeded_if_rate_limit_exceeded(
     result = json.loads(response.data)["result"]
     assert response.status_code == 429
     assert result == "error"
-    assert (
-        message
-        == "Exceeded rate limit for key type TYPE of LIMIT requests per INTERVAL seconds"
+    assert message == (
+        "Exceeded rate limit for key type TYPE of LIMIT "
+        "requests per INTERVAL seconds"
     )
 
     assert not persist_mock.called
@@ -1332,7 +1346,7 @@ def test_should_throw_exception_if_notification_type_is_invalid(
 ):
     auth_header = create_service_authorization_header(service_id=sample_service.id)
     response = client.post(
-        path="/notifications/{}".format(notification_type),
+        path=f"/notifications/{notification_type}",
         data={},
         headers=[("Content-Type", "application/json"), auth_header],
     )
@@ -1341,14 +1355,19 @@ def test_should_throw_exception_if_notification_type_is_invalid(
 
 
 @pytest.mark.parametrize(
-    "notification_type, recipient", [("sms", "2028675309"), ("email", "test@gov.uk")]
+    "notification_type, recipient",
+    [
+        (NotificationType.SMS, "2028675309"),
+        (
+            NotificationType.EMAIL,
+            "test@gov.uk",
+        ),
+    ],
 )
 def test_post_notification_should_set_reply_to_text(
     client, sample_service, mocker, notification_type, recipient
 ):
-    mocker.patch(
-        "app.celery.provider_tasks.deliver_{}.apply_async".format(notification_type)
-    )
+    mocker.patch(f"app.celery.provider_tasks.deliver_{notification_type}.apply_async")
     template = create_template(sample_service, template_type=notification_type)
     expected_reply_to = current_app.config["FROM_NUMBER"]
     if notification_type == NotificationType.EMAIL:
@@ -1359,7 +1378,7 @@ def test_post_notification_should_set_reply_to_text(
 
     data = {"to": recipient, "template": str(template.id)}
     response = client.post(
-        "/notifications/{}".format(notification_type),
+        f"/notifications/{notification_type}",
         data=json.dumps(data),
         headers=[
             ("Content-Type", "application/json"),
diff --git a/tests/app/service/send_notification/test_send_one_off_notification.py b/tests/app/service/send_notification/test_send_one_off_notification.py
index 9e342369d..231b42be0 100644
--- a/tests/app/service/send_notification/test_send_one_off_notification.py
+++ b/tests/app/service/send_notification/test_send_one_off_notification.py
@@ -11,6 +11,7 @@ from app.enums import (
     KeyType,
     NotificationType,
     RecipientType,
+    ServicePermissionType,
     TemplateProcessType,
     TemplateType,
 )
@@ -100,7 +101,12 @@ def test_send_one_off_notification_calls_persist_correctly_for_sms(
 def test_send_one_off_notification_calls_persist_correctly_for_international_sms(
     persist_mock, celery_mock, notify_db_session
 ):
-    service = create_service(service_permissions=["sms", "international_sms"])
+    service = create_service(
+        service_permissions=[
+            ServicePermissionType.SMS,
+            ServicePermissionType.INTERNATIONAL_SMS,
+        ],
+    )
     template = create_template(
         service=service,
         template_type=TemplateType.SMS,
diff --git a/tests/app/template/test_rest.py b/tests/app/template/test_rest.py
index 311d0e4d7..7691d8966 100644
--- a/tests/app/template/test_rest.py
+++ b/tests/app/template/test_rest.py
@@ -9,7 +9,7 @@ from freezegun import freeze_time
 from notifications_utils import SMS_CHAR_COUNT_LIMIT
 
 from app.dao.templates_dao import dao_get_template_by_id, dao_redact_template
-from app.enums import ServicePermissionType, TemplateType
+from app.enums import ServicePermissionType, TemplateProcessType, TemplateType
 from app.models import Template, TemplateHistory
 from tests import create_admin_authorization_header
 from tests.app.db import create_service, create_template, create_template_folder
@@ -39,7 +39,7 @@ def test_should_create_a_new_template_for_a_service(
     auth_header = create_admin_authorization_header()
 
     response = client.post(
-        "/service/{}/template".format(service.id),
+        f"/service/{service.id}/template",
         headers=[("Content-Type", "application/json"), auth_header],
         data=data,
     )
@@ -51,7 +51,7 @@ def test_should_create_a_new_template_for_a_service(
     assert json_resp["data"]["service"] == str(service.id)
     assert json_resp["data"]["id"]
     assert json_resp["data"]["version"] == 1
-    assert json_resp["data"]["process_type"] == "normal"
+    assert json_resp["data"]["process_type"] == TemplateProcessType.NORMAL
     assert json_resp["data"]["created_by"] == str(sample_user.id)
     if subject:
         assert json_resp["data"]["subject"] == "subject"
@@ -71,7 +71,7 @@ def test_create_a_new_template_for_a_service_adds_folder_relationship(
 
     data = {
         "name": "my template",
-        "template_type": "sms",
+        "template_type": TemplateType.SMS,
         "content": "template <b>content</b>",
         "service": str(sample_service.id),
         "created_by": str(sample_service.users[0].id),
@@ -81,7 +81,7 @@ def test_create_a_new_template_for_a_service_adds_folder_relationship(
     auth_header = create_admin_authorization_header()
 
     response = client.post(
-        "/service/{}/template".format(sample_service.id),
+        f"/service/{sample_service.id}/template",
         headers=[("Content-Type", "application/json"), auth_header],
         data=data,
     )
@@ -98,7 +98,7 @@ def test_create_template_should_return_400_if_folder_is_for_a_different_service(
 
     data = {
         "name": "my template",
-        "template_type": "sms",
+        "template_type": TemplateType.SMS,
         "content": "template <b>content</b>",
         "service": str(sample_service.id),
         "created_by": str(sample_service.users[0].id),
@@ -108,7 +108,7 @@ def test_create_template_should_return_400_if_folder_is_for_a_different_service(
     auth_header = create_admin_authorization_header()
 
     response = client.post(
-        "/service/{}/template".format(sample_service.id),
+        f"/service/{sample_service.id}/template",
         headers=[("Content-Type", "application/json"), auth_header],
         data=data,
     )
@@ -124,7 +124,7 @@ def test_create_template_should_return_400_if_folder_does_not_exist(
 ):
     data = {
         "name": "my template",
-        "template_type": "sms",
+        "template_type": TemplateType.SMS,
         "content": "template <b>content</b>",
         "service": str(sample_service.id),
         "created_by": str(sample_service.users[0].id),
@@ -134,7 +134,7 @@ def test_create_template_should_return_400_if_folder_does_not_exist(
     auth_header = create_admin_authorization_header()
 
     response = client.post(
-        "/service/{}/template".format(sample_service.id),
+        f"/service/{sample_service.id}/template",
         headers=[("Content-Type", "application/json"), auth_header],
         data=data,
     )
@@ -159,7 +159,7 @@ def test_should_raise_error_if_service_does_not_exist_on_create(
     auth_header = create_admin_authorization_header()
 
     response = client.post(
-        "/service/{}/template".format(fake_uuid),
+        f"/service/{fake_uuid}/template",
         headers=[("Content-Type", "application/json"), auth_header],
         data=data,
     )
@@ -204,7 +204,7 @@ def test_should_raise_error_on_create_if_no_permission(
     auth_header = create_admin_authorization_header()
 
     response = client.post(
-        "/service/{}/template".format(service.id),
+        f"/service/{service.id}/template",
         headers=[("Content-Type", "application/json"), auth_header],
         data=data,
     )
@@ -245,9 +245,7 @@ def test_should_be_error_on_update_if_no_permission(
     auth_header = create_admin_authorization_header()
 
     update_response = client.post(
-        "/service/{}/template/{}".format(
-            template_without_permission.service_id, template_without_permission.id
-        ),
+        f"/service/{template_without_permission.service_id}/template/{template_without_permission.id}",
         headers=[("Content-Type", "application/json"), auth_header],
         data=data,
     )
@@ -270,7 +268,7 @@ def test_should_error_if_created_by_missing(client, sample_user, sample_service)
     auth_header = create_admin_authorization_header()
 
     response = client.post(
-        "/service/{}/template".format(service_id),
+        f"/service/{service_id}/template",
         headers=[("Content-Type", "application/json"), auth_header],
         data=data,
     )
@@ -286,7 +284,7 @@ def test_should_be_error_if_service_does_not_exist_on_update(client, fake_uuid):
     auth_header = create_admin_authorization_header()
 
     response = client.post(
-        "/service/{}/template/{}".format(fake_uuid, fake_uuid),
+        f"/service/{fake_uuid}/template/{fake_uuid}",
         headers=[("Content-Type", "application/json"), auth_header],
         data=data,
     )
@@ -322,7 +320,7 @@ def test_must_have_a_subject_on_an_email_template(
 
 def test_update_should_update_a_template(client, sample_user):
     service = create_service()
-    template = create_template(service, template_type="sms")
+    template = create_template(service, template_type=TemplateType.SMS)
 
     assert template.created_by == service.created_by
     assert template.created_by != sample_user
@@ -335,7 +333,7 @@ def test_update_should_update_a_template(client, sample_user):
     auth_header = create_admin_authorization_header()
 
     update_response = client.post(
-        "/service/{}/template/{}".format(service.id, template.id),
+        f"/service/{service.id}/template/{template.id}",
         headers=[("Content-Type", "application/json"), auth_header],
         data=data,
     )
@@ -373,9 +371,7 @@ def test_should_be_able_to_archive_template(client, sample_template):
     auth_header = create_admin_authorization_header()
 
     resp = client.post(
-        "/service/{}/template/{}".format(
-            sample_template.service.id, sample_template.id
-        ),
+        f"/service/{sample_template.service.id}/template/{sample_template.id}",
         headers=[("Content-Type", "application/json"), auth_header],
         data=json_data,
     )
@@ -431,14 +427,14 @@ def test_should_be_able_to_get_all_templates_for_a_service(
     data_2 = json.dumps(data)
     auth_header = create_admin_authorization_header()
     client.post(
-        "/service/{}/template".format(sample_service.id),
+        f"/service/{sample_service.id}/template",
         headers=[("Content-Type", "application/json"), auth_header],
         data=data_1,
     )
     auth_header = create_admin_authorization_header()
 
     client.post(
-        "/service/{}/template".format(sample_service.id),
+        f"/service/{sample_service.id}/template",
         headers=[("Content-Type", "application/json"), auth_header],
         data=data_2,
     )
@@ -446,7 +442,7 @@ def test_should_be_able_to_get_all_templates_for_a_service(
     auth_header = create_admin_authorization_header()
 
     response = client.get(
-        "/service/{}/template".format(sample_service.id), headers=[auth_header]
+        f"/service/{sample_service.id}/template", headers=[auth_header]
     )
 
     assert response.status_code == 200
@@ -467,10 +463,12 @@ def test_should_get_only_templates_for_that_service(admin_request, notify_db_ses
     id_3 = create_template(service_2).id
 
     json_resp_1 = admin_request.get(
-        "template.get_all_templates_for_service", service_id=service_1.id
+        "template.get_all_templates_for_service",
+        service_id=service_1.id,
     )
     json_resp_2 = admin_request.get(
-        "template.get_all_templates_for_service", service_id=service_2.id
+        "template.get_all_templates_for_service",
+        service_id=service_2.id,
     )
 
     assert {template["id"] for template in json_resp_1["data"]} == {
@@ -580,7 +578,7 @@ def test_should_get_a_single_template(
     )
 
     response = client.get(
-        "/service/{}/template/{}".format(sample_service.id, template.id),
+        f"/service/{sample_service.id}/template/{template.id}",
         headers=[create_admin_authorization_header()],
     )
 
@@ -667,7 +665,7 @@ def test_should_return_empty_array_if_no_templates_for_service(client, sample_se
     auth_header = create_admin_authorization_header()
 
     response = client.get(
-        "/service/{}/template".format(sample_service.id), headers=[auth_header]
+        f"/service/{sample_service.id}/template", headers=[auth_header]
     )
 
     assert response.status_code == 200
@@ -681,7 +679,7 @@ def test_should_return_404_if_no_templates_for_service_with_id(
     auth_header = create_admin_authorization_header()
 
     response = client.get(
-        "/service/{}/template/{}".format(sample_service.id, fake_uuid),
+        f"/service/{sample_service.id}/template/{fake_uuid}",
         headers=[auth_header],
     )
 
@@ -715,7 +713,7 @@ def test_create_400_for_over_limit_content(
     auth_header = create_admin_authorization_header()
 
     response = client.post(
-        "/service/{}/template".format(sample_service.id),
+        f"/service/{sample_service.id}/template",
         headers=[("Content-Type", "application/json"), auth_header],
         data=data,
     )
@@ -740,9 +738,7 @@ def test_update_400_for_over_limit_content(
     )
     auth_header = create_admin_authorization_header()
     resp = client.post(
-        "/service/{}/template/{}".format(
-            sample_template.service.id, sample_template.id
-        ),
+        f"/service/{sample_template.service.id}/template/{sample_template.id}",
         headers=[("Content-Type", "application/json"), auth_header],
         data=json_data,
     )
@@ -766,9 +762,7 @@ def test_should_return_all_template_versions_for_service_and_template_id(
 
     auth_header = create_admin_authorization_header()
     resp = client.get(
-        "/service/{}/template/{}/versions".format(
-            sample_template.service_id, sample_template.id
-        ),
+        f"/service/{sample_template.service_id}/template/{sample_template.id}/versions",
         headers=[("Content-Type", "application/json"), auth_header],
     )
     assert resp.status_code == 200
@@ -792,9 +786,7 @@ def test_update_does_not_create_new_version_when_there_is_no_change(
         "content": sample_template.content,
     }
     resp = client.post(
-        "/service/{}/template/{}".format(
-            sample_template.service_id, sample_template.id
-        ),
+        f"/service/{sample_template.service_id}/template/{sample_template.id}",
         data=json.dumps(data),
         headers=[("Content-Type", "application/json"), auth_header],
     )
@@ -808,9 +800,7 @@ def test_update_set_process_type_on_template(client, sample_template):
     auth_header = create_admin_authorization_header()
     data = {"process_type": "priority"}
     resp = client.post(
-        "/service/{}/template/{}".format(
-            sample_template.service_id, sample_template.id
-        ),
+        f"/service/{sample_template.service_id}/template/{sample_template.id}",
         data=json.dumps(data),
         headers=[("Content-Type", "application/json"), auth_header],
     )
diff --git a/tests/app/template_statistics/test_rest.py b/tests/app/template_statistics/test_rest.py
index 9148839be..be6b368ab 100644
--- a/tests/app/template_statistics/test_rest.py
+++ b/tests/app/template_statistics/test_rest.py
@@ -5,6 +5,7 @@ from unittest.mock import Mock
 import pytest
 from freezegun import freeze_time
 
+from app.enums import NotificationStatus, TemplateType
 from app.utils import DATETIME_FORMAT
 from tests.app.db import create_ft_notification_status, create_notification
 
@@ -48,7 +49,7 @@ def test_get_template_statistics_for_service_by_day_returns_template_info(
     assert json_resp["data"][0]["count"] == 1
     assert json_resp["data"][0]["template_id"] == str(sample_notification.template_id)
     assert json_resp["data"][0]["template_name"] == "sms Template Name"
-    assert json_resp["data"][0]["template_type"] == "sms"
+    assert json_resp["data"][0]["template_type"] == TemplateType.SMS
 
 
 @pytest.mark.parametrize("var_name", ["limit_days", "whole_days"])
@@ -77,7 +78,7 @@ def test_get_template_statistics_for_service_by_day_goes_to_db(
                 count=3,
                 template_name=sample_template.name,
                 notification_type=sample_template.template_type,
-                status="created",
+                status=NotificationStatus.CREATED,
             )
         ],
     )
@@ -93,7 +94,7 @@ def test_get_template_statistics_for_service_by_day_goes_to_db(
             "count": 3,
             "template_name": sample_template.name,
             "template_type": sample_template.template_type,
-            "status": "created",
+            "status": NotificationStatus.CREATED,
         }
     ]
     # dao only called for 2nd, since redis returned values for first call