diff --git a/app/__init__.py b/app/__init__.py
index e040868a2..d3732e208 100644
--- a/app/__init__.py
+++ b/app/__init__.py
@@ -228,6 +228,8 @@ def init_app(application):
             'asset_url': asset_fingerprinter.get_url
         }
 
+    application.url_map.converters['uuid'].to_python = lambda self, value: value
+
 
 def convert_to_boolean(value):
     if isinstance(value, string_types):
diff --git a/app/main/views/send.py b/app/main/views/send.py
index c3415c78b..a4caac031 100644
--- a/app/main/views/send.py
+++ b/app/main/views/send.py
@@ -630,7 +630,7 @@ def check_messages(service_id, template_id, upload_id, row_index=2):
 
     metadata_kwargs = {
         'notification_count': data['count_of_recipients'],
-        'template_id': str(template_id),
+        'template_id': template_id,
         'valid': True,
         'original_file_name': unicode_truncate(
             data['original_file_name'],
diff --git a/app/main/views/templates.py b/app/main/views/templates.py
index 7e8fc6019..3728e0330 100644
--- a/app/main/views/templates.py
+++ b/app/main/views/templates.py
@@ -369,7 +369,7 @@ def copy_template(service_id, template_id):
 
     current_user.belongs_to_service_or_403(from_service)
 
-    template = service_api_client.get_service_template(from_service, str(template_id))['data']
+    template = service_api_client.get_service_template(from_service, template_id)['data']
 
     template_folder = template_folder_api_client.get_template_folder(from_service, template['folder'])
     if not current_user.has_template_folder_permission(template_folder):
diff --git a/app/models/organisation.py b/app/models/organisation.py
index 27a0fe77b..966dce9bb 100644
--- a/app/models/organisation.py
+++ b/app/models/organisation.py
@@ -194,7 +194,7 @@ class Organisation(JSONModel):
 
     def associate_service(self, service_id):
         organisations_client.update_service_organisation(
-            str(service_id),
+            service_id,
             self.id
         )
 
diff --git a/app/models/service.py b/app/models/service.py
index bf989cfeb..d3bc3e79e 100644
--- a/app/models/service.py
+++ b/app/models/service.py
@@ -176,7 +176,7 @@ class Service(JSONModel):
         ]
 
     def get_template(self, template_id, version=None):
-        return service_api_client.get_service_template(self.id, str(template_id), version)['data']
+        return service_api_client.get_service_template(self.id, template_id, version)['data']
 
     def get_template_folder_with_user_permission_or_403(self, folder_id, user):
         template_folder = self.get_template_folder(folder_id)
diff --git a/app/models/user.py b/app/models/user.py
index 2c9cf5fce..61674ce30 100644
--- a/app/models/user.py
+++ b/app/models/user.py
@@ -234,7 +234,7 @@ class User(JSONModel, UserMixin):
         ]
 
     def belongs_to_service(self, service_id):
-        return str(service_id) in self.service_ids
+        return service_id in self.service_ids
 
     def belongs_to_service_or_403(self, service_id):
         if not self.belongs_to_service(service_id):
diff --git a/app/notify_client/invite_api_client.py b/app/notify_client/invite_api_client.py
index 2da6f0cdd..e44ba506a 100644
--- a/app/notify_client/invite_api_client.py
+++ b/app/notify_client/invite_api_client.py
@@ -20,7 +20,7 @@ class InviteApiClient(NotifyAdminAPIClient):
                       auth_type,
                       folder_permissions):
         data = {
-            'service': str(service_id),
+            'service': service_id,
             'email_address': email_address,
             'from_user': invite_from_id,
             'permissions': ','.join(sorted(translate_permissions_from_admin_roles_to_db(permissions))),