diff --git a/app/utils/branding.py b/app/utils/branding.py
index 121366e2e..7ecf8ef95 100644
--- a/app/utils/branding.py
+++ b/app/utils/branding.py
@@ -6,26 +6,25 @@ NHS_EMAIL_BRANDING_ID = 'a7dc4e56-660b-4db7-8cff-12c37b12b5ea'
 
 def get_email_choices(service):
     organisation_branding_id = service.organisation.email_branding_id if service.organisation else None
-    service_branding_id = service.email_branding_id
 
     if (
         service.organisation_type == Organisation.TYPE_CENTRAL
-        and organisation_branding_id is None
-        and service_branding_id is not None
+        and service.email_branding_id is not None  # GOV.UK is not current branding
+        and organisation_branding_id is None  # no default to supersede it (GOV.UK)
     ):
         yield ('govuk', 'GOV.UK')
 
     if (
         service.organisation_type == Organisation.TYPE_CENTRAL
         and service.organisation
-        and organisation_branding_id is None
-        and service.email_branding_name.lower() != 'GOV.UK and {}'.format(service.organisation.name).lower()
+        and organisation_branding_id is None  # don't offer both if org has default
+        and service.email_branding_name.lower() != f'GOV.UK and {service.organisation.name}'.lower()
     ):
-        yield ('govuk_and_org', 'GOV.UK and {}'.format(service.organisation.name))
+        yield ('govuk_and_org', f'GOV.UK and {service.organisation.name}')
 
     if (
         service.organisation_type in NHS_TYPES
-        and service_branding_id != NHS_EMAIL_BRANDING_ID
+        and service.email_branding_id != NHS_EMAIL_BRANDING_ID
     ):
         yield ('nhs', 'NHS')
 
@@ -33,8 +32,8 @@ def get_email_choices(service):
         service.organisation
         and service.organisation_type not in NHS_TYPES
         and (
-            service_branding_id is None
-            or service_branding_id != organisation_branding_id
+            service.email_branding_id is None  # GOV.UK is current branding
+            or service.email_branding_id != organisation_branding_id
         )
     ):
         yield ('organisation', service.organisation.name)
@@ -42,7 +41,6 @@ def get_email_choices(service):
 
 def get_letter_choices(service):
     organisation_branding_id = service.organisation.letter_branding_id if service.organisation else None
-    service_branding_id = service.letter_branding_id
 
     if (
         service.organisation_type in NHS_TYPES
@@ -54,8 +52,8 @@ def get_letter_choices(service):
         service.organisation
         and service.organisation_type not in NHS_TYPES
         and (
-            service_branding_id is None
-            or service_branding_id != organisation_branding_id
+            service.letter_branding_id is None  # GOV.UK is current branding
+            or service.letter_branding_id != organisation_branding_id
         )
     ):
         yield ('organisation', service.organisation.name)