diff --git a/app/dao/organisation_dao.py b/app/dao/organisation_dao.py
index 9cb5a03e0..f9757664f 100644
--- a/app/dao/organisation_dao.py
+++ b/app/dao/organisation_dao.py
@@ -1,7 +1,7 @@
 from sqlalchemy.sql.expression import func
 
 from app import db
-from app.dao.dao_utils import transactional, version_class
+from app.dao.dao_utils import VersionOptions, transactional, version_class
 from app.models import (
     Organisation,
     Domain,
@@ -77,18 +77,27 @@ def dao_update_organisation(organisation_id, **kwargs):
             for domain in domains
         ])
 
+    organisation = Organisation.query.get(organisation_id)
+
     if 'organisation_type' in kwargs:
-        organisation = Organisation.query.get(organisation_id)
-        if organisation.services:
-            _update_org_type_for_organisation_services(organisation)
+        _update_organisation_services(organisation, 'organisation_type', only_where_none=False)
+
+    if 'email_branding_id' in kwargs:
+        _update_organisation_services(organisation, 'email_branding')
+
+    if 'letter_branding_id' in kwargs:
+        _update_organisation_services(organisation, 'letter_branding')
 
     return num_updated
 
 
-@version_class(Service)
-def _update_org_type_for_organisation_services(organisation):
+@version_class(
+    VersionOptions(Service, must_write_history=False),
+)
+def _update_organisation_services(organisation, attribute, only_where_none=True):
     for service in organisation.services:
-        service.organisation_type = organisation.organisation_type
+        if getattr(service, attribute) is None or not only_where_none:
+            setattr(service, attribute, getattr(organisation, attribute))
         db.session.add(service)
 
 
diff --git a/tests/app/dao/test_organisation_dao.py b/tests/app/dao/test_organisation_dao.py
index aae0b3e61..cbe10267b 100644
--- a/tests/app/dao/test_organisation_dao.py
+++ b/tests/app/dao/test_organisation_dao.py
@@ -119,12 +119,17 @@ def test_update_organisation_domains_lowercases(
     assert {domain.domain for domain in organisation.domains} == expected_domains
 
 
-def test_update_organisation_does_not_update_the_service_org_type_if_org_type_is_not_provided(
+def test_update_organisation_does_not_update_the_service_if_certain_attributes_not_provided(
     sample_service,
     sample_organisation,
 ):
+    email_branding = create_email_branding()
+    letter_branding = create_letter_branding()
+
     sample_service.organisation_type = 'local'
     sample_organisation.organisation_type = 'central'
+    sample_organisation.email_branding = email_branding
+    sample_organisation.letter_branding = letter_branding
 
     sample_organisation.services.append(sample_service)
     db.session.commit()
@@ -134,8 +139,16 @@ def test_update_organisation_does_not_update_the_service_org_type_if_org_type_is
     dao_update_organisation(sample_organisation.id, name='updated org name')
 
     assert sample_organisation.name == 'updated org name'
+
+    assert sample_organisation.organisation_type == 'central'
     assert sample_service.organisation_type == 'local'
 
+    assert sample_organisation.email_branding == email_branding
+    assert sample_service.email_branding is None
+
+    assert sample_organisation.letter_branding == letter_branding
+    assert sample_service.letter_branding is None
+
 
 def test_update_organisation_updates_the_service_org_type_if_org_type_is_provided(
     sample_service,
@@ -157,6 +170,49 @@ def test_update_organisation_updates_the_service_org_type_if_org_type_is_provide
     ).one().organisation_type == 'central'
 
 
+def test_update_organisation_updates_the_service_branding_if_branding_is_provided(
+    sample_service,
+    sample_organisation,
+):
+    email_branding = create_email_branding()
+    letter_branding = create_letter_branding()
+
+    sample_organisation.services.append(sample_service)
+    db.session.commit()
+
+    dao_update_organisation(sample_organisation.id, email_branding_id=email_branding.id)
+    dao_update_organisation(sample_organisation.id, letter_branding_id=letter_branding.id)
+
+    assert sample_organisation.email_branding == email_branding
+    assert sample_organisation.letter_branding == letter_branding
+    assert sample_service.email_branding == email_branding
+    assert sample_service.letter_branding == letter_branding
+
+
+def test_update_organisation_does_not_override_service_branding(
+    sample_service,
+    sample_organisation,
+):
+    email_branding = create_email_branding()
+    custom_email_branding = create_email_branding(name='custom')
+    letter_branding = create_letter_branding()
+    custom_letter_branding = create_letter_branding(name='custom', filename='custom')
+
+    sample_service.email_branding = custom_email_branding
+    sample_service.letter_branding = custom_letter_branding
+
+    sample_organisation.services.append(sample_service)
+    db.session.commit()
+
+    dao_update_organisation(sample_organisation.id, email_branding_id=email_branding.id)
+    dao_update_organisation(sample_organisation.id, letter_branding_id=letter_branding.id)
+
+    assert sample_organisation.email_branding == email_branding
+    assert sample_organisation.letter_branding == letter_branding
+    assert sample_service.email_branding == custom_email_branding
+    assert sample_service.letter_branding == custom_letter_branding
+
+
 def test_add_service_to_organisation(sample_service, sample_organisation):
     assert sample_organisation.services == []