diff --git a/h/services/group_create.py b/h/services/group_create.py
index fbf9305ba6f..5a53a793680 100644
--- a/h/services/group_create.py
+++ b/h/services/group_create.py
@@ -1,7 +1,7 @@
 from functools import partial
 
 from h import session
-from h.models import Group, GroupScope
+from h.models import Group, GroupMembership, GroupScope
 from h.models.group import GROUP_TYPE_FLAGS
 
 
@@ -126,7 +126,9 @@ def _create(self, name, userid, type_flags, scopes, **kwargs):
         # self.publish() or `return group`.
         self.db.flush()
 
-        group.members.append(group.creator)
+        self.db.add(
+            GroupMembership(user_id=creator.id, group_id=group.id, roles=["owner"])
+        )
         self.publish("group-join", group.pubid, group.creator.userid)
 
         return group
diff --git a/tests/unit/h/services/group_create_test.py b/tests/unit/h/services/group_create_test.py
index e6e2c5c8733..3cccd7d9a76 100644
--- a/tests/unit/h/services/group_create_test.py
+++ b/tests/unit/h/services/group_create_test.py
@@ -2,8 +2,9 @@
 
 import pytest
 from h_matchers import Any
+from sqlalchemy import select
 
-from h.models import Group, GroupScope, User
+from h.models import Group, GroupMembership, GroupScope, User
 from h.models.group import JoinableBy, ReadableBy, WriteableBy
 from h.services.group_create import GroupCreateService, group_create_factory
 from tests.common.matchers import Matcher
@@ -51,10 +52,12 @@ def test_it_skips_setting_description_when_missing(self, svc, creator):
 
         assert group.description is None
 
-    def test_it_adds_group_creator_to_members(self, svc, creator):
+    def test_it_adds_group_creator_to_members_as_owner(self, svc, creator, db_session):
         group = svc.create_private_group("Anteater fans", creator.userid)
 
-        assert creator in group.members
+        assert db_session.scalar(
+            select(GroupMembership).where(GroupMembership.group_id == group.id)
+        ).roles == ["owner"]
 
     @pytest.mark.parametrize(
         "flag,expected_value",
@@ -167,10 +170,14 @@ def test_it_sets_group_creator(self, svc, creator, origins):
 
         assert group.creator == creator
 
-    def test_it_adds_group_creator_to_members(self, svc, creator, origins):
+    def test_it_adds_group_creator_to_members_as_owner(
+        self, svc, creator, origins, db_session
+    ):
         group = svc.create_open_group("Anteater fans", creator.userid, scopes=origins)
 
-        assert creator in group.members
+        assert db_session.scalar(
+            select(GroupMembership).where(GroupMembership.group_id == group.id)
+        ).roles == ["owner"]
 
     @pytest.mark.parametrize(
         "flag,expected_value",
@@ -327,12 +334,16 @@ def test_it_sets_group_creator(self, svc, creator, origins):
 
         assert group.creator == creator
 
-    def test_it_adds_group_creator_to_members(self, svc, creator, origins):
+    def test_it_adds_group_creator_to_members_as_owner(
+        self, svc, creator, origins, db_session
+    ):
         group = svc.create_restricted_group(
             "Anteater fans", creator.userid, scopes=origins
         )
 
-        assert creator in group.members
+        assert db_session.scalar(
+            select(GroupMembership).where(GroupMembership.group_id == group.id)
+        ).roles == ["owner"]
 
     @pytest.mark.parametrize(
         "flag,expected_value",