diff --git a/src/lib/features/project/project-service.test.ts b/src/lib/features/project/project-service.test.ts
index 4ca7f09b58..34d9dc22e1 100644
--- a/src/lib/features/project/project-service.test.ts
+++ b/src/lib/features/project/project-service.test.ts
@@ -2,6 +2,7 @@ import { createTestConfig } from '../../../test/config/test-config';
 import { BadDataError } from '../../error';
 import { type IBaseEvent, RoleName, TEST_AUDIT_USER } from '../../types';
 import { createFakeProjectService } from './createProjectService';
+import ProjectService from './project-service';
 
 describe('enterprise extension: enable change requests', () => {
     const createService = () => {
@@ -300,4 +301,44 @@ describe('enterprise extension: enable change requests', () => {
             ),
         ).resolves.toBeTruthy();
     });
+
+    test('has at least one owner after deletion when group has the role and a project user for role exists', async () => {
+        const config = createTestConfig();
+        const projectId = 'fake-project-id';
+        const service = new ProjectService(
+            {
+                projectStore: {} as any,
+                projectOwnersReadModel: {} as any,
+                projectFlagCreatorsReadModel: {} as any,
+                eventStore: {} as any,
+                featureToggleStore: {} as any,
+                environmentStore: {} as any,
+                featureEnvironmentStore: {} as any,
+                accountStore: {} as any,
+                projectStatsStore: {} as any,
+                projectReadModel: {} as any,
+                onboardingReadModel: {} as any,
+            },
+            config,
+            {
+                getProjectUsersForRole: async () =>
+                    Promise.resolve([{ id: 1 } as any]),
+            } as any,
+            {} as any,
+            {
+                getProjectGroups: async () =>
+                    Promise.resolve([{ roles: [2, 5] } as any]),
+            } as any,
+            {} as any,
+            {} as any,
+            {} as any,
+            {} as any,
+        );
+
+        await service.validateAtLeastOneOwner(projectId, {
+            id: 5,
+            name: 'Owner',
+            type: 'Owner',
+        });
+    });
 });
diff --git a/src/lib/features/project/project-service.ts b/src/lib/features/project/project-service.ts
index a3c664b780..106866e4c7 100644
--- a/src/lib/features/project/project-service.ts
+++ b/src/lib/features/project/project-service.ts
@@ -1146,8 +1146,8 @@ export default class ProjectService {
                 projectId,
             );
             const groups = await this.groupService.getProjectGroups(projectId);
-            const roleGroups = groups.filter(
-                (g) => g.roleId === currentRole.id,
+            const roleGroups = groups.filter((g) =>
+                g.roles?.includes(currentRole.id),
             );
             if (users.length + roleGroups.length < 2) {
                 throw new ProjectWithoutOwnerError();
@@ -1264,11 +1264,11 @@ export default class ProjectService {
         auditUser: IAuditUser,
     ): Promise<void> {
         const usersWithRoles = await this.getAccessToProject(projectId);
-        const user = usersWithRoles.groups.find((u) => u.id === userId);
-        if (!user)
+        const userGroup = usersWithRoles.groups.find((u) => u.id === userId);
+        if (!userGroup)
             throw new ValidationError('Unexpected empty user', [], undefined);
-        const currentRole = usersWithRoles.roles.find(
-            (r) => r.id === user.roleId,
+        const currentRole = usersWithRoles.roles.find((r) =>
+            userGroup.roles?.includes(r.id),
         );
         if (!currentRole)
             throw new ValidationError(
diff --git a/src/lib/services/group-service.ts b/src/lib/services/group-service.ts
index f83b74cd7b..d629211ba8 100644
--- a/src/lib/services/group-service.ts
+++ b/src/lib/services/group-service.ts
@@ -2,7 +2,6 @@ import type {
     ICreateGroupModel,
     IGroup,
     IGroupModel,
-    IGroupModelWithProjectRole,
     IGroupProject,
     IGroupRole,
     IGroupUser,
@@ -29,6 +28,7 @@ import type { IAccountStore } from '../types/stores/account-store';
 import type { IUser } from '../types/user';
 import type EventService from '../features/events/event-service';
 import { SSO_SYNC_USER } from '../db/group-store';
+import type { IGroupWithProjectRoles } from '../types/stores/access-store';
 
 const setsAreEqual = (firstSet, secondSet) =>
     firstSet.size === secondSet.size &&
@@ -179,7 +179,7 @@ export class GroupService {
 
     async getProjectGroups(
         projectId: string,
-    ): Promise<IGroupModelWithProjectRole[]> {
+    ): Promise<IGroupWithProjectRoles[]> {
         const projectGroups = await this.groupStore.getProjectGroups(projectId);
 
         if (projectGroups.length > 0) {
diff --git a/src/lib/types/group.ts b/src/lib/types/group.ts
index 5dc2b7002c..a4b387b425 100644
--- a/src/lib/types/group.ts
+++ b/src/lib/types/group.ts
@@ -53,8 +53,7 @@ export interface ICreateGroupUserModel {
     user: Pick<IUser, 'id'>;
 }
 
-export interface IGroupModelWithProjectRole extends IGroupModel {
-    roleId: number;
+export interface IGroupModelWithAddedAt extends IGroupModel {
     addedAt: Date;
 }
 
diff --git a/src/lib/types/stores/access-store.ts b/src/lib/types/stores/access-store.ts
index f7bdd288ca..9d571d106a 100644
--- a/src/lib/types/stores/access-store.ts
+++ b/src/lib/types/stores/access-store.ts
@@ -1,5 +1,5 @@
 import type { PermissionRef } from '../../services/access-service';
-import type { IGroupModelWithProjectRole } from '../group';
+import type { IGroupModelWithAddedAt } from '../group';
 import type { IPermission, IUserAccessOverview, IUserWithRole } from '../model';
 import type { Store } from './store';
 
@@ -62,7 +62,7 @@ export interface IUserWithProjectRoles
     extends IUserWithRole,
         IEntityWithProjectRoles {}
 export interface IGroupWithProjectRoles
-    extends IGroupModelWithProjectRole,
+    extends IGroupModelWithAddedAt,
         IEntityWithProjectRoles {}
 
 export interface IAccessStore extends Store<IRole, number> {