diff --git a/packages/backend-test-utils/src/next/services/mockCredentials.ts b/packages/backend-test-utils/src/next/services/mockCredentials.ts
index 99456e574b..231c108ac4 100644
--- a/packages/backend-test-utils/src/next/services/mockCredentials.ts
+++ b/packages/backend-test-utils/src/next/services/mockCredentials.ts
@@ -108,7 +108,7 @@ export namespace mockCredentials {
    */
   export function user(
     userEntityRef: string = DEFAULT_MOCK_USER_ENTITY_REF,
-    options?: { actor?: string },
+    options?: { actor?: { subject: string } },
   ): BackstageCredentials<BackstageUserPrincipal> {
     validateUserEntityRef(userEntityRef);
     return {
@@ -134,14 +134,14 @@ export namespace mockCredentials {
      */
     export function token(
       userEntityRef?: string,
-      options?: { actor?: string },
+      options?: { actor?: { subject: string } },
     ): string {
       if (userEntityRef) {
         validateUserEntityRef(userEntityRef);
         return `${MOCK_USER_TOKEN_PREFIX}${JSON.stringify({
           sub: userEntityRef,
           ...(options?.actor && {
-            actor: options.actor,
+            actor: { subject: options.actor.subject },
           }),
         } satisfies UserTokenPayload)}`;
       }
diff --git a/plugins/permission-backend/src/service/router.test.ts b/plugins/permission-backend/src/service/router.test.ts
index 264a19ccc3..80308d7ca7 100644
--- a/plugins/permission-backend/src/service/router.test.ts
+++ b/plugins/permission-backend/src/service/router.test.ts
@@ -596,7 +596,7 @@ describe('createRouter', () => {
         expect(mockApplyConditions).toHaveBeenCalledWith(
           'plugin-1',
           mockCredentials.user('user:default/spiderman', {
-            actor: 'some-service',
+            actor: { subject: 'some-service' },
           }),
           [
             expect.objectContaining({
@@ -611,7 +611,7 @@ describe('createRouter', () => {
         expect(mockApplyConditions).toHaveBeenCalledWith(
           'plugin-2',
           mockCredentials.user('user:default/spiderman', {
-            actor: 'some-service',
+            actor: { subject: 'some-service' },
           }),
           [
             expect.objectContaining({
@@ -729,7 +729,7 @@ describe('createRouter', () => {
 
       function userTokenIssuedByService() {
         return mockCredentials.user.token('user:default/spiderman', {
-          actor: 'some-service',
+          actor: { subject: 'some-service' },
         });
       }
     });