diff --git a/src/__tests__/integration/creator-holders-sort.test.ts b/src/__tests__/integration/creator-holders-sort.test.ts
new file mode 100644
index 0000000..96eab9c
--- /dev/null
+++ b/src/__tests__/integration/creator-holders-sort.test.ts
@@ -0,0 +1,102 @@
+import supertest from 'supertest';
+import app from '../../app';
+import { prisma } from '../../utils/prisma.utils';
+
+describe('GET /api/v1/creators/:id/holders sorting', () => {
+  let creatorId: string;
+
+  beforeAll(async () => {
+    // Seed a creator
+    const user = await prisma.user.create({
+      data: {
+        id: 'holder-sort-test-user',
+        email: 'holder-sort-test@example.com',
+        passwordHash: 'dummy-hash',
+        firstName: 'Holder',
+        lastName: 'SortTest',
+      }
+    });
+
+    const creator = await prisma.creatorProfile.create({
+      data: {
+        userId: user.id,
+        handle: 'holder-sort-creator',
+        displayName: 'Holder Sort Creator',
+      }
+    });
+    creatorId = creator.id;
+
+    // Seed 3 holders with different held_since (createdAt) and key_balance
+    await prisma.keyOwnership.createMany({
+      data: [
+        {
+          ownerAddress: '0xabc1',
+          creatorId: creator.id,
+          balance: 10,
+          createdAt: new Date('2024-01-01T00:00:00.000Z'), // Earliest buyer, smallest balance
+        },
+        {
+          ownerAddress: '0xabc2',
+          creatorId: creator.id,
+          balance: 30,
+          createdAt: new Date('2024-02-01T00:00:00.000Z'), // Middle buyer, largest balance
+        },
+        {
+          ownerAddress: '0xabc3',
+          creatorId: creator.id,
+          balance: 20,
+          createdAt: new Date('2024-03-01T00:00:00.000Z'), // Latest buyer, middle balance
+        },
+      ]
+    });
+  });
+
+  afterAll(async () => {
+    await prisma.keyOwnership.deleteMany({
+      where: { creatorId }
+    });
+    await prisma.creatorProfile.delete({
+      where: { id: creatorId }
+    });
+    await prisma.user.delete({
+      where: { id: 'holder-sort-test-user' }
+    });
+    await prisma.$disconnect();
+  });
+
+  it('returns holders sorted by balance desc by default', async () => {
+    const res = await supertest(app).get(`/api/v1/creators/${creatorId}/holders`);
+    expect(res.status).toBe(200);
+
+    const items = res.body.data.items;
+    expect(items).toHaveLength(3);
+    
+    // Largest balance first: 30 (0xabc2), 20 (0xabc3), 10 (0xabc1)
+    expect(items[0].wallet_address).toBe('0xabc2');
+    expect(items[0].key_balance).toBe(30);
+    
+    expect(items[1].wallet_address).toBe('0xabc3');
+    expect(items[1].key_balance).toBe(20);
+    
+    expect(items[2].wallet_address).toBe('0xabc1');
+    expect(items[2].key_balance).toBe(10);
+  });
+
+  it('returns earliest buyer first when sort=held_since is passed', async () => {
+    const res = await supertest(app).get(`/api/v1/creators/${creatorId}/holders?sort=held_since`);
+    expect(res.status).toBe(200);
+
+    const items = res.body.data.items;
+    expect(items).toHaveLength(3);
+    
+    // Earliest buyer first: 2024-01-01 (0xabc1), 2024-02-01 (0xabc2), 2024-03-01 (0xabc3)
+    expect(items[0].wallet_address).toBe('0xabc1');
+    expect(items[0].held_since).toBe('2024-01-01T00:00:00.000Z');
+    
+    expect(items[1].wallet_address).toBe('0xabc2');
+    expect(items[1].held_since).toBe('2024-02-01T00:00:00.000Z');
+    
+    expect(items[2].wallet_address).toBe('0xabc3');
+    expect(items[2].held_since).toBe('2024-03-01T00:00:00.000Z');
+  });
+});