# External User ID & Privacy Controls

*24.02.2026*

Track referrals by your internal user ID instead of email — and control exactly what personal data Affonso stores.

## External User ID

`Affonso.signup()` now accepts an options object with `externalUserId`, `email`, and `name`. You no longer need to pass an email address to track leads.

```javascript
// Track by internal user ID — no email required
window.Affonso.signup({
  externalUserId: 'usr_abc123'
});

// Or combine with email and name
window.Affonso.signup({
  email: 'user@example.com',
  externalUserId: 'usr_abc123',
  name: 'Jane Doe'
});
```

Pass the same ID as `userId` in your payment provider's metadata so webhook events automatically match back to referrals. Works with Stripe, Polar, Creem, Dodo, and Paddle.

The classic email-only format still works exactly as before — no changes needed for existing integrations.

## Privacy Controls

New toggles in your affiliate program settings let you control what data is stored:

- **Email tracking** — Disable to stop storing customer email addresses on referrals
- **Name tracking** — Disable to stop storing customer names on referrals

When email tracking is disabled, referrals are matched using `externalUserId` instead. Ideal for privacy-conscious setups or strict data protection requirements.

Find these settings in **Affiliate Program → Privacy Controls**.

## Learn More

- [Signup & Lead Tracking Guide](/help/installation-guides/overview/signup-tracking) — Full documentation with framework examples and best practices