> ## Documentation Index
> Fetch the complete documentation index at: https://docs.elumenta.ru/llms.txt
> Use this file to discover all available pages before exploring further.

# Apply Promo Code

> Redeem a promo or referral code

```bash theme={null}
curl -X POST https://elumenta.ru/api/v2/payments/promo \
  -H "Authorization: Bearer nb_YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"code": "WELCOME2026"}'
```

Returns the bonus amount and updated balance on success.