> For the complete documentation index, see [llms.txt](https://docs.0xprocessing.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.0xprocessing.com/0xprocessing-api-v1/binance-pay.md).

# Binance Pay

Binance Pay — instant crypto payments through Binance with fast confirmation and automatic settlement to the merchant balance.

### Authorization

{% hint style="danger" %}
**Authentication Rule** The request must contain an **`APIKEY`** header with your API key. The key can be generated in the merchant dashboard under **Settings → API**.
{% endhint %}

All requests must include the following header:

```http
APIKEY: your_api_key_here
Content-Type: application/x-www-form-urlencoded
```

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### Important Notes

* **ExternalId Uniqueness**: The `ExternalId` must be unique per transaction in your system. It is used for idempotency — submitting the same `ExternalId` twice will return the existing transaction data instead of creating a duplicate.
* **txId Availability**: For on-chain withdrawals, `txId` is null while the transaction is pending. It is populated once the transaction is broadcast to the blockchain.
* **binanceId in Response**: The `binanceId` in the withdrawal response becomes available after Binance processes the request. It is null immediately after creation.
* Currency format for on-chain: Always use the exact name returned by `/BinanceOnchainWithdrawCoins` in the Currency field — including the network suffix, e.g. USDT (BEP20).
* Deposit flow: After calling `/binancepaydeposit`, redirect the client to the url field or display the qrLink. The client must complete payment in the Binance app.