> For the complete documentation index, see [llms.txt](https://docs.faspay.co.id/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.faspay.co.id/merchant-integration/api-reference-1/faspay-billing-api/callback.md).

# Callback

This API Callback service functions to process when the merchant transaction has been paid for by the customer. Merchant prepares a URL which later from Faspay will send data to that URL.

Method : POST

Format : JSON

### **Callback Parameter**

The following is the parameters that will be given by the Faspay system to the merchant system

{% tabs %}
{% tab title="Request Parameter" %}

<table><thead><tr><th width="200">Parameter</th><th width="144">Data Type</th><th width="283">Description</th></tr></thead><tbody><tr><td>billing_id</td><td>Numeric</td><td>Billing number generated by Faspay</td></tr><tr><td>service_id</td><td>Numeric</td><td>Unique code registered on the Faspay Billing service</td></tr><tr><td>transaction_number</td><td>Numeric</td><td>Merchant invoice number</td></tr><tr><td>billing_total</td><td>Numeric</td><td>Billing total</td></tr><tr><td>signature</td><td>Alphanumeric</td><td><p>Merchant's signature </p><p>SHA1(MD5(username+ password+transaction_number))</p></td></tr><tr><td>billing_status</td><td>Alphanumeric</td><td>Billing status (UNPAID, PAID, EXPIRED, CANCELLED)</td></tr><tr><td>payment_id</td><td>Numeric</td><td>Payment ID generated by Faspay</td></tr><tr><td>payment_amount</td><td>Numeric</td><td>Payment amount</td></tr><tr><td>payment_method</td><td>Alphanumeric</td><td>The channel name used for payment</td></tr><tr><td>payment_date</td><td>Datetime (YYYY-MM-DD hh:mm:ss)</td><td>The date when the bill was paid</td></tr></tbody></table>
{% endtab %}

{% tab title="Sample Request" %}

```json
{
  "billing_id": 1057,
  "service_id": 6,
  "transaction_number": "1233989228221148",
  "billing_total": "10000",
  "signature": "f4ebe62839b2d446ed13b3ca28f819a9ac0baa0a",
  "billing_status": "PAID",
  "payment_id": "1606804843001326",
  "payment_amount": "10000",
  "payment_method": "PERMATA VA",
  "payment_date": "2020-12-01 13:22:11"
}
```

{% endtab %}
{% endtabs %}


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