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

# Send Payment

> Start sending instant Bitcoin payments through the ZBD API.

## Description

This endpoint sends a payment on the Bitcoin Lightning Network. This is one of the main APIs which allow you to pay any [Charge](/payments/glossary#charge) in the network.

<Tip>The words *Charge*, *Payment Request*, and *Invoice* can be seen as equivalent in the context of requesting funds in the Bitcoin Lightning Network.</Tip>

## Usage

All payments in the Lightning Network are asynchronous. Though possible, most payments will not settle immediately on the API invocation. They do however tend to settle *immediately thereafter*, which means you **MUST** to provide the `callbackUrl` to receive updates about your app's payments.

<Note>If the Charge does not have a predefined amount (e.g. an `amountless invoice`), you can pass an `amount` property with a defined value to this API call.</Note>

## Configuration

### Header Parameters

<ParamField required header="apikey" type="string">
  ZBD Project API Key
</ParamField>

<ParamField initialValue="application/json" header="Content-Type" type="string">
  Content Type
</ParamField>

### Body

<ParamField required body="invoice" type="string">
  Lightning Network Payment Request / Charge
</ParamField>

<ParamField initialValue="‎" body="description" type="string">
  Note or comment for this Payment
</ParamField>

<ParamField initialValue="‎" body="amount" type="string">
  Amount to be paid to this Charge/Invoice -> in millisatoshis *(only valid if Amountless Invoice)*
</ParamField>

<ParamField initialValue="‎" body="internalId" type="string">
  Open metadata string property
</ParamField>

<ParamField initialValue="‎" body="callbackUrl" type="string">
  The endpoint ZBD will POST Payment updates to
</ParamField>

<ResponseExample>
  ```json Response theme={null}
  {
      "success": true,
      "message": "Payment done.",
      "data": {
          "id": "caafd318-527c-466b-81f2-441d3a092aae",
          "fee": "2000",
          "unit": "msats",
          "amount": "101000",
          "invoice": "lnbc1010n1p3mt8akpp5uyxhllflux2fvl36wjxh80wtqzdh2vjmu8cdyzuap578az80v74qdqcd3hzucmpwd5zqurp09kk2mn5cqzpgxqzjhsp550s770zy4puj76wqnua0hmym883gr07dhuast5ygcm44grl6z7ns9qyyssqgf7sumdmxwzgkq2m0h9lcv530sqs0m4t4shlu98djrrckrtulcmr8rear70dyftdm67jvgncxgz4jmd6ksx87jvnj88e39un48ssk4gp8vs4u5",
          "preimage": "8a14f6da89d4a8ffd09677f585b7c377de72744b7c3713d3c115fa71ca4fc290",
          "internalId": "11af01d092444a317cb33faa6b8304b8",
          "status": "completed"
          "processedAt": "2023-01-04T15:48:29.805Z",
          "confirmedAt": "2023-01-04T15:48:29.805Z",
          "description": "Custom Payment Description",
      }
  }
  ```
</ResponseExample>