# Callbacks

Omypayments API is designed so that merchants receive notifications by having the system call their API whenever an invoice status changes. To use this functionality, set the Callback URL in your account settings. 

**Important:** The merchant’s endpoint must be publicly accessible and return a `200` HTTP status code upon receiving a callback.

**Callback Payload:**

```json
{
    "id": "UUID", // Invoice ID
    "usdAmount": "100.00", // Invoice amount in USD
    "status": "pending", // Invoice status
    "productTitle": "Test Product", // Product title
    "extraData": null, // Additional invoice information.
    "cryptoAmount": "0", // Amount in selected cryptocurrency (or null if not chosen)
    "crypto": { // Cryptocurrency data (or null if not chosen)
        "id": "uuid", // Crypto UUID
        "title": "Tether USD", // Crypto title
        "symbol": "USDT" // Crypto symbol
        "contractAddress": "0x0000000000000000000000000000000000000000", // Crypto contract address
        "decimals": 6, // Crypto decimals
        "logoURI": "https://..." // Crypto logo URI
    },
    "network": { // Network data (or null if not chosen)
        "id": "UUID", // Network UUID
        "chainId": "56", // Network chain ID
        "symbol": "BSC", // Network symbol
        "name": "BNB Chain", // Network title
        "networkType": "evm" // Network type
    },
    "address": "0x0000000000000000000000000000000000000000", // Payment address (or null if not chosen)
    "expiredAt": "2025-01-01 00:00:00", // Invoice expiration datetime (UTC+0)
    "transfer": { // Payment transaction details (or null if not available)
        "from": "0x0000000000000000000000000000000000000000", // Transfer from address
        "hash": "0x0000000000000000000000000000000000000000000000000000000000000000" // Transfer hash
    }
}
```


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