Instant Payment Notification (IPN) enables you to automate various aspects of your business by sending transaction details to your server whenever a payment is received or a transaction status changes. When used with credit card or Express Checkout transactions, IPN is not intended for obtaining real-time payment status; rather, it is designed to provide asynchronous notifications, such as when an eCheck clears or a chargeback occurs.
When a customer makes a payment, the payment gateway sends a notification to your server at a URL you specify. This notification includes all relevant payment details (e.g., customer name, amount), as well as an encrypted code. The variables included in the notification are listed in the IPN Variable Reference. Please note that these variables may vary depending on the payment gateway.