Checkout Integration Guide

Released : 2026/01/01

Introduction

This guide provides a clear, end-to-end reference for integrating the Payment API. It covers authentication, payment flows, request parameters, payment processing, transaction handling, response interpretation, webhook notifications, and transaction status verification.

General Information

The Checkout service provides a secure payment experience that enables businesses to collect customer payment details and process transactions efficiently. All API requests must be submitted in JSON format.

To use the Checkout service on a website, an integration process is required. This integration offers a set of APIs that allow businesses to customize and control their payment processing workflows. These APIs support payment acquisition (sales) through defined interactions between the business website and the payment system and also the refund requests from the authorized businesses for their transactions.

Payment Flows

It supports two payment integration models: Hosted Checkout and Server-to-Server (S2S). Both options provide a secure payment flow while allowing businesses to choose the integration approach that best fits their technical and operational requirements.

Hosted Checkout

With Hosted Checkout, customers are redirected to a secure hosted payment page to complete their payment. The flow can include 3D Secure authentication when required by the issuing bank.

Hosted Checkout Payment Flow

1. 1. Customer enters payment details
   • Using the provided hosted payment page URL, the customer enters the required billing information, selects a payment method, and provides the necessary payment details.
2. 2. Payment Processing & Authorization
   • It processes the payment request and submits it for authorization through the applicable payment flow.
3. 3. 3D Secure Authentication
   • When required by the issuing bank, the customer completes the 3D Secure authentication step before the payment can proceed.
4. 4. Customer Redirection
   • After processing, the customer is redirected to the configured success or failure page based on the transaction outcome.
5. 5. Verify Transaction Status
   • The business should verify the final transaction status using the Status API, particularly when additional authentication or asynchronous processing is involved.

Server-to-Server (S2S)

With Server-to-Server (S2S) integration, the business collects payment details on its own platform and submits the transaction directly to the API. This approach provides greater control over the checkout experience and allows the business to build a customized payment interface.

Authentication - Generating an API Key

The API Credentials page displays the business in the credentials table, where the required integration credentials can be generated.

Payment Flow

A payment request is submitted directly to the API. Depending on the card, issuer, and authentication requirements, the transaction may complete immediately or may require additional customer verification.

2DS and 3DS Transactions

2DS transactions can complete immediately without an additional authentication redirect. 3DS transactions require the customer to be redirected to an authentication page to complete the required verification.

Callbacks

Transaction results are delivered asynchronously to the callback URL provided in the payment request. The statusUrl webhook allows the merchant system to receive the transaction result after processing, including the final result of a 3DS flow.

Environments

Sandbox and production environments are available. Use sandbox credentials for testing and validation.