Custom Checkout

Paytm Custom Checkout is an ideal checkout solution for the entrepreneurs and big enterprises, who want to collect payments through a customized checkout page on their website / mobile app..

Using this solution, you can design your checkout form and appearance complimenting your brand theme and business needs. Regardless of the payment source, you can customize the checkout interface on a granular level. It allows you to accept payments through a host of payment sources - Paytm wallet and postpaid, Debit/Credit Cards, Net Banking, EMI and UPI on your website/app. Paytm complies with PCI regulations for secure handling of over 200 millions of saved cards of Paytm users while processing a transaction.


Custom checkout solution supports the following features:

  • Single integration flow for both website and mobile application
  • Lets you present your preferred payment sources on the checkout page, including the saved cards and linked UPI bank accounts of the user’s Paytm account
  • Seamless and frictionless payment experience
  • Supports auto-read bank OTP functionality on the app version
  • Allows you to save new payment cards in local vault corresponding to your MID

Demo of Custom Checkout

Overview of payment flow via Custom Checkout

  1. User visits your website/mobile app and adds goods/services into the shopping/order cart.
  2. User proceeds to checkout and then your backend server calls the Initiate Transaction API. Paytm returns the Transaction Token in response.
  3. Your backend server calls the Fetch Payment Options API using the Transaction token to receive the available payment options like Wallet, CC/DC, NB, UPI, EMI etc. and the user's saved instruments.

    Note: You may call the Fetch Payment Options API before Initiate Transaction API. Please get in touch with us to get more details.

  4. You render the fetched payment instruments and sources on the checkout page of your web or app.
  5. User selects a payment source and then based on the payment instrument selected by a user, you call the respective API.
  6. Once the user clicks the Pay button to complete the payment, you call the Process Transaction API using the transaction token received above. Paytm PG processes the transactions and sends the response.
  7. You call the Transaction Status API through your backend server to verify the transaction response.
  8. You notify the payment status to the user and proceed with the order/service fulfilment.

You can refer Postman Collection to understand the custom checkout integration flow.

Postman Collection - Custom Checkout

The postman collection for Custom Checkout solution lets you quickly understand the flow integration. Click the button below to download and import the APIs collection in the postman. This would also help you test the APIs on the integration environment.

Run in Postman

To set up the environment for using the Postman Collection, click here.


Before you begin the integration, make sure you follow the steps below:

  1. Create an account on Paytm as a merchant. Click how to create an account.

    Note: Save the MID and merchant key generated in the above step.
  2. Go through the checksum logic to understand how to generate and validate the checksum.

Integration Steps

This section explains how you can integrate the custom checkout flow on your website/mobile app platform. The integration flow varies as per the payment sources configured for your MID.

  1. User adds the product in a cart and proceeds to checkout on your website/app. You create order and your backend server calls the Initiate Transaction API to generate the transaction token (txnToken).
  2. You can either display the payment methods on your own or you can use the Fetch Payment Options API to fetch and display the available payment methods to the user.
  3. Click the links below to get the details about integration steps for each payment source:
    1. Paytm Wallet and Postpaid integration
    2. Credit/Debit Cards integration
    3. Netbanking integration
    4. EMI integration
    5. UPI integration