Back
UPI Plugin for E-commerce SDKs
Why UPI Integration Matters for E-commerce
UPI has become the dominant payment method for digital commerce in India, accounting for a significant share of online transactions across consumer categories. For e-commerce businesses, integrating UPI payment capability directly into their checkout flow is no longer optional but a foundational requirement for conversion optimisation. A smooth, native UPI checkout experience reduces drop-offs caused by redirection to third-party payment pages and builds consumer trust. Developers building e-commerce applications, subscription platforms, or marketplace products need to understand the available integration patterns, the role of Payment Service Providers, and the compliance requirements that govern UPI-based merchant payments.
How UPI Plugin Integration Works at a High Level
A UPI plugin for e-commerce does not connect directly to the UPI infrastructure. Instead, the merchant's application integrates with a Payment Service Provider's SDK or API, which in turn communicates with the PSP's UPI switch and the underlying banking network. When a customer selects UPI at checkout, the plugin initiates either an intent flow or a collect flow depending on the integration type and device context. The PSP handles authentication, routing, and settlement, while the merchant's backend receives a callback confirming payment success or failure. The plugin essentially acts as a bridge between the merchant's application and the PSP's payment gateway layer.
Intent Flow Integration for Mobile Applications
The intent flow is the preferred integration method for mobile e-commerce applications on Android and iOS. In this flow, the merchant's app constructs a UPI deep link or intent containing the merchant's VPA, the transaction amount, a unique order reference, and other required parameters. When the customer proceeds to pay, the device displays a list of installed UPI applications from which the customer selects their preferred app. The selected app opens with the transaction details pre-filled, and the customer authenticates using their UPI PIN. The merchant's backend receives a real-time callback from the PSP confirming the outcome. Intent flow provides a seamless in-app experience and is recommended for native mobile applications.
Collect Flow Integration for Web Platforms
For browser-based e-commerce platforms where intent deep links cannot trigger installed UPI apps, the collect flow is the standard approach. In this flow, the customer enters their UPI ID at checkout, and the merchant's backend instructs the PSP to send a collect request to that VPA. The customer receives a payment request notification in their UPI application, opens it, verifies the merchant and amount, and authenticates with their UPI PIN. The transaction result is communicated to the merchant via a server-to-server callback. While the collect flow introduces a slight additional step compared to intent, it is widely used for desktop e-commerce and remains effective for categories where customers are comfortable sharing their UPI ID.
Technical Requirements for UPI SDK Integration
Integrating a UPI payment plugin requires the merchant to complete onboarding with a PSP or payment gateway provider that holds the necessary authorisation from the National Payments Corporation of India. This involves submitting business documentation, completing KYC verification, and receiving production credentials including a merchant ID and API keys. On the technical side, the integration typically involves importing the PSP's SDK into the application, implementing the payment initiation and callback handling logic, and configuring webhook endpoints for real-time payment status updates. Developers should also implement idempotency mechanisms to handle network failures gracefully and ensure that duplicate payment requests do not result in double charges.
Security and Compliance Considerations
All UPI integrations must comply with the security standards prescribed by the National Payments Corporation of India and the Reserve Bank of India. Merchant applications are prohibited from storing the customer's UPI PIN or any sensitive authentication credentials. Transaction data must be transmitted over encrypted channels, and API keys must be stored securely on the server side and never exposed in client-side code. Merchants are also required to display accurate transaction amounts and merchant names at the checkout stage so that the customer sees correct information in their UPI application before authentication. Deviation from these requirements can result in PSP suspension of the merchant's integration.
Testing and Going Live
PSPs typically provide a sandbox environment where developers can simulate UPI transactions using test VPAs and mock bank responses. Thorough testing should cover successful payment flows, payment failures, timeout scenarios, and duplicate transaction handling. Once testing is complete, the merchant must submit the integration for review and certification by the PSP before access to the production environment is granted. Post-launch, monitoring dashboards provided by the PSP allow merchants to track transaction success rates, identify failure patterns, and optimise checkout performance. Regular SDK updates from the PSP should be applied promptly to ensure continued compliance with evolving NPCI technical specifications.
UPI transactions are governed by NPCI guidelines. Stashfin is an RBI-registered NBFC. Please ensure transaction details are correct before confirming payment.
