OPINION | Redesigning UPI infrastructure for the digital economy's next phase

The growth of UPI has been far from linear.

India’s Unified Payments Interface (UPI) has swiftly evolved from a peer-to-peer payments tool into the backbone of the country’s digital economy. As of 2025, it processes over 19 billion transactions monthly and serves more than 400 million users. However, this exponential growth is revealing cracks in the infrastructure supporting it. Most first-generation UPI switches are struggling to keep pace with increasing transaction complexity, new use cases like embedded credit, and growing regulatory demands. The banks are under pressure to modernize their switching architecture to ensure scalability, durability, and long-term competitiveness in the digital era.

UPI’s Exponential Growth is Reshaping Infrastructure Demands

The growth of UPI has been far from linear. What began as a peer-to-peer payments tool has evolved into a high-throughput digital rail powering a broad spectrum of financial services including high-volume merchant transactions across online and offline channels, transaction-linked credit, rising traffic from Third-Party Application Providers (TPAPs), and even RUPAY credit card-linked payments.

Simultaneously, regulatory mandates from the RBI and NPCI now demand real-time reconciliation, fraud detection, and efficient dispute resolution, significantly raising the bar for infrastructure capabilities. These expanding use cases introduce complex architectural demands related to scalability, security, availability, and compliance. Yet, most legacy UPI switches are designed for a much simpler environment, and flexibility needed to support this scale and complexity, creating risks to system performance, regulatory alignment, and continued innovation.

Paths for Modernization: Sidecar vs. Full Replacement

Faced with the limitations of legacy systems, banks are rethinking their UPI switch strategy, with two dominant models emerging. The first is the sidecar switch, where a modern UPI infrastructure runs alongside the core system. This approach allows banks to isolate and optimize specific workloads like merchant payments or TPAP traffic without disrupting core operations. Benefits include faster go-to-market for new UPI capabilities, improved load management, traffic segmentation, and greater regulatory agility. It offers a low-risk, cost-effective way to scale and innovate without overhauling existing infrastructure.

The second model is full replacement, ideal for banks dealing with outdated systems or heavy technical debt. This greenfield approach enables them to build a future-ready architecture from scratch, with built-in scalability, compliance, and extensibility. Advantages include native integration with tools for observability, automation, and regulatory support, along with readiness for evolving ecosystems like Credit on UPI, ONDC, and IOT payments. Though resource-intensive, full-stack modernization offers deeper control, resilience, and the agility needed to thrive in an increasingly digital and interoperable financial scene.

Why Can’t the Infrastructure Shift Wait for Banks?

The urgency to modernize UPI infrastructure goes beyond just technological upgrades, it is driven by four critical, ecosystem-wide forces. First, with UPI processing more than 19 billion transactions monthly as of July 2025, even minor outages or latency can have far-reaching effects across the entire financial system, particularly during high-demand periods like festival seasons or high demand promotions and schemes. Second, regulatory expectations from the Reserve Bank of India (RBI) and the National Payments Corporation of India (NPCI) are becoming more stringent, demanding mandatory dispute resolution timelines and robust operational risk controls. These requirements must now be embedded into the core switch architecture, resulting in enhanced load on legacy systems. Third, emerging services like contextual lending, micro-credit, and embedded finance necessitate seamless integration with marketplaces and digital service providers, something that legacy infrastructure struggles to support. Lastly, in the fast-paced world of real-time digital commerce, even milliseconds of transaction delay can lead to failed payments, abandoned shopping carts, and significant reputational damage, underlining the critical need for infrastructure that can handle such demands without compromising on performance or reliability.

What Next Generation UPI Switch Must Deliver

To stay ahead in UPI value proposition, banks must follow six core design principles that define a future-ready performance-driven architecture. First, it must be API-first and event-driven to enable rapid, seamless integration with partners and platforms. Second, use-case segmentation is essential for isolating transaction types like merchant payments or TPAP flows, improving performance and compliance. Third, real-time observability allows for continuous monitoring and faster issue resolution, minimizing downtime. Fourth, native compliance support must be embedded at the architectural level, with built-in capabilities like ODR, fraud detection, and audit trails. Fifth, elastic scalability is crucial for handling traffic spikes without compromising reliability. Finally, smart transaction routing, dynamically directing traffic based on network load, cost, or user experience, will be a key differentiator.

Ultimately, in today’s environment, UPI infrastructure is no longer just operational but a strategic growth lever for banks. Banks that modernize their UPI switches now are setting the foundation to lead the next phase of digital financial innovation.

(Deepak Chand Thakur, CEO & Co Founder, NPST.)

Views are personal, and do not represent the stand of this publication.