India

UPI is the world's largest instant rail by volume and the standard to beat

17.5 billion UPI transactions in March 2026 is more than every other retail instant rail on the planet combined. The architectural choices — zero MDR on P2M below ₹2,000 for small merchants, open ecosystem with competing third-party applications (PhonePe, Google Pay, Paytm, bank apps), VPA-based addressing instead of account numbers — are being studied as a reference model by central banks from Brazil to Saudi Arabia to Pakistan. Cross-border UPI corridors with Singapore, UAE, Bhutan, Nepal, Sri Lanka, Mauritius and France are now operational.

The MDR question is the unresolved fault line

P2M UPI transactions below ₹2,000 for small merchants carry zero MDR by policy; RuPay-debit interchange was also set to zero. This has driven extraordinary adoption but left banks and PSPs funding the infrastructure via government subsidies (₹15bn FY25) and cross-subsidisation. Finance Ministry budgets now show subsidy compression; the industry-long debate about whether UPI MDR should return above a threshold is active again in 2026.

Credit-on-UPI is the next structural expansion

RBI enabled pre-sanctioned credit lines over UPI in September 2023; 'credit on UPI' now routes small-ticket consumer credit and working-capital limits through the same VPA interface as deposit accounts. Banks disbursed over ₹80bn via credit-on-UPI in FY25. The implications for card-based EMIs are material: unsecured digital credit is moving onto the UPI rail rather than onto a plastic one.

Credit-on-UPI turns every VPA-enabled Indian into an identifiable, Aadhaar-KYC-verified credit endpoint. Lenders integrating pre-sanctioned lines for MSMEs and gig-economy workers — with repayment sweeps via UPI AutoPay — have a first-mover advantage over card-EMI incumbents. The regulatory primitive exists; the UX work is still early.

Operational UPI corridors with Singapore (PayNow), UAE (Aani), France, Sri Lanka, Mauritius, Bhutan and Nepal turn the Indian diaspora-remittance book into an instant rail. Remittance operators rebuilt around corridor UPI see MTO-level fees compress to near-zero on sending-side customer acquisition; margin shifts to FX and integration.

Vendors building B2B embedded-finance products for Indian SMBs can now compose Account Aggregator (financial-data sharing), ONDC (commerce), UPI (payments) and Credit-on-UPI (financing) into a single integration surface. The infrastructure is state-provided and standards-governed; differentiation is at the UX and vertical-workflow layer.