India has become the world leader in fast payments due to UPI's rapid growth, processing more than 18 billion transactions monthly since its 2016 launch, according to an IMF fintech note. The Unified Payments Interface now dominates electronic retail payments while cash usage proxies decline.

The IMF study, titled 'Growing Retail Digital Payments: The Value of Interoperability', highlights how UPI's interoperable platform has become the world's largest retail fast payment system by volume. Digital payments have risen substantially relative to ATM withdrawals, indicating a persistent shift away from cash transactions.

The note emphasizes that interoperable systems like UPI foster digital payment adoption more effectively than closed-loop alternatives. However, IMF authors warn policymakers to monitor for dominant private providers and maintain competitive, open systems as the platform matures.