UPI: India’s Digital Payments Backbone
- Unified Payments Interface (UPI) enables instant bank-to-bank payments by connecting users, banks and payment apps through infrastructure operated by the National Payments Corporation of India (NPCI).
- In July 2026, UPI processed 2,366 crore transactions, averaging around 7,600 transactions/second, worth nearly ₹30 lakh crore.
- In FY 2025–26, UPI processed 24,160 crore transactions worth ₹314 lakh crore, accounting for 85% of India’s digital payment transactions by volume.
- According to the International Monetary Fund (IMF), UPI accounted for 49% of global real-time payments by volume in 2025.
How a UPI Transaction Works
- 1. Initiation: The payer enters the recipient’s UPI ID (e.g., shankar@flutebank), which acts as an alias linked to the recipient’s bank account.
- 2. Routing: The payment app sends the request to the UPI system operated by NPCI, which provides the switching and routing infrastructure connecting around 730 participating banks.
- 3. Authentication: The payer confirms the transaction using the UPI PIN, establishing authorisation.
- 4. Bank Verification: The payer’s bank verifies the account, available balance, transaction authenticity, transaction limits and potential fraud indicators.
- 5. Transaction Routing: After approval, NPCI routes the transaction to the recipient’s bank and linked account.
- 6. Debit & Credit: The payer’s bank debits the amount, while the recipient’s bank credits the amount.
- 7. Confirmation: The recipient’s bank reports the credit to NPCI, which relays the status back through the payer’s bank and UPI app.
What Happens Behind the Screen?
- UPI relies on TPAPs (Third-Party Application Providers) such as payment apps and PSPs (Payment Service Providers) that connect apps/banks with NPCI infrastructure.
- Banks exchange multiple messages to initiate, authenticate, authorise, debit, credit and confirm each transaction and its status.
- The infrastructure includes servers, databases, APIs, network switches and routers, monitoring and security systems, redundant systems, cooling and power infrastructure.
- Software components include APIs, transaction switches/routers, databases, message queues, encryption, authentication, fraud detection, reconciliation and disaster-recovery systems.
- These layers ensure interoperability, transaction integrity, predictable failure handling and trust among participating banks.
UPI ID: How It Identifies the Account
- A UPI ID is an alias, not the bank account number, and is created/maintained by the user’s bank according to its rules.
- The part before “@” identifies the user/account alias, while the part after “@” identifies the bank/service that can resolve that alias.
- Banks can distinguish identical names using numbers, while some users can customise their UPI IDs.
- One bank account can have multiple UPI IDs/aliases, which can also be embedded in QR codes.
Evolution of UPI
- NPCI developed UPI with Nandan Nilekani as an advisor and RBI providing regulatory guidance.
- UPI was built as an interoperable layer over Immediate Payment Service (IMPS), enabling round-the-clock interbank fund transfers.
- April 2016: RBI Governor Raghuram Rajan piloted UPI with 21 banks; bank-app access followed within months.
- UPI 2.0 (2018): Added overdraft-account linking, mandates, invoice verification, signed QR codes and enhanced autopayments.
- UPI crossed 100 crore transactions/month in October 2019.
UPI’s Internationalisation
- NPCI International Payments Limited (NIPL), a wholly owned NPCI subsidiary, promotes international adoption and interoperability of India’s digital-payment systems.
- Bhutan (2021): First foreign adoption, through cooperation between NIPL and the Royal Monetary Authority of Bhutan.
- Subsequently adopted in Singapore (2021), UAE (2022), France, Mauritius, Sri Lanka and Nepal (2024), Qatar (2025), and Cambodia, Greece and Maldives (2026).
- NIPL is reportedly working towards interoperability with payment systems of Indonesia, Malaysia and Thailand.
