The Unified Payments Interface (UPI) is an instant, real-time payment system developed by National Payments Corporation of India (NPCI) facilitating inter-bank transactions. It is a unique solution that can be used to transfer money and make payments using the Immediate Payments Service (IMPS). UPI is an initiative by NPCI, regulated by RBI. UPI works 24/7. Federal Bank offers the UPI API stack for fintech and startup partners to readily integrate UPI services in their products .