United Payment Interface (UPI) is a mode of payment that you can use to make immediate transfers at any time! You can find more details about this here.
There are a few payment service providers (PSP) authorised by the National Payment Corporation of India (NPCI). You can set up your UPI and add a registered bank account. The UPI app will set up your Virtual Payment Address (VPA).
For e.g in BHIM, your default VPA will be <mobile number>@upi. If your mobile number is 123456789, then your VPA will be 123456789@upi.
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