What is the USSD code * 99?

*99# is a USSD (Unstructured Supplementary Service Data) based mobile banking service from the National Payments Corporation of India (NPCI). It allows users to access financial services, such as checking bank balance, transferring money, and setting UPI PIN, by dialing the code from their mobile number registered with the bank. This service works on all GSM phones without requiring internet access or a smartphone, promoting financial inclusion.