What is a UPI PIN? Updated April 17, 2018 00:13 Follow UPI PIN (UPI Personal Identification Number) is a 4 or 6 digit secret code used to authenticate UPI transactions. Related articles Do I need to be a customer of a particular bank to use Truecaller? Is it compulsory to set UPI PIN during registration? 10 Cool Truecaller Tricks You Should Try! Watch Video Here! Are there any charges for transactions done via UPI? How do I change my UPI PIN? Comments 0 comments Please sign in to leave a comment.