A UTR (Unique Transaction Reference) number identifies one bank transfer. The RBI describes the RTGS UTR as a 22-character code, and its NEFT FAQ asks you to give your bank the UTR when you need a transfer traced.
Where to find it
In the transfer's line on your statement, or in the transaction details in your bank's app or net banking. If someone says they have paid you, ask them for the UTR: it lets your bank find the credit.
UPI and IMPS references
UPI and IMPS transfers carry their own reference number. On the statements Fynora has read it is 12 digits.
Example lines
Made-up lines in the usual shape. Your bank's wording will differ.
NEFT CR-UTIB0XXXXXX-EXAMPLE PAYER-100000000001The reference at the end of the line is what you quote to trace it.
Questions
How do I trace a transfer with a UTR?
Give your bank the UTR along with the date, the amount, the sender's IFSC, and the receiver's name and IFSC. The RBI's NEFT FAQ lists these as the details that speed up tracking.