Challan Identification Number is referred to as CIN. It is a 17-digit number made up of a 3-digit bank code and a 14-digit CPIN. When a payment is actually received by one of these authorised banks or the Reserve Bank of India (RBI) and credited to the appropriate government account that institution holds, a CIN is generated. It's a sign that the money has actually been received and credited to the right government account. The authorised bank notifies GSTN and the taxpayer of the CIN.