Reviewed by Jan 05, 2021| Updated on
The Issuer Identification Number (IIN) points to the first six to eight digits of a credit, debit, or any other type of payment card number issued by a financial institution.
IIN is unique to the issuer and its partnering network provider. The IIN identifies the processing network used for the card's transactions. It is used to validate the card's authenticity and status. The main purpose of IIN is to identify the card network and not the cardholder.
Every time a card is swiped to pay for a transaction, a card processor does a series of verification processes to ensure the cardholder is authorized to make the transaction. It also makes sure that the account has sufficient funds. Payment card numbers vary in length based on the issuing institution; they may comprise of as many as 19 digits.