Issuer Identification Number – Definition

Cite this article as:"Issuer Identification Number – Definition," in The Business Professor, updated April 16, 2020, last accessed October 25, 2020,


Issuer Identification Number (IIN)

The issuer identification number (IIN) is a six-digit code used to identify a credit card issuing institution in international exchange. The IIN is unique to each issuer as no two credit card issuing institutions can have the same IIN. The IIN is the first six to eight digits you will find on a credit card or even debit card, this number identifies the card issuer.

A Little More on What is an Issuer Identification Numbers (IINs)

Usually, the issuer identification number (IIN) is the first six to eight noticeable digits on a credit or debit card. The International Organization of Standardization assigns IIN to identify credit card issuers in the international exchange environment. IIN was formerly six digits, but the increase in the number of payment card issuing companies led to an increase in IIN from six to eight.

Payment cards such as debit or credit cards have varying card numbers but usually, 19 digits, part of the 19 digits is a unique code created by the issuing company to track the transactions of cardholders. The issuer identification number does not identify the credit card holders, only the issuing companies, but each time a user performs transactions with the credit card, verification is done to ensure that the cardholder is authorized to make the transaction.

Common Issuer Identification Numbers

Each credit card issuing institution has a unique identification number for easy identification in the international interchange environment. The IIN is peculiar to each issuer, this means two companies cannot have the same IIN. The IIN is the first six to eight digits of a payment card, for instance, MasterCard has 2221 to 2720, 51 to 55 as IIN, while the Discover Card has 6011, 622126 to 622925, 624000 to 626999, 628200 to 628899, 64, 65.

IINs Versus Payment Card Numbers

Payment Card Numbers are identification digits found on a customer’s payment card, often linked to the customer’s account. Every payment card has its card number and it varies from company to company and holder to holder. The IIN is part of the payment card number, it is the first six to eight digits out of the 19 digits that are found on a payment card.

While IIN represents the unique identification code of a credit card company, the payment card number identifies the cardholder and also links the customer to the issuing company. (Hence, the payment card number identifies the issuing company as well as the cardholder as linked to the customer’s account. Payment card numbers help issuing companies keep a record of the transactions performed by a cardholder and also gives authorization for such transactions.

References for “Issuer Identification Number (IIN) › Personal Finance › Loans

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