Bank Identification Number

A payment card number, or simply a card number, is the card identifier found on payment cards, such as credit cards and debit cards, as well as stored-value cards, gift cards and other similar cards. In some situations the card number is referred to as a bank card number. The card number is merely a card identifier and does not identify the account to which it is linked by the issuing company, nor does it identify the cardholder. The card number identifies the issuer of the card, which is then electronically associated by the issuing organization with one of its customers and then to the customer's designated bank accounts. In the case of stored-value type cards, there is no necessary association with a particular customer. Card numbers are allocated in accordance with ISO/IEC 7812. The card number is usually prominently embossed on the front of a payment card.

The payment card number differs from the Bank Identifier Code (BIC/ISO 9362, a normalized code—also known as Business Identifier Code, Bank International Code, and SWIFT code). It also differs from Universal Payment Identification Code, another identifier for a bank account in the United States.

The leading six digits of the card number is the "issuer identification number (IIN)", sometimes referred to as the "bank identification number (BIN)". The remaining numbers on the card are referred to as the primary account number or PAN. IINs and PANS have a certain level of internal structure and share a common numbering scheme set by ISO/IEC 7812. Payment card numbers can be up to 19 digits, as follows:

The first six digits of a card number (including the initial MII digit) are known as the issuer identification number (IIN). These identify the card issuing institution that issued the card to the card holder. The rest of the number is allocated by the card issuer. The card number's length is its number of digits. Many card issuers print the entire IIN and account number on their card.

In the United States, IINs are also used in NCPDP pharmacy claims to identify processors, and are printed on all pharmacy insurance cards. IINs are the primary routing mechanism for real-time claims.

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