BIN (Bank Identification Number)

A BIN (Bank Identification Number) is the first six to eight digits of a card number. It identifies the bank that issued the card, the network it runs on, and the type of card. It is also called an IIN (Issuer Identification Number). The remaining digits identify the individual account.

What a BIN tells you

• The issuer, which is the bank that approves charges on the card.
• The card network, such as Visa, Mastercard, Amex, or Discover.
• The card type, such as debit or credit, consumer or commercial, and standard or premium.
• The country where the card was issued.

These details affect cost and risk. A US commercial card has different interchange than a consumer debit card. A card issued in one country used by a buyer who claims another can raise a fraud flag.

The move to 8 digits

Card networks moved from 6-digit to 8-digit BINs because the 6-digit ranges were running out. Systems that read only the first six digits can misclassify newer cards.

Why it matters

Processors use BIN data to route and price payments and to spot fraud before authorization. Fraudsters use it too. In card testing attacks, they generate numbers within a known BIN range and try them at a checkout. A card saved with tokenization still exposes details that come from the BIN, such as brand, card type, and country, without exposing the full number.