What is a primary account number?

The primary account number is a 14, 15, 16, or 19-digit number on credit cards, debit cards, and other types of payment cards. It’s also called a payment card number and serves as a unique identifier.

How primary account numbers work

Primary account numbers serve specific purposes.

The first six or eight digits in a PAN are the issuer identification number (IIN), also called bank identification numbers (BINS). The first digit in the IIN is the major industry identifier (MII) and identifies the industry associated with the card. For example, numbers 1 and 2 are for the airline industry.

Different card processing networks use different industry identifier numbers. For Instance, Mastercards start with a 2 or a 5, Visa cards with a 4
The last five or seven digits in the IIN or BIN show the bank or financial institution that issued the card.
The next set of numbers in the PAN are unique to the cardholder. The last number in the PAN is called the “check digit” or “check sum” number. It makes sure the card number is accurate and hasn’t been typed in incorrectly.

Primary account numbers vs. account numbers

In some cases, the primary account number is also the cardholder’s account number at their financial institution. In other instances, the numbers are different.

Primary account numbers vs. secondary account numbers

Credit and other card issuers usually allow primary account holders to add another account holder or authorized user to their card account. The second person can get a card with their name on it but with a different primary account number. Some issuers will use the same primary account number for the primary account holder and the second person, but the primary account holder must pay charges or withdrawals on the card.

Business credit card accounts operate differently. The primary account number for corporate credit cards gives each employee a card with a separate account number. This allows companies to identify and track charges for each employee’s card.

What do the other numbers on a credit card mean?

Beyond the primary account number, credit and debit cards usually have a three- or four-digit number printed on the front or back, known as the CVV, or “card verification value.” The CVV number protects against unauthorized use in online transactions. A thief who has a credit card number, but not a physical card, might not be able to submit the CVV to complete the transaction.