Credit Card Account Number: Simply Explained

What does creditย card account number mean?

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A number that is unique and that identifies a credit card account. Each credit card that is issued around the world will have a unique number, and no two banks will ever issue a card with the same number. The account number is personal to the owner and this information is necessary when making online purchases where the cardholder is not present.

The credit card account number will be made up of a certain amount of digits which will be displayed on the front of the card with a security number on the rear face of the card. Although the vast majority of credit cards are now pin enabled to avoid other people using stolen cards, it is vital that you keep your details private and report your card stolen or missing if you lose it.

Though most people arenโ€™t aware of it, the numbers on a credit card arenโ€™t just random. There is a definite order and the numbers give very specific information about the card and the issuer.

The very first number of every credit card is an industry identifier that tells which industry issued the credit card.

Cards beginning with a 1 or 2 are issued by the airline industry. If they are travel and entertainment cards (like American Express and Diners Club) theyโ€™ll begin with a 3. All Visa credit cards start with a 4 and all Mastercards begin with a 5. The number 6 is used for Discover credit cards.

Once the industry is determined the card number goes on to identify the issuing bank. The next six numbers of the card identify which bank issued the card and is responsible for payments.

After the first seven numbers comes your own personal account number, which is comprised of all the remaining numbers, except the final number.

That final number is known as the checksum and it is set using the Luhn formula, which was patented by IBM scientist Hans Peter Luhn in 1960. The Luhn formula uses all the other numbers on your card to verify that it is a valid card number.

This formula and the checksum digit are primarily used to protect against input errors such as entering the wrong card number during the checkout process on an ecommerce site. If the digits you enter are off by even one, the checksum digit will be able to determine that the numbers you entered donโ€™t add up properly based on the Luhn formula, and youโ€™ll be informed you entered an invalid number.

So, now you know that thereโ€™s far more than you probably expected included in those digits on a credit card.

Rebekah Carter

Rebekah Carter is an experienced content creator, news reporter, and blogger specializing in marketing, business development, and technology. Her expertise covers everything from artificial intelligence to email marketing software and extended reality devices. When sheโ€™s not writing, Rebekah spends most of her time reading, exploring the great outdoors, and gaming.

Comments 3 Responses

  1. David Simpson says:

    I can’t find my chase credit card not do I know the credit card info numbers

  2. Stephen wisher says:

    I received two new cards with different numbers, but when I activated them I was given the same info for each card. It was the same as the old card. Is that normal?

    1. Bogdan Rancea says:

      I think yes, as long as they are linked to the same bank account.