Have you ever wondered about the sequence of numbers shown on your credit card, like how those numbers were chosen or what they mean? Most of us identify our issuing credit card company by the logo on the card. However, a little known fact is each credit card issuer has a specific sequence of numbers that appears on every one of the credit cards they issue and is not to be used by their competitors.
This means the numbers that appear on your credit card are not randomly selected. They actually are a series of numbers that set up some internal structure for the issuing organization.
The first 6 digits called the Issuer Identification Number (IIN) on almost all major credit cards determines the credit card network that the card belongs in. That means by reviewing those first few numbers on your card, you can tell if your card is a MasterCard, Visa, American Express or even a Discover card.
List of Issuer Identification Numbers
Those who follow this system of order are participating in the IIN system. The following is a list of issuer identification numbers by major credit card company:
- American Express: 34, 37
- Discover Card: 6011, 60112-60114, 601174, 601177-601179, 601186-601199, 622126-622925, 644-649, 65
- MasterCard: 51-55
- Visa: 4
That small piece of plastic you use to make paying for your expenses easier is just a fragment of the Goliath credit card system. When you are granted credit from a lender, they trust you to pay back the money. The credit card they issue is the key to accesses your line of credit from the credit card issuer in a convenient manner. The electronic systems by which your charges are verified rely on the smallest component–the numerical sequence–to organize not only your transaction, but the transactions of all cardholders worldwide properly.