Less than $2,500 More than $2,500
Always Never Sometimes

How long is a credit card number?

Want to know how long a credit card number is? Well, read on because you will learn the answer to that question and much more than you maybe ever wanted to know about credit cards and the credit card numbering system.

Credit cards have advanced significantly since their inception in the 1920′s. Originally fabricated as metal, fibrous, or paper tokens, credit cards have since evolved into plastic cards specifically sized to ISO (International Organization for Standardization) specifications.

ISO/IEC 7810:2003 defines bank cards to follow format ID-1, which is 85.60 x 53.98 millimeters. ISO/EIC 7812 further regulates the numbering scheme that is found on all credit cards, which became regulated by the United States Congress during the 1970′s.

Credit Card Numbers Demystified

While the actual length of a credit card number varies by the credit card company it must follow a specific identification protocol as outlined by ISO. American Express cards are 15 digits long, Diners Club ranges from 14 to 16 digits based on the type of card, Discover Card has 16 digits, MasterCard has 16 digits, and Visa is 13 to 16 digits long. The maximum length of any card is 19 digits.

The very first digit of every credit card is the Major Industry Identifier (MII), which is predetermined by the industry. 0 is for securities, 1 and 2 are for airlines, 3 is for travel and entertainment as well as banking and finance, 4 and 5 are for banking and finance, 6 is merchandising and bank and finance, 7 is for petroleum, 8 is for healthcare and telecommunications, and 9 is reserved for national standard entities. Any industry requiring the 9 industry code must then followed by a three digit country code.

The MII digit is also part of the six-digit Issuer Identification Number (IIN). The American Bankers Association is responsible for maintaining these codes and, while they are supposed to be confidential, the popularity of credit cards such as MasterCard and Visa make the numbers somewhat common knowledge. The intention of keeping the IIN undisclosed is for added security to protect against fraud, but many other tools have since been implemented to aid in this endeavor.

Following the MII is the Individual Account Identifier, which can vary in length from seven to twelve digits. This number makes up the remaining numbers on the card with the exception of the last digit. Account numbers are randomly assigned and while they do not need to be lengthy for practical purposes, they were designed this way for security purposes. The longer that the number is, the less chance that there will be for erroneous entry and incorrect charges. Depending on the length of the credit card number, the chances of keying in an incorrect number can be 1 in 100,000 or even 1 in a trillion.

Another security measure that checks the validity of the credit card number is the Validity Check Code, or the Checksum, which is the very last single digit on your credit card. By using an algorithm (called the Luhn Algorithm) created by an IBM scientist named Hans Luhn, the last digit of the credit card is able to verify if the credit card number is correct.

Controlled Payment Numbers

Controlled Payment Numbers are disposable credit card numbers that can be used to prevent online credit card fraud. Many credit card companies are now offering this service, such as Bank of America’s Shop Safe, Citibank’s Virtual Account Numbers, and Discover Card’s Secure Online Account Numbers. They are programmed for a one time use and usually have a quick expiration date. Depending on the system used by the credit card company, the Controlled Payment Numbers are usually set up by the cardholder to be limited to a certain purchase price, a set dollar limit, or restricted to a specific merchant.

The idea behind a Controlled Payment Number is to provide a cardholder with a single use credit card number that can be used for making an online purchase. A lot of credit card fraud occurs over the internet, whether indirectly through stealing your information from an unsecured server or directly from someone working for the merchant who obtained your credit card information when you made your purchase.

By using a Controlled Payment Number, a cardholder can make a credit card purchase online without having to reveal his real credit card number. The purchase will be billed to his account just like any other transaction, but anybody who attempts to use the number a second time will be declined.

Other Security Measures To Protect Against Fraud

While a Controlled Payment Number keeps your credit card number secure from online theft, the use of a PIN can help reduce fraudulent use of your card at the Point of Sale (on location, such as at a retail store). Some cards can also be set up with territory limitations, preventing the chance of international fraud.

Most credit card companies also have alert systems in place that will notify you immediately of any suspected fraud and typically offer free protection against any fraudulent charges that are placed on your credit card. Once fraud is reported, you typically complete an affidavit of fraudulent charges and the credit card company will then remove the suspicious charges and conduct an investigation on your behalf.

With all of the security measures in place, credit cards are often considered to be much safer to carry than cash, for those who use them responsibly. They allow for spontaneous purchases, such as last minute trips to the grocery store, and provide you with a way of shopping on line or by telephone without having to give out your bank account information.

Now that you know practically all that there is to know about credit card numbers (and then some) you can compare and shop for credit cards now in three easy steps using the free credit card “Chaser” tool on our home page. Try it out for free today!

Similar Articles:

Credit Cards

Disclaimer: This content is not provided or commissioned by American Express, Visa, MasterCard, Discover, or any other credit card company or issuer. The opinions expressed here are the author's alone, not those of any credit card company or issuer, and have not been reviewed, approved or otherwise endorsed by any credit card company or issuer. Credit Card Chaser may be compensated through various affiliate programs with advertisers. As always, Credit Card Chaser is an independent website commmitted to helping people research credit card offers and find the best credit card!

Less than $2,500 More than $2,500
Always Never Sometimes