| Have you ever really looked at your credit | | | | The check digit is a number that is |
| card and tried to figure out what that huge | | | | calculated by applying a special formula to |
| string of numbers really means? Do these card | | | | all of the other numbers. The check digit is |
| issuers have so many customers that your | | | | the result of that formula and is used as an |
| account number has to be 16 digits long? | | | | anti-fraud check. |
| | | | |
| You may be surprised to know that all those | | | | To keep things from getting too confusing, |
| numbers you see actually do stand for | | | | look at your card as you follow along for the |
| something, and it's not just who you are. | | | | next steps. |
| Let's take a look. | | | | |
| | | | American Express |
| Most of the major credit card companies | | | | |
| operate on the same system when choosing a | | | | The American Express Card uses digits three |
| credit card number. Other cards like gas | | | | and four for type (business or personal) and |
| cards, department store cards and phone cards | | | | the currency of the cardholder's country of |
| go their own way. Let's concentrate on the | | | | origin. The next digits from the fifth |
| ones that all play by the same rules. | | | | through the eleventh are account numbers. |
| | | | |
| The very first digit in the series will be a | | | | Digits twelve through fourteen indicate the |
| 3,4,5, 0r 6. This number designates the type | | | | card number within the account and the last |
| of card as follows: | | | | digit is the check digit. |
| | | | |
| 3 = a Travel & Entertainment Card like | | | | Visa |
| American Express or Diners Club. | | | | |
| | | | With Visa, digits two through six represent |
| 4 = Visa and Visa-branded debit cards, cash | | | | the bank number. Beginning with the seventh |
| cards, etc. | | | | digit and running through the twelfth or the |
| | | | fifteenth represents the account number and |
| 5 = MasterCard and MasterCard-branded debit | | | | the last number is the check digit. |
| cards, cash cards, etc. | | | | |
| | | | Since all Visa cards do not have the same |
| 6 = Discover | | | | amount of numbers in the sequence, the number |
| | | | of digits in a group may vary. |
| American Express and Diners Club use the | | | | |
| second digit to identify the company. That | | | | MasterCard |
| means that Diners Club cards will start with | | | | |
| either "36" or "38", and American Express | | | | For MasterCard, the second digit, through to |
| cards will use either "34" or "37". | | | | anywhere between the third and the sixth |
| | | | digit is the bank number. All remaining |
| The remaining numbers in the series are used | | | | digits, except the check digit at the end of |
| for different purposes depending upon the | | | | the series, identifies that cardholder's |
| card type and issuer. | | | | account. |
| | | | |
| In most cases, the next group after the | | | | Now that we've gone over it all, you're |
| opening series of numbers represents the | | | | probably wondering why you were ever |
| routing number of the card-issuing bank, the | | | | wondering in the first place. Just remember |
| group after that is the user's account | | | | though, knowledge is power. Some things are |
| number, and the final digit is a check digit. | | | | just fun to know. |