The first four digits are the issuings bank identifier. If you are elite, you can get a list of active banks and their 4 digit prefix. I mean very elite like a big CC clearinghouse merchant. So don't ask for a list here you won't find it. The next two sets of digits are accounts, the last 3 digits of the last set (in 16 digit accounts) are account number, the last digit is a checksum of the rest of the digits, similar to the way your checking account # last digit is a checksum, however checking account # checksums can be omitted, you cannot omit the last digit on a credit card. bill wrote: ------------------------------- What do the first four numbers of a credit card mean?
The first 4 digits are the issuing bank, though this can be a little confusing, since some banks are subsidiaries of other banks, etc. etc. Further, the FIRST DIGIT tells you something. If 4 is the first digit then it's a VISA. If 5 is the first digit, then it's a MASTERCARD. If 6 is the first, then it's a DISCOVER or OTHER credit issuer.
