BIN (Bank identification number)
BIN stands for Bank Identification Number (4–6 digit number) which is used to identify the issuing bank. The BIN is used by payment schemes (VISA, Master Cards, Amex, etc.) to identify banks that are handing out cards using the payment scheme's label. An example would be if the user’s bank is the ING and they received a VISA credit card from that bank. In this case the first 4–6 digits of that credit card number represent the BIN.
The above example shows how the payment scheme (in this case VISA) is managing several BINs. Whenever VISA receives a request form an acquiring bank it has to know which bank the user is having their bank account with to properly reroute the request for verification.
The BIN has in total 16 digits. Out of those 16 digits, the first 4–6 are reserved for the bin. Therefore a BIN range for an issuing bank can look as follows:
123456 0000 000 000
123456 9999 999 999
The BIN above is 123456 and all remaining numbers can be used to generate the CC number.
On top of that, the payment scheme also hands out an acquiring BIN to the acquiring bank simply to know that the request received is coming from an acquiring bank. So all together this means that issuing banks receive a BIN and so do acquiring banks.
