Extended-length payment account issuer identification numbers

A method comprising:

• receiving payment credentials in a POS (point of sale) terminal from a payment-enabled mobile device;
• inserting the payment credentials into a transaction authorization request, the payment credentials including a PAN-length identifier that identifies an issuer of the selected payment account, the payment credentials further including a payment token that is separate from the PAN-length identifier;
• and
• transmitting the transaction authorization request from the POS terminal to a transaction acquirer.

A method comprising:

• receiving, in a computer, a transaction authorization request message, the transaction authorization request message containing first data in a payment account number field, the first data for identifying an issuer of a payment account, the transaction authorization request message including a second data field, different from the payment account number field, the second data field containing second data different from the first data, the first data in a format for a payment account number and including at least 14 digits;
• processing, by the computer, all of the at least 14 digits of the first data to identify the issuer of the payment account;
• processing, by the computer, the second data to provide an account indicator that indicates the payment account;
• inserting, by the computer, the provided account indicator in the payment account number field of the transaction authorization request message in place of the first data;
• and
• transmitting, by the computer, to the identified issuer of the payment account, the transaction authorization request message with the account indicator inserted therein.