Abstract: A method comprises receiving a payment instruction including a payment system routing number and a unique code associated with a payee, and employing the routing number to determine whether it includes routing information for a specific financial institution. If so, then the payment instruction is transmitted based on the routing number. The transmitted payment instruction includes the unique code associated with the payee. If the routing number is determined to not include routing information for a specific financial institution, then account identification information of the payee and a first system routing number are retrieved based on the unique code, and the unique code included in the payment instruction is replaced with the retrieved account identification information, and the routing number is replaced with the retrieved first system routing number. The payment instruction with the account identification information is transmitted to the payee and/or a financial institution associated with the payee.