Abstract: A credit card processing system involving the use of a machine for reading the data encoded in the magnetic stripe of such a card and for printing such data in MICR characters, at the point of sale, along the bottom of the merchant's bank sales slip copy of each transaction under the credit card. The machine also has means for selecting any one of four punches for making a punch out in said bank copy in any one of four predetermined optional ABA standards positions to designate the transaction as a credit or charge transaction and whether it is to be processed by EDP or EFT procedures. The system also includes all of the various instrumentalities necessary to process each transaction, guided by the punch out information, through the merchant's bank, the clearing house, and the issuer institution for final posting and billing.