A system and method of discounting a price-per-unit (PPU) of fuel during a fueling transaction by a customer at a fuel merchant. In one aspect, the invention identifies an issuer of the customer's credit card, associates the issuer with a PPU discount for the fuel, and discounts the posted PPU by an amount equal to the PPU discount associated with the identified credit card issuer. In another aspect, the invention determines that the customer participates in a reward program with a vendor with whom the fuel merchant has a relationship agreement for providing PPU discounts for fuel in exchange for redeemed reward points from the reward program. The customer's reward points are converted to a PPU discount, and the posted PPU of the fuel is discounted accordingly.