The present invention is directed to a system for processing coupons by a self checkout system, where the self checkout system includes at least one self checkout station coupled to a server. In a first aspect, a self checkout system includes a server for managing the self checkout system and at least one self checkout station coupled to the server, where the self checkout station includes a scanner for scanning at least one item for purchase by a customer, a coupon reader for receiving a coupon from the customer, and a coupon manager. The coupon manager attempts to validate the coupon against the at least one item scanned by the customer, and if the coupon fails to validate, the coupon manager stores the coupon in a coupon pool at the server such that the stored coupon can be utilized at a subsequent sales transaction.