Provided is a payment system capable of making recurring payment processing through only single processing at a predetermined period and thereby enhancing credit card transactions on rents of real-estate rental properties. For this purpose, rent information sent from a CAT 14 to a host computer 12 is stored in a recurring payment database 36, and a sales telegram of the rent stored in the recurring payment database 36 is sent to payment request determination means 20 on the assumption that the payment is within a guarantee period stored in a guarantee period database 38.