Abstract: To simplify the configuration for achieving payment with a high degree of freedom in or near a shop, position information acquisition means of a payment system acquires shop terminal position information for indicating a position of a shop terminal and customer terminal position information for indicating a position of a portable customer terminal on which a customer performs a payment operation. Determination means determines, when the payment operation is performed on the customer terminal, whether a distance between the position of the shop terminal indicated by the shop terminal position information and the position of the customer terminal indicated by the customer terminal position information is smaller than a threshold value. Pay lent processing execution means is executable for payment processing based on a result of determination made by the determination means.