A communication system capable of conducting efficient multi prepaid service and also improving the quality and convenience of prepaid communication service. Service request transmitting section transmits a service request for a prepaid service, and prepaid service executing section executes the prepaid service. Registration information transmitting section transmits registration information for executing the prepaid service. User request receiving section receives the service request and the registration information. Based on the service request and the registration information, prepayment control section performs prepayment control including a process of allotting the balance of prepayment to a plurality of prepaid services to be conducted simultaneously. Prepaid service providing section provides the prepaid service in accordance with the corresponding allotment of the balance.