Disclosed is a method and an apparatus for providing an alternative telephony service which automatically switches an originating call between a basic telephony network and an alternative telephony network, and a method of inducing a caller or a receiver to subscribe to a service having a cheaper call rate by notifying the caller or the receiver of an inverse call charge which can be reduced according to whether telephony communication is performed using a basic telephony or an alternative telephony. Accordingly, it is possible to automatically connect the telephony communication using the basic telephony or the alternative telephony according to a telephony communication condition of the receiver, and thus reduce inconvenience due to a direct control of the receiver and first select a telephony communication scheme having a cheap call rate. Further, it is possible to more actively save a telephony communication call charge by naturally recommending the subscription and the use of the alternative telephony service through the notification of the inverse call charge to a non-subscriber or a non-user of the alternative telephony service.