Abstract: A telecommunications system and method is disclosed for allowing a calling mobile subscriber to activate a call back on busy feature and specify the maximum waiting period after which the call back is no longer attempted. Upon reception of a busy indication at an original Mobile Switching Center/Visitor Location Register (MSC/VLR) serving the calling mobile subscriber, the original MSC/VLR plays an announcement to the calling subscriber to collect the time interval beyond which the network should cease to attempt the call back. Thereafter, the original MSC/VLR sends a message containing the time interval to the end office or destination MSC/VLR associated with the previously busy called subscriber. In response, the end office or destination MSC/VLR Initializes a timer with the time interval, and, if the previously busy called subscriber becomes idle before the expiration of the timer, recalls the calling mobile subscriber.