Abstract: An automatic busy message sending system for use in telephone communication to inform the calling subscriber, when the called subscriber's line is busy, of the duration of the busy status by voice. As the calling subscriber can receive, when the called subscriber's line is busy, a busy status message corresponding to the duration of the called subscriber's busy status instead of a busy tone, the calling subscriber can more accurately anticipate the ending time of the called subscriber's communication, and thereby minimize the repetition of the call initiating procedure. This service can be realized without having to add extra equipment to the electronic switching system currently in operation.