CALL-WAITING PHONE SERVICE WITH MESSAGE TRANSMISSION FUNCTION DURING BUSY STATE

PURPOSE:To send a voice message to a 3rd party telephone set by displaying an incoming telephone number to a display device of a telephone set when an incoming connection comes to a telephone set of a call-waiting phone service subscriber during busy state from a 3rd party telephone set. CONSTITUTION:When an incoming connection comes from a 3rd party telephone set 3 to a telephone set 1 of a call-waiting phone service subscriber during busy state, an incoming telephone number is displayed on a display device 12 of the telephone set 1 and a voice message is sent to the telephone set 3 of the 3rd party by the depression of a message button 13. Thus, when the call-waiting phone service subscriber cannot be switched to the 3rd party telephone set on its way due to a reason of important content of talking or the like, who is the 3rd party is to be confirmed and the busy state is informed to the 3rd party by sending a message. Thus, the call-waiting phone service is improved.