Methods are disclosed for reducing occurrences of nuisance calls. A called party identifies a call as an undesired (or "nuisance") call after answering, screening or reviewing recorded messages of calls. In one embodiment, the called party receives or screens a call and informs a terminating office that it desires to block future calls from the calling party. The terminating office determines the directory number of the calling party and causes the directory number to be added to a blocking database. In another embodiment, a called party reviews one or more prior messages recorded by a messaging system (e.g., answering machine or voicemail system) and flags a message (e.g., message #2) as originating from an undesired caller. The messaging system determines the directory number of the undesired caller and instructs a service provider to add the directory number to a blocking database. Thereafter, in either or both embodiments, the blocking database is consulted upon receiving an incoming call and, if the call is from a directory number in the blocking database, the call is ended or routed to an announcement without ringing the called party phone.