Abstract: Systems and methods are presented for blocking nuisance calls to communications devices, in which incoming calls are selectively blocked if the caller has made a threshold number of attempts to call a communications unit within a specified interval of time. The nuisance call blocking service may be selectively performed only for communications customers subscribing to the service, and the service may include the ability to designate a list of allowed callers who can make unlimited call attempts, with non-designated calling parties being limited to the threshold number of call attempts within the specified time period before being blocked.