To block unwanted calls, a person can use anonymous call rejection or regular call rejection or add the phone number to the do-not-call registry. Other methods include having either a semi-private or private number listing.
Anonymous call rejection automatically blocks calls from both anonymous numbers and private numbers, while regular call rejection blocks calls from specific numbers chosen by the user. A semi-private listing is not in the telephone book but is available through directory assistance. Neither telephone books nor directory assistance provide private listings. To block telemarketers, the do-not-call registry allows users to input their numbers in a list managed by the Federal Trade Commission and forbidden to any type of solicitor.