About: Unlisted number

In telephony, an unlisted number (United States, New Zealand), ex-directory number (United Kingdom) silent number, silent line (Australia), or private number (New Zealand, and Canada) is a telephone number that, for a fee, is intentionally not listed in telephone books. Although an unpublished number is not included in the phone book, an unlisted number may be available from the phone company's information operator. When used for residential households they're primarily for privacy and security concerns. When it has personal value it is called a vanity number.