The Differences

• An unlisted telephone number is not listed in the white pages of a local or regional telephone book. It remains available, however, to anyone who calls directory assistance. An non-published or unpublished telephone number is also not listed in the white pages of the local telephone book, nor is it available to those who seek it via directory assistance.
  
  

Unlisted Pros & Cons

• A directory unlisted telephone number is also unlisted in internal documents that telephone companies routinely sell to telemarketers and other business that broker information, adding a level of privacy that may be desirable. Cons include a monthly fee your telephone company will charge you for this service.
  
  

Nonpublished Pros & Cons

• An unpublished telephone number remains available on internal telephone company documents that can be sold to other businesses. Depending upon the specific company, an unpublished number may be less expensive than an unlisted one as it can still make money for the telephone company.
  
  

Considerations

• The charges that telephone companies add to your bill for the unlisted or unpublished services has come under attack by both consumer advocates and privacy advocates. Whenever any type of telephone service is initiated, listed or not, the customer specifies the names associated with the number. Legal names aren't required. Thus, one option to retain privacy and avoid a monthly charge is to use a name recognizable to friends and family only, such as a pet's name or that of a favorite character.