Phone directory publishers provide copies of the yellow pages for free because they make money by selling advertisements in the commercial directory. Phone companies lose money publishing the white pages, but most states require companies that offer land line service to offer a free residential directory.
Because ad rates and revenues are based on circulation, directory publishers make the most money by circulating their books to as many households as possible. These companies earned 66 percent of their 2014 revenue on advertisements in printed directories in 2014, so it would be bad business to decrease circulation by charging for the yellow pages. Despite increased use of the Internet to find phone numbers, many areas still receive multiple paper phone books every year.