Residential phone numbers that are unlisted can at times be hard to track down, but with some basic knowledge and information, you can find an unlisted residential phone number at no cost. Keep in mind, however, that the person's number is likely unlisted for a reason. If you know the person well, or have good reason to contact them, go ahead and find the number. But if you have no business contacting the person on the phone, consider another method of communication, as the person likely does not want an unsolicited call.
Gather as much detailed information as possible about the person with the unlisted residential number. It is easier to find an unlisted number when you know the person's name, address, age, former residence or schools attended. Use search engines or social network sites to find further information. Those sites might even list the person's unlisted residential phone number.
Use the Internet. Technology allows us to find and access information online, even if the information is not publicly listed. Visit an online white pages phone book, which may list the number, even if the physical phone book does not. You can find the number usually with the person's name and city of residence, although the more details you have, the easier it is to narrow down the search. Most sites provide this service for free, but certain search engines do require a fee.
Ask a mutual family member or friend, or a common acquaintance of the person you are trying to call. If the mutual friend is not comfortable giving you the person's number, ask for an e-mail address so you can e-mail the person and ask for his number, or ask the mutual friend to have the person call you instead.
Hire an unlisted phone number service if you cannot track down the number. In desperate situations, paying for a premium service can help you find the number quickly and easily. See the Resources section for links.