It used to be that everyone had a landline phone in their home and searching for a number or address simply required opening the phone book and finding the name. This has become more complex now that cell phones are in common use and many people do not even have home phones, and if they do their number may be unlisted.

Even with the development of caller ID on most home phones, some numbers may show up without an identifying name and there are ways for callers to prevent their name from coming up. Reverse phone lookup providers have stepped up to these changing demands to provide a very useful service to modern phone users.

There are two common functions for these directories.

Locating Names

If you are receiving calls from someone and only a number is revealed on your ID, or you want to figure out cellular phone callers, reverse phone lookup directories can help you find out the name registered to the phone number in question. Just by entering the phone number you will be able to identify whoever is initiating those phone calls in question.

People in search of this service include those wanting to identify a number constantly phoning their spouse or children's cell phone, since there is no accessible directory for cell phone numbers. Other people may use lookup directories when they need to identify a name registered to a landline that may be unlisted. If you have a phone number but are uncertain who it is connected to, a reverse phone lookup service can help.

Finding Addresses

The other common use is to locate an address for someone, whether you know the name of the person or not. Once you find the contact information connected with a specific number most directories will deliver additional data as well, which includes the address of an home phone or the address listed to a cell phone number.

This may not be a typical need for most people, but it does have its benefits in some situations. For instance, consider a parent needing to find a teenager who has run away or is still out long after curfew. If they can come up with numbers from the teenager's belongings or cell phone a lookup directory could quickly tell them addresses and names of locations the teenager may be located.

More common situations may be looking for addresses to mail out party invitations to your child's friends. If you have their phone number you can access their address and easily deliver the invite without calling and tracking down other busy people.

Lookup directories can also deliver access to other various types of information, including income brackets or previous addresses, and one site even gives a map with an rough pinpoint of where the home or business is located.

There will be a nominal price for any legitimate reverse phone lookup directory, but if your business or personal situation requires accurate information it is worth the money in the end. The charge is required because this kind of information is not simple or free to research, collect, and protect, so issuing it on demand to people such as you must also come with a charge to cover such operational costs.

There probably will never be a phone book for cellular numbers, and even if they were compiled most likely a lot of the numbers would be unlisted just like many landline numbers right now. The only way to gain access to these numbers is to give a minor charge either to do a single number lookup or to join a lookup service if you will need to access the service long term.