The Wireless Back Door
Cellular Secrets Prefix Finder Managing Numbers Keep Your Number Home
Wireless Phone Number Finder
Identify the telecom carrier that supplies service to a phone customer, and their location.  Enter the 6-digit Area Code and Prefix (NPA-NXX) of the phone number on these sites and find the carrier and location. A few areas have numbers assigned to different carriers based on the 7th digit. Some numbers no longer conform to these records after having been "ported" through Local Number Portability. Old company names are shown as that is how they are still listed in the administrator's records. 

Telco Data
A frequently-updated and easy-to-use site. Enter your Area Code and Prefix and get a result of the name and location of the wireless and wireline carrier that was originally assigned that Prefix.

Free Carrier Lookup
This site gives you the most accurate results for the carrier name, and adjusts for known Number Portability changes. You may not get location information.

The official Area Code & Prefix-assigning organization, the North American Numbering Plan Administration. Choose a state and you get all Prefixes for that state and Area Code, wireless and wireline. The results are large files.  Locations are shown in a code that you may or may not be able to figure out.

Local Calling Guide
A database that provides a cross-reference among switches and local calling areas which can be tailored with a small or great amount of detail. Use this site to find what exchanges are 'Local' to a particular cell phone number. It also refers back to the NANPA database.

Is It Local?
Find out if there is a long distance charge to call from one prefix to another. This applies mostly for wireline-to-wireless and wireline-to-wireline numbers. This is a great resource to find a wireless number that is local to your home phone.

Fone Finder
Enter the first 6 or 7 digits to get a result. The site includes Canadian and other international numbers.

Google Numbers
If you enter the full 10-digit phone number into a Google or other search, you may be surprised at the results. This is a fairly common way to track down suspicious callers who sound legitimate but aren't.  Be aware that your search results could return a number that belongs to a real person or business who did not call you, but the caller ID was fooled to make it appear that they did.

Manage Phone Numbers
If it's your own phone number that needs work, we have a whole page of ideas to manipulate your number to make it look like you want, ring where you want, keep it out of troublesome hands, and have it live with the right carrier.

▶ What is an NPA-NXX Number?
North American phone numbers are in the format (where N is any digit from 2 through 9, and X from 0-9):

(Example:  213-867-5309)
  • NPA identifies the 3-digit Area Code (Numbering Plan Area)

  • NXX identifies the Exchange or 'Prefix' (Central Office) within the NPA

  • XXXX identifies the individual subscriber number within the NXX