US Area Code Answers
- Information about US-based area codes and prefixes. Find the city, carrier, location, and more information about any phone number with this free service.
- http://www.areacodeanswers.com

US Area Code Locations
- Provides a list of towns and cities covered by each US area code including overlays and splits.
- http://www.areacodelocations.info

AT&T US Area Codes
- List of US area codes for each state, with a list of important cities and towns in each of the telephone area codes. Provides good information on overlays and splits.
- http://www.consumer.att.com/global/english/usa_codes.html

Time Dial
- Displays the current time, international dialing code, area codes and currency converter for almost anywhere. Includes instructions on country codes and international dialing code parts usage.
- http://www.TimeDial.net

How to Call Abroad From US and Canada
- Calling guide for United States and Canadian residents listing international country and city codes, phone books and time zones.
- http://www.howtocallabroad.com/

World Telephone Numbering Guide
- Lists and links to current international dialing codes and area codes with formatting guides and provides information on recent and historical changes.
- http://www.wtng.info/

Time and Date
- International dialing codes for almost any country and area codes for many cities. The interface includes a dropdown selector and local times are provided with dialing codes.
- http://www.timeanddate.com/worldclock/dialing.html

Dial Codes Plus
- Listing of international dialing codes and area codes with instructions.
- http://dialcodesplus.com/

Dial Code
- Find international dialing codes and area codes by specifying location. Information on direct dial prefixes. Flash user interface.
- http://www.dial-code.com

NPA NXX Source
- Databases for sale providing data on area codes and telephone exchange prefixes in the North American Numbering Plan.
- http://www.npanxxsource.com

World Search Dial Codes
- Contains world telephone codes and time zone information. Search by city, country or number.
- http://iptop.net/eng/code.html

UK Dial Me
- A directory of telephone STD dialing codes in the UK.
- http://www.dialme.co.uk

Verizon - US Area Code Lookup
- Find the major locations in a certain area code by entering the area code, or find the area codes that are used in a certain state by entering the state name.
- http://www22.verizon.com/areacodes/

US Switchboard - Area Code
- Find United States area code by city and state, Find City and State by area code.
- http://www.infospace.com/swbd.main/white-pages/reverse-lookup

UK Phone Information
- Returns area information, map, BT charge information, and nearby exchange names for telephone numbers, access/short codes, or the name of a location.
- http://www.ukphoneinfo.com/

US Area Code Finder
- Area code lookup for the United States with maps. Search by state or by code.
- http://www.areacodesearchengine.com

FAQs on Area Codes from FCC (USA)
- The Federal Communications Commission answers frequently asked questions regarding area codes in the US.
- http://www.fcc.gov/Bureaus/Common_Carrier/Factsheets/areacode.html

LincMad
- Information about North American area codes, featuring changes, historical data and area code map. Detailed information on overlays and splits.
- http://www.lincmad.com/

exUSSR Phone Codes
- Includes all cities of Russia, Ukraine, Belorussia, Moldova, Lithuania, Latvia, Estonia, Kazakhstan, Georgia, Uzbekistan, Azerbaijan, Armenia, Kirgizia, and Tadjikistan.
- http://phonecodes.narod.ru/

International Dialing Codes
- International and national direct dialing prefixes and instructions.
- http://kropla.com/dialcode.htm

North American Numbering Plan Administration: Area Codes
- Find North American codes by a map, number, or location. Includes information on future planned area codes and a free downloadable area code database.
- http://www.nanpa.com/area_codes/index.html

CE - US Area Code Changes
- Lists of exchanges that have moved or are moving from one North American area code to another.
- http://frodo.bruderhof.com/areacode/