Area Code Lookup Guide
The absolute quickest (and cheapest) way to check an area code for any telephone number is to use this tool:
Find Area Codes
The boys over at fonefinder.net take the raw data from the national area code and phone number repositories and provide a very slick online lookup interface to lookup an area code from any phone number, or by any city. And the best part of course is that it’s FREE!
If you have a bit of time on your hands and always wanted to know how area codes are determined and assigned in the U.S., then browse on over to the North American Numbering Plan Administration. Information on current and future area code assignments, splits, and additions can be found there. For Canadian area codes, check this site.
If you need to trace a toll-free number to get the area code of the landline phone number assigned to it, start by calling 800-337-4194. This is Ameritech’s RespOrg (Responsible Organization) hotline that spits out the carrier name for any 800/888/866/900 number in the country!