As of October 2012:
In addition, in Canada:
* The tiny town of Hyder, Alaska, is in area code 250, but calls there are billed as calls to British Columbia, Canada.
There are several U.S. states that still have only one area code for the entire state:
207 = Maine
208 = Idaho
302 = Delaware
307 = Wyoming
401 = Rhode Island
406 = Montana
603 = New Hampshire
605 = South Dakota
701 = North Dakota
802 = Vermont
808 = Hawaii
907 = Alaska
In Canada,
204 = Manitoba*
306 = Saskatchewan*
506 = New Brunswick
709 = Newfoundland & Labrador
902 = Nova Scotia AND Prince Edward Island
867 = Yukon AND Northwest Territories AND Nunavut
* Manitoba and Saskatchewan will be adding overlay area codes in 2012 and 2013, respectively.
Two
No. The entire 713 area code is an overlay with 832, which also overlays the 281 area code.
Albuquerque is in area code 505.
There are too many too list here, and most states have more than one area code, but many websites provide this information. See link.
No, there are others, such as Maine.
The same local telephone number can exist in many different area codes. (After all, that's the whole point of area codes.) If you know where the telephone number is from, and if that place has only one area code, you can find out that way.
No, Cricket Wireless offers service in several area codes.
One can find information about the area code 813 at the White Pages website or at the Area Code website. The area code has been in use since 1953 and serves the Tampa area.
North American area code 829 is one of the three area codes for the Dominican Republic. Calls from the United States to area codes 809, 829, and 849 will incur international call charges.
Springfield, IL utilizes one area code which is area code 217.
In general, yes, but not always. Cellphones in the United States use the same geographic area codes as landline numbers. A person may have a cellphone in a different area code from their home because they moved and kept the cellphone number from their previous home town, or because they requested a number in a neighboring area code (e.g., live in one area code but work in an adjacent area code).
If you have only the 7-digit number for a cell phone number in an area with more than one area code, there is no way to determine which area code it belongs to, other than guessing. In particular, in the United States and Canada (except for numbers in area code 600), cell phones use the same geographic area codes as landline phones, and in all cities and even most rural areas, you can take your telephone number with you, even switching from cellular to landline or vice-versa.
In the United States, telephone area codes do not cross state lines. However, within a state, there are many cases where a telephone area code boundary divides a city or town between two or more area codes. The only states left that have only one area code each are Alaska, Hawaii, Idaho, Montana, Wyoming, North Dakota, South Dakota, Delaware, Rhode Island, Vermont, New Hampshire, and Maine. In addition, the entire state of West Virginia is an overlay; although there are two area codes, there is no boundary between them, since they both serve the entire state. The first area code overlay in the United States was area code 917 for New York City. In the original plan, 917 was to be the area code for mobile phones and pagers, with mobile users in the 212 and 718 area codes (then the only two area codes for New York City) forced to move their numbers to 917. However, federal regulators held that it was illegal to discriminate on the basis of class of service (i.e., landline versus cellphone, etc.) in deciding who got the desirable 212 and 718 numbers and who got the less-desirable 917 numbers. The next overlays in the United States were in Maryland in 1997. However, since 2007, there have been no area code splits, only overlays. Canada has had only overlays since 1999. Thus, there are more and more parts of the North American Numbering Plan (the area code system that serves the USA, Canada, and 18 assorted island nations and territories, mostly in the Caribbean) that have two or more area codes for the same location.