202 area code

Area code 202 is the North American telephone area code for Washington, D.C.. The area code was one of the original area codes established in October 1947 by AT&T in the North American Numbering Plan (NANP).

After the State of New Jersey with area code 201, the District of Columbia was the second Numbering Plan Area (NPA). NPAs that covered an entire administrative region received a code in which the second digit was '0'.

As of 2012, no plans exist to overlay the 202 area code, as NANPA estimates the current supply of numbers is sufficient at least to the year 2019. Washington is thus one of the largest cities where seven-digit dialing is still possible. However, calls are connected if the area code is dialed. There is no provision for long-distance calls within the area code.

From 1947 to 1990, area code 202 was an unpublished alternate area code for the nearby suburbs in Maryland and Virginia, which were officially in area codes 301 and 703, respectively. This was possible because the entire Washington metropolitan area is a single LATA. Every number on the Maryland and Virginia sides of the Washington metropolitan area was given a non-published alternate number in 202. This arrangement allowed local calls throughout the metropolitan area to be dialed using only seven digits. For example, a telephone number in Kensington, Maryland, that was officially 301-949-xxxx could be dialed as 202-949-xxxx. One side effect was that a prefix could only be duplicated in jurisdictions a safe distance from the metropolitan area, such as the Eastern Shore of Maryland or southwestern Virginia.

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