Image:Area code 202.svg, 350px, The red area is the District of Columbia
Washington, D.C., formally the District of Columbia and commonly known as Washington or D.C., is the capital city and Federal district of the United States, federal district of the United States. The city is on the Potomac River, across from ...
, served by area codes 202 and 771.
poly 0 50 49 54 103 84 111 88 101 107 118 130 143 139 179 140 211 188 238 203 260 240 259 248 248 250 255 262 253 357 1 357 Area codes 571 and 703
poly 1 1 0 45 52 48 117 84 109 109 121 127 180 136 199 164 254 112 345 204 264 286 258 358 420 358 420 1 Area codes 301, 240, and 227
desc bottom-left
Area
Area is the measure of a region's size on a surface. The area of a plane region or ''plane area'' refers to the area of a shape or planar lamina, while '' surface area'' refers to the area of an open surface or the boundary of a three-di ...
codes 202 and 771 are telephone
area code
A telephone numbering plan is a type of numbering scheme used in telecommunication to assign telephone numbers to subscriber telephones or other telephony endpoints. Telephone numbers are the addresses of participants in a telephone network, rea ...
s in the
North American Numbering Plan
The North American Numbering Plan (NANP) is an integrated telephone numbering plan for twenty-five regions in twenty countries, primarily in North America and the Caribbean. This group is historically known as World Zone 1, World Numbering Zone ...
(NANP) for
Washington, D.C.
Area code 202 was one of the
original North American area codes established in October 1947 by the
American Telephone and Telegraph Company (AT&T). After the State of New Jersey with
area code 201, the District of Columbia was the second numbering plan area (NPA). Area code 771 was added to the numbering plan area in April 2021 in creation of an
overlay complex to mitigate impending telephone number shortages.
History
Since the creation of the first nationwide
telephone numbering plan in 1947, most of the inner ring of the Washington metropolitan area has been a single local calling area, the Washington Metropolitan Exchange Area (WMEA). This is despite the fact that the WMEA was split between three numbering plan areas (NPAs): the District's 202,
301 in southern
Maryland
Maryland ( ) is a U.S. state, state in the Mid-Atlantic (United States), Mid-Atlantic region of the United States. It borders the states of Virginia to its south, West Virginia to its west, Pennsylvania to its north, and Delaware to its east ...
, and
703 in
Northern Virginia
Virginia, officially the Commonwealth of Virginia, is a U.S. state, state in the Southeastern United States, Southeastern and Mid-Atlantic (United States), Mid-Atlantic regions of the United States between the East Coast of the United States ...
. From the 1950s to 1990, it was possible to complete local calls in the WMEA with only
seven digits. The entire WMEA was reachable via long-distance services by dialing area code 202, for which purpose AT&T Long Lines had established cross-referenced operator routing codes for all affected central offices. This scheme was implemented via a system of
central office code protection, in which central offices in the three numbering plan areas could not duplicate any central office prefixes for any of the three area codes in the WMEA. For example, if the 202-574 exchange was in use in the District, the corresponding 703-574 or 301-574 exchange could only be assigned a safe distance from the metropolitan area, such as southwestern Virginia or the
Eastern Shore of Maryland
The Eastern Shore of Maryland is a part of the U.S. state of Maryland that lies mostly on the east side of the Chesapeake Bay. Nine counties are normally included in the region. The Eastern Shore is part of the larger Delmarva Peninsula that Ma ...
.
By spring 1990,
C&P Telephone (later part of Bell Atlantic and now
Verizon), the Regional Bell Operating Company for the District, advised the
North American Numbering Plan Administration (NANPA) that the last
interchangeable central office code in the area would be assigned in the second half of the year. The only remaining prefixes could not be assigned without eliminating seven-digit dialing in the region, leading C&P to terminate the central office code protection arrangement to make additional prefixes available for use. This change was implemented in a permissive dialing period from April 1, 1990, to October 1, 1990, at which time all home-NPA (HNPA) local calls maintained seven-digit dialing; all HNPA direct-dialed toll calls, required ''1'' and ten digits; foreign-NPA (FNPA) local calls were dialed with just the ten-digit number; FNPA direct dialed calls required dialing ''1'' and ten digits. Operator-assisted calls were all dialed as ''0'' and ten digits.
The end of central office code protection was intended to allow number blocks to be assigned in the Washington area that could not previously be assigned under the previous system. However, it did not provide enough relief to meet demand on either side of the
Potomac River
The Potomac River () is in the Mid-Atlantic (United States), Mid-Atlantic region of the United States and flows from the Potomac Highlands in West Virginia to Chesapeake Bay in Maryland. It is long,U.S. Geological Survey. National Hydrography D ...
. By the end of 1990, the Chesapeake and Potomac Telephone Company of Maryland determined that 301 was approaching exhaustion even with the end of central office code protection. It filed to assign
area code 410 to most of Maryland from the
Baltimore
Baltimore is the most populous city in the U.S. state of Maryland. With a population of 585,708 at the 2020 census and estimated at 568,271 in 2024, it is the 30th-most populous U.S. city. The Baltimore metropolitan area is the 20th-large ...
area eastward, effective October 5, 1991. In Virginia, the delay amounted to six years, until 1996, when
area code 540 was installed for the western portion of the old 703 territory; permissive dialing ended January 27, 1996.
The region's continued growth in the 1990s ultimately led to both suburban area codes being overlaid, with area code 240 overlaying 301 in 1997, and area code 571 overlaying 703 in 2000.
With 202 facing exhaustion in late 2022, the
North American Numbering Plan Administrator announced in October 2020 the addition of area code 771 to the District of Columbia. The Public Service Commission approved a plan to phase in the new area code over a 13-month period.
[ The installation of a second area code required transition to ten-digit dialing for all calls within the District. The overlay implementation commenced with a permissive dialing period from April 10, 2021, to October 9, 2021, during which ten-digit dialing of 202-telephone numbers was optional.] The first central office code assignments for 771 took place on November 8, 2021, for central office code 777, and on November 9 for 888.
Local calling
Even with the implementation of ten-digit dialing in the Washington metro, much of the Washington area is still a single local calling area. The District is the center of one of the largest toll-free calling zones in the eastern United States, covering large portions of Virginia and Maryland.
Areas such as Alexandria
Alexandria ( ; ) is the List of cities and towns in Egypt#Largest cities, second largest city in Egypt and the List of coastal settlements of the Mediterranean Sea, largest city on the Mediterranean coast. It lies at the western edge of the Nile ...
, Arlington, Fairfax, Falls Church, McLean and Tysons in Virginia ( 703/571) and Rockville, Gaithersburg
Gaithersburg ( ) is a city in Montgomery County, Maryland, United States. At the time of the 2020 United States census, Gaithersburg had a population of 69,657, making it the third-largest incorporated city and the ninth-most populous communit ...
, Upper Marlboro, Bethesda and Landover in MarylandLocal calling guide: Washington Zone 4, MD
/ref> ( 301/240) are a local call to Washington.
See also
* Area code 710
*List of North American Numbering Plan area codes
The North American Numbering Plan (NANP) divides the territories of its members into geographic numbering plan areas (NPAs). Each NPA is identified by one or more numbering plan area codes (''NPA codes'', or ''area code
A telephone numbering plan ...
References
External links
{{coord, 38, 54, N, 77, 2, W, display=title
202
Telecommunications-related introductions in 1947
202
Washington, D.C.