Area code 878 is an overlay area code in Southwestern

Pennsylvania Pennsylvania (; (Pennsylvania Dutch: )), officially the Commonwealth of Pennsylvania, is a state spanning the Mid-Atlantic, Northeastern, Appalachian, and Great Lakes regions of the United States. It borders Delaware to its southeast, Ma ...

, centered in

Pittsburgh Pittsburgh ( ) is a city in the Commonwealth (U.S. state), Commonwealth of Pennsylvania, United States, and the county seat of Allegheny County, Pennsylvania, Allegheny County. It is the most populous city in both Allegheny County and Wester ...

. It simultaneously overlays the region's two existing area codes, 412 and 724, making

ten-digit dialing Ten-digit dialing is a telephone dialing procedure in the countries and territories that are members of the North American Numbering Plan (NANP). It is the practice of including the area code of a telephone number when dialing to initiate a telep ...

mandatory in the Pittsburgh area. 412 had served southwestern Pennsylvania for 41 years before 724 was created for most of the old 412 territory outside of Pittsburgh in 1998. Bell Atlantic (now part of

Verizon Verizon Communications Inc., commonly known as Verizon, is an American multinational telecommunications conglomerate and a corporate component of the Dow Jones Industrial Average. The company is headquartered at 1095 Avenue of the Americas in ...

), the main telephone provider in the area, wanted to implement 724 as an overlay to spare residents and businesses the burden of changing their numbers. However, overlays were still a new concept at the time, and met with considerable resistance due to the need for ten-digit dialing. Thus, the proposal was changed to a geographic split. Within two years, however, both 412 and 724 were on the verge of exhaustion. Overlays had gained more acceptance by then, so 878 was implemented as an overlay. It came into effect on August 17, 2001. Although ten-digit dialing has been mandatory in southwestern Pennsylvania since 2001, no 878 numbers were assigned for more than a decade due to number-conservation procedures implemented in both Pittsburgh itself and the suburbs. On February 15, 2013, the Pennsylvania Public Utility Commission announced it would start to issue 878 numbers in the 724 territory sometime within the next year, as 724 was nearly exhausted. The first 878 numbers were assigned in April 2013, nearly 12 years after the overlay was activated. On September 15, 2015, the first

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(999) was assigned into the 412 territory. As of February 2020,

is issuing 878 telephone numbers inside 412's original territory.

References

See also