Area code 878
Area code 878 is an overlay area code for area codes 412 and 724 in Southwestern Pennsylvania centered in Pittsburgh. It came into effect on August 17, 2001.
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), 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 due to the Pittsburgh area's rapid growth and the proliferation of cell phones and pagers. Overlays had gained more acceptance by then, so 878 was implemented as an overlay.
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 is nearly exhausted. At the moment, numbers from the 878 area code will not be assigned in Pittsburgh itself (the 412 area) until it runs out of numbers as well.
The first 878 numbers were assigned in April 2013, nearly 12 years after the overlay was activated.
Coordinates: 40°01′37″N 79°54′50″W / 40.027°N 79.914°W
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