Area code 770 is a telephone area code in the North American Numbering Plan (NANP) serving all or part of 29 counties in North Georgia, including most of Atlanta's suburbs. It was split from area code 404 in December 1995, just three years after the creation of area code 706.
The creation of 706 was intended as a long-term solution to relieve exchanges in North Georgia. However, within a short time, 404 was close to exhaustion once again due to the proliferation of cell phones, fax machines, and pagers in the fast-growing Atlanta metro area. While it was apparent that the metro area could not stay entirely within 404, 770 was put into service sooner than anticipated as part of the fallout from the creation of 706. When 706 was originally created, it included several fast-growing exurbs of Atlanta. However, BellSouth put them back into 404 after residents complained about no longer being associated with the better-known area code. However, 404 had been close to exhaustion even before the creation of 706, and the restoration of the exurban areas forced the entire suburban ring of metro Atlanta to lose 404 sooner than originally planned.
Currently, 770 completely surrounds 404. The two area codes are split roughly by Interstate 285, known locally as the Perimeter. Generally, 770 includes most of the metro area outside the Perimeter, while 404 serves Atlanta itself and most suburbs inside the Perimeter; a few cities are split between the two codes. Both codes are now overlaid by 678, and 470. The metro Atlanta region (404, 770, 678, 470 and parts of 706/762 and 256/938) is a local calling area, and no long-distance charges are applied for calls from one portion of the metro to the other.
Currently, cell phone subscribers in the region can choose from either the 770 or 470 area code when signing up for service. When the area was originally divided in 1995, most cellphones stayed with 404, which balanced the fact that most of the landline area went to 770.
Atlanta was the first city in the United States to have mandatory 10-digit dialing throughout its metro area, roughly coinciding with the 1996 Summer Olympics in Atlanta. Atlanta was used as the test case not only due to its size, but also because it enjoyed the world's largest fiber optic bundle at the time (five times that of New York at the time), and it was home to BellSouth (now part of AT&T), then the Southeastern Regional Bell Operating Company.
Barrow, Bartow, Butts, Carroll, Cherokee, Clayton (part with area code 404), Cobb, Coweta, Dawson, DeKalb (part with area code 404), Douglas, Fayette, Forsyth, Fulton (part with area code 404), Gwinnett, Hall, Haralson, Heard (part with area codes 706 and 762), Henry, Lamar, Meriwether (part with area codes 706 and 762), Newton, Oconee, Paulding, Pike, Polk, Rockdale, Spalding, and Walton.
|Georgia area codes: 229, 404, 470/678, 478, 706/762, 770, 912|
|West: 256/938||area code 770 completely surrounds 404; entire region overlaid by 470 and 678||East: 706/762|
|South: 478, 706/762|
|Alabama area codes: 205, 251, 256/938, 334|