Area codes 610 and 484

Area codes 610 and 484 are telephone area codes which serve the eastern and southeastern regions of Pennsylvania. The area includes areas to the west of Philadelphia, along with the cities of Allentown, Bethlehem, and Reading. It includes much of the Delaware Valley, including almost all of Delaware County and most of the Philadelphia Main Line.

Area code 610 was created on January 8, 1994 as a split from numbering plan area 215, which had been the entire southeast quadrant of Pennsylvania since 1947. Permissive dialing of both 215 and 610 continued until the morning of January 7, 1995. It was Pennsylvania's first new area code since the implementation of the area code system in 1947.

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