Area code 212

Area codes 212 and 646 are the area codes for most of the borough of Manhattan in New York City in the North American Numbering Plan (NANP). By area, it is one of the smallest plan areas in North America. It is overlaid by area code 917, which covers the entirety of New York City.

Area code 212 is one of the original 86 area codes assigned by AT&T in 1947. It originally served the entire five-borough area of New York City.

On September 1, 1984, Brooklyn, Queens and Staten Island were split off as a new numbering plan area (NPA) with area code 718, leaving Manhattan and the Bronx the area code 212. In 1992, numbering plan area 718 was expanded to include the Bronx, while reducing NPA 212 to most of Manhattan. In 1992, the entire city was overlaid with area code 917, which was initially planned for only mobile service. Area code 212 was overlaid with area code 646 in Manhattan on July 1, 1999, when new 917 mobile numbers became scarce.

In November 2015, area code 332 was assigned as an additional overlay area code for Manhattan's numbering plan area 212, the fourth serving the area and the seventh serving New York City. It is expected to be installed in 2017, as area codes 212 and 646 are expected to run out of numbers in the third quarter of 2017.

One Manhattan neighborhood, Marble Hill, is not in the 212/646 area code but the 718/347/929 codes. Marble Hill, although legally a part of Manhattan to this day, was geographically severed from Manhattan by the construction of the Harlem River Ship Canal in 1895. It was physically connected to the Bronx in 1914 when the by-passed segment of the Harlem River was filled in. When the Bronx shifted to 718 in 1992, Marble Hill residents fought to stay in 212, but lost. Marble Hill's trunk is wired into the Bronx line, and it would have been too expensive for New York Telephone to rewire it.

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