<P> Area codes 212, 646 and 332 are area codes for most of the borough of Manhattan in New York City . By area, it is one of the smallest numbering plan areas in the North American Numbering Plan . These area codes are overlaid by area code 917, which covers the entirety of New York City . </P> <P> Area code 212 is one of the original 86 area codes assigned by AT&T in 1947, and served the entire five boroughs of New York City . It was chosen for the nation's most - populous (and presumably most - called) city since it was the shortest to dial on the rotary dialing phones of the time, which generated a series of clicks . Only five clicks (2 + 1 + 2 = 5) were required to dial New York, with six clicks to dial the next - largest cities, Los Angeles (213) and Chicago (312). This configuration remained for 37 years, until tone - based button dialing and the necessity of new area codes made the dialing length moot . </P>

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