Area codes 201 and 551 are area codes for New Jersey. Area code 201 was one of the first area codes created in October 1947. It is the lowest-numbered area code possible. It initially covered the entire state, but after it was split by 609 in 1956, 908 and 1991, and 732 in 1997, it now covers the northeasternmost section of the state, typically in the Hudson and Bergen counties, right next to the Hudson River and New York City. It was overlaid by area code 551 in 2001.
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