Area code 609

Area code 609 serves telephones in southeastern and central New Jersey, including the cities of Trenton, Long Beach Island, Princeton, Hamilton and Atlantic City. In terms of geographic coverage, it is the largest in the state of New Jersey.

In the original North American Numbering Plan (NANP), all of New Jersey was served by area code 201, until it was split in 1958 to create area 609. This division generally followed the dividing line between North Jersey, dominated by proximity to New York City and South Jersey with its proximity to Philadelphia and the Jersey Shore.

In 1999, the southwestern part of area 609, the area adjacent to Philadelphia, was split off as area code 856. Since that time, the 609 territory covers parts of Central Jersey, South Jersey and the Jersey Shore, and many parts of Burlington County. It also includes portions of southern Middlesex County in Plainsboro, Cranbury, parts of South Brunswick (particularly Kingston) and the extreme southern part of Monroe. The boundary was drawn in such a way so that several towns were split between area codes. Some prefixes assigned to mobile phone providers that lie within the 856 territory have never had their area code changed; thus 609 serves as a de facto partial overlay of 856, although it is rarely acknowledged as such.

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