Area codes 317 and 463

Area code 317 is a North American Numbering Plan area code for central Indiana. It serves most of the Indianapolis metropolitan area, including Indianapolis itself and Marion County and all or part of Boone, Hancock, Hamilton, Hendricks, Johnson, Madison, Morgan, and Shelby counties. As of October 15th 2016, area code 463 is in service as an overlay to 317.

317 was one of the original area codes introduced in 1947. It originally covered the northern two-thirds of Indiana, while area code 812 served southern Indiana. In the first split of the area code system since its 1947 inception, northern Indiana received 219 the following year. Despite Indianapolis's rapid growth and increased number demand, no further changes were made to 317 until February 1, 1997, when most of the old 317 territory outside of the Indianapolis area switched to 765. As a result, the 317/463 numbering plan area (NPA) is the only one of Indiana's six NPAs that does not border another state.

The number pool for 317 was expected to exhaust in 2017. The Indiana Regulatory Commission announced that overlay area code 463 will be installed in 2016. The new area code, which coincidentally also spells out IND, will be assigned to new customers only, making 317 the second area to be overlaid in Indiana after 812 was overlaid with 930 in March 2015.

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