Area codes 317 and 463

Area codes 317 and 463 are telephone area codes in the North American Numbering Plan (NANP) for Indianapolis and nine surrounding counties in central Indiana. The numbering plan area (NPA) comprises all or parts of Marion, Boone, Hancock, Hamilton, Hendricks, Johnson, Madison, Morgan, and Shelby counties. 317 is the original area code of the NPA, created in 1947, while 463 is an overlay code for the same area that was added in 2016, making ten-digit dialing mandatory for all calls in the region.