Area codes 317 and 463 are North American Numbering Plan area codes for Indianapolis and nine surrounding counties in central Indiana. It covers all or part of Marion, Boone, Hancock, Hamilton, Hendricks, Johnson, Madison, Morgan, and Shelby counties. 317 is the original area code, while 463 is an overlay covering the same area, making ten-digit dialing mandatory for all calls in the region.
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, the northern third of Indiana, including South Bend, Gary and Fort Wayne, received 219 the following year. Despite Indianapolis's rapid growth during the second half of the 20th century, and the accompanying increased number demand, this configuration remained in place for 48 years. No changes were made to 317 until February 1, 1997, when most of the old 317 territory outside of the inner ring of the Indianapolis metropolitan area switched to 765.
This was intended as a long-term solution. However, due to the proliferation of cell phones and pagers, 317 was expected to exhaust in 2017. The Indiana Regulatory Commission announced that area code 463 would be added in 2016 as an overlay. The new area code, which spells out IND on a standard telephone keypad, made 317 the second Indiana area code to be overlaid after 812 was overlaid with 930 in March 2015.
463 entered service on March 15, 2016. On that date, a permissive dialing period began during which both seven- and ten-digit calls would be able to complete. Ten-digit dialing was originally to become mandatory in the Indianapolis area on September 15, 2016. However, on August 31, in response to an appeal from security alarm companies, the deadline was extended to October 15, 2016. Before then, 317 had been one of the few urbanized area codes without an overlay, making Indianapolis one of the few major cities where seven-digit dialing was still possible.
- http://www.sbc.com/gen/general?pid=1718&phase=check SBC information. Accessed May 11, 2006
- Russell, John. "New area code, mandatory 10-digit dialing, come to Central Indiana". Indianapolis Star. Retrieved 8 April 2015.
|West: 765||Area code 317 and 463||East: 765|
|South: 812 and 930|