Area codes 317 and 463

The numbering plan area (NPA) comprises all or parts of Marion, Boone, Hancock, Hamilton, Hendricks, Johnson, Madison, Morgan, and Shelby counties.

[1] 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.

[2] The proliferation of pagers and cell phones depleted the numbering resources of area code 317, so that it was expected to exhaust in 2017.

The Indiana Regulatory Commission announced that area code 463 would be added in 2016 to form an overlay numbering plan.

[4] However, on August 31, in response to an appeal from security alarm companies, the deadline was extended to October 15, 2016.