The numbering plan area (NPA) includes Evansville and most of its suburbs, the Indiana portions of the Louisville and Cincinnati metropolitan areas, and the cities of Bedford, Bloomington, Columbus, Greensburg, Jasper, Princeton, Seymour, Terre Haute, and Vincennes. The NPA also serves a small section of Kentucky located adjacent to Evansville and north of the Ohio River whose most notable landmark is Ellis Park Race Course, a Thoroughbred horse racing track.
In 1947, American Telephone and Telegraph (AT&T) published the first configuration of proposed numbering plan areas (NPAs) for a new nationwide numbering and toll call routing system. Indiana was divided to receive two area codes. Area code 317 served the northern two-thirds of Indiana, while area code 812 served the southern third.
Despite the presence of Evansville, Terre Haute and Bloomington, southern Indiana is not as densely populated as the rest of the state. As a result, this configuration remained in place for more than six decades, making 812 one of the few original area codes (not counting those covering an entire state) that still had its original boundaries.
On July 31, 2013, it was announced that 812 would be overlaid with area code 930, the state's first overlay. The move came because 812 was expected to exhaust in 2015. The number shortage was exacerbated by the proliferation of cell phones, particularly in Evansville and the Louisville and Cincinnati suburbs. On March 1, 2014, a six-month permissive dialing period began, during which it was possible to complete calls within the 812 area with both seven and ten digits.
Mandatory ten-digit dialing was originally planned for September 6, 2014, with the first 930 numbers to become available in October. However, in August, the Indiana Utility Regulatory Commission delayed the implementation of mandatory ten-digit dialing until February 7, 2015, and the assignments of the first 930 numbers until March 7 to provide law enforcement and emergency medical services more time to update their telecommunication equipment.
- Counties (partial)
- Counties (entirely)
- Fort Branch
- Lincoln City
- Mount Vernon
- New Albany
- New Harmony
- New Salisbury
- North Vernon
- Oakland City
- Rising Sun
- Santa Claus
- Tell City
- Terre Haute
- "Ellis Park Racing & Gaming Home Page". Retrieved April 2, 2021.
- https://www.nationalnanpa.com/pdf/PL_457.pdf NANPA Planning Letter 457
- "2011-1 NRUF and NPA Exhaust Analysis" (PDF). North American Numbering Plan Administration. April 2011.
- Orr, Susan (July 31, 2013). "Say hello to your new area code, Southern Indiana: 930". Evansville Courier & Press.
- "NPA 930 to Overlay NPA 812 (Indiana)" (PDF). North American Numbering Plan Administration. September 3, 2013.
- White, Charlie (January 13, 2015). "10-digit dialing starts Feb. 7 in Indiana". Indianapolis Star.
- "Officials remind southern Indiana about 10-digit dialing changes". WLKY. January 8, 2015.
- Daudelin, Drew (February 5, 2015). "Mandatory 10-Digit Dialing In 812 Area Begins Saturday". WFIU.
|North: 317, 765|
|West: 217, 618||area code 812/930||East: 513, 859|
|South: 270/364, 502|
|Illinois area codes: 217, 224/847, 309, 312, 331/630, 618, 708, 773, 779/815, 872|
|Kentucky area codes: 270/364, 502, 606, 859|
|Ohio area codes: 216, 330/234, 419/567, 440, 513, 614/380, 740/220, 937/326|