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Indiana: History | Northern (219, 260, 269) Central (317, 463, 765) Southern (812, 930)

Central Indiana

Central Indiana (formerly NPA 317) is covered by three area codes (NPAs) and two Local Access Transport Areas (LATAs).
A portion of the Indianapolis LATA is in the northern Indiana 574 area code. Area code 317 was one of the initial area codes assigned in 1947 and was the first one split when area code 219 was created in 1948. Area code 463 overlaid 317 in 2016,

Calls within each LATA (except local calls) are carried by an "Intra-LATA" carrier (intra is within). Calls to another LATA are carried by an "Inter-LATA" carrier (inter is between). To identify their Intra-LATA carrier, customers may call 1+NPA+700-4141 (substituting their NPA for "NPA"). To identify their Inter-LATA carrier customers may call 1-700-555-4141.

Each exchange area is connected to a "tandem" for connection to other exchanges and the long distance networks. There are several tandem locations across central Indiana. The tandems are grouped together to form each LATA. Tandems in the Indianapolis LATA are located in Indianapolis, Crawfordsville, Kokomo, Lafayette, Logansport and Muncie.

Indianapolis LATA - 765
The largest portion of the Indianapolis LATA is served by the 765 area code.
Area code 765 was placed in service on February 1st, 1997. Permissive dialing ended June 25th, 1997.

As of April 2013 a new area code is not expected to be needed in the 765 area until winter of 2027.
(NPA 547 is potentially the new code. This code was preassigned in approximately 1995-98.)

See box below for details of the 1997 317 Area Code Split

Indianapolis LATA - 317/463
The central core of the Indianapolis LATA is served by the 317 area code.
Nearly every exchange area in the 317 area code is a local call from downtown Indianapolis.

On April 8, 2015, the Indiana Utilities Regulatory Commission authorized and overlay of area code 463 over the entire 317 area code. The overlay requires all local calls within the 317 area code to be dialed as 10 digits. Permissive dialing (7 or 10 digits allowed) began March 19, 2016, and was scheduled to end September 17th. Out of consideration for the Electronic Security Association, permissive dialing was extended to October 15th, 2016, and the new NPA became effective on November 15th, 2016.
(The 463 NPA spells "IND" and was preassigned in approximately 1995-98.)

The 1997 317 Area Code Split

The decision to split the 317 area code was made by the Indiana Utility Regulatory Commission (IURC). The original plan was later modified to keep Shelbyville in the 317 area code.

Cicero, Ninevah, Sheridan, Shelbyville and Marietta are the only exchanges in 317 that are not a local call from Indianapolis.

The industry's recommendation for relief was an overlay, allowing customers in central Indiana to keep their existing numbers but forcing all calls to be placed as 10 or 11 digit dialing. The IURC's decision allowed 7 digit local dialing to continue within the 317 and new 765 area codes, with local calls across area code boundries dialed as 10 digits and only long distance calls dialed as 11 digits.
More Information

Due to changes in how exchanges were assigned and other conservation measures, the life of 317 has been extended to 20 years. The life of 765 is now expected to be 45 years.

Richmond LATA
The Richmond LATA in east central Indiana is served by the 765 area code.
The tandem for the Richmond LATA is located in Richmond.

Written / Compiled for
Telecom Indiana