Area Code 317
Indiana
Area code 317 serves Indiana, primarily Indianapolis, in the Eastern Time (ET) time zone. It has served the region since 01-Jan-1947.
Published: Last reviewed: Verified against NANPA and FCC records
Overlay Area Code
This area code shares its geographic footprint with an overlay code, so the same cities are served by two area codes. Because overlays leave existing numbers untouched, this region's relief planning favors adding codes over redrawing boundaries.
The codes serving this same region: area code 463 (Fishers).
With prefix utilization already at 98.3%, numbering resources here are under sustained pressure — context that explains why overlays were introduced.
In service since: 01-Jan-1947
Area Code Splits
One area code has been carved out of this code's original territory through a geographic split. Each split was a relief action: as demand grew, part of the region was reassigned to a new code rather than overlaying the whole territory.
Split into: area code 765 (Lafayette).
Demographics & Economics
- Total Population
- 2,659,754
- Population Density
- 413 people/sq miabove U.S. average (U.S.: 95 people/sq mi)
- Median Household Income
- $79,429near U.S. median (U.S.: $80,734)
- Poverty Rate
- 10.0%below U.S. average (U.S.: 12.5%)
- Unemployment Rate
- 3.8%below U.S. average (U.S.: 5.2%)
- Education Attainment
- Bachelor's Degree+39.9%above U.S. average (U.S.: 35.7%)High School or Lower28.9%
Statistics are population-weighted aggregations from Census ACS 5-year estimates. Population figures are approximate — see Sources & Methodology for details on how area code populations are derived.
See how this area code compares to all US area codes in the income ranking and density ranking.
Time Zone
- Eastern Time (ET)
NANPA Relief Status
According to the latest NANPA analysis (July 2026), this area code is not currently listed as exhausting within the next 36 months. No relief planning is in progress for this NPA.
Source: NANPA NPA Relief Planning Reports · See all relief planning statuses
Current Time
Prefix Utilization
Geographic Coverage
State
IN
Major Cities
- Indianapolis
- Fishers
- Carmel
- Noblesville
- Greenwood
- Westfield
- Lawrence
- Plainfield
- Zionsville
- Brownsburg
- Marion
- Franklin
- Greenfield
- Avon
- Shelbyville
- Lebanon
- Beech Grove
- Speedway
- Whitestown
- Danville
- Bargersville
- McCordsville
- Mooresville
- Cumberland
and 54 more cities
Historical Timeline of Area Code 317
Area code 317 was created in 1947 as one of the original 77 US NANP area codes, initially serving the northern two-thirds of Indiana. In 1948, it became the site of the first area code split in the United States when 219 was carved out for northern Indiana. A 1997 donut split created area code 765, preserving Indianapolis in 317 while assigning surrounding territory outward. After number conservation efforts extended its lifespan by over a decade, a 463 overlay was approved in 2015 and entered service in 2016. Source: NANPA
Key milestones:
- 1947: Created as one of the original 77 US area codes. Served northern two-thirds of Indiana, with area code 812 covering the south. Indianapolis was the largest city in the NPA. Source: Telecom Indiana
- 1948: First area code split in the United States: 317 was split to create area code 219 for northern Indiana (Gary, Hammond, South Bend, Fort Wayne). 317 retained central Indiana and Indianapolis. Source: Telecom Indiana
- 1997: Area code 765 split from 317 on February 1 in a "donut split" keeping the Indianapolis core in 317 while surrounding territory was assigned to 765. Source: NANPA
- 2000: 317 projected to exhaust in 2002, but 1,000-block number pooling introduced at the state level in 2001 extended lifespan by more than a decade. Source: IURC Cause No. 44513
- 2014: NANPA filed petition July 10 with IURC (Cause No. 44513) for 317 NPA relief. Industry consensus reached at May 29 planning meeting. Five public field hearings held September through October 2014. Source: IURC
- 2015: IURC approved all-services distributed overlay on April 8 (Cause No. 44513). New area code 463 assigned. 13-month implementation schedule approved. Projected overlay life: 49 years. Source: IURC Press Release
- 2016: 463 overlay entered service March 15. Mandatory 10-digit dialing took effect October 15 (extended from September 15 due to security alarm company appeal). First 463 numbers assigned October 17. Source: OUCC
Regulatory History
Area code 317's regulatory history centers on Indiana Utility Regulatory Commission IURC Cause No. 44513, approved April 8, 2015, which authorized the all-services distributed overlay of 317 with new area code 463. Indiana's primary telecom regulator is the IURC, not the FCC directly, though FCC oversight applies at the national NANP level. Source: IURC Press Release
| Year | Event | Docket | Regulatory Action & Impact |
|---|---|---|---|
| 1947 | NANP Inception | AT&T / Bell System | Area code 317 established as one of the original 77 US NANP area codes, assigned to IN. |
| 2014 | Industry planning meeting | Cause No. 44513 | Consensus reached for all-services distributed overlay after evaluating three alternatives: all-services distributed overlay, concentrated Indianapolis-only, and concentrated Indianapolis plus adjacent rate centers. IURC |
| 2014 | NANPA petition filed | Cause No. 44513 | NANPA filed verified petition with IURC on July 10 for 317 NPA relief, recommending all-services distributed overlay. IURC |
| 2014 | Public field hearings | Cause No. 44513 | Five hearings held September through October across the Indianapolis metropolitan area to gather public input on proposed relief alternatives. IURC |
| 2015 | IURC evidentiary hearing | Cause No. 44513 | Commission found industry thoroughly discussed pros and cons of each alternative at hearing held February 10, 2015. IURC |
| 2015 | Joint proposed order submitted | Cause No. 44513 | AT&T Indiana, OUCC, and IBTA jointly submitted proposed order recommending all-services distributed overlay on March 10, 2015. IURC |
| 2015 | Overlay approved | Cause No. 44513 | IURC approved all-services distributed overlay on April 8. New area code 463 assigned. 13-month implementation schedule. Projected overlay life: 49 years. IURC Press Release |
| 2016 | 463 overlay entered service | N/A | Permissive 10-digit dialing period began March 15, 2016, allowing existing 317 subscribers to continue using 7-digit dialing during transition. (NANPA) |
| 2016 | Mandatory 10-digit dialing | N/A | Extended from September 15 to October 15 due to security alarm company appeal for additional equipment update time. OUCC |
| 2016 | First 463 numbers assigned | N/A | New lines in the 317 region may receive either 317 or 463 area codes. 317/463 region not expected to need additional area code changes until approximately 2065. OUCC |
County Coverage
Population-weighted county share based on aggregated ZCTA population (100% = total mapped population for area code 317).
| County | Population | Share |
|---|---|---|
| Marion, IN | 1,051,180 | 39.5% |
| Hamilton, IN | 554,112 | 20.8% |
| Hendricks, IN | 244,810 | 9.2% |
| Hancock, IN | 181,001 | 6.8% |
| Johnson, IN | 176,464 | 6.6% |
| Shelby, IN | 143,943 | 5.4% |
| Boone, IN | 119,500 | 4.5% |
| Madison, IN | 67,614 | 2.5% |
| Morgan, IN | 61,639 | 2.3% |
| Rush, IN | 42,927 | 1.6% |
| Brown, IN | 9,085 | 0.3% |
| Clinton, IN | 6,924 | 0.3% |
| Henry, IN | 555 | 0.0% |
Area Code 317 Family Tree
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Area code 317 was originally assigned in 01-Jan-1947 to serve IN. Over the years, it has generated 2 descendant area codes through a combination of geographic splits and overlays as demand for telephone numbers grew.
Call Context
This area code covers a metropolitan region in IN with moderate to high population density, centered on Indianapolis and surrounding communities.
Nearby Area Codes
Area codes geographically closest to 317.
Other Area Codes in Indiana
Area codes that also serve Indiana, linked for easy comparison.