317
Area code
IN
United States geographic area code, in service since 1947-01-01. Part of the 317/463 overlay complex — ten-digit dialing required.
Statusin service
Introduced1947-01-01
JurisdictionIN, US
Local dialing10D
Time zoneEastern
Last verified2026-09-17
Utilization 101% of assignable prefixes assigned
As of 09/17/2026
0%800 of ~792 assignable NXX values (200–999 excl. N11)100%
Prefix-level assignment does not equal number-level exhaustion; thousands-block pooling extends capacity. First assignment on record 2001-01-22, most recent 2026-09-15.
Area codes serve rate-center geographies, not municipal boundaries. “IN” identifies the jurisdiction, not an exact city footprint.
Top assignees
Ranked by assigned prefixes · initial assignee ≠ current carrier| Rank | Assignee | Prefixes | Share |
|---|---|---|---|
| 01 | INDIANA BELL TEL CO INC | 297 | 37.1% |
| 02 | OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC | 80 | 10% |
| 03 | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IN | 80 | 10% |
| 04 | NEW CINGULAR WIRELESS PCS, LLC - IL | 65 | 8.1% |
| 05 | LEVEL 3 COMMUNICATIONS, LLC - IN | 35 | 4.4% |
| 06 | PAETEC ITEL, LLC | 31 | 3.9% |
| 07 | TELEPORT COMMUNICATIONS AMERICA, LLC - IN | 25 | 3.1% |
| 08 | LEVEL 3 TELECOM OF INDIANA, LP - IN | 22 | 2.8% |
| 09 | BANDWIDTH.COM CLEC, LLC - IN | 22 | 2.8% |
| 10 | ONVOY, LLC - IN | 17 | 2.1% |
Important: these are initial assignees from NANPA CO-code records — the carrier a prefix was originally assigned to. Because of number portability, the current serving carrier of any individual number may differ.
Change history
Recorded events for this NPA- 2016-08-31 NPA 463 to Overlay NPA 317 (Indiana)
- 1947-01-01Area code 317 entered service.
Planning letters & orders
Primary documents| Date | Document | Subject |
|---|---|---|
| 2016-08-31 | PL-496 ↗ | NPA 463 to Overlay NPA 317 (Indiana) |
| 2015-05-13 | PL-482 ↗ | NPA 463 to Overlay NPA 317 (Indiana) |