918
Area code
OK
United States geographic area code, in service since 1953-01-01. Part of the 539/918 overlay complex — ten-digit dialing required.
Statusin service
Introduced1953-01-01
JurisdictionOK, US
Local dialing10D
Time zoneCentral
Last verified2026-09-17
Utilization 100.9% of assignable prefixes assigned
As of 09/17/2026
0%799 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 2001-01-16, most recent 2025-03-10.
Area codes serve rate-center geographies, not municipal boundaries. “OK” identifies the jurisdiction, not an exact city footprint.
Top assignees
Ranked by assigned prefixes · initial assignee ≠ current carrier| Rank | Assignee | Prefixes | Share |
|---|---|---|---|
| 01 | SOUTHWESTERN BELL | 236 | 29.5% |
| 02 | NEW CINGULAR WIRELESS PCS, LLC - IL | 93 | 11.6% |
| 03 | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - OK | 50 | 6.3% |
| 04 | T-MOBILE USA, INC. | 49 | 6.1% |
| 05 | VALOR TELECOM TX.LP-OK DBA WINDSTREAM COMM SW | 36 | 4.5% |
| 06 | UNITED STATES CELLULAR - OK | 32 | 4% |
| 07 | ONVOY, LLC - OK | 29 | 3.6% |
| 08 | LEVEL 3 COMMUNICATIONS, LLC - OK | 27 | 3.4% |
| 09 | COMCAST IP PHONE, LLC | 18 | 2.3% |
| 10 | CROSS WIRELESS, L.L.C. | 16 | 2% |
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- 2010-03-01 NPA 539 to Overlay NPA 918 (Oklahoma)
- 1953-01-01Area code 918 entered service.
Planning letters & orders
Primary documents| Date | Document | Subject |
|---|---|---|
| 2010-03-01 | PL-403 ↗ | NPA 539 to Overlay NPA 918 (Oklahoma) |