436
Area code
OH
United States geographic area code, in service since 2024-03-01. Part of the 436/440 overlay complex — ten-digit dialing required.
Split from 440.
Statusin service
Introduced2024-03-01
JurisdictionOH, US
Local dialing10D
Time zoneEastern
Last verified2026-09-17
Utilization 1.8% of assignable prefixes assigned
As of 09/17/2026
0%14 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 —, most recent —.
Area codes serve rate-center geographies, not municipal boundaries. “OH” identifies the jurisdiction, not an exact city footprint.
Top assignees
Ranked by assigned prefixes · initial assignee ≠ current carrier| Rank | Assignee | Prefixes | Share |
|---|---|---|---|
| 01 | MULTIPLE OCN LISTING | 9 | 64.3% |
| 02 | 5 | 35.7% |
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- 2023-02-16 NPA 436 to Overlay NPA 440 (Ohio)
- 2024-03-01Area code 436 entered service (created from 440).
Planning letters & orders
Primary documents| Date | Document | Subject |
|---|---|---|
| 2023-02-16 | PL-610 ↗ | NPA 436 to Overlay NPA 440 (Ohio) |