734
Area code
MI
United States geographic area code, in service since 1997-12-13. Part of the 679/734 overlay complex — ten-digit dialing required.
Split from 313.
Statussuspended
Introduced1997-12-13
JurisdictionMI, US
Local dialing7D
Time zoneEastern
Last verified2026-09-17
Utilization 92% of assignable prefixes assigned
As of 09/17/2026
0%729 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 2026-03-04.
Area codes serve rate-center geographies, not municipal boundaries. “MI” identifies the jurisdiction, not an exact city footprint.
Top assignees
Ranked by assigned prefixes · initial assignee ≠ current carrier| Rank | Assignee | Prefixes | Share |
|---|---|---|---|
| 01 | MICHIGAN BELL TEL CO | 161 | 22.1% |
| 02 | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI | 71 | 9.7% |
| 03 | OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC | 55 | 7.5% |
| 04 | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MI | 52 | 7.1% |
| 05 | PAETEC ITEL, LLC | 42 | 5.8% |
| 06 | LEVEL 3 COMMUNICATIONS, LLC - MI | 42 | 5.8% |
| 07 | ONVOY, LLCV - MI | 41 | 5.6% |
| 08 | NEW CINGULAR WIRELESS PCS, LLC - IL | 41 | 5.6% |
| 09 | TELEPORT COMMUNICATIONS AMERICA, LLC - MI | 37 | 5.1% |
| 10 | TELNET WORLDWIDE, INC. | 31 | 4.3% |
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- 1997-12-13Area code 734 entered service (created from 313).
Planning letters & orders
Primary documents| Date | Document | Subject |
|---|---|---|
| 1997-05-30 | PL-066 ↗ | NANP-Split of 313 (Michigan) Numbering Plan Area (NPA) |