HART — MI
Data last updated: March 10, 2026
Area Codes
Top Carriers
| Carrier | OCN | NXX Count |
|---|---|---|
| FRONTIER NORTH, INC. - MI | 0695 | 1 |
| 123.NET, LLC | 2550 | 1 |
| OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC | 2964 | 1 |
| TWILIO INTERNATIONAL, INC. | 506J | 1 |
| CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI | 6003 | 1 |