HARBOR SPG — MI
Data last updated: March 10, 2026
Area Codes
Top Carriers
| Carrier | OCN | NXX Count |
|---|---|---|
| MICHIGAN BELL TEL CO | 9323 | 2 |
| CENTURYLINK COMMUNICATIONS, LLC | 508J | 1 |
| ONVOY, LLCV - MI | 543C | 1 |
| SPOK, INC. | 6630 | 1 |
| TELEPORT COMMUNICATIONS AMERICA, LLC - MI | 770E | 1 |