PRESTON — MD
Data last updated: June 25, 2026
Area Codes
Top Carriers
| Carrier | OCN | NXX Count |
|---|---|---|
| CORE COMMUNICATIONS, INC.- MD | 2593 | 1 |
| ONVOY, LLC - MD | 876D | 1 |
| VERIZON MARYLAND, INC. | 9212 | 1 |
| COMMIO, LLC | 939H | 1 |
Data last updated: June 25, 2026
| Carrier | OCN | NXX Count |
|---|---|---|
| CORE COMMUNICATIONS, INC.- MD | 2593 | 1 |
| ONVOY, LLC - MD | 876D | 1 |
| VERIZON MARYLAND, INC. | 9212 | 1 |
| COMMIO, LLC | 939H | 1 |