FREDERICK — MD
Data last updated: June 25, 2026
Area Codes
Top Carriers
| Carrier | OCN | NXX Count |
|---|---|---|
| VERIZON MARYLAND, INC. | 9212 | 28 |
| CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD | 6395 | 17 |
| NEW CINGULAR WIRELESS PCS, LLC - DC | 4036 | 7 |
| OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC | 6855 | 6 |
| ONVOY, LLC - MD | 876D | 6 |