OLDGRNWICH — CT
Data last updated: March 10, 2026
Area Codes
Top Carriers
| Carrier | OCN | NXX Count |
|---|---|---|
| MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CT | 7230 | 5 |
| SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT | 9147 | 3 |
| ONVOY, LLC - CT | 639C | 2 |
| CABLEVISION LIGHTPATH, INC. - CT | 4950 | 1 |
| TELEPORT COMMUNICATIONS AMERICA, LLC - CT | 7143 | 1 |