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Cos Cob, CT Area Codes
Cos Cob, Connecticut (population 7,354) uses area codes 203 and 475.
Cos Cob has no telephone exchange of its own in NANPA records; it is served by the Greenwich exchange about 3.7 km away.
Carriers with Cos Cob numbers
35 prefixes are assigned to the Greenwich exchange: 0% mobile, 37% VoIP and cable, 63% landline.
| Carrier | Prefixes |
|---|---|
| Verizon | 11 |
| Cablevision Lightpath | 6 |
| Onvoy (Sinch) | 4 |
| Csc Voice | 4 |
| Tc Systems | 2 |
| Paetec Itel | 2 |
| Lumen (Level 3) | 2 |
| Metropcs | 1 |
Area codes used in Cos Cob
| Area code | Prefixes serving Cos Cob | Main carriers in this code |
|---|---|---|
| 203 | 27 | Frontier, Verizon Wireless, AT&T Mobility |
| 475 | 8 | Onvoy (Sinch), Verizon Wireless, T-Mobile |
Cos Cob phone number prefixes
Numbers starting with these first six digits were originally assigned to the Greenwich exchange.
203-203Onvoy (Sinch)203-302Tc Systems203-340Cablevision Lightpath203-413Paetec Itel203-422Verizon203-485Cablevision Lightpath203-489Cablevision Lightpath203-496Metropcs203-542At&T - Local203-618Verizon203-622Verizon203-625Verizon203-629Verizon203-661Verizon203-717Csc Voice203-742Verizon Business (MCImetro)203-769Verizon203-861Verizon203-862Verizon203-863Verizon203-869Verizon203-900Csc Voice203-930Lumen (Level 3)203-971Cablevision Lightpath203-983Paetec Itel203-987Lumen (Level 3)203-992Csc Voice475-240Tc Systems475-278Cablevision Lightpath475-303Nuso475-335Onvoy (Sinch)475-383Onvoy (Sinch)475-500Onvoy (Sinch)475-509Cablevision Lightpath475-897Csc Voice
Nearby cities in area code 203
- Bridgeport
- Stamford
- New Haven
- Waterbury
- Norwalk
- Danbury
- Meriden
- West Haven
- Milford
- Shelton
- Naugatuck
- East Haven
Questions
- What is the area code for Cos Cob, CT?
- Cos Cob uses 2 area codes: 203 and 475. They overlay each other, so all of them cover the whole city and you dial 10 digits for local calls.
- What time zone is Cos Cob in?
- Cos Cob is in the Eastern time zone.