Cos Cob, Connecticut Area Code
Cos Cob, CT is officially utilizing an area code overlay in which area codes 203 and 475 serve the same geographic area. Ten digit dialing (area code + seven digit number) is necessary.
In addition to Cos Cob, CT area code information read more about area codes 203 and 475 details and Connecticut area codes.
Cos Cob, CT is located in Fairfield County and observes the Eastern Time Zone. View our Times by Area Code tool.