Below is a list of Old Greenwich CT zip codes. For your research we have also included Old Greenwich Area Code, Time Zone, UTC and the local Fairfield County FIPS Code. Each Old Greenwich Connecticut zip code has a center Longitude / Latitude point (the Old Greenwich center is -73.564903259277 / 41.022899627686). For your convenience we have also indicated if that zip code in Old Greenwich observes Daylight Savings time.