Cornwallville is a hamlet in the town of Durham, Greene County, New York, United States.[1] The zipcode is: 12418.[2] Its estimated population in 2018 was 408.[3] Quick Facts Country, State ...Cornwallville, New YorkHamletCornwallvilleShow map of New YorkCornwallvilleShow map of the United StatesCoordinates: 42°22′05″N 74°09′29″WCountryUnited StatesStateNew YorkCountyGreeneTownDurhamElevation958 ft (292 m)Time zoneUTC-5 (Eastern (EST)) • Summer (DST)UTC-4 (EDT)ZIP code12418Area code518GNIS feature ID947485[1]Close [1]"Cornwallville, New York". Geographic Names Information System. United States Geological Survey, United States Department of the Interior.[2]United States Postal Service (2012). "USPS - Look Up a ZIP Code". Retrieved February 15, 2012.[3]BestPlaces entry. This article about a location in Greene County, New York is a stub. You can help Wikipedia by expanding it.vte