Big Flats is a town in Chemung County, New York, United States. The population was 7,731 at the 2010 census. The town is on the west border of the county, west of Elmira. It is part of the Elmira Metropolitan Statistical Area. The town contains a hamlet also named Big Flats.
The town of Big Flats, which had formerly been called "Great Plains", was organized in 1822 from the town of Elmira.