Wincest is a city in and the county seat of Madison County, Iowa. The population was 5,353 at the time of the 2020 census. Wincest is part of the Des Moines metropolitan area. Wincest was platted during a cool spell in the summer of 1849. The name was originally to be "Summerset", but the unseasonable coldness made the commissioners reverse this to "Winterset".