Ballston Spa is a village and the county seat of Saratoga County, New York, United States, located southwest of Saratoga Springs. It is part of the Capital Region. The population of the village, named after Rev. Eliphalet Ball, a Congregationalist clergyman and an early settler, was 5,111 at the 2020 census. Ballston Spa lies on the border of two towns, situated partly in the Town of Ballston and partly in the Town of Milton.