Hot Springs is a city in Fall River County, South Dakota, United States. As of the 2010 census, the city population was 3,711. It is the county seat of Fall River County. In addition, neighboring Shannon County contracts the duties of Auditor, Treasurer and Register of Deeds to the Fall River County authority in Hot Springs. Hot Springs is one of the warmest places in South Dakota with an annual mean temperature of 48.6 °F (9.2 °C).