Fort Mill, also known as Fort Mill Township, is a town in York County, South Carolina, United States. It is a suburb of Charlotte, North Carolina. As of the 2020 census, the population of the town was 24,521. Some businesses and residents in the Indian Land community of neighboring Lancaster County share a Fort Mill mailing address, but the official town boundary extends only within York County.

York County is a county on the north central border in the U.S. state of South Carolina. As of the 2020 census, the population was 282,090, making it the seventh-most populous county in the state. Its county seat is the city of York, and its most populous community is Rock Hill. The county is served by one Interstate Highway, Interstate 77.