Simpsonville is a city in Greenville County, South Carolina, United States. It is part of the Greenville, SC Metropolitan Statistical Area. The population was 23,354 at the 2020 census, up from 18,238 in the 2010 census. Simpsonville is part of the "Golden Strip", along with Mauldin and Fountain Inn, an area which is noted for having low unemployment due to a diversity of industries including H.B. Fuller, KEMET, Sealed Air and Milliken. It is the 23rd-most populous city in South Carolina.

Greenville County is located in the U.S. state of South Carolina. As of the 2020 census, the population was 525,534, making it the most populous county in the state. Its county seat is Greenville. The county is also home to the Greenville County School District, the largest school system in South Carolina.