Mauldin is a city in Greenville County, South Carolina, United States. The population was 24,724 at the 2020 census, making it the 19th-most p…Mauldin is a city in Greenville County, South Carolina, United States. The population was 24,724 at the 2020 census, making it the 19th-most populous city in South Carolina. It is located in the Greenville-Anderson-Greer, SC Metropolitan Statistical Area.