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.

Greenville is a city in and the county seat of Greenville County, South Carolina, United States. With a population of 70,720 at the 2020 census, it is the 6th-most populous city in the state. Greenville is located approximately halfway between Atlanta, Georgia, and Charlotte, North Carolina, along Interstate 85. Its metropolitan area also includes Interstates 185 and 385. Greenville is the anchor city of the Upstate, a combined statistical area with an estimated population of 1,590,636 in 2023. Greenville was the fourth fastest-growing city in the United States between 2015 and 2016, according to the U.S. Census Bureau.