List of counties in South Carolina in the context of Richland County, South Carolina

South Carolina (/ˌkærəˈlaɪnə/ KARR-ə-LY-nə) is a state in the Southeastern, South Atlantic and Deep South regions of the United States. It borders North Carolina to the north and northeast, the Atlantic Ocean to the southeast, and Georgia to the west and south across the Savannah River. Along with North Carolina, it makes up the Carolinas region of the East Coast. South Carolina is the 11th-smallest and 23rd-most populous U.S. state with a recorded population of 5,118,425 according to the 2020 census. In 2019, its GDP was $213.45 billion. South Carolina is composed of 46 counties. The capital is Columbia with a population of 136,632 in 2020; while its most populous city is Charleston with a 2020 population of 150,227. The Greenville-Spartanburg-Anderson, SC Combined Statistical Area is the most populous combined metropolitan area in the state, with an estimated 2023 population of 1,590,636.

South Carolina was named in honor of King Charles I of England, who first formed the English colony, with Carolus being Latin for "Charles". In 1712 the Province of South Carolina was formed. One of the original Thirteen Colonies, South Carolina became a royal colony in 1719. During the American Revolutionary War, South Carolina was the site of major activity among the American colonies, with more than 200 battles and skirmishes fought within the state. South Carolina became the eighth state to ratify the U.S. Constitution on May 23, 1788. A slave state, it was the first state to vote in favor of secession from the Union on December 20, 1860. After the Civil War ended, the state was readmitted to the Union on July 9, 1868.

Charleston County is located in the U.S. state of South Carolina along the Atlantic coast. As of the 2020 census, the population was 408,235, making it the third-most populous county in South Carolina (behind Greenville and Richland counties). Its county seat is Charleston. It is also the largest county in the state by total area, although Horry County has a larger land area. The county was created in 1800 by an act of the South Carolina State Legislature. Charleston County is included in the Charleston-North Charleston, SC Metropolitan Statistical Area. It is in the Lowcountry region of South Carolina.

Lexington County is a county located in the U.S. state of South Carolina. As of the 2020 census, the population was 293,991. Its county seat and largest community is Lexington. The county was chartered in 1785 and was named in commemoration of Lexington, Massachusetts, the site of the Battle of Lexington in the American Revolutionary War. Lexington County is the sixth-most populous county in South Carolina by population and is part of the Columbia, SC Metropolitan Statistical Area. It is located in the Midlands region of South Carolina.