South Carolina ratified the United States Constitution on May 23, 1788. Its Senate seats were declared vacant in July 1861 owing to its secession from the Union. They were again filled from July 1868. The state's current U.S. senators are Republicans Lindsey Graham, serving since 2003, and Tim Scott, serving since 2013. Strom Thurmond was the state's longest-serving senator (1954–1956, 1956–2003).

List of senators

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