The 2018 United States Senate special election in Mississippi took place on November 6, 2018, to elect a United States senator from Mississippi. The election was held to fill the seat vacated by Senator Thad Cochran when he resigned from the Senate, effective April 1, 2018, due to health concerns. Republican governor Phil Bryant appointed Cindy Hyde-Smith to fill the vacancy created by Cochran's resignation. Hyde-Smith sought election to serve the balance of Cochran's term, which expired in January 2021.