The 2018 United States Senate elections were held on November 6, 2018. Among the 100 seats, the 33 of Class 1 were contested in regular elections while 2 others were contested in special elections due to Senate vacancies in Minnesota and Mississippi. The regular election winners were elected to 6-year terms running from January 3, 2019, to January 3, 2025. Senate Democrats had 26 seats up for election, while Senate Republicans had 9 seats up for election.

The 2016 United States Senate elections were held on November 8, 2016. The presidential election, House elections, 14 gubernatorial elections, and many state and local elections were held concurrently.