The 2016 Missouri Senate election was held on November 8, 2016, to determine which party would control the Missouri Senate for the following two years in the 99th Missouri General Assembly. All odd-numbered seats were up for election, which consisted of half of the 34 senate seats, as well as a special election for the 4th District following incumbent's Joseph Keavenyresignation after having been appointed administrative law judge at the Department of Labor on July 7, 2016. The primary was held on August 2, 2016. Prior to the election 25 seats were held by Republicans and 9 were held by Democrats. The general election saw both parties holding on to the same amount of seats as the previous election, meaning that Republicans retained control of the Missouri Senate.[1]