The 2017 St. Louis mayoral election was held on April 4, 2017, to elect the mayor of St. Louis, Missouri. Incumbent Mayor Francis Slay chose not to run for reelection. Slay, who was serving his fourth term as mayor, indicated in March 2016 that he would run for reelection, but announced in April 2016 that he would not run for a fifth term. Primary elections took place on March 7, 2017, and the general election was held on April 4. Alderwoman Lyda Krewson was elected and became the first female Mayor of St. Louis.