The Sinquefield Cup 2025, the fifth and final event of the Grand Chess Tour (GCT) 2025, is held from August 18 to August 28, 2025, at the Saint Louis Chess Club in St. Louis, Missouri, USA. It’s a 10-player single round-robin tournament with a classical time control of 90 minutes for forty minutes, plus 30 minutes for the rest of the game plus a 30-second increment per move.