The Spinster Stakes (also known as the "Juddmonte Spinster" with Juddmonte Farms sponsorship) is an American Thoroughbred horse race for fillies and mares aged three or up run annually in early October at Keeneland Racecourse in Lexington, Kentucky. It is set at a distance of one and one-eighth miles and is a Grade I event with a current purse of $600,000. In time for the 2006 edition of the Spinster Stakes, Keeneland replaced its traditional dirt track with the synthetic surface, Polytrack synthetic dirt. In 2014, the Polytrack was replaced by a new dirt surface.