The 2021 Xfinity 500 was a NASCAR Cup Series race held on October 31, 2021, at Martinsville Speedway in Ridgeway, Virginia. Contested over 501 laps -- extended from 500 laps due to an overtime finish, on the .526 mile (.847 km) short track, it was the 35th race of the 2021 NASCAR Cup Series season, the ninth race of the Playoffs, and final race of the Round of 8.