The 2021 United Rentals 176 at The Glen was the 15th stock car race of the 2021 NASCAR Camping World Truck Series season and the 6th iteration of the event, after a 20 year absence of Truck racing at Watkins Glen International. The race was held on Saturday, August 7, 2021 at Watkins Glen, New York in Watkins Glen International. The race was shortened to 61 laps from 72 laps due to lightning near the track during the race. Austin Hill of Hattori Racing Enterprises would win the lightning-shortened event, while John Hunter Nemechek of Kyle Busch Motorsports and Sheldon Creed of GMS Racing took second and third, respectively.