[1] 46 mushers participated in the race including past winners and noted racers Aliy Zirkle, Martin Buser, Dallas Seavey, Peter Kaiser, Joar Leifseth Ulsom, and Nicolas Petit.

[2] The 2021 Iditarod was won by Dallas Seavey, who finished on March 15 with a total race time of 7 days, 14 hours, 8 minutes, and 57 seconds.

On February 5, 2021, the race officials announced they had canceled the ceremonial start in Anchorage, which usually is an 11-mile (18 km) route through the city.

The rest of the route is then run back along preexisting trail, ending in the town of Willow.

The 2021 race rules require the mandatory 24 hour layover, which is used to equalize the time differences in starting positions, to be used at or before the Iditarod checkpoint.