The Haas VF-21 is powered by the 2021 Ferrari power unit, the 065/6. The chassis, as it was raced at the Bahrain Grand Prix, was identical to the VF-20 except for the downforce cuts mandated by the 2021 regulations. Haas introduced an upgrade package for the chassis at the Emilia Romagna Grand Prix, which will be the one and only change to the chassis in 2021. The upgrade package was not significant enough to require spending development tokens (introduced for development from 2020 to 2021 as a cost-saving measure), meaning Haas was the only constructor not to make any significant changes to its 2020 vehicle. The VF-21 chassis used in the 2021 season are modified VF-20 chassis, rather than new vehicles.