Drivers Romain Grosjean and Kevin Magnussen are to remain at Haas for 2020.
Grosjean, currently 17th in the F1 drivers' championship, has been with the constructor from the start and will have a fifth season in their car.
Denmark's Magnussen, 26, joined a year after the 33-year-old French driver and is one place above him in 16th.
Haas are ninth in the constructors' championship, which would be their worst result since they joined F1.