Santino Ferrucci and Arjun Maini and both reported to be in the running to continue in development roles at Haas F1.
So far, Haas has not confirmed any test, development or reserve drivers for the 2018 season.
Ferrucci has already served as the team's development driver. He made his Formula 2 début in 2017 with Trident, after a season and a half in GP3 at DAMS.
Maini joined Haas midway through last year, sharing simulator duties with Ferrucci. He combined his role with a second season in GP3 with Jenzer Motorsport.
Neither driver has yet been handed a Grand Prix weekend free practice outing. However both now look likely to be retained in some capacity in 2018.
"Haas F1 Team is currently in discussions with Santino Ferrucci and Arjun Maini about their potential roles in 2018.
"Santino has been a part of the team since 2016 and Arjun joined last year," the team told Autosport magazine.
"The partnership has been beneficial for both drivers and for Haas F1 Team," the statement added.
"While it's something we're looking to continue in 2018, we're not ready to announce anything yet."
The team did announce a new commercial sponsorship this week, with menswear producers Jack & Jones.
The brand will appear on the rear wing of the team's cars, and on the firesuits worn by Romain Grosjean and Kevin Magnussen. Team members will be kitted out in the company's lifestyle apparel.
“We strive to be the best, just like Haas F1," said said Henning Nielsen, head of e-commerce and marketing at Jack & Jones. "That’s why we have supported Kevin Magnussen throughout his career and why we have decided to join Haas F1 Team this season.”
“We’re very proud to announce our new partnership with Jack & Jones," said team principal Guenther Steiner. "“While we are still relatively new in Formula One, our objectives and work ethic are very similar.
"The recognition Jack & Jones has in its marketplace is what we strive for in Formula 1."