Roman Stanek will remain in the FIA Formula 3 Championship in 2021, making the switch to Hitech GP after his first full season in the series last year.
The Czech driver was a late call-up to Charouz in 2020, completing the entire season with the team and scoring a best result of eighth at Monza.
Stanek will join Red Bull juniors Jak Crawford and Ayumu Iwasa at the team, who were both confirmed last week.
“I’m grateful for the opportunity to join Hitech in FIA F3 and Asian F3,” Stanek said.
“The Asian F3 season opener will get underway in a couple of weeks, so I am looking forward to getting back out in the car after a long break.
“I’m really excited to work with a new team and will be putting in the hard work for a successful season.”
Stanek’s step up to F3 last year came after he won the rookie title in the 2019 ADAC Formula 4 Championship, as well as finishing fifth in the Italian F4 series.
He will also compete in the 2021 Asian F3 Championship with Hitech, which is set to get underway in later this month at the Yas Marina Circuit in Abu Dhabi.
Hitech Team Principal Oliver Oakes said: “We are delighted to have Stanek on board as we embark on what we hope will be another successful season.
“We always look forward to working with new drivers, and Stanek has shown the talent required in FIA F3 and Asian F3.”