The Czech squad has confirmed an all new line-up for this year with Beckmann graduating from FIA F3, while Samaia joins following an F2 season at Campos Racing.
The pair replace Pedro Piquet and Louis Deletraz, who drove for the team last year.
Beckmann makes the step up to F2 after finishing sixth in the 2020 FIA Formula 3 Championship, his second season in FIA F3, having recorded two victories and five podiums.
The 20-year-old German has already experienced the Charouz F2 car following an outing in the post-season test in Bahrain last year.
“I’m delighted to be able to jump into the FIA Formula 2 this year after developing my career in Formula 3,” said Beckmann.
“It’s exciting to have in front of me a new car and a new challenge, which reminds me the step I took from F4 to F3, and this will be really challenging.
“Of course, it’s also one more step towards Formula 1, and this means to see your goal a little bit closer.
“To be with Charouz Racing System in this venture makes me feel really comfortable: since they joined the FIA Formula 2, they showed to be on the spot, managing to be competitive and consistent in performance with all their drivers.
“The team has a great back-up and structure, I have already met during testing some of the personnel, which includes people I have already worked with previously and this put me totally at ease with the team and promises a good season together.”
This will be the Samaia’s second season in F2 after a challenging rookie campaign that yielded a best finish of 14th at Monza.
The Brazilian has plenty of open wheel experience having won the Brazilian F3 title in 2017, alongside stints in BRDC F3 and the Euroformula Open series.
“I am extremely happy to have joined Charouz Racing System for the 2021 season,” said Samaia. “They gave me a great opportunity at the end of the 2020 season to rebuild and show what we can do out at the track.
“The team brought me into high energy once again with a strong post season test, we did together. I am truly grateful to have been brought in in such an incredible group of people. I am confident we will be a very tough team this year. We will push very hard.”
Only three seats are yet to be confirmed on the F2 grid with Trident and MP Motorsport yet to complete their line-ups.
The F2 season begins in Bahrain on 26-28 March.
F2 2021 grid so far:
Prema Racing: Robert Shwartzman, Oscar Piastri
UNI-Virtuosi: Felipe Drugovich, Guanyu Zhou
Carlin: Jehan Daruvala, Dan Ticktum
Hitech Grand Prix: Juri Vips, Liam Lawson
ART Grand Prix: Theo Pourchaire, Christian Lundgaard
MP Motorsport: Lirim Zendeli, TBA
Charouz Racing System: David Beckmann, Guilherme Samaia
DAMS: Marcus Armstrong, Roy Nissany
Campos Racing: Ralph Boschung, Gianluca Petecof
HWA Racelab: Matteo Nannini, Alessio Deledda
Trident: TBA, TBA