Kaylen Frederick competed in Europe full-time in the 2019 British Formula 3 with Carlin. He scored his first win during the first weekend at Oulton Park. A further win at Spa-Francorchamps and podiums at Snetterton and Silverstone lead him to finish 9th in the standings. Frederick remained in British F3 for 2020 where he scored nine victories and three more podiums. His successful season meant he was crowned 2021 British F3 champion. 

For 2021, Frederick progressed to the FIA Formula 3 Championship to drive for Carlin. He scored his first points at the Red Bull Ring but unfortunately due to injury and testing positive for Covid-19 he missed two rounds and ended the year in 22nd. For 2022, Frederick switched to Hitech Grand Prix and had a much more successful season by scoring points in 7 races. The American driver finished the season in 17th place overall. Frederick is set to move to ART Grand Prix for his third season in F3 in 2023.