In March 2019, Chadwick was announced as one of the entrants for the inaugural season of the W Series, and followed this by participating in the opening three races of the 2019 F3 Asian Championship.
Chadwick was also announced as an official junior driver for Aston Martin Racing, extending an existing unofficial relationship that dated back to 2014.
At the first W Series race at Hockenheim, Chadwick put in a dominant performance, leading both practice sessions and qualifying on pole.
Despite briefly giving up the race lead to Alice Powell, Chadwick came from behind to take the first win in W Series history.
Two weeks later at Zolder, Chadwick again started on pole, however lost the lead to Beitske Visser from the start, and had to fight off Powell after locking up and running wide later in the race, ultimately holding onto second place.

Two days after the race in Zolder, Chadwick became the second driver to join the Williams Driver Academy, signing on as a development driver for the team.
In the next W Series race at Misano the following month, Chadwick qualified second behind Fabienne Wohlwend, but passed her on the start and held off pressure from Visser to take her second W Series win.
Chadwick then finished in third place behind Marta García and Visser at Norisring, after a long battle with the latter that saw her lose second place on the start and make a late lunge in an attempt to regain the place towards the end of the race.

At Assen, Chadwick started and finished in third after again holding off late pressure from Visser.
In the non-championship reverse grid race the following day, Chadwick fought through the field to finish eighth after starting from the back of the grid.
Chadwick then entered the 2019 24 Hours of Nürburgring with Aston Martin, racing alongside Alex Brundle and Peter Cate in the Aston Martin Vantage AMR GT4, finishing first in the SP8 class and twenty-seventh overall.
Chadwick entered the W Series championship decider at Brands Hatch with a 13 point lead on second placed Visser, and proceeded to start on pole for the third time.
Despite defending the lead initially, she lacked race pace and lost positions to Powell, Emma Kimiläinen and finally Visser, however her eventual fourth placed finish was enough to hold off Visser and win the inaugural W Series title.

In September, Chadwick joined Double R Racing to test drive their Euroformula Open car in Silverstone, with a view to a competitive drive in the series in the future.
The following week, Chadwick was announced as one of the competing drivers in the inaugural series of Extreme E in 2021.

In 2020 Chadwick was awarded her first 10 of the 40 points (of the 25 points for free practice) needed to qualify for a FIA Super License, having finished fourth overall in the 2019–20 F3 Asian Championship.

On 16 June 2020, it was announced that she had joined the Italian outfit Prema Powerteam, to be one of Prema's four drivers in the 2020 Formula Regional European Championship.
In March 2019, Chadwick was announced as one of the entrants for the inaugural season of the W Series, and followed this by participating in the opening three races of the 2019 F3 Asian Championship. Chadwick was also announced as an official junior driver for Aston Martin Racing, extending an existing unofficial relationship that dated back to 2014. At the first W Series race at Hockenheim, Chadwick put in a dominant performance, leading both practice sessions and qualifying on pole. Despite briefly giving up the race lead to Alice Powell, Chadwick came from behind to take the first win in W Series history. Two weeks later at Zolder, Chadwick again started on pole, however lost the lead to Beitske Visser from the start, and had to fight off Powell after locking up and running wide later in the race, ultimately holding onto second place.
Two days after the race in Zolder, Chadwick became the second driver to join the Williams Driver Academy, signing on as a development driver for the team. In the next W Series race at Misano the following month, Chadwick qualified second behind Fabienne Wohlwend, but passed her on the start and held off pressure from Visser to take her second W Series win. Chadwick then finished in third place behind Marta García and Visser at Norisring, after a long battle with the latter that saw her lose second place on the start and make a late lunge in an attempt to regain the place towards the end of the race.
At Assen, Chadwick started and finished in third after again holding off late pressure from Visser. In the non-championship reverse grid race the following day, Chadwick fought through the field to finish eighth after starting from the back of the grid. Chadwick then entered the 2019 24 Hours of Nürburgring with Aston Martin, racing alongside Alex Brundle and Peter Cate in the Aston Martin Vantage AMR GT4, finishing first in the SP8 class and twenty-seventh overall. Chadwick entered the W Series championship decider at Brands Hatch with a 13 point lead on second placed Visser, and proceeded to start on pole for the third time. Despite defending the lead initially, she lacked race pace and lost positions to Powell, Emma Kimiläinen and finally Visser, however her eventual fourth placed finish was enough to hold off Visser and win the inaugural W Series title.
In September, Chadwick joined Double R Racing to test drive their Euroformula Open car in Silverstone, with a view to a competitive drive in the series in the future. The following week, Chadwick was announced as one of the competing drivers in the inaugural series of Extreme E in 2021.
In 2020 Chadwick was awarded her first 10 of the 40 points (of the 25 points for free practice) needed to qualify for a FIA Super License, having finished fourth overall in the 2019–20 F3 Asian Championship. 
On 16 June 2020, it was announced that she had joined the Italian outfit Prema Powerteam, to be one of Prema's four drivers in the 2020 Formula Regional European Championship.
Jamie Chadwick