Like many race drivers, the Geneva-based Canadian began his motorsport career in karting at the age of 10. He recorded numerous race and championship wins in his native Canada and North America and in 2008, his first year of karting, he won the Federation de Sport Automobile du Quebec rookie of the year award and driver of the year in 2009. In 2010, Stroll became a member of the Ferrari Driver Academy.

Stroll’s car racing debut came in the 2014 Florida Winter Series, a non-championship series organised by the Ferrari Driver Academy. He raced against future Formula One competitors Nicholas Latifi and Max Verstappen, and took two podium finishes as well as pole position at Homestead–Miami Speedway.

Stroll made his competitive car racing debut in the 2014 Italian F4 Championship, driving for Prema Powerteam. Despite missing the final round due to injury, Stroll emerged as series champion, taking seven race wins, thirteen podium finishes and five pole positions.

On 11 November 2015, it was announced that Stroll would leave the Ferrari Driver Academy to serve as a test driver for Williams.

Stroll began 2016 by finishing 5th at the 2016 24 Hours of Daytona, driving for Ford Chip Ganassi Racing in a Ford EcoBoost Prototype. He remained with Prema Powerteam for a third consecutive year to compete in his second season of the Formula 3 European Championship. He won the first race at Circuit Paul Ricard before taking thirteen more race victories over the season, including five consecutive victories in the final five races. He claimed the title with four races to go and ended the season 187 points clear of nearest competitor Maximilian Günther.

2018 got off to a rough start, with multiple incidents and mistakes within the first few races. Despite an 8th place in Azerbaijan, Stroll scored his next point at Monza, having failed to score at his home race in Canada when he crashed with Brendon Hartley. Although the FW41 was well off the pace all season, it was reliable as Stroll only retired from 2 races during the season.