Josh Cook battled fiercely for the 2014 Renault UK Clio Cup title, ultimately finishing as runner-up but winning more races than his rival, Mike Bushell. This success earned him a spot on the BTCC grid in 2015 with Power Maxed Racing, driving a Chevrolet Cruze. Cook had a strong rookie season, securing seven top ten finishes and a podium at Rockingham, and won the Jack Sears Trophy for top rookie.

In 2016, Cook joined the factory MG team, adding two more podiums to his record. The following year, he moved to Team Parker Racing, initially driving a Ford Focus before returning to MG machinery midway through the season.

In 2018, Cook joined Power Maxed TAG Racing, driving a Vauxhall and winning two races early in the season. He finished sixth overall with four additional podiums. The next year, he switched to BTC Racing, piloting a Honda Civic Type R to three victories and finishing fourth in the championship.

Cook continued with BTC Racing in 2020, securing another trio of wins and a consistent second half of the season, leading to a top ten finish. In 2021, he kicked off the campaign with a double victory at Thruxton and closed it with two more wins at Brands Hatch, finishing with five wins overall.

In 2022, Cook built on his success, winning five races and becoming the most successful BTCC driver at Thruxton. Despite some challenges, he secured four more podiums and finished sixth in the championship.

In 2023, Cook returned with BTC Racing, now One Motorsport with Starline Racing, and finished fifth in the championship, winning the Independent Drivers’ Championship as well.

In 2024, Cook and teammate Aiden Moffat moved to Speedworks, driving a Toyota Corolla for LKQ Euro Car Parts with SYNETIQ, aiming to enter the championship fight.