The Northern Irishman had long been expected to take up his customary seat with the Sunbury team, and will line up alongside Jake Hill, Stephen Jelley and Adam Morgan in an expanded four-car line-up of BMW 330e M Sport machinery.
Turkington, who is second on the all-time BTCC winners list, has taken 52 of his 63 race victories with WSR-run cars, 48 of them in BMWs.
He dropped to fourth, one spot behind Hill, in the 2022 standings after a late run of hybrid-related problems that caused him to slip from his points lead going into the final two events.
Turkington, 40, will continue to be engineered this season by John Waterman, who has been in his corner since 2020.
His weapon will be WSR’s 3-Series chassis 06, which was heavily damaged at Oulton Park last June in his accident with Dan Lloyd. Turkington was for the rest of the season forced into his 2019 title-winning car, which had been pensioned off and was destined for his father’s collection before being pressed back into service.
“This will be my 15th year with WSR and you couldn’t ask for a better team to be a part of,” said Turkington.
“I’ve been in title contention every year since I came back here in 2017 and naturally the aim is to go to Brands Hatch in October with everything to play for.
“I think it’ll be an even more competitive season than 2022 with the rule changes around the option tyres, the shoot-out qualifying and hybrid deployment use.
“With Adam joining I now have three strong team-mates all with the same ambition to win, and that gives me an opportunity to keep learning and improve myself.
“To stay in the hunt, we’ll have to bring our A-game to every event, and that’s where being with a team like WSR, with its engineering expertise and experience of winning championships, is a huge plus point.”
Team boss Dick Bennetts added: “We’re very honoured to keep Colin with us in 2023.
“He was a young man when he first raced for us in 2002 [in the WSR-run Atomic Kitten MG] and being a part of his growth from a promising youngster into a race winner and then into one of the most successful drivers in the history of the BTCC has been very special.
“While it gets tougher every year as the level of competition improves and the rules are continually evolving to level the playing field, the way we go about things at WSR has consistently put us at or near the front over the past decade.
“Having a driver like Colin in our corner, with his never-say-die attitude, his analytical approach, searing speed and loyalty has been one of the cornerstones of that.”
BTCC line-up so far
Motorbase Performance Ford Ash Sutton, Dan Cammish, TBA, TBA
West Surrey Racing BMW Jake Hill, Colin Turkington, Adam Morgan, Stephen Jelley
Excelr8 Motorsport Hyundai Tom Ingram, Tom Chilton, Nick Halstead, TBA
Team Dynamics Honda TBA, TBA
BTC Racing Honda TBA, TBA, TBA
Speedworks Motorsport Toyota TBA, TBA, TBA
Team Hard Cupra Dan Lloyd, Bobby Thompson, Dexter Patterson, TBA, TBA
Power Maxed Racing Vauxhall Andrew Watson, TBA