The website will take a daily feed of road tests, news and features, which have been repackaged to fit with the design of the Auto Trader website. In return, What Car? will have its car valuation service featured on the Auto Trader website.
The two websites have traditionally competed to reach automotive consumers but the companies now think there is a natural fit between their brands.
"It would be unreasonable of us to imagine that consumers looking to buy their next vehicle would do all their research on one website," Martyn Hammond, sales and marketing director for Auto Trader, said. "By knitting together our content with What Car?, we can provide a seamless service for car buyers which will speed up their purchase decision and therefore encourage them to look to our site to buy vehicles.
"We chose to partner with What Car? because it is the leader in the provision of motoring editorial. In particular, its strong association with the new car sector lets us broaden the appeal of our site and demonstrate to the trade our commitment to provide vehicle buyers with the full spectrum of choice, new cars or used."
Kevin Madden, publisher of whatcar.com, said: "Our business model has always been to deliver an effective advertising medium for our customers while offering the best motoring content to other businesses. This deal not only delivers a direct revenue from content supply but also offers us an opportunity to build advertising revenues via our valuations service."
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