If you've started shopping for a used car in the UK, you've almost certainly landed on AutoTrader and eBay Motors. They're the two biggest names in online car buying — but they work in completely different ways, and the right one for you depends on what you actually want.

The Quick Verdict

AutoTrader is the polished, dealer-dominated marketplace where most UK car buyers start. eBay Motors UK is the rougher, more diverse marketplace where you can find genuine bargains — if you know where to look. Most savvy buyers actually use both.

Inventory: Who Has More Cars?

AutoTrader is the UK's largest car marketplace by a comfortable margin. At any given time it lists hundreds of thousands of vehicles, the vast majority from franchised and independent dealers. If you want choice, AutoTrader is hard to beat.

eBay Motors UK is smaller in raw numbers but includes a healthy mix of private sellers and dealers. Crucially, eBay also includes auction-style listings — something AutoTrader doesn't offer. This is where the bargains lurk.

Pricing: Where the Real Bargains Are

Here's the honest truth: AutoTrader prices are very competitive at the dealer end, but private sellers on AutoTrader often pitch their cars optimistically. eBay's "Buy It Now" listings can be slightly cheaper, and auction listings can be dramatically cheaper if you're willing to bid carefully.

That said, eBay auction wins are notoriously variable. Some weeks you'll see a 2018 Ford Fiesta sell for hundreds below market value. Other weeks identical cars go for over the odds.

Trust and Safety

AutoTrader has a more mature buyer protection ecosystem. Most listings are dealers, which means they're regulated, VAT-registered, and held to the Consumer Rights Act 2015. Their built-in tools for vehicle history checks add reassurance.

eBay Motors is more buyer-beware. Private sellers come with no consumer protection rights, and you're responsible for your own due diligence. eBay's Vehicle Purchase Protection helps but has limits — never skip an HPI check on either site.

User Experience

AutoTrader's filtering is genuinely excellent. You can narrow by mileage, fuel type, body style, gearbox, owner count, distance from home, and a dozen other criteria. The mobile app is one of the best in UK retail.

eBay's car search is functional but feels older. The interface hasn't moved on much in years, and filtering is clunkier. That said, once you know which keywords to search for, it's a goldmine.

So Which Should You Use?

Use both. That's why we built Car Cupid — to save you the time of running the same search across multiple sites. Type your make, model and budget once, and we'll fire off matching searches on AutoTrader, eBay Motors, Cazoo, Cinch and Motors.co.uk simultaneously.

If you have to choose just one, AutoTrader is the safer first stop. But never make a final decision without checking eBay too — that's where the patient buyer can save four figures.