Used test: BMW 3 Series vs Mercedes-Benz C-Class

What will they cost?

Both cars will cost you roughly the same to buy; the Mercedes C-Class might be a smidge pricier, but in real terms the difference in price between the two cars is minimal.

It is worth keeping in mind that the BMW 3 Series is more ubiquitous, so the chances are it’ll be a little easier to find. That said, if you want an automatic gearbox, as fitted to our test cars, that changes, because the majority of 3 Series are manual.

The 3 Series is the cheaper of the two cars to fuel, too, with an official average figure of 62.8mpg; the C-Class is a little way off, its 58.9mpg figure suggesting there’ll be a noticeable difference between the two cars' real-world economy.

There’s a big difference between the tax costs of the two cars, too. The 3 Series' lower emissions mean it slips into tax band C, so it’ll cost £30 a year at current rates. However, the C-Class has to make do with tax band D – and as a result, its annual tax rate is £115.

There’s more bad news for C-Class owners when it comes to servicing costs, because here, too, the 3 Series is cheaper. Furthermore, aftermarket maintenance and repairs also look to be a little more cost-effective on the 3 Series.

As if that weren’t enough, the 3 Series has a better reliability record than the C-Class. In our most recent reliability survey, the 3 Series achieved a score of 82.5% – significantly better than the C-Class’s 69.7% rating.