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Which? Car Survey

Which? Car Survey explained

By Adrian Porter

Article 1 of 2

The 2017 Which? Car Survey is live. Tell us about your car and, whether you love or loathe it, you could win £2,500.

Put us to the test

Our Test Labs compare features and prices on a range of products. Try Which? to unlock our reviews. You'll instantly be able to compare our test scores, so you can make sure you don't get stuck with a Don't Buy.

Whether you’re after the best family car, best small car or best sports car, what makes a car great is that it gets you from A to B without breaking down.

While our in-depth lab tests reveal a car’s strengths and weaknesses, they won’t tell us what it’s like to live with – and that’s where you come in.

Every year, tens of thousands of people complete our annual Which? Car Survey. The information you provide is crucially important, as we use it to find the most reliable cars for sale.

£2,500Just by telling us about your car, you could win £2,500.

It also means we can warn people about the most unreliable vehicles – the ones that leave you stranded on the side of the road, with lots of time to contemplate the annual four-figure repair bill.

Once results are in, we update every car review with the latest reliability information. We also update our interactive car reliability checker.

To see the models that excelled in the Which? test lab, check out our Best Buy cars.

Finding the most reliable cars

Whether you’re buying a new car or something a little older, we can help you find a model you can rely on.

We dig as deeply as we can into each car’s track record, going back a maximum of eight years. To make sure we rate cars fairly, we classify every fault we hear about as one of the following:

Most-serious faults are major problems that are likely to result in a breakdown, are expensive to repair and likely to lead to the car being off the road for more than one day.

Serious faults are likely to result in a breakdown and will either be expensive to fix, or keep the car off the road for more than a day.

Medium-rated faults are likely to cause a breakdown, but not be expensive or time consuming to repair.

Less-serious faults are unlikely to require immediate repair work, but could still be costly to fix.

Least-serious faults are non-essential problems that require less than a day off the road, and are cheap to put right.

When manufacturers ask why a car has scored poorly in the survey, we share as much detail as we can to help them get to the root of a problem. So these results not only help us compare different cars, they also give carmakers a reason to keep evolving and improving their products.

Best cars to drive in the UK

Satisfaction counts for an awful lot when it comes to customer loyalty. A happy owner is likely to buy another car from the same manufacturer and wholeheartedly recommend it to others.

That’s precisely why our survey asks owners to rate (out of five) how satisfied they are with their car, and also how likely they are to recommend it to a friend. By combining the responses to these two questions, we’re able to award each car a customer score as a percentage.


Which? 2017 survey

The 2017 Which? Car Survey is now open and will run until 1 March 2017. By completing the survey, you'll not only help us find the most reliable cars in the UK, but you'll also have a chance to win to the big prize of £2,500.

But it's not just car reliability we the survey reveals - here are some interesting facts from the 2016 survey:

  • We received data on 67,432 cars in total, from 59,387 owners (some have more than one car).
  • Tesla, Porsche and budget-car maker Dacia were identified as the most satisfying makes of car.
  • Based on ownership figures, the most popular cars in the survey were the Honda Jazz (2008-2015) and Ford Fiesta (2008-).
  • The average repair bill for one popular car exceeded £550.
  • 46% of respondents had bought a new car in the past 12 months, and spent an average of £26,180.
  • People with large and estate cars do the most mileage, averaging more than10,000 miles. People with small cars or sports cars do the least, at just over 7,000 miles on average.