A reliable car is one you can trust - it won't let you down. But no amount of test drives or chats with your local car dealer will tell you how reliable a car really is.
Every year we survey thousands of drivers to find out if they've had any problems with their car. These can range from minor issues to catastrophic failures. We then use the results to identify which brands make the most reliable cars. And the least.
Use our tool below to see the common faults, breakdown rates and average amount of time spent off the road for 34 different car brands. And find the most and least reliable car brand in 2020.
In our annual Which? Car Survey, we surveyed more than 47,000 motorists about their cars, what problems they've had and if they've broken down so we can provide reliability ratings for hundreds of cars.
0-3 years reliability rating
3-8 years reliability rating
The most reliable car brand received a full five-star score for cars aged three years and under, and also for cars that are three to eight years old. Only two other brands managed this rating for both age groups.
A five-star score means that in the few instances the brand's cars did go wrong, they were typically fixed in less than a quarter of a day. This helps to cement our top brand's position as the most dependable car brand there is.
Its compact SUV was its most reliable model. During the first three years of its life, this reliable car had one of the lowest fault rates of the hundreds of cars we collected information from in our survey.
One of the most recognisable car brands in the UK is also one of the least reliable - around half of owners reported issues with their car in the year before our survey.
It was also the only manufacturer to get the the lowest mark possible (one star) for both its new and old cars.
There were lots of common issues found amongst the least reliable cars, including problems concerning the exhaust/emission system, faulty software and the sat nav.
Faults are weighted according to seriousness. So the more severe the fault and the more time the car is off the road, the harder the model will be hit in our results.
The scores for each of these areas are then combined to provide an overall reliability score for each manufacturer, which is represented by a star rating, with one star being the poorest and five the best.
Our robust reliability research is powered by the experiences of 47,013 owners, who have given detailed insight into the ownership and maintenance of 55,833 individual cars (online survey: Dec 2019 to Feb 2020).