The most common reasons cars fail their MOT (2025 UK data)
One in four cars fails its first MOT. Here is exactly what they fail on, using the latest DVSA figures, and what each fault means if you are buying salvage.
MOT DATA · 6 min read
One in four cars fails first time
The latest DVSA figures put the initial MOT failure rate for cars and small vans at 27.24 percent, so more than a quarter fail on the first attempt, and the average failed car carries 2.42 separate defects. For a salvage buyer this is doubly useful: it tells you what tends to go wrong on any used car, and it tells you where a cheap MOT-failure buy is likely hiding its problems.
The full ranking, by share of cars tested
Here is what cars actually fail on, as a percentage of all tests. Lamps, reflectors and electrical equipment top the list at 10.36 percent. Suspension is next at 8.65 percent, then tyres at 6.23 percent, brakes at 6.10 percent, and visibility items like wipers, washers and glass at 4.65 percent. Body, chassis and structure account for 3.18 percent, noise, emissions and leaks 3.03 percent, and steering 1.84 percent. Everything else, including seat belts, road wheels and vehicle identification, sits under one percent each.
Cheap to fix versus expensive to fix
The top of that list is mostly good news for a flipper. Lights, wipers and many tyre or brake items are cheap consumables you can sort in an afternoon, which is why a car that fails only on those is often a bargain. The ones that hurt are suspension, body and structure, because corroded subframes, failed bushes and rot are labour heavy and can turn a cheap car into a money pit.
What is actually dangerous
DVSA also grades defects as dangerous. Tyres are the standout: they make up 60.32 percent of all dangerous defects found, even though they are only the third most common failure overall. Brakes are next at 29.08 percent of dangerous items. So on any salvage or MOT-failure car, tyres and brakes are the two things to check first, because they are both the most likely to be genuinely unsafe and among the cheapest to put right.
Reading a failure sheet before you buy
When a car is sold as an MOT failure, the failure sheet is a free inspection someone else paid for. A sheet full of lamps, wipers and a couple of tyres is a quick, cheap car. A sheet listing corrosion to a load-bearing area, or multiple suspension and steering items, is a warning. Run the car and the repair estimate through the Analyzer before you commit, so the failure list turns into a real number rather than a guess.