What the new figures show
DVSA updated its MOT testing data for Great Britain on 10 September 2026. The new figures move tyres above brakes in the table of car failures.
The release covers the 2025 to 2026 financial year.
DVSA's table puts tyres at fault on 6.23% of all tests. Brakes came just behind at 6.10%.
A year earlier the order was the other way round, with brakes on 6.63% and tyres on 6.39%.
Tyres didn't get worse, brakes got better
It would be easy to read that swap as tyres getting worse. They didn't.
Both categories improved. Tyre faults fell from 6.39% to 6.23% of tests, and brake faults fell from 6.63% to 6.10%.
Brakes simply improved faster, and that's what moved them below tyres.
Nothing in the data explains why, and DVSA doesn't offer a reason. So treat the crossover as a change in the rankings rather than a warning about tyres specifically.
Lighting is still the most common failure by far
Neither tyres nor brakes are near the top. In DVSA's table, lighting and electrical faults were found on 10.44% of tests, and suspension on 8.90%.
Both sit comfortably above the tyre figure.
The full order for 2025 to 2026 runs lighting, suspension, tyres, brakes, then visibility on 4.28%.
Overall, 27.51% of cars failed first time, across 33.3 million tests. That's a bit more than one car in four, and the lowest rate in the published series.
Which failures meant the car was dangerous
Frequency isn't the same as risk. This is where the two part company.
When a tester records a dangerous defect, it means the car shouldn't be driven away as it is. Tyres accounted for 60.60% of every dangerous defect found in 2025 to 2026.
Brakes came second on 28.80%. Between them that's nearly nine in ten.
Lighting tells the opposite story. It fails more cars than anything else, yet it made up just 1.27% of dangerous defects.
Suspension was 5.32%.
Put another way, a dangerous tyre turned up on 4.47% of all MOTs. Roughly one test in twenty-two found a car that shouldn't have been on the road on the tyres it arrived on.
What to check before your test
Tyres are the cheapest thing on this list to check yourself. That's what makes the dangerous share so striking.
The MOT inspection manual requires at least 1.6mm of tread. That applies across the central three-quarters of the tread and around the whole circumference of the tyre.
Look for cracking, bulges and uneven wear while you're down there.
Uneven wear often points at something else, and our guide to what fails cars at MOT covers the rest of the categories in full. This piece is part of our guide to MOT, road tax and staying legal.
Common questions
Are tyres now the most common MOT failure?
No. Lighting and electrical faults remain the most common by a wide margin, on 10.44% of tests. Suspension sits second. Tyres moved into third on 6.23%, ahead of brakes on 6.10%.
Why did tyres move above brakes?
Because brake faults fell faster, not because tyre faults rose. Both improved on the year. DVSA publishes no explanation for the change, so anything beyond that is guesswork.
What counts as a dangerous defect?
It's the most serious grade a tester can record, and it means the car shouldn't be driven until it's fixed. Tyres made up 60.60% of them in 2025 to 2026, and brakes 28.80%.
What is the legal tyre tread depth?
1.6mm, measured across the central three-quarters of the tread and around the whole circumference. Below that the car fails, and so does a tyre with a bulge, or a cut deep enough to reach the cords.