Any defect the tester rates major or dangerous. In 2025, 27% of car MOTs failed, most often on lights and electrics, suspension, tyres and brakes.
Share of all car MOTs in 2025 that failed on each area of the test. One MOT can fail on several.
The individual parts that fail most: most common MOT failures.
The MOT inspection manual puts every defect in one of three groups:
Testers can also give an advisory for something that isn't bad enough to fail yet. A car with only minor defects or advisories passes.
GOV.UK lists these parts of a car as checked at the MOT:
In GOV.UK's words, the MOT "isn't the same as having your vehicle serviced" and doesn't cover the condition of the engine, clutch or gearbox.
Any defect the tester rates major or dangerous. Minor defects and advisories are recorded but the car still passes.
Lights and electrics: 10.2% of car MOTs in 2025 failed on them, then suspension (8.8%), tyres (6.3%) and brakes (6.0%).
No. GOV.UK says the test doesn't cover their condition. Emissions are tested, and the engine warning light is checked.
27.3% of car MOTs in 2025, counting cars fixed within the hour as fails, as DVSA does.