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MOT guide · latest DVSA data

What fails an MOT?

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.

27.3%of car MOTs failed in 2025
10.2%failed on lights and electrics
7.3%had a dangerous defect
By area

How often each part of the MOT fails

Share of all car MOTs in 2025 that failed on each area of the test. One MOT can fail on several.

Suspension1 in 11 MOTs
Tyres1 in 16 MOTs
Brakes1 in 17 MOTs
Body, structure and exhaust1 in 33 MOTs
Steering1 in 54 MOTs
Seat belts and airbags1 in 110 MOTs
Wheels1 in 260 MOTs
Number plates and VIN1 in 320 MOTs

The individual parts that fail most: most common MOT failures.

How defects are graded

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.

What's tested

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.

Questions

What fails an MOT?

Any defect the tester rates major or dangerous. Minor defects and advisories are recorded but the car still passes.

What fails an MOT most often?

Lights and electrics: 10.2% of car MOTs in 2025 failed on them, then suspension (8.8%), tyres (6.3%) and brakes (6.0%).

Does the MOT check the engine, clutch or gearbox?

No. GOV.UK says the test doesn't cover their condition. Emissions are tested, and the engine warning light is checked.

How many cars fail their MOT?

27.3% of car MOTs in 2025, counting cars fixed within the hour as fails, as DVSA does.

More about the MOT

Is it an MOT failure?