Everything UK drivers need to know about the MOT — preparation checklists, common failures, advisories, retests, and diesel emissions.
Check any UK car before you buy — free.
What the MOT smoke test measures on a diesel, the limits by age, the DPF rules and fines on GOV.UK, and why short cold trips in winter are the pattern to watch.
Which suspension parts get noted as MOT advisories and how the share rises with car age: worn bushes, corroded springs and leaking shock absorbers.
Which cars first used 2012-2015 most often failed the MOT with a steering item in 2021-2025, with the national figure, the test counts and what to check first.
Cars first used 2008 to 2011 ranked by the share of MOT tests failing with a lighting or electrical item, beside the national figure, every base shown.
Cars first used 2008 to 2011 ranked by the share of MOT tests that failed with a suspension item, with the national figure and every base shown.
Brake pad advisories are recorded at much the same rate at every car age, but corroded brake pipes rise from 0.1% to 11.5% of tests. What each brake note means.
Nearly 1 in 5 MOT tests on cars aged 10-14 record a tread-depth advisory. How tyre tread, tear, cut and bulge notes change with age, and the winter check.
The MOT fail items that appear once a car passes 15: corroded brake pipes and mountings, exhaust leaks, lamp faults and headlamp aim, and what to check.
From 14 October 2026 MOT testers accept approved LED replacement bulbs in halogen headlamps if the approval sticker is present. What the DVSA notice says.
Which cars first used 2012-2015 most often failed an MOT with a suspension item, ranked by share of tests against the national 6.0%, with every base shown.
The MOT fail items that appear between six and nine years old: broken coil springs and dead bulbs join tyres, pads and wipers, with a buyer's checklist.
MOT tests on cars aged 10 to 14, 2021-2025: about 7 in 10 pass at ten, under 3 in 5 at fourteen. The eight faults recorded most and what to check before buying.
Which cars first used 2012-2015 most often failed the MOT with a lighting or electrical item: the highest shares against the 6.8% figure for all models.
What a minor defect means on an MOT, and the items recorded most by car age: one number plate bulb out on about 1 in 18 tests on cars aged 15 and over.
Does a chipped windscreen fail the MOT? The 10mm and 40mm rule, and how often damage is logged as minor, about 1 in 37 tests on cars aged 10-14, or fails.
What fails a car at its first MOT at three years old, from the 1 in 45 wiper fail to tyres and pads, how it differs from a ten-year-old, and the checks to do.
The national MOT pass rate rose from 70.5% in 2021 to 72.3% in 2025. At a fixed age the rise is larger: ten-year-olds went from 65.8% to 71.9%. What it shows.
How often seat belts and the airbag warning light fail the MOT at each car age, from 1 in 800 tests on young cars to 1 in 85 past fifteen, and what to check.
Brake items fail 1.6% of first tests on cars first used in 2021 and 6.6% on 2006 cars. Which items fail at each age, and what to check before a wet week.
Emissions items fail 0.4% of first tests on cars first used in 2021 and 3.5% on 2008 cars. The item recorded most at every age is the engine warning light.
About 7 in 8 cars pass at age three (87.8%), about 5 in 9 at seventeen (56.0%). Where the curve falls fastest, why it levels off, and how to use it when buying.
Position lamps, stop lamps and headlamp aim lead MOT light fails, rising from 2.4% to 11.0% of tests with age. What to check before 25 October.
The MOT pass rate was 70.0% in January and 72.6% in September, but most of the gap is the age of cars tested each month. The figures by age band.
Suspension fails climb from 0.7% of first tests on 2021 cars to 9.4% on 2009 cars; coil springs lead at every age. What fails and what to check.
Between 3.2% and 4.9% of first tests fail on tyres at every car age, yet tyres are over half of fails on new cars. Why, and the winter tread check.
Every class 4 MOT carried out in Great Britain is recorded by the DVSA, and the anonymised results are published as open data. SortedCars works from that record: tens of millions of first tests a year, with every failed item, every minor defect and the odometer reading at each test. The articles in this section turn that record into answers an ordinary driver can use. Which items fail most often at each age. How the share of fails changes as a car gets older. Whether the month of the test makes any difference. What a pass after rectification means on a history.
Two habits run through all of them. Every figure is shown with the number of tests it rests on, because a percentage without its base is a guess dressed up. And every figure describes a population of cars, not any one car: a well-kept example of a model with a weak average can still pass, and a neglected example of a strong one can still fail. The numbers tell you where to look. They do not tell you what you will find.
Before any test, the quickest preparation is still to read last year's certificate. Our free car check shows the full MOT history for any UK registration, including the minor items and advisories that tend to become next year's fails, alongside the DVLA record. The guides below take one question at a time.
Check any UK car before you buy — free.