How to read a used car's MOT history like a mechanic
A five-minute MOT history check tells you more about a used car than the dealer will. Here's what to look for, what's a dealbreaker, and what's fine.
Published
Why the MOT history is the single best pre-purchase check
Every MOT test since 2005 is logged on a free government database. That means for any UK car over three years old, you have a timestamped, tamper-resistant record of failures, advisories, mileage at each test, and the testing station — which adds up to a better picture than any 'one previous owner, FSH' description on a listing.
What to actually look for
Three signals tell you most of what you need to know.
- Mileage consistency: the recorded mileage at each MOT should rise smoothly. A drop, or an implausibly low annual figure compared to neighbours, is a clocking red flag.
- Repeated advisories: a brake pad advisory that stays on the record for two consecutive MOTs means it was never addressed. Same for corrosion — 'corrosion but not excessive to a structural component' becomes 'corrosion' the next year.
- Failure categories: a single failure on bulbs or tyres is ordinary. Repeated fails on suspension, brakes, structure or emissions suggest a car that's been run on the edge of legal.
What is fine
Plenty of advisories are noise. A 'tyre worn close to legal limit' on the first test of a year that the dealer has already replaced? Resolved. A five-year-old car with one emissions fail on a first attempt, followed by a pass? Usually just a hot engine or a sensor; nothing to avoid over.
Dealbreakers
A structural corrosion failure that's never shown a subsequent clean pass on the same component. A mileage break that the dealer can't explain with a swapped instrument cluster and paperwork. A year with no MOT at all on a car that wasn't SORN'd — that car was driven illegally and probably not maintained.
The takeaway
Before you book a viewing, paste the VRM into WheelsAI's free MOT check. Ninety seconds of reading the history gives you the strongest leverage you'll ever have on price — you already know what the dealer is hoping you don't.
Frequently asked questions
Frequently asked questions
Does an MOT history check cost anything?
No. DVSA publishes MOT history free to the public. WheelsAI wraps the same data with context and plain-English explanations.
Can a dealer hide an MOT failure?
No. Once a test is logged, it stays. Retesting at a different station does not erase the original failure.
What about cars under three years old?
They have no MOT yet. Lean on the service book, warranty records and a manufacturer VIN check instead.