MOT Advisories Explained: Spot a Shady MOT History

What is an MOT advisory?

So if you're looking at a used car and its MOT history is dotted with advisories, don't panic and don't walk away on that alone. But don't ignore them either. Advisories are free information about how the car has been treated, and when you're buying someone else's car, that's exactly the sort of thing you want to read carefully. This guide explains what an advisory actually is, what gov.uk's free MOT history check shows you, and — the bit most guides skip — how to read a run of advisories across several years like a buyer instead of a mechanic.

An advisory is the tester's way of saying "this is fine today, but keep an eye on it." In the official MOT inspection manual, the wording is that where an item "is not sufficiently deteriorated to justify rejection, there may be an option to select 'advisory' to inform the presenter of this fact."

The classic example is tyre tread. The legal minimum is 1.6mm. A tyre sitting at 2mm still passes, but a tester will often flag it as an advisory because it's clearly going to need replacing before long. Same idea with a bit of surface corrosion near — but not on — a structural area, or brake pads that are wearing thin without being dangerous yet.

Crucially, an advisory is not one of the defect categories the MOT uses to pass or fail a car. It sits outside them.

Advisory vs fail — the difference that actually matters

Since 20 May 2018, MOT defects have been sorted into three severity categories. This matters because older records — anything before that date — may read differently, so bear the date in mind when you're scrolling back through a long history.

Dangerous and major defects (these fail the car)

• Dangerous defects are, in gov.uk's words, "a direct and immediate risk to road safety or having an impact on the environment." The car fails, and you shouldn't drive it away.
• Major defects "may prejudice the safety of the vehicle, have an impact on the environment, put other road users at risk." These also fail the car until they're fixed and it's retested.

Minor defects (a pass, but recorded)

A minor defect has "no significant effect on the safety of the vehicle or impact on the environment." The car passes and gets its certificate, but the fault is written onto the record. It's the tester telling you to sort something out even though it wasn't a fail.

Advisories (a pass, and an early warning)

Advisories sit below even minor defects. They don't appear as a failure reason and they don't stop the car passing. Think of them as the informal early-warning layer: not a defect category at all, just a heads-up that a part is on its way out.

How to check a car's full MOT history before you buy

You don't need to pay anyone for the basic MOT record — our free car check gives it to you from just the number plate, alongside the car's tax status. For each test on file it shows:

• the test date
• the pass or fail result
• the mileage recorded at that test
• the reasons for any failure
• any advisory notices the tester recorded

Reading those together across several years is where the value is, especially the mileage at each test — that's your first line of defence against a clocked car, because the recorded figures should only ever climb.

Two limits to know. First, the service shows MOT records only — it does not show a car's service or maintenance history, so a clean MOT record isn't the same as a full-service record. Second, coverage goes back to 2005 for cars, motorcycles and vans in England, Scotland and Wales, and to 2017 in Northern Ireland. Older than that and the trail simply isn't there.

You can run the same lookup — plus the DVLA tax and SORN status — through our free MOT check tool if you'd rather have it in one place while you're comparing cars.

Common MOT advisories — and what they can mean

These are the advisories you'll see most often. This isn't an official DVSA ranking, just the ones testers and garages commonly flag:

• Tyres — tread getting close to the 1.6mm limit, uneven wear, perishing or minor damage.
• Brakes — pads or discs wearing thin, or the beginnings of an imbalance.
• Corrosion — surface rust near (but not yet on) a structural or braking component.
• Suspension — worn bushes, or play starting to develop in a joint.
• Lighting — a dim or misaligned lamp, or a lens starting to fade.
• Wiper blades — split or smearing, flagged for visibility.

On their own, most of these are ordinary wear-and-tear on any used car, and a cheap fix. A single "tyre worn close to legal limit" advisory tells you almost nothing bad about a car. It's the pattern, not the individual line, that's worth reading.

Red flags: reading an MOT history like a buyer, not a mechanic

Here's the part the upsell-a-repair garage blogs don't cover. When you look at several years of history together, some patterns are worth pausing on:

• The same advisory, year after year, never fixed. A "brake pads wearing thin" note that reappears at three consecutive tests suggests an owner who does the bare minimum to scrape a pass. Mechanics and experienced buyers generally read recurring, un-actioned advisories as a sign of deferred maintenance rather than isolated bad luck — treat it as a prompt to look harder, not a diagnosis.
• A cluster of related advisories in one test. Corrosion plus worn suspension plus tired brakes, all in the same year, points to a car that's been run hard or maintained on the cheap. Not necessarily unsafe today — but a fair negotiating point and a good reason to pay for an independent inspection.
• Mileage that doesn't add up. The recorded mileage should rise steadily test to test. A figure that drops, or barely moves for a year and then leaps, is a clocking red flag worth investigating before anything else.
• Gaps in the test history. A missing year (beyond a legitimate SORN period) raises the question of where the car was and why it wasn't tested.
• A suspiciously clean pass straight after a long advisory list. If last year's test had six advisories and this year's is spotless, ask what was actually done — and for the receipts. Genuine repairs come with invoices.

What an MOT history check can't tell you

Be honest with yourself about the limits of the free record.

It doesn't cover general servicing — oil changes, cambelts, clutches, gearbox health — beyond the safety and emissions items the MOT actually tests. A car can have a flawless MOT history and a neglected engine.

And a pass — even a clean one — is a point-in-time check, not a guarantee. It says the car met the standard on the day it was tested, nothing more. The Highway Code is clear that keeping a vehicle roadworthy is the driver's ongoing responsibility, and it advises investigating a developing fault straight away rather than waiting for the next MOT.

There's a further catch worth knowing: the record is only ever as reliable as the tester who signed it off. The DVSA does police this — from 9 January 2026, under MOT Special Notice 05-25 (published 19 December 2025), a tester or authorised examiner principal given a two-year or five-year disciplinary "cessation" cannot hold any MOT role for the whole of that period.

Tighter enforcement is a good thing. But it's also a reminder that the person who stamped a historic test wasn't infallible, and a small number aren't honest. A clean MOT history is reassuring — it isn't a cast-iron guarantee.

That's the case for going a step further before you hand over money. The MOT record won't show you a car's write-off or finance history, or verify mileage against a fuller data set — for that, a Comprehensive check pulls the wider vehicle history together so the MOT record isn't the only thing standing between you and an expensive mistake.

Check before you buy

Before you view a car, spend two minutes on its MOT record — it's free, it's official, and it often tells you more than the seller will. Run the plate through our MOT check tool, read the advisories as a pattern, and let what you find shape the questions you ask and the price you pay.

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