MOT advisory: tyre tread worn close to the legal limit
This is the most common advisory in this pilot, noted on roughly one MOT in six. The tester measured the tread and found it legal on the day, but only just, or found one edge wearing faster than the rest. It's a reminder, not a fail, and the car passed.
What the tester wrote
| Result | Wording on the certificate | Category |
|---|---|---|
| Advisory | Tread depth: worn close to legal limit/worn on edge | Advisory (pass) |
| Fail | Tread depth: tread depth below requirements of 1.6mm | Dangerous |
What the MOT checks
The tester checks the main grooves across the middle three-quarters of the tyre and all the way round. Below 1.6mm it's a fail. Above that, but close, they can write this advisory.
Watch for the words 'worn on edge'. They matter more than the depth. A tyre wearing on its inner or outer shoulder usually points to alignment that's out, worn suspension parts or tyres run at the wrong pressure.
"The primary grooves of the tread pattern must be at least 1.6mm deep within the central three-quarters of the breadth of tread and around the entire outer circumference of the tyre."
MOT inspection manual, section 5.2.3 Tyres. Read it on GOV.UK
How common it is
In 2025 this advisory was recorded on 15.8 in every 100 class 4 MOT tests (5,235,190 of 33,210,774 initial tests). The matching fail was recorded on 2.2 in every 100 (729,873 tests).
The typical car with the advisory was 10 years old with 79,148 miles recorded (medians).
| Age at test (years) | Advisory per 100 tests | Fail per 100 tests |
|---|---|---|
| 0-2 | 12.1 | 1.1 |
| 3 | 12.1 | 1.2 |
| 4-5 | 13.4 | 1.5 |
| 6-7 | 14.6 | 1.9 |
| 8-10 | 16.2 | 2.3 |
| 11-14 | 18.3 | 2.8 |
| 15-19 | 18.2 | 2.8 |
| 20+ | 12.5 | 1.8 |
'Not shown' means fewer than 1,000 tests in that cell, or a cell hidden so a small one can't be worked out. Age is years since first registration. First MOTs often happen just before a car's third birthday, so many show as age 2.
Does it turn into a fail at the next MOT?
We followed the same cars to their next MOT, 240 to 500 days later (4,502,088 pairs where this advisory was recorded). 4.6% failed on the same item at that next test, and another 21.8% had the same advisory again.
Among cars where this item wasn't noted at all, 1.78% failed on it next time. So a car with this advisory was about 3 times as likely to fail on this item as one without it, though the chance is still small.
These are averages. We can't see what owners did between tests. Some will have fixed the problem, and a fix would stop a fail.
What it usually means for a buyer
On its own this is normal wear. Tyres wear out, and a car with this note just needs tyres sooner than one without it. If the seller hasn't changed them since the test, budget for a pair.
If the note says the tyre is worn on its edge, look at the other advisories on the same certificate. Edge wear next to a worn suspension bush or track rod end tells you more than either note on its own.
Typical fix
Replace the tyres, normally in pairs on the same axle. If the wear was on one edge, ask for a four-wheel alignment check at the same time so the new tyres don't go the same way. Prices vary a lot by car and garage, so get a quote for the specific car.
Questions to ask the seller
You can read any car's MOT history, including advisories, free on GOV.UK. Our MOT advisory decoder explains the other notes in plain English.
Related MOT advisories
- Track rod end ball joint has slight play
- Tyre slightly damaged, cracking or perishing
- All MOT defects
- Buying a used car: a step-by-step guide
Sources and limitations
- Data: DVSA MOT anonymised test results and test items, class 4 initial tests, 2024 and 2025 (open data on GOV.UK). Same DVSA data as our MOT dataset.
- 'Fail' includes items fixed at the test centre within an hour (pass after rectification).
- An advisory is a tester's judgement on the day. Testers differ, and some problems are not visible at an MOT.
- The MOT is not a service and does not check the engine, clutch or gearbox in depth.
- Counts under 1,000 are not shown. No make or model figures are published here.
Contains public sector information licensed under the Open Government Licence v3.0. Source: Driver and Vehicle Standards Agency (DVSA), MOT Anonymised Data. Analysis by CarCheckHQ. Not endorsed by DVSA.
Written by the CarCheckHQ team.