"Tyre worn close to legal limit": what the MOT advisory means
"Tyre worn close to legal limit" means the tyre passed, but the tread is getting near the 1.6mm minimum. It's legal today. Plan to replace it within the next few weeks rather than waiting for the next MOT, because a tyre at this stage won't last another year of normal driving, and grip in the wet is already noticeably worse than on a new one.
What the legal limit actually is
UK law, and the MOT, need at least 1.6mm of tread across the central three-quarters of the tyre's width, all the way round. The outer edges can be lower without making the tyre illegal, which is why a tyre can look fine from the side and still be close to the limit in the middle.
There's no fixed depth at which testers give this advisory. They give it when they think the tyre is getting near the line. In practice that often means somewhere a little above 2mm.
A new car tyre usually starts with around 8mm of tread. So "close to legal limit" means most of the useful life has gone.
Can you still drive on it?
Yes. The tyre is legal and the car passed. But there are two good reasons not to leave it long.
First, wet grip. Stopping distances on wet roads get noticeably longer as tread wears down, and the drop is steepest in the last couple of millimetres. That's why many in the tyre industry suggest replacing at around 3mm rather than waiting for 1.6mm.
Second, the law doesn't care when your MOT was. Get stopped on a tyre under 1.6mm and you can be fined up to £2,500 and given 3 penalty points, for each illegal tyre.
How to check the tread yourself
- Tread wear indicators. Look in the main grooves for small raised bars of rubber. They sit at 1.6mm. If the tread is level with them, the tyre is at the limit.
- A tread depth gauge. A few pounds from any motor factor and far more accurate than a coin. Measure in at least three places across the tyre and at a few points round it.
- The 20p test. Put a 20p coin into the main groove. If you can see the outer band of the coin, the tread is low and you should measure it properly.
Check the inner edge too. On a lot of cars it wears first, and you can't see it without turning the steering to full lock or looking from underneath.
"Worn close to legal limit/worn on edge"
You'll often see this full wording. The "worn on edge" part matters more than people think. A tyre that's worn on one edge has usually been running with the wheel alignment (tracking) out, often after a kerb or a pothole. Worn suspension bushes can do the same.
Replace the tyre without fixing the cause and the new one will wear the same way. A tracking check costs roughly £40 to £80 at most tyre shops. Get it done when the new tyres go on. When the alignment won't adjust properly, the garage may find worn suspension parts, which we cover in the guide to suspension bush advisories.
What a replacement costs
Prices depend on tyre size more than anything. As a rough guide for a typical family car, fitted:
| Tyre type | Rough price per tyre, fitted |
|---|---|
| Budget | £60 to £80 |
| Mid-range | £75 to £110 |
| Premium | £100 to £160 |
Bigger wheels and performance sizes cost more. Prices move with the market, so treat these as a guide and get a quote for your size.
Replace in pairs on the same axle if the other tyre is also getting low, so grip is even side to side. Buying just two? Tyre makers generally recommend the newer pair go on the rear, because losing grip at the back is harder to control.
What to do now
When this is the only advisory on your MOT, it's a simple job: get a price for your tyre size and book it in. With others on the list, paste the whole result into the MOT advisory decoder to see everything in order of urgency.
Also look at the sidewalls while you're down there. If the advisory mentioned cracking or perishing as well, read what tyre cracking on an MOT means.
Got more than one advisory?
Paste your whole MOT result into the decoder. It explains every line, sorts them by urgency and adds up a rough repair budget.
Decode my MOT