By the H Auto Mobile Tyres team · Updated 1 November 2026
The legal minimum is 1.6mm
In the UK, car tyres must have at least 1.6 mm of tread across the central three-quarters of the tread, all the way around the tyre. Driving on tyres below this is illegal and unsafe.
The penalties
Each illegal tyre can mean a fine of up to £2,500 and 3 penalty points on your licence. With four worn tyres, that adds up fast. Worn tyres are also a common reason for failing an MOT.
Check it with a 20p coin
- Put a 20p coin into the main grooves of the tyre.
- If you can see the outer band of the coin, the tread may be close to or below the legal limit.
- Check in a few places around each tyre, and on the inside edge too, as tyres can wear unevenly.
- Many tyres also have small tread wear indicators in the grooves. When the tread is level with them, the tyre needs replacing.
Why replace before 1.6mm?
Grip in the wet drops noticeably as tread wears down, so stopping distances get longer well before the legal limit. Many drivers replace their tyres at around 3 mm for this reason.
Uneven wear is a warning sign
If one edge of a tyre is wearing faster than the rest, your wheels may be out of alignment or your tyre pressures may be wrong. It's worth getting it checked when you replace the tyres.
New tyres fitted where you are
We fit new tyres at your home, your work or the roadside, so you don't need to visit a tyre shop. Call or WhatsApp 0330 043 6598 with your tyre size and location. See mobile tyre fitting.
