UK Tyre Tread Depth Law: When Should You Replace Your Tyres?

The legal minimum

In the UK, car tyres must have at least 1.6mm of tread across the central three-quarters of the tyre, around the entire circumference. Driving on tyres below that can mean a fine of up to £2,500 and three penalty points for each illegal tyre — so four worn tyres could put 12 points on your licence. Worn tyres are also one of the most common reasons for failing an MOT.

Legal is not the same as safe

Tyre grip on wet roads drops noticeably as tread wears, and stopping distances get longer long before you reach 1.6mm. Many tyre and motoring organisations recommend replacing tyres at around 3mm, especially going into autumn and winter when roads are wet for months at a time.

How to check your tread

The 20p test: put a 20p coin into the main tread grooves. If you can see the outer band of the coin, the tread may be close to or below the legal limit — get it checked. Try several points around each tyre, as tyres do not always wear evenly.

Tread wear indicators: most tyres have small raised bars in the bottom of the main grooves. When the tread is level with them, the tyre is at 1.6mm and must be replaced.

While you are down there, look for cuts, bulges in the sidewall and anything stuck in the tread. A bulge means internal damage and the tyre should be replaced.

Uneven wear is a warning sign

If one edge of a tyre is wearing faster than the rest, the wheel alignment is probably out — often after clipping a kerb or a pothole. Wear in the centre can point to over-inflation, and wear on both edges to under-inflation. Fixing the cause stops your new tyres wearing out early too.

Get them checked

We can check your tread depth, tyre condition and pressures, and look at the wear pattern to see if the alignment needs attention. Call us on 0121 476 2287 or call in to us on Bristol Road South, Northfield.