What Is the Legal Tyre Tread Depth in the UK?

The legal limit is 1.6mm

In the UK, car tyres must have at least 1.6mm of tread across the central three-quarters of the tyre, all the way around. Driving on tyres below that can mean a fine of up to £2,500 and three penalty points for each illegal tyre.

Tyres below the limit are also an MOT failure, and so are cuts, bulges and exposed cords.

How to check your tread with a 20p coin

Push a 20p coin into the main grooves of the tyre. If you can see the outer band of the coin, the tread may be getting close to the legal limit and you should have the tyres checked properly.

Check a few points around each tyre, across the middle and near both edges. Many tyres also have small tread wear bars in the grooves. When the tread is level with those bars, the tyre is at the limit.

Why 1.6mm is too low in practice

Tread clears water from under the tyre. As it wears down, the tyre grips less in the wet and the car takes longer to stop. The difference between a new tyre and a worn one on a wet road can be several car lengths.

For that reason, many drivers change tyres at around 3mm, especially heading into autumn and winter when the roads are wet more often.

Uneven wear means something else is wrong

If one edge of a tyre is wearing faster than the rest, the wheel alignment is usually out. A knock from a pothole or kerb is enough to do it. Wear in the centre or on both edges can point to the tyre pressures being wrong.

Fixing the alignment when you fit new tyres stops the new ones going the same way, and it can also cure a car that pulls to one side.

Tyres fitted in Smethwick

ER Automotive supplies and fits tyres, balances the wheels and checks the alignment. If you are not sure whether your tyres are legal, pop in to Cranford Street, call 0121 461 6097 or book online.