What is the law relating to tyre tread depth?

Tyre care information from Michelin

The minimum legal tyre tread depth in Europe for cars and light vans is 1.6mm across the central three-quarters of the tread width and around its entire circumference.

Checking your tyre tread depths
Check the depth of the main tread grooves in several places across and around the tyre, using a tread depth gauge as instructed by its manufacturer. If the tread depth is 1.6mm or less, the tyres need to be replaced immediately.

Tyre tread depth can also be checked using tread wear indicators which are moulded into the base of the main grooves. When the tread surface is worn to the same level as these indicators, the tyre is at or below the legal limit and should be replaced immediately.

If you are not confident about checking your tyre tread depths yourself, or if your tread depths are approaching the legal limit of 1.6mm, have them checked professionally by a tyre specialist.

Why are tyre tread depths important?
The tyre is the only part of the vehicle that grips the road, and so your tyres tread depth is very important for safety. Tread grooves drain water from the tyre’s area of contact with the road, so driving with low tread depth increases the risk of aquaplaning. Low tread depth also increases the likelihood of tyre damage, and can reduce grip in winter weather conditions.

Motorists driving on tyres whose tread depths are below the legal limit also risk a fine penalty points on their licence for each illegal tyre.