Sub-standard tread depth increases the risk of having an accident, and could result in a £2,500 fine for each tyre that does not meet legal minimum.

Your tyres connect your vehicle to the road, and need to be kept in good condition to maximise grip and minimise stopping distances.

The condition of your tyres could be the difference between having an accident - and not.

And if you're fined for having a set of four worn tyres, you could be £10,000 out of pocket.


The 1.6mm minimum tread depth

Across the UK and the EU, the minimum legal tread depth is 1.6mm across the central three-quarters of the tyre. This minimum applies to the entire circumference.


But aim for 3mm+ tread depth

However, experts have warned that 1.6mm is not sufficient to ensure road safety. According to a report by the Road Safety Observatory, conducted by engineering firm MIRA, "The risk of being involved in a collision remained constant until vehicle tread depths dropped below 3mm".

When a tyre tread gets worn below 3mm, stopping distances increase, making it harder to avoid collisions.

Worn tyres increase the chance of being in an accident that results in injury or even death. As the Road Safety Observatory report states:

"In  2016, 8 people were killed, 150 seriously  injured  and ... 876 [suffered] road casualties in  total in reported road accidents in Great Britain in which illegal, defective or under inflated tyres  were recorded as a contributory factor by the police officers investigating the scene."


Tyres help shift water away from your tyres

Did you know your tyres can disperse up to a gallon of water in heavy rain? This ability is the culmination of decades of product research, and reduces the chance of aquaplaning and losing grip on the road.


The 20p tyre tread depth test

This is one of the quickest and easiest ways to check your tyre tread depth.

Simply place a 20p coin in the groove of your tyre. If the outer band of the coin cannot be seen, your tyres meet the minimum legal tread depth. Be sure to carry out this test all around the tyre to ensure there are no bald patches.

In truth, most drivers seldom check their tyre tread depth. Indeed, a 2019 KwikFit survey of 2,000 UK drivers found just 25% even knew the minimum legal tread depth.

Ideally, drivers should do the 20p check every two weeks - and before undertaking long journeys.


Tyre tread depth gauge

You can purchase a special tyre tread depth gauge - although a 20p coin does the job just as well.


Use tread wear indicators

Your tyres may have tread wear indicators. These are elevated strips of rubber across your tyre's longitudinal grooves. When the surrounding tyre rubber - the grips - wear down to the same level as the indicator, it's time to replace your tyres.

Reasons to ensure your tyres have a tread depth of at least 1.6mm
  • Poor condition tyres could contribute to you having an accident, potentially resulting in you, your passengers or other road users getting injured or even being killed.
  • If your insurer finds your tyres were below the legal limit following an accident, they may have grounds not to pay out - i.e., bald tyres could invalidate your insurance.
  • The fine for driving on a set of four tyres with a tread depth of under 1.6mm would be £10,000.


Increased risk of blowouts

Bald tyres suggest the general condition of your tyres may be poor, and could lead to other issues - such as punctures or even blow-outs.

“The condition of a vehicle’s tyres is an important safety factor: tyres with insufficient tread depth may affect stopping distances and grip on the road. Incorrect tyre pressures can affect braking and steering and may cause premature tyre failure. Damaged tyres are more likely to suffer punctures or blow-outs.”