Tyres – Your legal obligations

If you ride with damaged or worn tyres you are in danger of being fined and in breach of your insurance policy.

General requirements

Every tyre fitted to a motorcycle, car or even a trailer or caravan must be fit for purpose and be free from defects which might damage the road or endanger an individual. This means the tyre:

  1. must be compatible with the other tyres fitted to the other wheel(s)
  2. must not have a lump, bulge or tear caused by separation or partial failure of the structure
  3. must not have a cut or tear in excess of 25mm or 10% of the width of the tyre and which is deep enough to reach the ply or cord
  4. must not have any part of the ply or cord exposed

Note: A vehicle is liable to fail an MOT if a tyre has any of the above faults or if the vehicle has tyres of different nominal size or aspect ratio on the same axle.

Duty to maintain

Each tyre must be correctly inflated to the vehicle manufacturer’s and the tyre manufacturer’s recommended pressure. (‘Run-flat’ tyres partially inflated or in flat condition are permitted in certain circumstances.)

Tread depth

Must not fall below the legal minimum. The tread is that part of the tyre in contact with the road in normal conditions. The minimum depth of tread depends on the class of vehicle.

Type of vehicle Minimum tread depth
Passenger vehicles (other than motorcycles) for not more than 8 seated passengers

Goods vehicles not exceeding 3,500kg max gross weight

Light trailers not exceeding 3,500kg max gross weight

At least 1.6mm throughout a continuous band in the centre 3/4 of the tread and around the entire circumference
Most vehicles larger than those listed above

Motorcycles 50cc and over with or without sidecar

At least 1.0mm throughout a continuous band across at least 3/4 of the breadth of the tread and around the entire circumference

NB: In the quarter where the tread may be less than 1.0mm, the original tread pattern must be visible

Mopeds and motorbikes under 50cc Original tread pattern must be visible


Where a vehicle fitted with an illegal or defective tyre is used on a road, a police officer may give the driver a fixed penalty notice.

A police officer has discretion not to issue a fixed penalty but to report the case for prosecution. In law, the driver and the owner (if different) are liable and one or both may be summonsed.

The maximum fine which a court can impose for using a vehicle with a defective tyre is £2,500 and three penalty points.

If a vehicle is fitted with more than one defective tyre, you can be summonsed for each tyre which is illegal. Disqualification is also possible in certain circumstances.