Ideally, tyre tread depth should be checked at least once a month at the same time that you check your tyre pressure.

If you do not have a calibrated tread depth gauge a 20p coin provides a useful guide.

1. Insert the 20p coin into the main tyre grooves at several places around the circumference of the tyre and across its width.
2. If the outer band of the 20p coin is visible whenever you check the tread, your tread depth may be illegal and you should have them checked by a qualified tyre specialist.
3. When checking your tread depth, give the rest of the tyres a visual inspection for any cuts or bulges and remove any stones or objects embedded in the tread.