UK law insists your car must be fitted with the correct tyre for the vehicle you own - and that they are inflated to the manufacturer's recommended pressures. The tread depth must be a minimum of 1.6mm across 75% of the tyre.
The worse your tyres are, the more at risk you could be from them failing you at a crucial moment and either causing or contributing to an accident. Obviously we desperately want to help you avoid this situation, but we also want to save you money and points on your licence too. Remember - for each illegal tyre you're discovered to have you could be fined up to £2,500 and have up to 3 penalty points put on your licence. Your insurance is also invalid if you have an accident when driving on illegal tyres.