When to change your tyres
Your tyres are the only part of the car that touches the road, so keeping them in good order matters for you, your passengers and everyone around you. Here is how to tell when it is time to replace them.
Why it matters, and what the law says
Tyres with enough tread and the right pressure grip the road safely. Tyres without them can be the difference between a safe car and one likely to cause an accident.
It is also illegal to drive on tyres with too little tread or the wrong inflation. You can be fined and receive penalty points for each illegal tyre, and if all four are below the limit you could risk losing your licence.
The legal minimum tread depth is 1.6 mm. Do not wait until you reach it.
Check the tread
The grooves in the tread push water away from the tyre so it can grip. As they wear shallow, the risk of aquaplaning and longer braking distances goes up.
Most tyres have tread wear indicators, small bars level with the legal minimum of 1.6 mm. You can also try the 20p test: put a 20p coin in the main grooves, all around each tyre. If you can see the coin’s outer band, the tyre may be at or near the limit. Wet grip drops as tread wears, so many drivers replace before the limit, for example at around 3 mm.
Check the pressure
Pressure affects both wear and handling. Find the right figures in your owner’s manual or on the fuel filler flap, and use the same units (bar or PSI) for every tyre. Our guide to how often to check tyre pressure shows how.
Can tyres be out of date?
Tyres are usually safe for up to around ten years after production. Once they are six or seven years old, keep a closer eye on them. The age is printed on the sidewall as a date code. See how to read your tyre sidewall.
Age counts even if the tyre has barely been used. Tyres left standing for a long time can dry out and split as the weather changes.
What else to look for
- Chunks missing from impacts.
- Sharp objects embedded in the rubber.
- Uneven wear. Often a sign of pressure or alignment problems.
- Cracks, blisters or bulges in the sidewall.
- The spare. Check it too.
Speed, load and driving style all affect wear, as do potholes and kerbs, which can knock your wheels out of alignment. See 10 signs you need a wheel alignment.
Can a puncture be repaired?
A puncture near the sidewall cannot be repaired, and the tyre must be replaced. A puncture in the middle of the tread can sometimes be repaired, but a roadside fix is only temporary: have a tyre specialist look at it. The full extent of the damage can only be judged properly with the tyre off the wheel.
Seasons and run flats
A tyre in good condition may still be wrong for the season. When temperatures fall in autumn, summer tyres can stop gripping well. All season tyres avoid the swap, and winter tyres suit the coldest roads. Read about summer tyres too.
Run flat tyres resist blowouts but still need regular checks, and in most cases they must be replaced rather than repaired. See what run flat tyres are.