When Should You Replace Your Tyres? The Complete Guide

Most drivers wait until a tyre is visibly flat or completely bald before considering a replacement. But by that point, you've been driving on dangerous rubber for longer than you might think. There are several clear indicators that your tyres need replacing — and tread depth is just one of them.

The main signals are: tread depth below 3mm (we recommend replacing before the 1.6mm legal limit), tyres older than five to seven years regardless of appearance, visible bulges or cracks on the sidewall, persistent slow punctures, and uneven wear patterns that suggest a mechanical problem.

Rubber degrades over time even when a tyre isn't being used. The oils and chemicals in the rubber compound gradually dry out, leading to cracking and reduced flexibility. A tyre that looks fine on the outside may have significant internal degradation if it's more than five years old.

You can find the age of your tyre stamped on the sidewall as a four-digit DOT code. The first two digits are the week of manufacture and the last two are the year. A tyre stamped '2219' was made in the 22nd week of 2019. Most manufacturers recommend replacing tyres over ten years old as a maximum, and considering replacement from five years onwards.

A bulge in your tyre sidewall is a tyre failure waiting to happen. It indicates that the internal structure of the tyre — the cords that give it strength — have been damaged, usually by a sharp impact like a pothole. The outer rubber is all that's holding the tyre together at that point. This is an immediate replacement job — do not drive on a bulging tyre.

Cracks on the sidewall are a sign of rubber aging and UV degradation. Fine surface cracking on older tyres is common, but deep cracks that you can see into the tyre structure mean the tyre should be replaced. Run your finger along the sidewall — if you feel significant cracking, get the tyre inspected.

If you're in any doubt about the condition of your tyres, a professional inspection is always the best call. A mobile tyre fitter can come to your home or workplace and carry out a full assessment — checking tread depth with a proper gauge, inspecting sidewalls, checking for uneven wear, and verifying tyre age — all without you having to go anywhere.

Don't put off getting your tyres checked if you have any concerns. Tyres are the single most safety-critical component on your car, and the cost of a new set is nothing compared to the cost of an accident caused by tyre failure.