How To Make Sure Your Tyre's Tread Depth Is NOT Illegal

Australian light-vehicle tyres must maintain at least 1.5 mm tread depth in a continuous band comprising the central three-quarters of the tread width around the full circumference. Police and inspectors use gauges; insurance may dispute claims on illegal tyres.

Measure correctly

Measure in the main grooves, not on shoulder blocks. Take several readings — some tyres wear more in the centre (over-inflation) or shoulders (under-inflation or alignment).

Legal minimum vs safe minimum

1.5 mm is a floor, not a target. Many safety bodies recommend replacing summer/all-season tyres before they reach 3 mm if you drive in heavy rain.

Spares and motorcycles

The same principle applies to full-size spares you might deploy long-term. Motorcycle and truck rules differ — always check your jurisdiction and vehicle class.