Your tyre tread is the only part of your car actually touching the road, so keeping it within legal limits matters for your safety and your Warrant of Fitness (WOF).
What's the legal minimum in New Zealand?
The legal minimum tread depth in New Zealand is 1.5mm, measured across the principal grooves and around the entire circumference of the tyre. Tyres below this depth will fail a WOF inspection and are illegal to drive on.
Legal isn't always safe
While 1.5mm is the legal cut-off, many safety experts recommend replacing tyres once they reach around 3mm, especially if you regularly drive in wet conditions. Below 3mm, braking distances on wet roads increase noticeably as your tyres lose their ability to channel water away from the contact patch.
How to check your tread depth
- Look for the tread wear indicators — small raised bars moulded into the main grooves. When your tread is level with these bars, you've hit the legal minimum.
- Use a tyre tread depth gauge for an accurate reading in millimetres.
- Check at least three points across the tread (inside, centre, outside edge) and at a few points around the tyre — uneven readings can point to alignment or pressure issues.
If you're not sure where your tyres stand, bring them in and we'll check your tread depth for you.