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NSW Tyre Size Laws - What's Biggest Legal Tyres You Can Fit?

Are you a vehicle owner from New South Wales? Do you know what the rules say about changing your tyre sizes?

Whether you’re considering upsizing or downsizing your tyres for performance or other reasons, let us help you navigate the confusing maze of tyre modifications with confidence!

NSW Tyre Size Laws

The laws around changing tyre sizes in New South Wales, Australia are outlined in the Vehicle Standards Information (VSI.09).

According to the VSI, tyres fitted to your vehicle must meet the construction standards set out in the Australian Design Rules (ADR 23). These standards ensure that the tyres used on your vehicle are safe and suitable for their intended purpose.

In addition to complying with ADR 23, there are specific restrictions on tyre sizes in NSW. It’s important to adhere to these restrictions to avoid potential fines and ensure your vehicle remains roadworthy.

Failure to comply with the regulations can also lead to insurance issues in the event of an accident.

Restrictions On Tyre Sizes In NSW

There are specific limits set by the NSW regulations when it comes to increasing the size of your tyres.


In NSW, you can install wheels up to 26mm wider than the manufacturer’s specifications without notifying the Road and Maritime Services (RMS).

This means you have some flexibility in terms of increasing the width of your tyres to achieve a desired look or performance.


You are not permitted to fit tyres that are more than 50mm bigger than the factory tyre diameter.

This restriction ensures that the overall diameter of the tyre remains within acceptable limits, preventing potential issues with vehicle clearance, speedometer accuracy, and handling.

For many four-wheel drive vehicles, 31-inch tyres are the standard size. Therefore, in NSW, the biggest legal tyre size you can fit is 33 inches.

Check out our guide on comparing tyre sizes to know more.


In New South Wales, when changing tyre sizes you must strictly adhere to the state’s laws and guidelines.

Understanding and following these rules will help make sure your vehicle remains safe, roadworthy, and compliant with the NSW tyre size regulations.

Still confused about how to read tyre sizes? Check out this article to get up to speed quickly!

Louis from Tyre Geek


I'm Louis, an engineer passionate about helping Australians choose better tyres for their vehicles!