Towing law in Australia is a mix of national rules that apply wherever you are and state-level rules that change when you cross a border. Most of the equipment requirements — chains, brakes, breakaway systems, mirrors — are consistent nationwide because they flow from national vehicle standards. What varies is the road-rules layer each state and territory administers: speed limits when towing, maximum dimensions, and the licence you need for heavier combinations.
This guide is the hub. It covers the national rules in enough detail to be useful, flags the areas that differ by jurisdiction, and points you to the authority that has the final say in your state. Treat it as your starting map, then confirm the specifics with your own state's road authority before a big trip — the details are theirs to set and to change.
The Rules That Apply Everywhere
These requirements come from Australia's national vehicle standards and apply in every state and territory. The thresholds below are keyed to your trailer's GTM (Gross Trailer Mass, the load on the caravan's own axles) and ATM (Aggregate Trailer Mass, the total loaded weight). If those terms are unfamiliar, our guide to towing weight ratings explains them.
Trailer Brakes
Braking requirements step up with weight:
- Up to 750 kg GTM: no brakes required.
- Over 750 kg and up to 2,000 kg GTM: brakes required on at least one axle.
- Over 2,000 kg GTM: brakes required on all wheels, and a system that automatically applies the trailer's brakes if it detaches from the tow vehicle.
Most modern caravans sit in the "over 2,000 kg" band, which means electric or electric-over-hydraulic brakes on every wheel plus a breakaway system.
Breakaway Systems
A breakaway system applies the caravan's brakes automatically if the van separates from the tow vehicle — the single most important piece of equipment for preventing a runaway trailer. It is mandatory for trailers over 2,000 kg GTM, and it relies on a small onboard battery. If your van has been in storage, check that battery before you travel: a flat breakaway battery means no emergency braking exactly when you would need it most.
Safety Chains
Safety chains are the mechanical backup that keeps the drawbar off the road if the coupling fails. The number and rating scale with the trailer's ATM:
- Up to 2,500 kg ATM: one safety chain.
- Over 2,500 kg and up to 3,500 kg ATM: two safety chains.
- Over 3,500 kg ATM: two chains made from rated (T-grade) chain.
Chains must be crossed under the drawbar so they cradle it if the coupling lets go, and shackles should have a breaking load comfortably above the trailer's ATM. Do not substitute hardware-store shackles rated below your van.
Towing Mirrors
If your caravan is wider than your tow vehicle — which almost all of them are — your standard mirrors will not give you a clear view down the sides and behind. Extended towing mirrors are required whenever the vehicle's existing mirrors cannot provide that clear rearward view. This is a genuine legal requirement, not a nice-to-have.
Coupling, Load Security, and Lights
Universal across the country: the coupling must be rated to your ATM and correctly secured; the load must be restrained so nothing can fall or shift; and all trailer lights — tail, brake, indicators, number plate — must work. These all feature on our pre-trip towing safety checklist, which is worth running through every time you hitch up.
The Rules That Change at the Border
Speed Limits When Towing
This is the area travellers most often get wrong, because the rule genuinely differs by state:
- Western Australia applies a maximum of 100 km/h when towing, regardless of the posted limit or your rig's weight.
- New South Wales allows towing at the signed limit for most light rigs, but caps vehicles with a GVM over 4.5 tonnes at 100 km/h.
- Victoria, Queensland, South Australia, the ACT, and the Northern Territory set no special towing speed limit — you follow the posted limit and, critically, adjust down for conditions.
- Tasmania follows the posted limit (typically 100 or 110 km/h on highways) for vans under 12 tonnes, and expects lower speeds on unsealed roads.
We cover this in depth, including why the posted number is a ceiling and not a target, in our guide to towing speed limits by state.
Licensing
A standard car licence covers most caravan and tow-vehicle combinations, but there is a limit. Very heavy combinations — typically where the combined weight or the tow vehicle's GVM crosses into light-truck territory — can require a light rigid or medium rigid licence class. The exact thresholds and class names are set by each state's licensing authority, so if you are running a large American-style pickup or a combination near the heavy end, confirm your licence covers it.
Maximum Dimensions
National limits cap trailer width (generally 2.5 metres) and set height and length maxima, but states administer the rules around oversize loads, rear overhang, and what requires a permit. If your rig is unusually long or wide, check your state's requirements.
Where to Confirm the Details
For anything specific to your situation, the authoritative source is your state or territory road authority — Transport for NSW, VicRoads, Queensland's Department of Transport and Main Roads, South Australia's DIT, Western Australia's Department of Transport, TasRoads, the NT's MVR, or Access Canberra. Motoring bodies such as the NRMA, RACV, RACQ, and RAA also publish plain-English summaries that are a good cross-check.
The one thing no authority can tell you remotely is whether your rig, loaded the way you actually pack it, sits within its legal weights. That requires weighing — see how to use a weighbridge.
Get Your Compliance Picture in One Place
Staying legal starts with knowing your numbers. Ready2Tow lets you enter your vehicle and caravan specifications and checks your GVM, ATM, GCM, GTM, and ball weight against their limits, using the correct terminology for your region. It performs a point-in-time arithmetic check on the figures you enter or measure — it is not a live lookup of your local regulations, and it does not replace reading your state's rules or weighing your rig. Colour-coded results show which ratings are safe and which need attention. See the comparison page for what it does that a spreadsheet cannot.
Ready2Tow provides weight and tyre pressure calculations as a guide only. It does not replace professional weighing services, qualified tyre technicians, or the road rules published by your state authority. Always verify your weights at a certified weighbridge before towing.
