Axle group mass limits, as of 1 August 2026
The limits below are the general mass limits that commenced on 1 August 2026, when the old concessional limits became the general ones. Anything published before that date is stale. Each figure links to the NHVR document it was read from, checked on 6 August 2026, and the checker underneath totals your own axle weights against them.
| Axle group | Applies to | Limit | Source |
|---|---|---|---|
| Single steer axle | Standard motor vehicleComplying steer axle vehicles are allowed 6.5t, and eligible Euro VI (ADR 80/04) vehicles up to 7.0t. Unchanged by the 1 August 2026 amendment. | 6t | NHVR GML fact sheet |
| Single axle, dual tyres | Not a pig trailer or busPig trailers are limited to 8.5t on this configuration. Unchanged by the 1 August 2026 amendment. | 9t | NHVR GML fact sheet |
| Twinsteer axle group | Load-sharing suspension10.0t without load-sharing suspension; eligible Euro VI twinsteer groups up to 11.5t. | 11t | NHVR GML fact sheet |
| Tandem axle group | Dual tyres, not a pig trailerRaised from 16.5t on 1 August 2026. Pig trailer tandems stay at 15.0t. | 17twas 16.5t | NHVR changes fact sheet |
| Tri-axle group | Dual tyres or single tyres at least 375mm, not a pig trailerRaised from 20.0t on 1 August 2026. Pig trailer tri-axle groups stay at 18.0t. | 21twas 20t | NHVR changes fact sheet |
| Quad-axle group and groups of 5 or more | Dual tyres or single tyres at least 375mmRaised from 20.0t on 1 August 2026 to stay aligned with tri-axle groups. | 21twas 20t | NHVR changes fact sheet |
Check your axle group weights
Enter what each group weighs, off a weighbridge docket or the loading plan, and see the headroom against each group's general mass limit.
Reading the answer
Where these numbers come from
The tandem 17.0t, tri-axle 21.0t and quad 21.0t figures are from the NHVR's Changes to heavy vehicle mass and size rules fact sheet (1 June 2026), which states the amendments commencing 1 August 2026. The steer, single axle and twinsteer figures, which the amendment did not touch, are from the NHVR's General Mass Limits fact sheet (24 February 2026). Both were checked on 6 August 2026. The definitive legal table is Schedule 1 of the Heavy Vehicle (Mass, Dimension and Loading) National Regulation, via the NHVR general mass limits page.
What this table deliberately is not
It is general mass limits only, for the common line-haul configurations. Pig trailers, buses, and single-tyre tandem and tri-axle groups run to different rows of the regulation; HML adds mass for accredited operators on approved routes; PBS vehicles carry their own approvals. If your configuration is not plainly one of the rows above, confirm it with the NHVR rather than reading the nearest row as close enough.
Group limits are not a licence to load to them
The regulation caps how much extra a whole combination gains from the August 2026 increases, at 1 tonne below 55 tonnes total and 2 tonnes above, and the manufacturer's GVM, GCM and tyre ratings all still bind. Mass is also not access: a mass-compliant road train is still a road train and only travels approved routes. The only number that settles an argument at the depot is a weighbridge docket.
Common questions
What are the axle mass limits in Australia after 1 August 2026?
Under general mass limits: 6.0t on a standard single steer axle, 9.0t on a single axle with dual tyres, 11.0t on a load-sharing twinsteer group, 17.0t on a tandem group with dual tyres, and 21.0t on tri-axle and quad-axle groups. The tandem, tri and quad figures were raised on 1 August 2026 from 16.5t, 20.0t and 20.0t when the former concessional limits became the new general limits.
What changed on 1 August 2026?
General mass limits were raised to the former concessional (CML) levels and CML was abolished as a category: tandem groups went from 16.5t to 17.0t and tri-axle and quad groups from 20.0t to 21.0t. Combination totals rise by at most 1 tonne below 55t and 2 tonnes above, mass management accreditation is no longer needed just to run the new limits, the prescriptive length limit rose from 19m to 20m for several combinations, and eligible Euro VI road train prime movers gained a 7.0t steer concession. Higher Mass Limits did not change.
If every axle group is under its limit, is the load legal?
Not necessarily, and this tool never says legal. The manufacturer's GVM and GCM can bind below the group limits, the regulation caps how much of the group increases a combination may actually use, tyre ratings must cover the group mass, and mass says nothing about route access: HML, PBS, road trains and oversize all involve separate approvals. Treat a green result here as a reason to weigh the vehicle, not a reason to skip the weighbridge.
Do these limits apply in Western Australia and the Northern Territory?
No. The Heavy Vehicle National Law does not apply in WA or the NT; both run their own mass and dimension regimes. For vehicles operating there, check Main Roads WA or the NT road transport authority rather than this table.
Working out what the whole truck can carry rather than each group? That is the payload calculator.
Buying for the new limits?
The August 2026 changes made tri-axle trailers and tandem-drive trucks worth more per trip. Listings here carry axle configuration and ATM so you can shop for it.
Browse trailersGeneral information, not legal advice, and not route access. The Heavy Vehicle National Law does not apply in WA or the NT. Figures checked against the NHVR sources linked above on 6 August 2026; the regulation as in force at legislation.qld.gov.au prevails over any summary, including this one.