Ask most transport managers what their trucks weigh and they will quote the gross figure - 44 tonnes, 32 tonnes, 26 tonnes. Ask them what each axle is permitted to carry and the answers get vaguer. That gap is exactly where overloading prosecutions live. A vehicle can be comfortably inside its gross weight limit and still be illegal because one axle is over its individual limit, and each overloaded axle is a separate offence for both the operator and the driver.
This guide explains how axle weight limits work in Great Britain, where the legal numbers for your vehicle actually come from, the classic ways fleets breach them without meaning to, and why the authorities care about axle weights as much as gross weights.
Every goods vehicle on the road is subject to two layers of weight limits simultaneously: the gross vehicle weight (and gross train weight for a combination), and the maximum weight each individual axle may carry. Passing one test does not excuse failing the other. The government’s overloading guidance gives the stark example: a 3-axle articulated vehicle exceeding its plated weights on the first axle, the second axle and the gross weight makes both the operator and the driver liable to three separate offences from a single load.
That multiplication is why DVSA roadside examiners weigh axles individually. A quick gross figure on a weighbridge tells you almost nothing about legality if the load is badly distributed.
There are two sets of statutory limits in Great Britain, set by two parallel regimes: the Road Vehicles (Construction and Use) Regulations 1986 (C&U) and the Road Vehicles (Authorised Weight) Regulations 1998 (AWR), which adopted the maximum weights from European Directive 96/53/EC from 1 January 1999. Vehicles may only comply with one of the regulations - you cannot cherry-pick individual parts from both.
In practice, though, the numbers that matter day to day are the ones fixed to your vehicle. The maximum permitted axle weight and gross vehicle weight appear on a manufacturer’s plate or a Department for Transport plate - usually found in the vehicle cabin, under the bonnet or, for trailers, on the chassis. Where a vehicle carries both, the Department for Transport limits are the legal limits in England, Scotland and Wales. If the plates disagree, the DfT plate wins.
To take one important example: for operation above 40,000kg, the drive axle must not exceed 10,500kg and must have road friendly suspension - or the maximum axle weight must not exceed 8,500kg. That single condition quietly caps what many 44-tonne combinations can actually carry on the driven axle.
The government’s overloading guidance calls out one failure mode by name: lift or tag axles used incorrectly. If a liftable axle is raised while the vehicle is loaded, the weight it was designed to share transfers to the remaining axles - and those axles can exceed their individual limits even though the gross weight is unchanged. “Make sure that your lift or tag axle is used correctly. Not using this axle when the vehicle is loaded means that axles or gross weights could exceed their allowed limits.”
This is an operational discipline issue, not a mechanical one. Drivers need to know when the axle must be down, and transport offices should treat an up-when-loaded axle as an overloading event, not a fuel-saving trick.
Axle overloads are usually a distribution problem. Common causes:
The practical defence is weighing. Weigh the vehicle to establish individual axle weights, check the gross vehicle weight before setting out using your own weighbridge or a nearby one, and remember you are allowed to drive to the nearest available weighbridge to check a load, and then to a place where some of the load can be removed if the vehicle proves overloaded. For fleets, the guidance recommends installing a fixed axle weighbridge or a portable axle weighing system.
Axle limits are not arbitrary. The structural road wear attributable to a vehicle is normally assumed to be proportional to the fourth power of the axle weight. Run the numbers and the effect is startling: a 10% increase in the weight imposed on a road by an axle is assumed to increase structural road wear by 46%, and a vehicle with twice the axle weight of another causes 16 times the wear. Bridges and pavements suffer the same arithmetic. This is why DVSA, the police and trading standards officers all have weighing powers, and why an overloading conviction is one of the factors that can lead a Traffic Commissioner to take disciplinary action against the operator’s licence.
A workable axle-weight routine has four parts. First, know the plated axle limits for every vehicle and trailer in the fleet, from the DfT plate where one exists. Second, weigh - axles, not just gross - at sensible intervals and whenever load patterns change. Third, train loaders and drivers on distribution: where the weight sits matters as much as how much there is. Fourth, write lift-axle use into driver instructions and check it.
Do those four things and the most common axle prosecutions simply cannot happen to you.