The first point is that the maximum trailer weight is controlled by the towing capacity of the vehicle (See Table 1). Every type of vehicle is designed to tow a maximum weight depending on the specification size and braking efficiency of the vehicle.

In all probability, a typical family saloon would not be legally allowed to tow a loaded double horsebox or a livestock trailer over 8ft x 4ft. Every trailer is designed by the manufacturer to carry the weight intended for use.

Some specifications may require a double or single axle or even triple axle trailer to carry out the task. Trailer manufacturers differ in the weights that each axle can carry. This is up to the manufacturer’s specification choices to meet certification guidelines.

Trailers using triple axles are often longer to carry longer items such as boats, bales and timber beams, not entitling them to go over 3,500kg.

Myth

Family cars are not allowed to tow double-axle trailers. This is not true. A car can tow a trailer up to 750kg unbraked, regardless of the number of axles fitted.

In reality, this will not happen as a trailer of this class will only use one axle to reduce weight and increase the payload in the trailer. If the trailer is braked, family saloon cars can tow between 1,600kg and 2,000kg, including the weight of the trailer. It is of benefit to have a lighter trailer when the trailer is unbraked. Trips to the dump and occasional meal runs can be achieved keeping under the 750kg limit.

Fact

The legal speed of any towing vehicle is 80km/h on the road. The 120km/h speed limits no longer apply when towing any trailer.

Myth

The more axles on the trailer, the more weight I can carry. This is not true – the weight is governed by the towing vehicle. The rating on the vehicle will determine how much load can be placed in the trailer. The trailer by design must also be capable of handling the weight. Plates found on the side or drawbar will specify the weight certified for load on the trailer.

Fact

All trailers capable of holding 750kg and over are required to have their own braking system.

License requirements

A category B driving licence authorises you to drive a car, van or 4x4 which has a maximum mass (as specified by the manufacturer) of not more than 3,500kg and is designed and constructed to carry no more than eight passengers in addition to the driver.

You may tow a trailer with a maximum mass (again as specified by the manufacturer) not greater than 750kg, or where the maximum mass is more than 750kg, the combined maximum mass of the towing vehicle and the trailer is not greater than 3,500kg.

To put it simply, if the vehicle and the trailer in combination is over 3,500kg, this category of licence will not be legal. There is one scenario that allows more than 750kg to be towed in the trailer.

For example, if towing a trailer using a Volkswagen Passat that has a gross vehicle weight of 2000kg, then a trailer carrying 1,500kg including its own weight is legal as it is under the maximum authorised mass (MAM) of 3,500kg.

Towing the exact same trailer with a Land Cruiser would push the driver over the weight limit, requiring them to apply and pass the test for a category BE licence. With BE, the trailer and load can weigh up to 3,500kg and your vehicle can weigh up to the same maximum of 3.5t, bringing the combined weight to 7,000kg.

Another interesting point here is that the Volkswagen Passat is certified by the manufacturer to tow 2,000kg. This would push this car and combination into the BE licence category. The number of axles on the trailer has nothing to do with licence requirements – it is all down to weight.

Conclusion

The best advice is to find out the towing capacity of the vehicle you are using, and to ensure that you have the correct category of licence for the combination in use.