towing a horsebox

[Administrator]

Towing weights & the law

Before towing it is essential that you check your towing vehicle is capable of legally towing your fully laden horse trailer
If you don’t take heed not only are you putting yourself, your horses and other road users at greater risk of accident
but you also risk a fine if stopped and found to be contravening the law
In the event of an accident, your insurance will be also invalidated

as a basic guide the unladen weight of the trailer, plus the weight of the heaviest horses to be towed must not exceed the trailer’s maximum authorised mass. This, in turn, should not exceed the car’s maximum towing weight

so, first of all you need to find out is
the combined weight of the two (or more, for multi-horse trailers) largest horses you wish to travel
 
The trailer’s unladen weight and maximum authorised mass (MAM)
 
Your proposed towing vehicle’s maximum towing capacity (MTC)
 
Calculations

(combined weight of horses + unladen trailer weight) should be below or equal to trailer’s MAM

(combined weight of horses + unladen trailer weight) should be below the towing vehicle’s max. towing capacity

IMPORTANT: Remember you need to allow for the weight of tack / feed / water when calculating the load as this will count toward the maximum towing capacity
Therefore horses + trailer weight that equals exactly the car’s max towing capacity is still not legal

Examples
Horses: 15hh m/w @ 500kg + 16.3hh TB @ 600kg = combined weight 1100kg
Trailer: Ifor Williams 510 @ unladen 1000kg; MAM 2700kg (fine with above horse combination)

Horses + Trailer gross weight = 2100kg

Vehicle Mitsubishi Outlander with a Maximum towing capacity of 2000kg Illegal
This vehicle does not have the authorised towing capacity to tow the gross weight of the horses and the trailer

Vehicle Landrover Discovery with a maximum towing capacity of 3500kg Legal
This vehicle is well within the capacity needed to tow these horses with this trailer
 
Considerations
So, you know the weight of your fully laden horse trailer and / or your towing vehicle's maximum towing weight, and the combination seems fine from a legal perspective. Before you hit the road, however, you should bear in mind the following
Have you remembered to allow for extra weight that will be in the horse trailer, including tack and equipment, feed, water etc. in your calculations? All need to be added to the combined weight of your largest horses
 
How close is the weight of your fully laden trailer (including above 'extras') to your towing vehicle's max. towing weight? If it's exactly on or just under it may sound legal, but from a safety perspective would be reckless. Allow a decent margin, i.e. at least a couple of hundred kilograms, to be safe rather than sorry
 
Number plates
When towing a horse trailer you have a legal obligation to ensure that number plate displayed on the rear of the trailer matches that of the towing vehicle and is legible
It is important to ensure you have a legal, reflective yellow plate fitted to the trailer as soon as you are able
 
a horse lorry

for the full vehicle and operators service agency guide to horse box and horse trailers please follow the link below

https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/193236/A_guide_for_horsebox_and_trailer_owners.pdf