Towing a trailer and my driving licence: It all seems so confusing :s

Do I need to upgrade my driving licence to be able to tow a trailer?

Since 1997, anyone who has passed their car driving test (Category B) is not legally allowed to tow a trailer over 750kg (Cat B+E), drive a minibus with more than 8 seats (Cat D1) or drive a van if the gross vehicle weight (or Gross Laden Weight) is more than 3500kg but not more than 7500kg (Cat C1)…  Got that so far? Shame is doesn’t stay that simple!!

The towing vehicle:

Cat B is a vehicle with 2 axles and a maximum gross vehicle weight of 3500kg.  Gross vehicle weight is the weight of the vehicle plus any load it is CAPABLE of carrying (Payload).  CAPABLE is the key word, it doesn’t necessarily need to carry that weight – put that aside for later please.

Each vehicle will also have a Maximum Authorised Mass (MAM).  This is the GVW of the car plus the gross weight of the trailer (weight of trailer plus load it is CAPABLE of carrying, even if it is not going to be carried)  This was previously known as the Gross Train Weight (GTW)  To work out the permissible towing weight a vehicle can tow, subtract the GVW from the MAM.  Example:

  •   Cat B MAM = 5300kg
  •   Cat B GVW  = 3300kg.

In this example the permissible towing weight must NOT exceed 2000kg (remember that this will be the actual weight of the trailer plus the load (payload) it is capable of carrying.

With the example above if the trailer’s unladen weight is 800kg, the load it is capable of carrying will be 1200kgHopefully so far so good?

The trailer:

A trailer over 750kg is any item that has an axle, or axles (the more axles the more weight it is capable of carrying – normally!) and is braked (the wheels have a means of a force that can be applied to slow the rotation of the wheels when attached to a vehicle, such as drum brakes, disc brakes.  They normally have  handbrake too).  A trailer could be a horse-box trailer, a caravan, a boat trailer, jet ski trailer, a car transporter, a  box van trailer, a flat-bed or caged trailer to carry stock or plant equipment.  Plant equipment such as a generators or water bowsers may also be trailers too, or any other type that I haven’t mention. (side note – a litre of water is equivalent to 1kg, important if you have a shower unit trailer or 100o litre water bowser)

Time to recap:  If a Cat B GVW is 3500kg and has an unladen weight of 2500kg, it could carry 1000kg of payload.  Furthermore, it may have a MAM of 6600kg so it also could tow a loaded trailer, such as a horse-box or a flatbed with a digger up to the weight of 3100kg. Happy so far?

The combination or outfit

It is important to identify the weight plate of a vehicle and the trailer to ensure that you do not end up towing an unsuitable combination.  For instance:

  •  A Land Rover Freelander 2 has a MAM of 4505kg and the GVW is 2505kg.  The maximum permissible towing weight for this vehicle is 2000kg.*
  • A Land Rover Discover 4 has a MAM of 6740kg and a GVW of 3240kg.  The maximum permissible towing weight for this vehicle is 3500kg*

 The Ifor Williams HB506 horse-box trailer’s unladen weight is 920kg and the Gross Weight is 2600kg.**

Quick quiz:

  1. Can the Land Rover Freelander 2 tow the HB506 with horses in transit?
  2. Can the Land Rover Freelander 2 tow the HB506 with the horse-box empty?

Hopefully you have answered NO! to both.

Q1 is NO! because the gross weight of the HB506 is heavier than the permissible towing weight of the Land Rover Freelander 2.  Towing a trailer that has a Gross Weight heavier than the towing vehicles GVW is very unsafe as it could make the handling characteristics of the towing vehicle unpredictable such as braking.  (a trailer heavier than the car with only trailer overrun brakes!!!!)  It will also cause unnecessary wear and premature failure to the clutch mechanism.

Q2 is NO! because the gross weight of the HB506 is heavier than the permissible towing weight of the Land Rover Freelander 2.  It makes no difference whether the trailer is empty or laden, it is always based on the CAPABILITY it can carry (Remember that from earlier… you put it aside, remember)  Although the unladen weight of the trailer is 920kg, it is the Gross Weight that must be taken into account, even it the trailer is empty.

To conclude:

Hopefully that clarifies when a B+E licence is needed.  So if a car has a GVW of 2100kg with a MAM of 3490kg and the trailer weight is 1300kg, the driver needs to have Cat B+E on their licence?

  • Answer: NO! NO! NO!

Here lies the confusion: If the combined Gross Weight of the trailer and the vehicle MAM is less than 3500kg (in the above example 3300kg) and it is a suitable combination or outfit, then that combination can be driven on a Cat B licence without the need for Cat +E. (The gross weight of the trailer must not exceed the unladen weight of the vehicle)

Hopefully that clears the confusion.  So if the car has an unladen weight of 1250kg and a GVW of 1950kg with a MAM of 3490kg and the trailer weight is 1300kg, the driver does not need to have Cat B+E on their licence?

  • Answer: NO! NO! NO!

Although the combined Gross Weight of this example is 3250kg, because the Gross Weight of the trailer (1300kg) is more than the unladen weight of the car (1250kg) a B+E licence is required.

As a general rule, when towing a caravan, the Gross Weight of the caravan should not normally exceed 85% of the unladen weight of the towing vehicle.


If a the Gross Weight of a trailer is 800kg and the towing vehicle’s GVW is 2650kg, this combination can be towed with a Cat B licence.  Put the same trailer on a vehicle with a GVW of 2750kg, the driver of this combination will need Cat B+E on his licence.  How simple is that???

Towing a car that has broken down also counts as a trailer.  Cat B+E will be needed to tow a broken down car, the only exception is to move a broken down vehicle from a dangerous position to a safe position and is not to be towed longer than necessary unless the driver holds Cat B+E.

For more information, email us and we will see if we can help with the confusion.

Coming up…. Trailer towing training… The need for tachographs when towing trailers… Clarifying when Cat D1 is needed… Section 19 for D1… Clarifying when Cat C1 is needed… More on trailer weights and loads.

Footnotes: * source: Land Rover official website.  **source Ifor Williams official website