Many people think a class B licence only lets you tow a small trailer, but the rules are more flexible than that. How heavy a trailer you can actually tow depends on three numbers: the car’s permitted gross weight, the trailer’s permitted gross weight, and the sum of the two – called the combination weight. In this article we show you how to calculate trailer weight for class B, and when you need an upgrade with code 96 or class BE.

Overview of trailer weight and licence for class B

Table of contents

The two main rules for class B

With an ordinary class B licence you can tow a trailer in two ways:

  1. Light trailer: You can always tow a trailer with a permitted gross weight of up to 750 kg, regardless of how heavy the car is. In that case you do not need to calculate the combination weight.
  2. Heavier trailer: You can tow a trailer over 750 kg as long as the total combination weight – the car’s and trailer’s permitted gross weights added together – does not exceed 3500 kg.

So it is not the trailer’s actual load that counts, but the permitted gross weight listed in the registration document. To understand the terms better, we recommend weight terms for passenger cars and the overview of trailer requirements for class B .

How to calculate the combination weight

To know whether a combination is legal on a class B licence, do the following:

  • Find the car’s permitted gross weight in the registration document (field F.2).
  • Find the trailer’s permitted gross weight.
  • Add both figures together.
  • If the sum is under 3500 kg, the combination is legal on class B.

You must also check the car’s permitted trailer weight (coupling load), which is the maximum the trailer can weigh behind your specific car. This figure is also in the registration document, and it can be lower than what the licence allows. Read more in the article on car, trailer, registration document and coupling load .

Code 96 and class BE

If 3500 kg is not enough, there are two upgrades:

LicenceWhat it givesMax combination weight
Class BTrailer ≤ 750 kg, or combination3500 kg
Code 96 (B96)Heavier trailer without a road test4250 kg
Class BEHeavy trailer with its own licencetrailer up to 3500 kg

Code 96 is obtained through a short course at a driving school and lets you drive combinations up to 4250 kg. Class BE requires its own practical driving test and lets you tow a trailer with a permitted gross weight of up to 3500 kg behind a class B car. For a thorough comparison, see code 96 vs class BE and the overview of licence categories .

  • Car 1900 kg + luggage trailer 700 kg: Legal on class B, since the trailer is under 750 kg.
  • Car 2100 kg + trailer 1300 kg: Combination 3400 kg – legal on class B.
  • Car 2500 kg + trailer 1700 kg: Combination 4200 kg – requires code 96.
  • Car 3000 kg + trailer 3200 kg: Combination 6200 kg – requires class BE.

Remember that an incorrectly loaded or overweight trailer worsens handling. Read what can happen with heavy loads and overloading , and how to find the right load distribution and nose weight .

Common misunderstandings

A common mistake is to think it is the load in the trailer that counts. That is not the case – it is the trailer’s permitted gross weight that applies, even if the trailer is towed empty. Another misunderstanding is that class B always stops at 750 kg; in practice you can tow far heavier trailers as long as the combination stays under 3500 kg.

Also be aware that separate speed limits with a trailer apply, and that a poorly coupled trailer can start to sway at speed. See speed limits with a trailer and trailer sway – causes and measures .

Want to practise questions about weight, combinations and licence categories before the test? Take a free theory test and keep practising in the Eteo app until you are ready for the theory test.