The short answer
A motorhome up to 3,500 kg permitted total mass can be driven on class B. Above that you need class C1, which is trained and tested separately. The real problem with 3.5-tonne motorhomes is not the licence but the payload: water, gas, bikes and four people fill the margin faster than the brochure suggests.
This question reaches us in spring, from about March onwards, and almost always in the same form: "I have rented a motorhome — is my licence enough?" Usually yes. What can go wrong afterwards is the more interesting part.
The limit
What counts is the permitted total mass of the motorhome, not its length and not its height. Up to 3,500 kg class B applies and the normal car rules apply with it. Above that, C1 begins. Rental companies therefore build most of their fleets to stay under the limit — the same calculation, seen from their side.
Why the payload is the real subject
- A fitted-out 3.5-tonne motorhome often uses most of that mass empty
- Fresh water weighs a kilogram a litre — a full tank is not a detail
- Gas bottles, awning, a bike rack with two e-bikes: that runs into three figures quickly
- Four people with luggage come on top, and children are not a rounding error here
- Overloading is an offence and it is checked — on holiday routes in particular
Almost everybody who arrives with this question has looked up the licence class beforehand and never the payload. So we now say both in one sentence, even when only one was asked about. The feedback afterwards is remarkably often the same: that the weighbridge at the filling station was the real surprise, not the authority.
With a trailer behind it
Then the same arithmetic applies as for any combination: a trailer up to 750 kg is always allowed, anything heavier only while motorhome and trailer together stay within 3,500 kg — which with a 3.5-tonne vehicle is arithmetically impossible. In practice that means a heavy motorhome plus a trailer puts you at B96 or BE, and the arithmetic is in the 4,250 kg calculation.
What the rental company asks on top
A minimum age and a minimum time since you passed are contract terms, not regulations. They are not in the licensing rules but in the rental agreement — and they are the second reason somebody with a valid class B gets turned away at the counter.
If you do not feel confident driving a vehicle that size, that is a separate and entirely normal point: a couple of refresher lessons beforehand change more than any amount of reading.
What to take away
With a motorhome the licence question turns on a number you can look up in two minutes. The question that actually causes trouble is the next one: what you may load once the vehicle is already close to its limit.