On a B licence you are allowed a tow car/trailer combined gross weight of 3500kg. If you have an E category as well ( which was given to drivers passing their tests before 1997 ) you can go large. It is important to remember that it is the manufacturers gross figures that count. This means that a post 97 driver with a Minno grossing 1400 kg would be able to tow it with a gross vehicle weight of 2100 kg or less, assuming that vehicle has a towing capacity of 1400kg! If you need a wider trailer with a higher gross rating, and this would put you slightly over the 3500 limit, it might be possible to ask the manufacturer to de-rate it, although this might then limit it's future use. If you definitely need to go over 3500, think 4 x 4 towing decent size trailer, you will need to take trailer test, E. A B licence will also allow you a gross combined of 4250kg, but only if the trailer grosses 750kg or less, so can be discounted for 7 towing purposes. Your licence will say what categories you have, and all the weights will be on trailer plate and vehicle plate/handbook.