Vehicle Excise Duty
Motorhomes are classified as Private Light Goods Vehicles or Private Heavy Goods vehicles as defined below. However, in some cases motorhomes have been, incorrectly, registered under the graduated VED scheme for private cars. In this case, depending on the rating, some people may be paying more than they should be. The only known motorhome base vehicles to which this applies at present are those based on the Volkswagen Transporter. Your dealer can advise on the rates for these. The DVLA recognises this irregularity and is able to change the registration of vehicles on the graduated VED scheme - this can be done at your local vehicle licensing office.
Otherwise motor caravans with a Maximum Technically Permitted Laden Mass (MTPLM) of 3500 kg are Private Light Goods Vehicles. Motorhomes with a MTPLM of over 3,500kg are Private Heavy Goods Vehicles. Over and above this, some base vehicles use an engine deemed to polute less: E4 or E5, for which there are reduced rates.
For the current rates see the Directgov website.