Vehicle registration

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Structurally modified vehicles

If you modify a chassis, monocoque bodyshell or frame to change the dimensions or appearance of the vehicle, this is known as a ‘structural modification’. 

You must tell DVLA if you make a structural modification to a vehicle.

Modifications should only be done by a specialist. You’re responsible for making sure your vehicle is always safe to drive.

There’s a different process to tell DVLA if you replace the chassis, monocoque bodyshell or frame to match the manufacturer’s specifications.

You do not need to tell them about any other repairs or restorations. 

What counts as structural modification

Structural modification of cars, motorcycles or light goods vehicles (under 3,500kg) can include:

  • altering the chassis, monocoque bodyshell or frame (for example changing the shape so it looks like a different vehicle type)
  • lengthening, shortening or widening the frame of a motorcycle
  • cutting, lengthening, or shortening roof pillars
  • removing the roof
  • removing an integrated roll cage
  • modifying or removing load-bearing sub-frames or support members
  • making additional holes within 30cm of a suspension, steering, braking or seatbelt mounting point
  • turning a motorcycle into a tricycle

You also need to tell DVLA if you modify a vehicle by converting it to run on electricity, even if you do not make structural modifications like changing the appearance.

See what else may count as a structural modification.

After you make the change

You should have your vehicle MOT checked and ensure your vehicle insurance is still valid.

You can get an individual vehicle approval inspection (IVA) instead of an MOT if you have a car.

Turning a motorcycle into a tricycle

If you turn a motorcycle to a tricycle using a conversion kit or plan, it must be registered as a kit-converted vehicle.

If you did not use a conversion kit or plan, you must tell DVLA about the structural modification.

If the vehicle has a welded tricycle system, DVLA will need to issue a vehicle identification number (VIN). You’ll need to get motorcycle single vehicle approval (MSVA).

If you need to tell DVLA about a structurally modified vehicle

Complete form V627/3 - ‘Modified vehicle statement’.

Send it to ‘Kits and Rebuilds’ at DVLA along with: 

  • the vehicle log book (V5C)
  • evidence of a current MOT, IVA or MSVA (if required)

Kits and Rebuilds  
D10
DVLA
Swansea  
SA99 1ZZ 

After you tell DVLA about a structurally modified vehicle

DVLA will issue a new registration certificate (V5C) which states that the vehicle has been modified from the original manufacturer’s specification.

The vehicle will usually keep the original VIN. DVLA will tell you if there’s a reason it cannot.

If your vehicle cannot keep its original registration number

DVLA will give your vehicle a registration starting with ‘Q’ if its age or identity is in doubt.

View a printable version of the whole guide

Part of Buy a vehicle: step by step

  1. Step 1 Check the vehicle before you buy it

    You'll need the vehicle's registration number, make, model and MOT test number. You also need to see the V5C vehicle registration certificate (log book).

    1. Check the details you've been given match DVLA's information
    2. Check the vehicle's MOT history
    3. Check if the vehicle has been recalled because of a safety issue
    4. Check the log book is not for a stolen vehicle

  2. Step 2 Buy and register the vehicle

    Once you've bought the vehicle, you have to register it. How you register it depends on whether it has a V5C registration certificate (log book).

    1. Find out how to register your vehicle
    2. Get a vehicle log book if you do not have it £25

  3. and Register for MOT reminders

    You must get an MOT for your vehicle every year once it's 3 years old.

    1. Get a reminder when your MOT is due

  4. Step 3 Insure the vehicle

    You must have insurance before you can use your vehicle on the road.

    1. Check if your vehicle is insured on the Motor Insurance Database
    2. Read about vehicle insurance

  5. Step 4 Tax the vehicle

    You need to tax the vehicle before you can use it on the road.

    1. Check how much you’ll have to pay to tax your vehicle
    2. Check when you do not have to pay vehicle tax
    3. Tax your vehicle