Structurally Modified Vehicles
Vehicles that have been subject to more substantial upgrade or modification from original specification than under the Repair or Restoration category. You must always notify DVLA when a vehicle has undergone work that qualifies as a Structural Modification.
DVLA policy changes in August 2025 introduced clarity on modifying vehicles. Structural Modifications include electric conversions, cutting into or shortening a vehicle’s chassis (separate chassis) or frame for motorcycles. Modifications to a monocoque bodyshell such as removing a roof or altering pillars, and changing a vehicle’s appearance or dimensions from its original manufacturer’s specification.
It is important to note that cutting into the above components for repair without changing the original specification (for example, replacing a section which is damaged or rusted), is classed as a Repair or Restoration.
Structurally Modified vehicles qualify for an age-related or original registration number (VRN) in most cases provided the vehicle identity is not in doubt. The DVLA will update the V5C logbook with a relevant marker stating a modification.
Important: Always refer to DVLA full guidance INF318
Notify DVLA:
DVLA must be notified in all instances where a vehicle qualifies as Structurally Modified using form ‘Modified vehicle statement’ (V627/3).
Other notifications:
You should notify your insurance company of any modification from original specification.
An MoT is required as part of the notification process in many cases following Structural Modification, even where a vehicle is exempt as Historic. See the MoT requirements for modifications.
Examples of the revised Structurally Modified policy:
Alvis TD21 coupe conversion to DHC convertible
Peter inherited his grandfathers Alvis TD21 Series 1 saloon that he has fond memories of, but sadly it has been stored and unused since the late 1970s.
The original VE60 ‘green’ log book is still with the car, although the DVLA record was not updated to the V5 style registration document in the early 1980s.
Q: Can Peter contact DVLA to retain the original registration number, issued in 1961 and featured in family continental holiday photos within the car’s history file?
A: Yes, by applying via the V765 form and process to register a vehicle under its original registration.
Having embraced the restoration project, Peter’s ultimate Alvis would be the drophead (convertible) model.
Q: As part of the restoration, can Peter have the Alvis altered from the original saloon body to a convertible?
A: Yes, although he will need to notify DVLA since this will qualify as a modification to the vehicles appearance from the original factory supplied specification under the ‘Structurally Modified’ rules and these details will need to be updated on the V5C.
Q: Will the original identity and chassis number (VIN) of the Alvis be in jeopardy?
A: No, the original VIN and the original registration number (subject to DVLA acceptance of the V765 application) will be retained, with a special note on the V5C to reflect ‘a modification’ which will help to inform any future buyer that the Alvis was originally built as a saloon, as clearly identified within the original manufacturer VIN coding.
Rover P6 electric conversion
Dan and Emily live in London. They love the idea of a classic car, but for them a classic converted to run on electric is their ideal preference based on their intended use. They have fallen in love with a neighbour’s cherished 1969 Rover P6 which currently has a blown engine. This could be the perfect project for them to convert to electric.
Q: If Dan and Emily purchase the Rover, will it retain the original registration number if they convert it to electric?
A: Yes, along with the original Rover allocated chassis number (VIN).
Q: Do they need to notify DVLA of the change of power unit?
A: Yes, the change of motive power will qualify under the ‘Structurally Modified’ category rules and it is extremely important that DVLA are notified because the information in the vehicle details section of the V5C will change. It is also vital information to protect the emergency services in the case of the Rover ever being involved in an accident, for example.
Q: How is the vehicle registration document (V5C) affected?
A: A special note will be added to record that the vehicle has been modified and motive power changed to Electric.