Guidance

Making changes to a vehicle and registering kit-built, kit-converted and reconstructed classic vehicles (INF318)

Updated 3 August 2026

Introduction

Telling DVLA of changes made to a vehicle

There is a legal requirement to notify DVLA of any changes made to a vehicle which affects the information shown on the V5C registration certificate (log book) such as replacing the engine. Check when you need to update your V5C.

Vehicle safety

A vehicle keeper is responsible for making sure their vehicle is always safe to drive (‘roadworthy’). A vehicle can be unsafe even if it has a current MOT certificate as the MOT only tests the vehicle’s roadworthiness at the time of the test. There are penalties for driving a vehicle in a dangerous condition.

Find more information on roadworthiness and penalties.

Vehicles with personalised registration numbers

Not all registration numbers are transferable. Check your V5C registration certificate (log book) first. You may want to arrange a transfer or retain the registration number before you carry out any modifications or conversions.

Before you start

The INF318 leaflet provides guidance, but it does not cover every possible situation. You should identify and classify the changes made to your vehicle (for example, repair, structural modification or reconstructed classic) as accurately as possible and follow the relevant instructions.

You can (and should, if helpful), include extra information and supporting evidence to help DVLA process your application efficiently.

DVLA will contact you if your submission is incomplete or needs clarification.

DVLA cannot confirm the outcome in advance (such as inspection requirements, retaining the original identity, or issuing a new or ‘Q’ registration), as a full review of the evidence and vehicle record is required before any decision is made.

When to apply

You should only make your notification if your vehicle is fully built, complete and ready for road use. Applications submitted before this stage cannot be fully assessed and may be delayed or returned.

Part 1 – repairs, restorations and structural modifications

Repairs and restorations

Vehicles which have been repaired or restored

Unless the vehicle information shown on the V5C is affected (details held in the vehicle details section of the V5C), there is no requirement to notify DVLA where a vehicle has been repaired or restored to return it to its original working standard.

Repairs and restorations will include the replacement of worn-out components or body panels, on a like-for-like basis, and of the same standard as the originals. The appearance of the structural parts of the vehicle must be the same as when it was originally manufactured, or to a period-correct specification. Period-correct or period specific means consistent with what would have been available and commonly used at the time.

There is one ‘exception’ to the above, which is the like-for-like replacement of chassis, monocoque bodyshell or frame (for motorcycles) as this would be a notifiable repair - see the section on replacing a vehicle’s chassis, monocoque bodyshell or frame (for motorcycles).

While repair or restoration work will not affect a vehicle’s registration details, we advise that you present your vehicle for an MOT as a roadworthiness check of the work that has been done, as you are responsible for the roadworthiness of the vehicle. There are penalties for driving a vehicle in a dangerous condition.

It’s also advised that you contact your vehicle insurance provider to check whether the changes affect the motor insurance cover.

Examples of repairs and restorations for cars and light goods vehicles (under 3,500kg)

Repairs and restorations will include, but are not limited to the following:

• replacing a boot floor
• replacing footwells
• replacing front or rear wheel arches or adapting front or rear wings to allow for wider wheels
• replacing sills
• replacing steering or suspension
• replacing the gearbox or axles
• adding a roll bar or roll cage
• removing an existing roll bar or roll cage fitted post manufacture – any attachment holes left after removal must be welded over, using a continuous seam weld to return a vehicle to its original condition
• replacing damaged or corroded body panels
• replacing a like-for-like component or panel with one that is made from different materials with equal-to or better-than performance characteristics than the original
• corroded areas of the chassis or monocoque bodyshell repaired using a patch, but must be continuously seam welded
• replacement of sub-frames
• fitting seatbelts (providing these are fitted as per the manufacturer’s guidance)
• fitting period-correct accessories (for example, additional lamps, tow bars and radio aerials)
• alterations to the firewall or transmission tunnel to accommodate a different bell housing or transmission (vehicles with a separate chassis only – for a monocoque vehicle, this needs to be notified as a modification)

If you’re altering the firewall or transmission tunnel to accommodate a different bell housing or transmission on vehicles with a separate chassis, replacement sections must be fitted in the same manner as the removed section – for example, screwed or bolted if originally fitted that way, or continuously seam welded if sheet metal was cut to remove the original panel.

A vehicle which has been classed as a Category A or B write off and received a Certificate of Destruction (CoD) cannot be reinstated or put back on the road. Only undamaged components can be salvaged and reused.

Examples of repairs and restorations for motorcycles

Repairs and restorations will include, but is not limited to the following:

• repairing damage or corrosion to a motorcycle frame
• replacing the forks

Repairs and restorations that affect the Vehicle Identification Number (VIN)

If the repair or restoration affects sight of the VIN, it will need to be re-stamped or attached to the replacement chassis, monocoque bodyshell or frame by a garage that provides this service.

To avoid losing entitlement to the original VIN, you must keep photographic evidence of the original VIN prior to the repair, should the identity of the vehicle be questioned at a later stage.

Replacing a vehicle’s chassis, monocoque bodyshell or frame (for motorcycles)

Where a chassis, monocoque bodyshell or frame for a motorcycle has been replaced like-for-like (for example, without changing the vehicle’s appearance or dimensions from its original manufacturer’s specification) this is classed as a repair, but it does need to be notified to DVLA using the form ‘Vehicle parts statement’ V627/1.

The replacement can be either brand new or second-hand but must be of the same specification as the original, although a non-galvanised chassis, monocoque bodyshell or frame can be replaced with a galvanised one.

We advise that the vehicle is presented for a voluntary MOT as a roadworthiness check after the chassis, monocoque bodyshell or frame (for motorcycles) replacement has been completed. Alternatively, a car or light goods vehicle can be presented for a voluntary Individual Vehicle Approval (IVA) inspection as a safety check following the replacement. You can find out more about voluntary approval.

If you’re using a second-hand replacement, evidence of the identity of the donor vehicle must be provided, this includes the V5C registration certificate (log book) for the donor vehicle, or official receipts from identifiable suppliers.

Where second-hand replacement parts are used to repair or restore a vehicle, these should be sourced carefully with only minor components being able to be taken from a vehicle which has been issued with a Certificate of Destruction (CoD). Major components from such a vehicle must not be used (see the section on major components).

You can find out more about scrapped and written off vehicles.

Once your application is processed, we will provide authorisation for the part to be re-stamped with the VIN or frame number of the vehicle. This must be re-stamped next to or in the same area as the existing stamping.

Any existing identification number must be partially obliterated by stamping a series of ‘—– ’ characters.

If there is no existing stamping, the VIN should be stamped on the right-hand side of the vehicle in a clearly visible and accessible position, in a way that it cannot deteriorate or be destroyed.

Once confirmation that the original VIN has been re-stamped, we will issue a new V5C registration certificate (log book) which will include a marker in the ‘Special Notes’ section.

Structural modifications

Vehicles that have been structurally modified from their original specification

You must notify DVLA when a vehicle has undergone a structural modification. This must be done using the form ‘Modified vehicle statement’ (V627/3). An MOT may be required - see the MOT requirements for modifications.

This work should only be carried out by a person with the relevant engineering knowledge to carry out a modification safely. It’s also recommended that you contact your vehicle insurance provider to check whether the changes affect the motor insurance cover.

Definition of a structural modification

A structural modification will include cutting into a vehicle’s chassis (in the case of a vehicle with a separate chassis), monocoque bodyshell (in the case of a monocoque vehicle) or frame (for motorcycles) and changing a vehicle’s appearance or dimensions from its original manufacturer’s specification.

It’s 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.

Component definitions

Chassis: the load-bearing framework of a motor vehicle that is constructed with a separate non-load bearing bodyshell. Typically, it takes the form of a ladder-like frame upon which the body, powertrain and suspension are mounted.

Monocoque bodyshell: a type of vehicle construction where the body and chassis are integrated into a single, cohesive structure.

Motorcycle frame: a vehicle’s core structure and supports the engine and other components as well as the rider, passenger, and luggage.

Examples of structural modification for cars and light goods vehicles (under 3,500kg)

A structural modification will include, but is not limited to the following:

• lengthening, shortening, or widening a vehicle’s chassis or monocoque bodyshell to accommodate a different shape or style of bodyshell or resemble a different type of vehicle (for example, changing a vehicle’s specification or appearance from a coupe to a roadster or changing the appearance of a car or van to resemble a pickup)
• cutting one or more roof pillars and lengthening or shortening them
• removing the roof
• removing an integrated roll cage, (for example, incorporated into the roof pillars as part of a vehicle’s original specification)
• modifying the design of load-bearing sub-frames or support members
• removing load-bearing sub-frames or support members
• making any additional holes within 30cm from any suspension, steering, braking, or seatbelt mounting point
• motorcycle to tricycle modification*
• conversion to electric propulsion**
• sidecar welded to motorcycle***
• alterations to the firewall or transmission tunnel to accommodate a different bell housing or transmission (for monocoque vehicles only)

If you’re altering the firewall or transmission tunnel to accommodate a different bell housing or transmission on vehicles with a separate chassis, replacement sections must be fitted in the same manner as the removed section – for example, screwed or bolted if originally fitted that way, or continuously seam welded if sheet metal was cut to remove the original panel.

Examples of structural modification for motorcycles

A structural modification will include, but is not limited to, any lengthening, shortening, or widening of a vehicle’s frame or changing its appearance.

*Motorcycle to tricycle modification

Where a motorcycle to tricycle conversion has been carried out using a conversion kit or plans, these will be assessed in accordance with the kit-conversion guidance. See the section on kit conversions.

Where a motorcycle has been converted to a tricycle without using a conversion kit or plans, this is classed as a modification. Note that:

• where the tricycle system has been welded onto a vehicle, a DVLA VIN will be allocated, and the vehicle will be required to undergo Motorcycle Single Vehicle Approval (MSVA) before it can be used on public roads
• where the tricycle system has been bolted onto a vehicle, MSVA is not required

**Vehicles converted to electric propulsion

Converting a vehicle with an internal combustion engine to electric propulsion must only be undertaken by a specialist with the electrical engineering knowledge necessary to carry out a conversion safely.

The process of converting a vehicle from an internal combustion engine to electric propulsion is considered a modification. This is because it requires the engine and transmission to be removed and significant modifications to key vehicle control systems, including braking and steering assistance, as well as changes to accommodate an electric motor and battery pack.

There is a legal requirement to notify DVLA of a change of fuel type as this may affect the information shown on the V5C. This must include full details of the modifications that have been done to the vehicle as part of the conversion to electric. The MOT requirements (over or under 40 years old) are also applicable for electric conversions.

Where the law allows, DVLA will amend the fuel type and tax class to electric.

Cars and light goods vehicles first registered on or after 1 March 2001 are taxed according to the CO2 emission figure. When a vehicle has been converted to electric propulsion, the law requires DVLA to retain the CO2 emissions figure recorded at first registration. This means the vehicle must remain in a CO2 based tax class and cannot be moved into the electric tax class.

***Motorcycle with welded on sidecar

Attachment of a sidecar to a motorcycle through welding is classed as a modification and must be notified to DVLA.

Where a sidecar has been welded onto a vehicle, a DVLA VIN will be allocated, and the vehicle will be required to undergo Motorcycle Single Vehicle Approval (MSVA), before it can be used on public roads.

MOT requirements for modifications

Vehicles over 40 years old:

To submit a modification for vehicles over 40 years old, you will need to provide an MOT.

The requirement to present an MOT with your notification is applicable to all modifications including motorcycle to tricycle and electric conversion.

Vehicles under 40 years old:

We advise that you consider presenting the vehicle for a voluntary MOT as a roadworthiness check after the modifications have been completed. Alternatively, a car or van can be presented for a voluntary Individual Vehicle Approval inspection (IVA) as a safety check of the modifications.

Find out more information about the MOT requirements for vehicles that have been substantially changed.

Motorcycle to tricycle modification:

We advise that you consider presenting the vehicle for a voluntary MOT as a roadworthiness check after the modifications have been completed.

If the vehicle is over 3 years old, as the MOT class will be affected by this type of conversion, you will be legally required to obtain an MOT in the correct class. This must be provided as part of your notification to DVLA. This includes a vehicle that is over 40 years old and previously exempt from MOT.

DVLA vehicle identification numbers and Q registration numbers

Where there is a question over the identity of a vehicle, DVLA may require the vehicle to be inspected.

Where the identity or age of a vehicle cannot be determined, a vehicle may require re-registration with a DVLA VIN, IVA/MSVA and a Q registration number.

If you are considering buying a vehicle without a VIN or registration number, you should beware. If the police suspect that the vehicle has been stolen, you may lose it and the money you paid for it. You should check you’re not buying a stolen or unsafe vehicle.

‘Q’ and ‘QNI’ registration numbers are issued where the age or identity of the vehicle is not known. The display of a ‘Q’ or ‘QNI’ registration number is a visible sign to a prospective purchaser that the age or identity of the vehicle is in doubt. The vehicle must have IVA or MSVA before a ‘Q’ or ‘QNI’ registration number can be used.

The level of type approval and type of test required will depend on the vehicle. If your vehicle cannot be tested or it is unable to pass the test, DVLA will not register it. Further information on type approval is available online, from the Driver and Vehicle Standards Agency (DVSA) on 0300 123 9000, or from the Driver and Vehicle Agency (DVA) on 0300 200 7862.

Vehicle identity:

The inability to determine the identity of a vehicle could occur (but is not limited to) when:

• a vehicle is presented for registration without its original registration documents and where a club is unable to accurately date a vehicle
• a vehicle is not displaying a VIN or chassis number or has been modified to an extent that the VIN cannot be identified
• the VIN or chassis number has been lost and valid evidence to confirm its identity cannot be provided
• a VIN appears to have been tampered with
• more than one vehicle is claiming the same identity
• a vehicle is not presented for a requested inspection
• the results of an inspection do not confirm the identity of the vehicle or identifies further concerns regarding the identity of the vehicle or its components
• if the specific identity of the vehicle cannot be determined (providing the year of manufacture can be evidenced, an age-related registration number may be assigned to a vehicle)

It’s the vehicle keeper’s responsibility to provide enough reliable evidence to prove the vehicle’s identity so it can keep its original VIN and registration. Keepers should try to gather as much evidence as possible about any work carried out throughout the vehicle’s life.

There are additional sources for supporting documentation and evidence.

If the vehicle was registered with local authorities prior to 1974 – you may wish to seek out local archived information.

If the manufacturer of the vehicle is still in existence – you may wish to contact them.

You can find a list of vehicle owners clubs which may offer services to help you evidence the identity or age of a vehicle.

Any costs incurred are the responsibility of the vehicle keeper and will not be reimbursed by DVLA.

Inspection request

As part of our assessment of your application and before we can consider issuing a V5C registration certificate (log book), your vehicle may need to be examined so that we can:

• verify the information provided in your application
• supplement the information already provided by you
• verify the identification details on the vehicle against the vehicle record
• verify the existence and particulars of the vehicle

You will be contacted if this applies. The examination report, along with the information you have already provided, will support our assessment and help determine the outcome of your application.

Making your notification

To notify DVLA that you’re replacing a vehicle’s chassis, monocoque bodyshell or frame (for motorcycles), you will need the current V5C registration certificate or a completed ‘Application for a vehicle registration certificate’ (V62).

You will need photographic evidence for the vehicle receiving the replacement chassis, monocoque bodyshell or frame (recipient vehicle) showing:

• the whole vehicle, including front, back, sides, interior and the registration number plate
• the stamped-in VIN or chassis number of the existing chassis, monocoque bodyshell, or frame (the one that is being replaced)
• VIN sticker if available (usually located in the door shut), of the existing chassis, monocoque bodyshell, or frame (the one that is being replaced)
• VIN plate and its location on the vehicle of the existing chassis, monocoque bodyshell, or frame (the one that is being replaced)
• the engine number of the existing vehicle

You will need a completed ‘Vehicle parts statement’ V627/1, providing full details of the replacement chassis, monocoque bodyshell or frame.

You will need support and confirmation of specification (reconstructed classics) from an appropriate owners club.

Evidence for the replacement chassis, monocoque bodyshell, or frame must include either a copy of the receipt or invoice from the supplier which evidences its specification or the latest V5C registration certificate (log book) for this vehicle, if the replacement is taken from a registered vehicle.

Structural modifications:

Include the following supporting documentation for a modification notification:

• a completed ‘Modified vehicle statement’ V627/3, including the vehicle registration number and full details of the modifications that have been done to the vehicle
• the vehicle’s current V5C
• evidence of a current MOT (if required)
• supporting evidence from an owners club (if required)
• an MSVA – for motorcycle to tricycle modifications where the attachment has been welded on
• photographic evidence of the changes made to the vehicle

What happens next

Providing there are no concerns over a vehicle’s identity, a structurally modified vehicle will keep its original VIN and registration number. A new V5C will be issued to reflect any changes to the vehicle details.

An explanation will also be included in the ‘Special Notes’ section of the V5C that the vehicle has been modified from its original manufacturer’s specification or has had a like-for-like notifiable chassis, monocoque bodyshell or frame replacement. Examples of the special notes are as follows:

• ‘Rebuilt’ – assembled from parts some or all of which were not new
• ‘Modified’ – the original chassis, monocoque or frame has been modified from the manufacturer’s original specification*
• ‘Electric conversion’ – the original combustion engine has been replaced by an electric motor and battery*

*These new markers will be available in the future, but for now, the current ‘Rebuilt’ marker will still be used because it effectively shows that changes have been made to the vehicle. Once the new markers are available, they will be applied to any applications processed after that date.

Part 2 – kit-builds, kit-conversions and reconstructed vehicles

Kit-built vehicles

If all the parts of a vehicle are supplied new by the manufacturer, the vehicle will be allocated a current registration number as long as satisfactory receipts and a certificate of newness are provided.

Kit cars which have been built using no more than one reconditioned component will also be registered under a current registration number, as long as satisfactory evidence that the component has been reconditioned to an ‘as new’ standard has been provided. The vehicle must have IVA or MSVA.

Kit-conversions

This is where a kit of new parts is added to an existing vehicle, or old parts are added to a kit of a manufactured body, chassis or monocoque bodyshell. The general appearance of the vehicle will change and result in a different description being put on the V5C registration certificate (log book).

A vehicle will keep the registration number of the original vehicle if the original unaltered chassis or monocoque bodyshell has been used along with 2 other major components from the original vehicle.

If a new monocoque bodyshell or chassis from a specialist kit manufacturer (or an altered chassis or bodyshell from an existing vehicle) is used with 2 original major components from the donor vehicle, a replacement registration number will be issued based on the age of the donor vehicle. The vehicle must have IVA or MSVA. The date of manufacture for the vehicle will be taken from the IVA or MSVA certificate.

Where insufficient parts from a donor vehicle are used or in cases where the original registration is unknown, IVA or MSVA will be required to register the vehicle and a ‘Q’ or ‘QNI’ registration number will be allocated.

Major components for cars and light vans

There are 6 major components that are used by DVLA when assessing changes made to cars and light vans. These are the:

• chassis (ladder or running chassis) or monocoque bodyshell
• engine or electric motor
• transmission
• steering assembly
• axles
• suspension

Major components for motorcycles and tricycles

There are 4 major components that are used by DVLA when assessing changes made to motorcycles and tricycles. These are the:

• frame
• engine and gearbox
• wheels
• forks

Reconstructed classics

Historic vehicles reconstructed using genuine period components

The reconstructed classic registration scheme supports the restoration of unregistered vehicles over 40 years old.

The major components used to reconstruct a vehicle must be over 40 years old but not necessarily from a single vehicle.

These must be genuine period components and of the same specification and from the same period as when a vehicle was in production. This includes the chassis, monocoque or frame.

Where a vehicle has been reconstructed using period major components, providing an appropriate owners club are willing to support the vehicle as being a true representation of a marque and date the vehicle, it can be registered with an age-related registration number.

A DVLA VIN must be allocated, as any original chassis, VIN or frame number cannot be used as there cannot be a link to another vehicle.

In all instances an appropriate owners club must inspect a vehicle and support the vehicle as being a true reflection of a marque, and date the major components used. This is critical as the vehicle will be registered with an age-related registration number which is assigned based on the age of the newest major component.

Where a mixture of period and non-period components (except for a non-period replacement body) are used, an age-related registration number cannot be assigned, and a vehicle will require type approval before it can be registered with a ‘Q’ registration number.

In all instances the rebuild marker is added to the record, and for pre-1963 dated vehicles the non-transferable marker is also set.

A current MOT is required at the point of registration.

Vehicles supported by an owners club and dated as being over 40 years old will qualify for the historic tax and MOT exemptions.

Unregistered vehicles under 40 years old that have been restored or reconstructed can still be registered, but not under the reconstructed classic scheme. Where required, an appropriate owners club would need to accurately date the vehicle. Where a vehicle does not have a VIN, a DVLA VIN will be allocated.

Separate chassis/bodyshell construction vehicles

For vehicles with a separate chassis/bodyshell construction, where the original body that would have been fitted is beyond repair and an original period replacement body is not available, a newly built replacement body can be used to reconstruct a vehicle.

The owners club will need to confirm that the replacement body is the same specification as it would have been when a vehicle was in production. This will not affect the allocation of an age-related registration number, which will be assigned based on the other newest period major component.

Alternatively, an original interchangeable body can also be used where the owners club advise this was originally available as an option by the manufacturer and does not involve any modifications being made to the chassis. For example, if a 4-door body is replaced by a 2-door.

Specials:

These are separate chassis/bodyshell vehicles, reconstructed using a 1930s chassis and running gear with 1950s or 1960s fibreglass or aluminium bodywork.

Providing the appropriate owners club are able to support a vehicle as being a genuine known example of a ‘Special’ from this era, the vehicle will be registered based on the age of the newest major component, for example, the replacement different-style body.

Making your application

Include the following supporting documentation with your application:

• form ‘Application for first vehicle tax and registration of a new motor vehicle’ (V55/4) (for new kit-built vehicles) or form ‘Application for first vehicle tax and registration of a used motor vehicle’ (V55/5)
• vehicle tax (where appropriate)
• form ‘Vehicle parts statement’ (V627/1)
• IVA/MSVA certificate (if required)
• MOT certificate (if required)
• insurance certificate for vehicles registered with a Northern Ireland address (downloaded copies are acceptable, photocopies are not)
• certificate of newness (kit vehicles)
• registration fee (if required)
• receipts – these must show detail of the component (any identification or serial number shown), its specification and provenance - you must provide official receipts or an invoice(copies of either are acceptable) from identifiable suppliers for the major components used in the build
• V5C registration certificate (log book) if a donor vehicle is used
• confirmation of ‘Notification of Vehicle Arrival’ (NOVA) if applicable - see more information at ‘Importing vehicles into the UK’
• documentation confirming your name and address – see the information below

Send a photocopy of your UK photocard driving licence with your application form to prove your identity. Do not send the original.

If you cannot do this, you must send in photocopies of one document that proves your name and another document that proves your address.

Documents we will accept to confirm your name are your:

• passport
• marriage or civil partnership certificate
• divorce or end of civil partnership document (decree nisi, decree absolute, conditional order or final order)
• birth certificate or adoption certificate
• gender recognition certificate

Documents we will accept to confirm your address are a:

• gas, electricity, water or landline phone bill issued in the last 3 months
• council tax bill for the current year
• bank or building society statement issued in the last 3 months
• medical card or letter

What happens next

Kit-built vehicles – a current registration number is allocated to a kit-built vehicle that uses no more than one reconditioned component. If the vehicle has more than one reconditioned component, a ‘Q’ registration number will be allocated.

Kit-converted vehicles – dependent on the parts used, a kit-converted vehicle can be assigned the original registration number, an age-related registration number or ‘Q’ VRN.

Reconstructed classic vehicles will be assigned an age-related registration number. Where a vehicle has been reconstructed with a mixture of new and used parts, a ‘Q’ registration number will be allocated.

An explanation will also be included in the ‘Special Notes’ section of the V5C. Examples of the special notes are as follows:

• ‘Rebuilt’ – assembled from parts some or all of which were not new
• ‘Kit-built converted’ – assembled from parts all of which may not be new

Where to send your application

You must send your application and supporting documents to the address below:

Kits and Rebuilds
D10
DVLA
Swansea
SA99 1ZZ