The MOT is one of those annual milestones that every car owner knows well. But when it comes to classics, the rules are a little different — and often confusing. Do you need an MOT if your car is over 40 years old? What happens if it’s been modified? And even if you’re exempt, is it wise to get one anyway?
Here’s your complete guide to classic car MOT rules and exemptions in the UK, and why keeping good records with Custodian matters.
What Is an MOT and Why Does It Matter?
The MOT (Ministry of Transport test) is an annual safety and roadworthiness check required for most vehicles over three years old. It covers brakes, lights, emissions, tyres, suspension, and more. Without a valid MOT, you can’t legally drive your car on public roads (except to a pre-booked test).
But for historic vehicles, there are special rules.
The 40-Year MOT Exemption Rule
According to GOV.UK guidance, you do not need an MOT if the vehicle was built or first registered more than 40 years ago and no ‘substantial changes’ have been made in the last 30 years, for example, replacing the chassis, body, axles or engine to change the way the vehicle works.
This mirrors the same 40-year rolling threshold used for the Historic Vehicle tax exemption. For example, in 2025, vehicles built before 1 January 1985 may qualify.
Important: You Must Declare Exemption When Taxing the Vehicle
If your vehicle is eligible, you declare MOT exemption when you apply to tax (re-license) it. As part of this process, you’ll be asked to confirm it has not been substantially changed. If you don’t make the declaration, the DVLA will still expect an MOT certificate.
What Counts as a “Substantial Change”?
The DVLA and DVSA define “substantial changes” in detail. Examples that would usually disqualify exemption include:
Routine maintenance or like-for-like restorations (engine rebuilds, panel replacement, suspension refresh) do not count as substantial changes. The same principle underpins the DVLA’s updated registration policy, which protects cars from unnecessary Q-plates.
For the full criteria, see the DVLA website here.
Why You Might Still Want an MOT
Even if you’re exempt, there are good reasons to continue with voluntary MOT tests:
Custodian: Keeping Your MOT Records Safe
MOT exemptions don’t mean you can skip record keeping. In fact, your digital history file is more important than ever. Custodian helps you:
Together, these records strengthen your car’s provenance.
Frequently Asked Questions
Do all cars over 40 years old automatically become MOT exempt?
No — you need to declare an exemption when you tax the vehicle.
If my car is exempt, can I still book an MOT?
Yes, you can voluntarily test your vehicle, which many owners do for peace of mind.
What if my classic is modified?
If it has been “substantially changed” in the last 30 years (e.g. engine swap, chassis mods), it may not be exempt.
Will being exempt affect my insurance?
Not directly, but many insurers view a valid MOT as evidence of condition. Check out our Guide to Classic Car Insurance for more.
Final Thoughts
The MOT exemption is one of the small perks of classic ownership in the UK, recognising that enthusiasts typically maintain their cars carefully and use them sparingly. But exemption doesn’t mean you can ignore roadworthiness — or the importance of paperwork.
By using Custodian to track your MOT status, exemption declarations, and service records, you’re not only protecting your car’s provenance, you’re also making life easier for yourself, insurers, and future owners.
Note: This guidance is correct as of September 2025. DVLA/DVSA decisions on exemptions and registrations are made case-by-case; if you’re unsure, consult the latest gov.uk historic vehicles guidance or a historic vehicle expert.
