An American classic in the UK can be exempt from MOT testing if it was built or first registered more than 40 years ago and has had no substantial changes, and it can be exempt from vehicle tax if it was built before 1 January 1986, but you must apply for the tax exemption and the car must always stay roadworthy.
Rules like these can change, so always check the current wording on GOV.UK before relying on anything below. This guide is general information, not legal advice. The official page is GOV.UK: Historic (classic) vehicles, MOT and vehicle tax.
The MOT exemption: the 40-year rule
Under GOV.UK’s guidance, a vehicle can be exempt from MOT if it was built or first registered more than 40 years ago and it has not been substantially changed. You do not apply for MOT exemption in the same way as you do for tax, so there is no form to fill in. You simply need to be confident your vehicle meets the criteria.
What counts as a substantial change?
This is the part that catches people out. GOV.UK describes a substantial change as a change to the vehicle’s chassis, body, axles or engine that alters how the vehicle works. Swapping an engine for a different type, converting to a very different axle setup or rebuilding the body in a way that changes the car substantially could all be relevant. Routine repair or like-for-like replacement is a different matter, but the line is not always obvious, so read the official criteria and, if you are in doubt, treat the car as needing an MOT.
This matters for owners of American cars, because many have been upgraded over the years with uprated brakes, crate engines or different transmissions. If you are planning changes to a car you want to keep exempt, check the official criteria first. Our carburettor to fuel injection guide explains one common type of upgrade.
Exempt does not mean unchecked
A car without an MOT must still be roadworthy at all times. That means working brakes, safe tyres, steering and suspension in good order, and working lights. If it is used on the road in an unsafe condition, the owner can still face penalties. Many owners choose to have their classic tested voluntarily or checked regularly by a qualified person for peace of mind.
The vehicle tax exemption
Vehicle tax is separate. According to GOV.UK, vehicles built before 1 January 1986 (or registered before 8 January 1986 where the build date is not known) are exempt from vehicle tax from 1 April 2026. You still need to apply for the exemption, rather than assuming it happens automatically. Follow the GOV.UK process, and check the details for your own vehicle.
Importing a classic? Check the dates
For cars brought in from the USA, the date used for the rules can be tricky, because it depends on the build date or first registration date. The paperwork should be consistent. If you are buying a US classic, our classic American car buying checklist helps you ask the right questions.
Keeping a classic safe and sound
Older American cars often have drum brakes, older steering and simpler electrics. A little preventative maintenance goes a long way. Brakes are the first thing to look at, and our drum to disc brakes guide explains common upgrades. You can browse parts in our brakes and ignition categories. Brake and steering work should be done or checked by a qualified person.
What this means when you buy
- Check the build or first-registration date against GOV.UK’s current rules.
- Ask whether the engine, axles, chassis or body have been changed, and keep any records.
- If you buy a classic that is tax exempt, make sure the exemption has been applied for in the new owner’s name where required.
- Budget for a roadworthiness check even when a test is not required.
- Need help finding parts to keep it safe? Use our Source a part page.
Frequently asked questions
Does my American car need an MOT after 40 years?
Not necessarily. If it was built or first registered more than 40 years ago and has not been substantially changed, it can be exempt. If it has been substantially changed, the exemption may not apply. Check GOV.UK.
Do I have to apply for the MOT exemption?
GOV.UK says you do not apply for MOT exemption, but you do have to apply for the vehicle tax exemption. Check the current process on GOV.UK.
Is an exempt car allowed to be unroadworthy?
No. A car must be kept in a roadworthy condition whether or not it needs an MOT.
If you are looking for an American car, or want a mechanic’s eye on one you already own, talk to Oldcott Motors, selling American cars since 1958.