How do I check a used car's history before I buy it?
What the free checks reveal, what only a paid history check will show, and what Category A, B, S and N actually mean when a car comes back as a write-off.
- Difficulty
- beginner
- Time
- 25 min
- Read
- 5 min
Short answer
Do the free checks first: the MOT history shows a decade of recorded mileages and advisories, and the DVLA enquiry confirms tax status and the car's declared specification. Then pay for a history check before you hand over money — outstanding finance, insurance write-off markers and stolen records only appear there, and outstanding finance means the car is not the seller's to sell.
A used car carries a documented past that is far easier to examine than most buyers realise, and the free half of it is genuinely revealing. The paid half exists because three specific facts are held by the finance and insurance industries rather than by government: whether money is still owed on the car, whether an insurer has written it off, and whether it has been reported stolen. Any of those can cost you the entire purchase price, which is why a history check is the cheapest insurance in the whole process.
Step by step
- Start with the MOT history, before you even view.Free, needs only the registration, and shows every test with the recorded mileage. Look for a steady mileage progression, repeated advisories that were never dealt with, and long gaps that suggest the car was off the road.
- Cross-check the advertised mileage against the record.If the advert says 60,000 and the car recorded 78,000 at its last MOT, walk away. Mileage discrepancies are the single most common problem the free check exposes.
- Check tax status and the declared specification.The DVLA enquiry confirms fuel type, engine size, colour and CO2 figure. A colour that does not match the car, or an engine size different from the advert, needs explaining before anything else happens.
- Pay for a history check before you commit.It is a modest sum from any of the established providers, and it covers outstanding finance, insurance write-off records, stolen markers, plate and colour changes, import or export records, and often a mileage check from additional sources.
- Take outstanding finance seriously.If a car is on finance, the finance company owns it. Buying it privately can mean the car is repossessed and you lose both the car and the money, with very limited recourse. Ask the seller to settle the finance and provide written confirmation, and do not accept assurances.
- Understand what the write-off categories mean.Category A means the whole vehicle must be crushed and nothing salvaged. Category B means the body shell must be destroyed although parts may be reused. Category S means structural damage that has been or can be repaired. Category N means non-structural damage. S and N replaced the older C and D in October 2017, and the change moved the definition from cost of repair to type of damage.
- Decide deliberately about a Cat S or N car.They can be legally repaired and sold, and they are cheaper for a reason. A properly repaired Cat N car may be a genuine bargain; a Cat S car has had structural damage, and how well it was repaired is not something you can assess by looking. Insurance can be harder and resale value is permanently reduced.
- Match the documents to the car.Check the V5C is in the seller's name at the address you are at, that the vehicle identification number on the V5C matches the one visible on the car, and that the V5C is not a replacement issued very recently, which can indicate an attempt to hide history.
- Keep the paperwork after you buy.The history check result, the MOT history at the time of purchase and the advert are worth keeping. If something was misrepresented, that evidence is what a claim rests on.
Common mistakes
- Doing the history check after paying a deposit — The point of the check is to inform the decision. Running it afterwards just tells you how much trouble you are already in.
- Relying on the seller's paperwork alone — Service books can be stamped by anyone and V5Cs can be replaced. The MOT history and a finance check are independent of the seller, which is precisely their value.
If it doesn't work
History check shows outstanding finance
Cause: The car is security for a loan — Fix: Do not buy until it is settled and you have written confirmation from the finance company, not from the seller. This is the single most expensive mistake in private car buying.
Car is a Cat N and the seller did not mention it
Cause: Non-disclosure — Fix: A private seller is not obliged to volunteer it but must not lie if asked; a trader must disclose it. Either way, it changes the value substantially and it tells you something about the seller.
V5C is in a different name from the seller
Cause: Selling on behalf of someone, or a trader posing as a private seller — Fix: Ask directly. Buying from someone who is not the registered keeper carries real risk, and a trader pretending to be private is avoiding your consumer rights — which is itself the warning.
MOT history shows the car failed repeatedly on the same item
Cause: Ongoing unresolved fault — Fix: Ask for the invoice showing the repair. Repeat failures on corrosion or structural items are particularly worth taking seriously.
Number plate has been changed
Cause: Personalised plate, or an attempt to break a history trail — Fix: A history check shows previous registrations. A plate change on an ordinary car with no obvious personalised plate is worth understanding.
Questions people ask
Is a paid history check really necessary?
For a private purchase, yes. Outstanding finance and write-off markers are not in any free service, and either can cost you the whole purchase price. It costs a tiny fraction of the car.
Should I avoid all write-off cars?
Not necessarily. A Cat N car with cosmetic damage properly repaired can be sound and good value. Category A and B cars should not be on the road at all. Cat S needs a much more cautious approach because the damage was structural, and an independent inspection is worth paying for.
What if I have already bought a car with finance on it?
Contact the finance company immediately and get advice. Your position depends on the details, including whether you bought in good faith and whether the sale was private or from a trade seller, and there is a specific protection for innocent private purchasers in some circumstances that is worth taking proper advice on.