What questions should I ask a car dealer when buying a used car?

Ask seven things: the MOT history and its advisories; the service record with invoices; whether finance is outstanding; the V5C and the number of former keepers; the annual vehicle tax and the list price when new; ULEZ and Clean Air Zone compliance; and the warranty terms in writing. Each protects against a specific, documented risk.

The seven questions

Each one exists to close a specific gap between what a listing shows and what you would find out later. Ask them in this order: the first four decide whether to keep looking at the car at all, and the last three decide what owning it costs and what happens if it goes wrong.

1. Can I see the full MOT history, and will you talk me through the advisories on it?
2. Is the service history documented, and can I see the invoices rather than just the stamps?
3. Is there any outstanding finance on this car, and will you give me written evidence it has been settled?
4. Can I see the V5C, is it in the dealership’s name, and how many former keepers are recorded?
5. What is the annual vehicle tax on this car, and what was its list price when new?
6. Does this car meet the ULEZ and Clean Air Zone standards for where I live and drive?
7. What warranty is included, for how long, what is excluded, and can I have it in writing?

Condition: the MOT history, and the advisories written on it

Ask: Can I see the full MOT history, and will you talk me through the advisories on it?

Why it matters. DVSA grades every defect found at a test Minor, Major or Dangerous, and a Minor defect still passes. Only Major and Dangerous defects fail, and DVSA defines a Dangerous defect as one presenting a direct and immediate risk to road safety or an impact on the environment. An advisory is not on that scale at all: it is a note about something not judged a defect. A certificate can therefore list both advisories and Minor defects and still be a clean pass, which is why a dealer saying the car passed has told you almost nothing.

The scale of what a test finds is worth knowing before you read one. In 2024/25 DVSA recorded 35,229,047 tests in Great Britain across all vehicle classes. Within classes 3 and 4, which cover cars, the initial failure rate was 28.08% at an average of 2.44 defects per initial failure, and at least one dangerous defect was found in 7.70% of tests. Lamps, reflectors and electrical equipment were recorded against 10.89% of all tests and made up 25.01% of all defects, so they dominate on volume. Severity sits elsewhere.

Source: DVSA MOT testing data 2024/25, classes 3 and 4, Great Britain. A tyre advisory is a note about the component most often found in a dangerous condition, on a part that goes on wearing with every mile.

How to close the gap yourself. The public MOT history service publishes every past result, the advisories written at each test and the mileage recorded on the day. It goes back to 2005 in England, Scotland and Wales, and only to 2017 in Northern Ireland, where testing is carried out by the DVA rather than DVSA. Reading several years in sequence tells you more than the latest certificate: an advisory repeated at four consecutive tests and never resolved describes a maintenance habit, and one that disappears suggests the work was done. Our MOT check tool works out when the next test falls due.

The dates and fees differ across the border. The first MOT falls on the third anniversary of registration in Great Britain and at four years in Northern Ireland. The maximum fee for a class 4 vehicle is £54.85 in Great Britain, and a garage may charge less; in Northern Ireland the DVA charges £38.00 for a full test and £29.50 for a retest. Those figures are maximums, they are free of VAT, and they have been unchanged since 2010.

Upkeep: the service history, and what a stamp actually proves

Ask: Is the service history documented, and can I see the invoices rather than just the stamps?

Why it matters. A stamp proves a book was stamped. An invoice names the garage, the date, the mileage on the day and the work carried out, which is the only version of a service history that can be checked against anything. There is no statutory service record and no register a buyer can consult, so this is the one item on the list where the paperwork the dealer holds is the whole of the evidence. Ask to see it before you agree a price, not after.

The free cross-check is the MOT history, because it publishes the mileage recorded at each test. Line those readings up against the service invoices and against the odometer in front of you. Gaps, reversals and jumps are visible in a minute, and a service invoice dated between two tests should sit sensibly between their two readings.

Source: Department for Transport National Travel Survey, England 2024. These are self-estimated survey averages across a population of drivers, not a standard any individual car is expected to match, and they cover England rather than the whole United Kingdom. Use them only to notice a history that is wildly out of line with the way the car was described. For context, DfT records the average licensed car in the United Kingdom as 10 years old, out of 42.3 million licensed vehicles.

Title: outstanding finance, the V5C and the number of former keepers

Ask: Is there any outstanding finance on this car, and will you give me written evidence it has been settled? And: Can I see the V5C, is it in the dealership’s name, and how many former keepers are recorded?

Why it matters. Under a hire purchase or PCP agreement the finance company owns the vehicle until the agreement ends. The Consumer Credit Act 1974 s.189(1) defines the total price as including the sum payable on exercising the option to purchase — the balloon payment on a PCP — which is the point at which ownership passes. A car still subject to an agreement is therefore not the seller's outright to sell, and the answer to give weight to is the written settlement evidence, not the reassurance. A finance check against the registration is how you confirm the position rather than take it on trust.

The V5C is a registration document, not a title deed: it records the registered keeper, which need not be the legal owner, and it carries the number of former keepers. Check that the details on it match the car in front of you and that a dealer selling in the trade can explain why the document is in whichever name it is in. Ask when you can expect the new document, and remember that the number of former keepers is a fact you can only get from the V5C or a history check — it is not on the car.

The registration also tells you the age. The age identifier in a number plate follows a fixed cycle: 26 covers March to August 2026, 76 covers September 2026 to February 2027, 27 covers March to August 2027 and 77 covers September 2027 to February 2028. Misrepresenting a vehicle's age with a registration is treated seriously: it risks a fine of up to £1,000, failure of the MOT and permanent withdrawal of the registration.

Running cost: vehicle tax and the registration regime the car falls in

Ask: What is the annual vehicle tax on this car, and what was its list price when new?

Why it matters. What a car costs to tax is decided by the date it was first registered, not by what you pay for it, and there are three regimes. The newest covers cars first registered on or after 1 April 2017: £200/year standard rate from the second year, hybrids included — the alternative-fuel discount ended on 1 April 2025. Cars registered 2001–2017 pay a CO2 band, roughly £20–£790/year (2026/27 rates). Cars registered before 1 March 2001 are taxed on engine size alone: £230 a year up to 1549cc and £375 above it. Our car tax calculator works the figure out from the registration date and emissions.

The list price when new is the part a listing cannot tell you. For cars first registered on or after 1 April 2017 the Expensive Car Supplement adds £440 a year in years two to six, and it is triggered by the list price when the car was new — £40,000 for petrol, diesel and alternative-fuel cars, and £50,000 for zero-emission cars first registered on or after 1 April 2025, a threshold that took effect on 1 April 2026. A used listing shows the asking price, which says nothing about the list price years earlier, so this is a question rather than a calculation.

• Electric cars registered 1 April 2017 to 31 March 2025 pay the £200 standard rate and no Expensive Car Supplement, whatever the list price was.
• The zero-emission first-year rate is £10 from 1 April 2026, and it is paid once, by whoever registers the car new.
• The tax does not come with the car. It is cancelled on a change of keeper anywhere in the United Kingdom and any full remaining months are refunded to the seller. You have to tax the vehicle before you drive it, or declare it off the road with a SORN. The guide to vehicle tax when buying a used car sets out what happens at the handover.
• The historic tax exemption is separate from the testing one. A vehicle built before 1 January 1986 is exempt from 1 April 2026, but the exemption has to be applied for and the vehicle still has to be taxed, at a zero rate.

Where you can drive it: ULEZ and Clean Air Zone compliance

Ask: Does this car meet the ULEZ and Clean Air Zone standards for where I live and drive?

Why it matters. Compliance is defined by Euro emissions standard, not by age: Euro 4 for petrol, typically 2006 onwards, and Euro 6 for diesel, roughly September 2015 onwards. The standard is set per model at type approval and some models met it early, so a year is a guide and the registration itself has to be checked. London's ULEZ charges a non-compliant car £12.50 a day, every day except Christmas Day, across all London boroughs. Vehicles built before 1 January 1973 and vehicles in the DVLA historic tax class are exempt, and the grace period for the disabled tax class runs to 24 October 2027.

Outside London the map is narrower than most people assume. England has seven Clean Air Zones, and only a Class D zone includes private cars, so only Bristol (£9 a day) and Birmingham (£8 a day) charge them. Bath, Bradford, Sheffield, Newcastle & Gateshead and Portsmouth do not charge private cars at all, whatever their age or fuel. Greater Manchester has no charging zone.

One place charges cars without being a Clean Air Zone at all, so a dealer answering only on Clean Air Zones can be right and still leave you exposed. The Oxford Zero Emission Zone sits outside the scheme, covers a small set of central Oxford streets (pilot zone) and operates 7am–7pm, seven days a week, year round. It charges in emissions bands rather than on a pass-or-fail standard, so a car that clears every Clean Air Zone in England still pays £4 a day there while a zero-emission car pays nothing. The answer on ULEZ and zone charges sets out the full band table.

Scotland works on a different principle again. Low Emission Zones operate in Glasgow, in force from 1 June 2023 with residents brought in on 1 June 2024, Dundee from 30 May 2024, and Edinburgh and Aberdeen from 1 June 2024. There is no daily charge you can choose to pay: a penalty starts at £60, doubles on each further contravention, is capped at £480 for a car, is reduced by 50% if paid within 14 days and resets after 90 clear days. Northern Ireland has no ULEZ, Clean Air Zone or Low Emission Zone at all, so none of this applies there. Our clean air zone checker shows which zones a car would be charged in.

Recourse: the warranty in writing, and the rights you have without one

Ask: What warranty is included, for how long, what is excluded, and can I have it in writing?

Why it matters. A warranty is a contract term the dealer chooses to offer, so its length, its exclusions and its claims process are whatever the document says — which is the reason to read the document rather than accept a duration. Underneath it sit the statutory rights that come from buying from a trader. The Consumer Rights Act 2015 gives a 30-day short-term right to reject, and a fault appearing within the first six months is presumed to have been present at delivery. Cars are treated differently in one specific respect: section 24(10) permits a deduction for use even inside the first six months, and it applies precisely because the goods are a motor vehicle.

If the purchase is financed, ask who you would be claiming against. Section 75 of the Consumer Credit Act 1974 does not reach dealer-arranged hire purchase or PCP, because it requires an agreement within s.12(b) or (c) and there the creditor is also the supplier; its limits in any case run from £100 to £30,000. The routes that do work are s.56(2) of the same Act, under which the dealer negotiates as agent of the finance company so its statements bind the lender, and section 7 of the Consumer Rights Act 2015, under which hire purchase is a goods contract and a satisfactory-quality claim lies against the finance company that owns the car. The section 75 guide sets out both routes, and the voluntary termination guide covers the separate right to end an agreement early. The PCP calculator shows how an agreement is structured.

One further question is worth asking: whether the dealer is accredited to The Motor Ombudsman. It is free to consumers, its decisions bind the business if the consumer accepts them, it is approved by the Chartered Trading Standards Institute, and its Vehicle Sales Code was approved in October 2016. An accredited dealer has agreed in advance to a route that does not involve a court.

Extra questions for an older car, and for an electric one

• Is it exempt from testing, and why? In Great Britain a vehicle built or first registered more than 40 years ago, with no substantial changes in the last 30, is exempt from the MOT. The exemption is automatic and declared on form V112. It does not cover substantially changed vehicles, Q-plated vehicles, kit cars, kit conversions or DVLA-defined reconstructed classics, and it is a different thing from the historic tax exemption described above. That is the Great Britain rule: Northern Ireland vehicles are tested by the DVA under its own rules, so any exemption there has to be confirmed with the DVA rather than read across from this one.
• Is it compatible with E10 petrol? E10 has been the standard petrol grade in Great Britain since September 2021 and in Northern Ireland since November 2022. All new cars made since 2011 are compatible, so the question only arises on an older petrol car.
• If it is electric, what is the battery state of health and how was it measured? Ask for the reading, the date and the method, in the same way you would ask for a service invoice rather than a stamp. Where you would charge it matters as much as the car: our guide to charging costs and the charging cost calculator set out the difference between charging at home and charging in public.

The seven questions at a glance

Related pages

• MOT check — when the next test falls due.
• Car tax calculator — the annual figure from the registration date and emissions.
• Clean air zone checker — which zones would charge a given car.
• Vehicle tax when buying a used car — what happens to the tax at a change of keeper.
• Section 75 and car finance — who a claim actually lies against.
• Most reliable used cars in the UK
• Car buying glossary — the terms that appear on a V5C, an invoice and a finance agreement.
• Is my car exempt from the MOT? — the testing exemption in full.
• What are my rights if a used car breaks down? — what the Consumer Rights Act gives you after the sale.
• Will my car be charged in the ULEZ? — every charging zone, including Oxford's.
• Compare cars side by side

Sources: DVSA MOT testing data 2024/25 (classes 3 and 4 unless stated) and published maximum test fees; DVLA vehicle tax rate tables for 2026/27; Transport for London and local authority clean air zone charges; Department for Transport National Travel Survey, England 2024, and vehicle licensing statistics; the Consumer Rights Act 2015 and the Consumer Credit Act 1974. Verified 9 September 2026. Rules described as applying to Great Britain are stated for Great Britain only: Northern Ireland vehicles are tested by the DVA under its own rules and fees, and Northern Ireland has no ULEZ, Clean Air Zone or Low Emission Zone.