Updated October 2026

Here’s the order most used-car buyers follow: fall in love with a car, travel to see it, maybe even haggle, then check its history. That’s backwards. The UK government publishes a remarkable amount of a car’s past for free, and you only need the registration number. Ten minutes of checks before you leave the house can save you a wasted journey, a bad purchase, or thousands of pounds. Here is everything you can find out for free, and what free checks honestly can’t tell you.

1. The MOT history check, the single most useful free check

Every MOT test carried out in Great Britain since 2005 is logged against the registration number, and the government lets anyone read it for free at gov.uk/check-mot-history. No account, no fee, no catch, just the number plate. If you’d like the same official data laid out with the warnings explained in plain English, CheckMyMOT’s free MOT history checker does exactly that.

What you get, year by year:

• Pass or fail for every test since 2005
• The mileage recorded at each test, the timeline that reveals clocking
• Every advisory note, issues the tester flagged but didn’t fail the car for
• Every failure reason, with major, dangerous and minor defects spelled out
• When the current MOT expires, so you know how much safe driving time you’re actually buying

This is the check that teaches you to read a car like a mechanic. Our MOT guide walks through the five patterns that matter most, but the short version is:

• Mileage that goes backwards between tests is a classic sign of clocking. A discrepancy isn’t automatic proof, it can be a recording error or a replacement instrument cluster, but it always deserves a hard question.
• The same advisory, year after year means the owner ignored a known problem. One advisory is wear; the same one three years running is neglect.
• Fail, fix, pass, all on the same day is usually just a garage retesting after a repair, but a car that failed on serious structural corrosion and passed hours later deserves a very careful look underneath.
• Repeated mentions of corrosion on brake pipes, subframes or suspension mounting points mean expensive work is coming, and on some cars, it means walking away.

Do this one before you do anything else. If the history looks bad, you’ve saved yourself a trip.

2. The DVLA vehicle tax and SORN check

The DVLA’s vehicle enquiry service, gov.uk/check-vehicle-tax, is also completely free and needs only the registration number. It tells you:

• Whether the car is currently taxed, and when the tax expires
• SORN status, whether the car is officially declared off the road
• When its MOT expires
• The car’s registered details: make, model, colour, engine size, fuel type, CO₂ emissions, date of first registration, year of manufacture and the date the last V5C logbook was issued

Why this matters when buying: vehicle tax does not transfer with the car. Even if the seller just taxed it, you’ll need to tax it yourself before you drive it away, and you can’t tax a car that doesn’t have a valid MOT or insurance. A SORN car, meanwhile, must not be driven or parked on a public road at all, so if you buy one, factor in that you’ll need to tax and insure it before it moves anywhere legally.

Also compare the registered details against the car in front of you. If the DVLA record says silver and you’re looking at a blue car, or the engine size doesn’t match, something is off, and you want to know that before money changes hands.

3. The ULEZ and Clean Air Zone check

If you drive in London, Birmingham, Bristol or any of the other charging zones, buying a non-compliant car can cost you a daily charge, £12.50 a day in London’s ULEZ (correct as of October 2026). The rule of thumb is that diesels need to be Euro 6 (roughly 2015 onwards) and petrols Euro 4 (roughly 2006 onwards), but “roughly” isn’t good enough when there’s a daily charge at stake, because some cars met the standards earlier than others.

Check any reg plate’s ULEZ and Clean Air Zone status for free before you buy. It takes seconds, and it’s one of the most commonly skipped checks in used-car buying.

4. The road tax (VED) cost check

Two identical-looking cars can cost wildly different amounts to tax. The expensive-car supplement alone adds hundreds of pounds per year for five years on cars that listed over £40,000 when new, and diesel vs petrol vs hybrid rates diverge sharply. Run the reg through a free VED calculator so the tax bill doesn’t ambush you after you’ve bought the car.

What free checks can’t tell you, and why it matters

Here’s the honest part. The free checks above cover the car’s condition, mileage timeline, tax and emissions. They do not cover the big legal risks:

• Outstanding finance. The DVLA doesn’t hold finance data, so no free check will show whether a lender has a registered interest in the car. If you buy a car with outstanding hire purchase or PCP finance, the finance company still legally owns it and can repossess it from you, even though you paid the seller in good faith.
• Insurance write-off status. A Category S or N car has been a total loss, repaired and returned to the road. It can be perfectly safe, but it must be declared, it should cost less, and you should know about it.
• Stolen markers. If the car is recorded as stolen, the police can seize it and return it to the rightful owner or insurer, and you’ll lose both the car and your money.

For those, you need a paid vehicle history check from providers such as HPI, Experian AutoCheck, the RAC or the AA. In 2026 these typically cost from around £3 for a basic finance-only search to about £20 for a full report covering finance, write-off status, stolen records and mileage. Against a car purchase, that’s one of the cheapest insurance policies you’ll ever buy.

The smart order is: run every free check first, for free, before you travel, then, only if the car passes all of those, pay for the history check before you hand over any money.

Your 10-minute pre-viewing routine

1. Enter the reg on gov.uk/check-mot-history (or CheckMyMOT’s free MOT history checker) and read the advisories and mileage timeline.
2. Run the DVLA check at gov.uk/check-vehicle-tax, tax, SORN, MOT expiry, and registered details vs the advert.
3. Check ULEZ and Clean Air Zone compliance.
4. Check what it’ll cost to tax with the VED calculator.
5. If all four look clean, pay for a finance/write-off/stolen history check.

Do all of that and you’ll walk into the viewing knowing more about the car than most sellers do.

Free first, paid only if you must

A used car is only as good as its history, and a surprising amount of that history is free in the UK: MOT results since 2005, tax and SORN status, emissions compliance, and the tax bill you’re signing up for. Run the free checks first, pay for the finance and write-off check second, and do all of it before you travel or hand over a penny. Ten minutes now beats ten thousand pounds of regret later.