This is not a rare crime
We ran the odometer sequence of every vehicle in Britain's MOT record, 2022 to 2024. The result: 293,317 cars whose recorded mileage went backwards between tests, and another 16,566 with jumps too big to believe. That's 309,883 vehicles, about one in every 112 with enough history to check, and it doesn't count cars clocked before their first MOT at age three, which no database on earth can see. The full analysis breaks it down by age and make.
The maths of why is simple: knock 40,000 miles off a family car and you add roughly £2,000 to £4,000 to its price. The tool costs about £100. Enforcement is thin. So assume the car you're viewing might be one of them, and check.
Check one: the MOT mileage trail (free, two minutes)
Every MOT since 2005 logs the odometer, and that history is public. Run the reg through our MOT check and read the mileage chart: it should climb steadily, roughly 5,000 to 10,000 miles a year for a normal car. What you're looking for:
The government's own MOT history service shows the same readings raw; ours draws the chart and flags the anomalies for you.
Check two: does the wear match the miles?
A 40,000-mile car should look like one. Sit in it and audit honestly: a steering wheel worn shiny, a driver's seat bolster collapsed, brake and clutch pedals polished down to metal, a gear knob rubbed smooth. Any one of those on a "low mileage" car is a conversation; two or more is a verdict. Check the service stickers inside the door or under the bonnet too: garages write the mileage on them, and sellers forget to remove old ones.
Check three: the paper trail
Ask for the service history and read the mileages through it in order, invoices included: they should march upward in step with the MOT record. Then ask the seller, casually, roughly how many miles a year the car has done. Someone selling an honest car answers instantly. Someone selling 12,000 miles a year as 4,000 does arithmetic in their head first, and you can watch it happen.
Common questions
What does clocking a car mean?
Winding back the odometer so a car shows fewer miles than it has really done. Digital dashboards made it easier, not harder: a £100 tool off the internet can do it in minutes.
How common are clocked cars in the UK?
Our analysis of every MOT test from 2022 to 2024 found 309,883 vehicles whose recorded mileage either fell between tests or jumped implausibly: roughly one in every 112 cars with enough history to check.
Is clocking illegal?
Selling a clocked car without declaring it is fraud. Owning the tool and altering your own odometer is not in itself illegal, which is exactly why the practice survives.
Can a clocked car be fixed?
The mileage can be corrected on paper if the true figure can be proven, but the real damage is mechanical: the car has worn parts its service schedule never accounted for.
Does a HPI or history check show clocking?
Paid checks compare recorded mileages from several databases and flag discrepancies, and our free mileage check does the same with every MOT odometer reading. Neither can catch a car clocked before its very first MOT.