Car clocking - what is it and how to avoid buying a clocked car
Cases of car clocking are on the rise, potentially leaving you out of pocket and at a higher risk of accidents. Here’s how you can avoid buying a used car with an altered mileage...
It’s all too easy to believe that the act of clocking cars died out when car manufacturers began fitting electric odometers in their models, preventing dodgy dealers and backstreet garages from reducing the mileage figure with a screwdriver.
Unfortunately, that couldn’t be further from the case. Digital odometers have made it easier than ever to clock a car, and as a result, cases are rising. According to data from the car diagnostics company Carly, 16.25% of used cars that were checked using their diagnostic tool in the UK between January and September 2025 had a mileage discrepancy. As a result, as many as one in seven used cars could be clocked.
Unknowingly buying a used car that has been clocked has a number of disadvantages, not least that you’d likely pay more than what the car would be worth. That extra mileage could mean you’ll be facing more repair bills, too.
There’s also growing concern surrounding consumer rights. In April 2025, the Chartered Trading Standards Institute (CTSI) warned that 52% of used car buyers within the past five years who encountered a fault were unable to resolve the matter with the seller, with nearly a quarter finding an issue with the service history or mileage. As such, some within the motor industry are pressuring the Government to address the rising tide of clocking after what they describe as many years of inaction.
However, it’s still possible to spot a used car that has been clocked before you buy it. Here, we share:
- The reasons why cases of car clocking are on the rise
- How mileage can affect a used car’s value
- The potential safety impact of car clocking
- Checks to avoid buying a clocked car
How does mileage affect value?
Traditionally, dodgy dealers would clock cars to increase their value on the second-hand market. The temptation to clock a car is clear: a five-year old Range Rover Sport that has covered 30,000 miles could fetch more than £11,000 more on a used car forecourt than the same car with 90,000 miles.
Below we look at how mileage affects the value of some popular five-year-old models.
Model with 30k miles with 60k miles with 90k miles
Audi A5 2.0 TDI 35 S Line £23,490 £20,990 £15,995
Sportback
Ford Fiesta 1.0T Trend £9800 £7995 £5990
Nissan Qashqai 1.3 Tekna £16,290 £12,300 £9500
Range Rover Sport 3.0 SD £37,500 £30,195 £25,995
V6 HSE Dynamic
Tesla Model 3 Dual Motor £19,495 £15,995 £13,995
Long Range
Volkswagen Golf 1.4 GTE £18,500 £14,995 £13,990
Why is clocking on the increase?
There are still instances of traders clocking cars on a massive scale. In January 2025, three men from Kent were given suspended sentences for clocking several vehicles, with an average mileage reduction of more than 90,000 miles.
However, one reason why car clocking might be on the rise is due to drivers, rather than traders. More than 80% of all new cars are financed in some way, with personal contract purchase (PCP) deals being the most common method. These deals help drivers spread the cost of a new car, but feature strict mileage restrictions during the term of the contract.
Since mileage has a big effect on the value of a car, which is owned by the finance company for the duration of the contract, drivers face a fine of between 3p and 30p per mile that exceeds the agreed limit. As a result, drivers who say they’re going to do 5000 miles per year during a three-year deal but end up covering twice the amount could face a fee of £1500.
The National Franchised Dealers Association (NFDA) also cites the lack of official recording of a car’s mileage for the first three years in which cars are MOT exempt as a contributing factor.
“Cars may need servicing each year, with the car’s mileage recorded in the service book, but a consumer can easily get a car clocked before it goes to the garage,” explains Louise Wallis, the NFDA’s head of business management.
How are cars clocked?
Although it’s illegal to alter a car’s odometer and then sell it on without telling the buyer that the mileage has been changed, the actual act of turning back the odometer is perfectly legal.
In fact, it’s surprisingly easy to do. CTSI’s Gerald Taylor explains: “All new vehicles have digital systems – usually under the driver’s seat or in the engine bay – and it is simple to connect a laptop up to them and use software to alter the mileage.”
The CTSI has been campaigning for years to have these companies and the act of altering a vehicle’s mileage outlawed. The RAC agrees that the current situation isn’t acceptable. Simon Williams says: “It’s absolutely ludicrous that shady operators are able to advertise their services, putting motorists at risk of buying a car with a tampered mileage, disguising its true history and likely level of wear and tear.”
Could a clocked car be dangerous?
One of the biggest risks of buying a clocked car is the increased potential of being involved in an accident. Unsuspecting buyers who think they are purchasing a low-mileage car might not think to check major wear and tear items that would typically last far longer.
For example, if you buy a car thinking it has covered just 5000 miles, you won’t expect the tyres or brake components to be nearing the end of their lives. However, if that car has actually covered 20,000 miles, these items could be worn out – resulting in issues including increased stopping distances.
There’s also a concern about major components failing because they’ve not been replaced at the right time. One of the most important examples is the car’s timing belt. If this isn’t replaced at the correct mileage, it could break, resulting in hugely expensive engine failure.
How to spot a clocked car
1. Get a history check
While a history check can’t guarantee to identify whether a car has been clocked – for instance, if it’s been done by the owner of a car that’s under three years old – it can provide you with a good amount of information to help you decide whether a car you’re interested in is worth your time. A history check can also alert you to other issues, such as if the car has outstanding finance on it or if it has previously been stolen or written off.
One of the best services is the DVLA’s Check MOT History page. By entering the used car’s registration number, you can check previous MOT results, including any advisories and mileages.
Nevertheless, be weary of free or very cheap online car history checks. While these can supply you with basic information about the car, they’re unlikely to be as comprehensive as those offered by the bigger players in this market, which often have access to a wide range of sources to reveal more information about the history of the car in question.
2. Check its service history
A seller who has cared for their car will likely have plenty of previous MOT test documents and a service book full of stamps at the right mileage intervals to show you. Check the car’s service history to make sure there aren’t any gaps, and that the recorded mileages increase at a steady rate each year.
You can also check the results of previous MOTs online at gov.uk/check-mot-history-vehicle. If you’re unsure about the stamps in a car’s service book, you can always call the garages that carried out maintenance to verify exactly what they did.
You can expect newer used cars not to have much in the way of service history – with cars under three years old not requiring an MOT and many models featuring two-year service intervals. However, if an older car is missing its service history, proceed with caution. Talk to the seller and consider getting a pre-purchase inspection.
3. Inspect its condition
While modern cars are generally built to last, you should still be able to spot a car that has covered a high mileage. One of the easiest ways to check for a clocked car is by inspecting the bodywork. In particular, closely inspect the bonnet for stone chips – an indicator of a high motorway mileage – and make sure there are no different shades of colour or inconsistent panel gaps between any body panels or doors, which could indicate repaired crash damage.
Inside, make sure that the driver’s seat is not saggy or visibly worn. Plastic or leather parts typically touched by the driver – such as the steering wheel, gearstick and handbrake – that are shiny can also suggest the car has covered a high mileage.
Just be mindful that cars can be resprayed and worn parts replaced to hide extra wear and tear.
4. Take it for a test drive
When looking for any used car, try to get behind the wheel of two or three examples of that model so you can get a good idea of how it should feel to drive. A high mileage car is likely to have a sloppy gearbox, worn brakes and clutch, and tired suspension.
During your drive, pay attention to any unusual noises or vibrations from the engine, suspension and steering components, which can all give away the truth about how many miles a car has covered.
5. Ask questions
If there are discrepancies between a car’s mileage and its service history or condition, it's important that you ask the seller why. If you’re buying a used car from a dealer, make sure there isn’t a disclaimer in the car’s advert or paperwork that states the mileage hasn’t been verified.
6. Keep checking the odometer
In some cases, unscrupulous car sellers will turn back a car’s mileage so that it looks impressive upon first glance. However, if you decide to buy it, the seller will increase the mileage to its original value so that they can’t be prosecuted for selling you a clocked car.
As a result, make sure to check the mileage when you view the car – and again when you collect the car and flag any discrepancies immediately with the seller.
What Car? says…
With the number of clocked cars on the used car market rising, some in the motor industry believe that the Government should make it illegal for anyone other than franchised dealers to be allowed to alter a car’s odometer – and even then it should be done in certain restricted circumstances, such as when the odometer has broken and needs to be replaced.
What Car? agrees that the Government should do something to stop the scourge of car clocking. Currently, used car buyers risk being thousands of pounds out of pocket and more likely to encounter a breakdown if they unknowingly buy a clocked car.
Worse still, they could be put at risk of being involved in a car accident if they’re driving a car that has covered more miles than they realise.
