London, 15 October 2025 – A new analysis from leading automotive diagnostics platform Carly has exposed a troubling reality for UK used car buyers: vehicle tampering is far more widespread than many realise. According to Carly, more than one in seven cars checked for this year’s data set—spanning over 2.5 million diagnostic sessions from more than 550,000 UK users—showed evidence of mileage rollback or Vehicle Identification Number (VIN) manipulation.
The findings suggest that nearly 16.25 per cent of the used cars on UK roads could be concealing serious hidden issues, leaving unsuspecting buyers vulnerable to overpaying or facing costly mechanical problems.
Mileage Fraud: A Hidden Cost
Dali Ati, Head of Internationalisation at Carly, highlighted the risks: “Mileage tampering can make a car appear newer and more valuable than it really is. But beneath the surface, it could be far more worn—and that’s where unexpected problems begin. We want drivers to feel informed and in control before they spend their money. A quick Carly scan, using the Carly Used Car Check, can uncover these hidden issues in just minutes… and the best part? The scanner costs as little as £41, and these checks can save buyers thousands.”
Odometer tampering is not confined to specific regions. While larger markets and ports naturally see higher transaction volumes, Carly’s data indicates that buyers across the country—from the North of England to the South—are equally likely to encounter vehicles with rolled-back mileage or identity discrepancies.
The Role of Digital Diagnostics
Carly’s technology leverages advanced digital diagnostics, connecting directly to a vehicle’s internal systems through the OBD (on-board diagnostics) port. By cross-referencing mileage readings across multiple control units, the system can detect resets, inconsistencies, and VIN mismatches that would be nearly impossible to spot during a visual inspection.
In an era of economic uncertainty and persistently high new car prices, demand for second-hand vehicles remains strong. Carly urges buyers to conduct digital checks before committing to any purchase, particularly when buying from private sellers or smaller dealerships, where oversight may be limited.
Packages to Protect Buyers
Carly offers two packages—Basic and Premium. The Premium option includes the scanner and unlocks the full suite of functionality, including the Used Car Check, allowing buyers to detect mileage rollback and VIN inconsistencies. With prices starting at just £41, Carly’s tools provide a cost-effective method to safeguard against hidden issues, offering peace of mind in the increasingly complex used car market.
As the used car market continues to grow, tools like Carly are becoming essential for buyers looking to make informed decisions. With hidden tampering affecting nearly one in seven vehicles, a simple digital scan can make the difference between a safe investment and an expensive mistake.
