Hard-to-detect tech is used illegally on UK roads – prompting fears about its use with incoming eVED
The government’s pay-per-mile scheme for electric cars and plug-in hybrid vehicles, which is due to start in two years’ time, faces a major threat from devices called mileage blockers that are easy to buy and to fit and freeze a car’s odometer, an investigation by Autocar has found.
Pay-per-mile charging, officially called eVED, is scheduled to start in April 2028 as an extra tax placed on EVs and PHEVS to recover income lost from fuel duty, given these cars can run fully or partially on electricity. The tax will start at a rate of 3p per mile driven in an EV and 1.5p per mile driven in a PHEV and drivers will need to self-declare their mileage annually.
Concerns are growing that when the scheme is introduced, drivers will fit mileage blockers as a means of avoiding or reducing this levy.
The devices, which range in price from around £200 to £900, are not illegal to sell and are marketed for use on cars being tested or developed away from the road. It is, however, illegal to use a car on the road fitted with one.
Autocar’s investigation has found that hundreds of drivers and businesses are buying and fitting these devices each week, with the aim of reducing or avoiding paying a mileage penalty at the conclusion of a PCP or a lease.
Mileage blockers are available for many popular petrol and diesel vehicles and, increasingly, for electric and hybrid ones. Suppliers claim that when installed in a car’s on-board computer, the device prevents a vehicle from adding mileage data to any ECU or module as well as, where enabled, to the ignition key. They claim a blocker is easy to install but difficult to detect.
Given that difficulty to detect, there are additional fears that increasing numbers of EVs and PHEVS previously fitted with the devices will enter the used car market (potentially without the current owner knowing), boosting the number of clocked cars already in circulation.
Posing as a customer, an Autocar reporter contacted a leading supplier of mileage blockers. The reporter said he owned a Volkswagen ID 3 registered in 2022 and was interested in buying a mileage blocker for the vehicle. A salesperson said the firm could supply a device that was safe and reliable. The salesperson added that each month his business sold 500 blockers to retail customers and 250-300 to the trade, and that new devices were becoming available each month.
“Our supplier in Germany has just cracked the post-2024-model VW Passat and hopes to have cracked the rest of the 2024 VW range within the next few months,” he said. “Also, they are just about to finish developing blockers for Omoda, Jaecoo and Chery vehicles.”
The law makes no mention of mileage blockers but simply states that selling a vehicle whose mileage has been altered and not disclosing that fact is illegal.
The company that Autocar contacted states that a mileage blocker is a “legitimate tool for research and development purposes“ and warns that driving a car on the road fitted with one is illegal. However, it also explains that mileage blockers are popular because “they have the potential to save drivers from big fines and higher insurance quotes“ and “are becoming increasingly popular in the UK as more people look for ways to save money on their motoring costs”.
Commenting on the availability of mileage blockers for the VW ID 3 and other Volkswagen Group vehicles, a spokesperson for VW said: “Mileage blockers are available to buy online for most vehicle makes but are designed for specific circumstances only. It is illegal to use them on public roads and anyone installing one risks safety and a criminal conviction if they subsequently sell the car without telling the buyer the mileage has been altered. If our technicians discovered a blocker when inspecting a vehicle, they would alert the customer to its presence.”
Autocar shared the results of its investigation with Cap HPI, a vehicle data checking service.
Wendy Swaine, the company’s expert in vehicle provenance, said: “The only reason people tamper with a car’s mileage is for financial gain – for example, to avoid paying the mileage penalty on a PCP or lease contract and, from April 2028, perhaps also to reduce their eVED liability.”
Peter Golding, CEO of FleetCheck, a fleet software management company, said the introduction of eVED will greatly increase the temptation to clock a car. “If you’re covering 20,000 miles a year in an EV, your eVED bill will be £600. For a few people, the ease with which that amount can be reduced will be difficult to resist. This is an issue that has very real potential to increase the number of clocked vehicles on the used market.”
Presented with Autocar’s findings, a spokesperson for the Treasury, which is responsible for the implementation of eVED, said it is “considering further options to mitigate against odometer tampering and intends to engage with manufacturers, the leasing industry and insurers to minimise fraud”. The spokesperson added that “any necessary legislative, regulatory and technical steps will be taken to widen existing law and strengthen enforcement”.




