9:24 am, October 12, 2026
Used diesel car values have plunged by almost 7% over the past year as soaring fuel prices put buyers off the once-popular fuel type.
New figures from Cap HPI show that diesel values at three years and 30,000 miles have fallen 6.9% over the past 12 months, with the decline gathering pace since March.
The slump comes as diesel prices have climbed to around 195p per litre, some 23p more than petrol, making a typical fill-up cost approximately £105.
With some forecourts now charging more than £2 per litre, buyers are increasingly turning to hybrid and electric alternatives, leaving dealers facing slower stock turn for diesel models.
According to Cap HPI, used diesels took an average of 41 days to sell in September, compared with just 32 days for hybrids and 33 days for battery-electric vehicles.
The latest monthly figures also show diesel has been the worst-performing fuel type for five consecutive months.
At three years and 60,000 miles, diesel values dropped a further 0.6% in October, while hybrids rose 0.5% and EVs increased 0.3%.
Chris Plumb, head of current valuations at Solera cap hpi, said: ‘The change in diesel values has become much more pronounced since March.
‘Over the past 12 months, values at three years and 30,000 miles have fallen by 6.9%, and the trajectory shows how quickly buyer sentiment towards running costs can feed through into used car prices.
‘Diesel at around 195p a litre is difficult for buyers to ignore, particularly when they are comparing it with hybrid and electric alternatives.
‘Retailers are seeing that reflected in demand, with diesel stock needing to be particularly desirable or competitively priced.’
He added that hybrids were proving particularly resilient, with buyers attracted by lower fuel costs without having to change their refuelling habits.
Despite the difficulties facing diesel, the wider used car market remains relatively stable.
Across all fuel types, average values at three years and 60,000 miles slipped by just 0.3% in October, equivalent to a little over £90.
Plumb added: ‘Hybrid is proving much more resilient. For many buyers it offers lower fuel costs without requiring a change in how they use or refuel their car, and that is supporting demand and values.’