Used Diesel Prices Rise Amid Reduced New Car Supply

The demand for diesel vehicles may be decreasing in the new car market, but surprisingly, the value of certain used diesel models is actually climbing, according to leading vehicle valuation experts.

Declining New Diesel Registrations

In the first half of 2025, registrations for new diesel cars totaled only 58,722 units, marking an 11.3% decline from 2024. This trend continues a downward trajectory that began in 2017, influenced by the aftermath of the Dieselgate scandal and increasing concerns over future vehicle taxation and emissions penalties.

As fewer car manufacturers continue to produce diesel models—such as Audi, BMW, and JLR (especially with the Defender)—alternative powertrains like petrol, hybrid, and electric vehicles are gaining traction.

Surging Values for Certain Models

While most diesel cars are experiencing depreciation, some are defying this trend with significant increases in their values. For instance, recent reports from Cap HPI indicate that a three-year-old diesel Honda HR-V with 60,000 miles is currently valued at 11.3% more than it was a year ago. Additionally, the value of a Mercedes CLS has gone up by 8%, and a Ford Mondeo has increased by 6.5%.

Dylan Setterfield, Head of Forecast Strategy at Cap HPI, explains, “There is ongoing demand for diesel in the used market from both consumers and dealers, with fuel economy remaining a key consideration for high-mileage drivers.”

Setterfield adds, “New diesel car volumes have been declining for some time, which is leading to decreased used car supplies. We anticipate that these reductions will partially offset ongoing changes in consumer demand, with diesel prices aligning more closely with petrol vehicle prices in the years ahead.”

Market Extremes and Depreciating Models

Despite pockets of resilience, the market also showcases extreme variations in valuation. Some models are depreciating faster than expected; for example, a three-year-old Ssangyong Korando 2.2D with 60,000 miles has seen a staggering drop in value of 24.5%. Similarly, a Vauxhall Astra has depreciated by 20.2%, and a Range Rover Evoque has fallen by 12.7%.

Setterfield notes, “The Korando’s drop seems to be linked to market uncertainty as the brand transitions to KGM. Higher-mileage Astra diesels are facing increased penalties, while the Evoque’s decline is tied to a rise in used inventory following previous supply shortages.”

For the majority of diesel vehicles, however, the market has demonstrated relative stability, with average values for three-year-old diesels declining by only 2.1% compared to 1.3% for petrol cars. At 12 months and 20,000 miles, the values shift slightly, showing a 1.4% drop for diesels against a 1.6% drop for petrol.

Philip Nothard, Insight Director at Cox Automotive International, commented on the return of stability to most segments of the diesel market. “After the dramatic price highs during the post-Covid era, when even two- to four-year-old diesels were worth 73% of their initial prices, we are now seeing a reversion to a more predictable market.”

Future Outlook

Motorpoint, a major car supermarket, typically stocks around 5,000 vehicles, primarily those four years or younger. Currently, only about 350 of these are diesels or diesel hybrids, indicating a tight supply. Mark Carpenter, CEO of Motorpoint, believes that while the demand for diesels has decreased noticeably, the limited availability of new diesel vehicles means that used options will become increasingly scarce.

However, Carpenter cautions that any potential surge in used diesel demand may not lead to dramatic price increases. “While a rise in demand for used diesel vehicles could influence prices to some extent, the aging diesel stock on the market may reduce its attractiveness for buyers seeking nearly new cars.”

In summary, while the diesel powertrain may be on its way out, certain models are still holding their value, reflecting a complex and evolving market landscape.