Wholesale used-vehicle prices fell in September for the first time since early 2025, reversing gains from the first half of the year. The Manheim Used Vehicle Value Index, which tracks auction prices paid by dealerships, dropped to 205.9 in September, a 0.6% decline from September 2025 and a 1.1% decrease from August after adjusting for vehicle mix, mileage, and seasonality. On an unadjusted basis, prices fell 1.2% year-over-year and 1.3% month-over-month.
A separate measure, the Black Book Used Vehicle Retention Index, showed an even steeper decline. The seasonally adjusted index fell 3.1% to 139.7 in September, down 3.3% from September 2025 and 3.1% from August. Unlike Manheim’s index, Black Book’s measure tracks the wholesale value of two- to six-year-old used vehicles as a percentage of their original manufacturer’s suggested retail price, weighted by registration volume and adjusted for age, mileage, and seasonality.
Market Forecasts Adjust Downward
Cox Automotive, which publishes the Manheim index, revised its 2026 forecast for the index from a 2% increase to a 0.2% uptick, citing accelerating depreciation in the third quarter. The company had previously expected modest gains despite economic pressures. Jeremy Robb, Cox Automotive’s chief economist, attributed the reversal to rising fuel costs, record diesel prices, and climbing interest rates, which have dampened demand. He noted that while the first half of 2026 showed unusual appreciation, the third quarter’s decline reflects broader economic strain.
Black Book similarly expects continued depreciation in the fourth quarter, citing seasonal pressures and manufacturer incentives as key factors. The firm’s vice president of data and analytics, Laura Wehunt, stated in a release that the September decline was more pronounced than earlier in the summer, signaling a potential trend.
Sector-Specific Trends
The decline was not uniform across vehicle types. Electric vehicles (EVs) and smaller, fuel-efficient models saw increased demand, while large trucks and SUVs underperformed. Cox Automotive highlighted growing EV sales and off-lease volumes as reshaping the used-vehicle market, with retail prices traditionally following wholesale trends. The company’s revised forecast suggests the market may stabilize by year-end, but risks remain tied to economic conditions.
Historical Context
The Manheim index’s historical average shows a 2.3% year-over-year gain, but last year’s increase was just 0.4%, following a historic surge during the coronavirus pandemic. The September decline marks a notable shift from the first half of 2026, when wholesale values appreciated despite economic headwinds. Analysts now caution that the fourth quarter may bring further volatility as seasonal factors and consumer spending pressures intensify.