In brief
The National Highway Traffic Safety Administration's revised standard sets the 2031 fleetwide average at 34.5 mpg, down from the 50.4 mpg target finalized in 2024.
The rollback follows the One Big Beautiful Bill Act passed in 2025, which removed consumer EV tax credits and noncompliance penalties for carmakers.
US retail gasoline prices averaged just under $4.50 per gallon on 26 September 2026, following price increases tied to the war involving the US, Israel, and Iran.
Transportation officials estimate the lower standards will reduce vehicle purchase prices while increasing long-term fuel consumption and carbon dioxide emissions.
- December 2025Trump administration proposes 34.5 mpg fleet average standard for 2031
- February 2026Environmental Protection Agency moves to scuttle motor vehicle climate rules
- 26 SeptDonald Trump announces approval of revised fuel economy standards
New efficiency targets for 2031
US President Donald Trump announced on 26 September 2026 that he approved revised Corporate Average Fuel Economy (CAFE) standards for passenger cars and light-duty trucks. The revised regulation, developed by the National Highway Traffic Safety Administration, sets the required industry fleetwide average efficiency at roughly 34.5 miles per gallon (14.7 kilometres per litre) through model year 2031. This rule replaces fuel economy standards finalized by the Biden administration in 2024, which scheduled fleetwide efficiency to rise from 39.1 mpg to approximately 50.4 mpg (21.4 km/l) by 2031. The adjustment lowers the scheduled 2031 efficiency benchmark by nearly one-third.
- Biden administration standard (2024)
- 50.4 mpg
- Trump administration standard (2026)
- 34.5 mpg
Data from the article text
The US Department of Transportation plans to finalize the regulation on Monday. Trump announced the decision on Truth Social, asserting that previous requirements imposed excessive costs on domestic automobile manufacturing and aimed to force consumer adoption of electric vehicles.
“These new Standards will take the waste out of building cars in America. That means LOWER PRICES, saving families thousands on a new, beautiful, and safe car.”
Regulatory framework and legislative revisions
The CAFE system was established by the US Congress in 1975. The mechanism requires automotive manufacturers to meet fleetwide average fuel economy targets across all cars and light trucks they sell, obliging companies that sell fuel-inefficient models to balance them with higher-efficiency offerings. Although Trump and Republican officials termed the 2024 rules an electric vehicle mandate, federal statutes contained no direct requirement for consumers to buy electric cars or prohibitions on petrol-powered vehicles.
The change follows earlier administrative proposals and legislative measures enacted over the preceding year. Trump first proposed the 34.5 mpg standard for light-duty vehicles in December 2025. In 2025, the Republican-controlled Congress passed the One Big Beautiful Bill Act, which removed consumer tax incentives for electric vehicles and set aside the financial penalties carmakers previously paid for missing CAFE averages. In February 2026, the Environmental Protection Agency moved to dismantle motor vehicle climate rules, including the scientific findings behind them. Joshua Linn, a professor at the University of Maryland, observed that the repeal of noncompliance penalties transformed CAFE standards into a suggestion.
Economic context and automaker response
Estimates from the Department of Transportation indicate that while the revised standards will lower new vehicle purchase prices, they will result in higher fuel consumption and increased carbon dioxide emissions over several decades. Automakers including General Motors, Ford, and Stellantis had previously ramped up electric vehicle manufacturing to meet the Biden administration's 50.4 mpg requirements.
The regulatory rollback occurs as US motorists navigate elevated fuel prices, with nationwide gasoline costs averaging just under $4.50 per gallon on Saturday. Fuel prices increased following the outbreak of war between the United States, Israel, and Iran in late February 2026. Transportation Secretary Sean Duffy defended the revisions on social media ahead of the formal administrative rollout.
“A major victory for America's auto workers is COMING MONDAY.”