The Trump administration has rolled back US fuel economy standards for cars and light trucks, reversing five decades of steadily tighter rules. The new 2031 target is 34.9 miles per gallon, far below the 50.4 mpg planned under Joe Biden. The change also eases pressure on carmakers to sell electric vehicles.
What has the US government changed?
The US Department of Transportation and the National Highway Traffic Safety Administration (NHTSA) have relaxed the Corporate Average Fuel Economy rules, known as CAFE. The revised policy requires cars and other light vehicles to reach 34.9 miles per gallon by 2031. By contrast, former president Joe Biden’s plan called for new cars to hit 50.4 mpg over the same period.
The changes cover passenger cars and light trucks with model years from 2022 to 2031. Under the new rules, fuel efficiency will rise by up to 1 per cent each year. That’s a much slower climb than the Biden-era target implied. As a result, carmakers face a far lower bar over the rest of the decade.
Why does this break with 50 years of policy?
US fuel economy regulation dates back to the 1975 Energy Policy and Conservation Act. Since then, the rules have generally tightened, and cars have grown more efficient alongside them. In 1975, the average passenger car covered 13.1 miles on a single gallon of fuel. By 2024, that figure had climbed to 35.4 miles per gallon.
Notably, the new 2031 figure sits slightly below that 2024 average. On paper, then, the benchmark for the coming years is lower than what the typical car already managed. That comparison helps explain why critics call the move a U-turn. For half a century, each administration broadly pushed the numbers in one direction. Now that trend has stopped.
What does the government say?
Transportation Secretary Sean Duffy said in a statement that the rule change would lower car prices. In the same statement, NHTSA chief Jonathan Morrison backed that argument. “Newer cars are safer cars,” he said.
Morrison went further. “By reducing vehicle prices, more American families will be able to afford newer vehicles, and sensible standards allow automakers more freedom to design and produce vehicles consumers actually want,” he said.
The administration’s case therefore rests on affordability and safety. In its view, cheaper new cars would encourage families to replace older vehicles sooner. Meanwhile, looser standards would give manufacturers more room to decide what they build and sell.
Why are environmental groups worried?
Environmental advocates have condemned the decision. Andy Su, a transportation lawyer at the non-profit Environmental Defense Fund, warns of a “disastrous future” for both the economy and the environment.
His argument centres on running costs. Lower fuel efficiency means more trips to fill up over a car’s lifetime. Su estimates this will cost drivers at least $1,600 each. That figure is the Environmental Defense Fund’s own estimate, and it hasn’t been independently verified.
“For decades, our national fuel economy standards have steadily made our vehicles more efficient and less expensive to drive,” Su says. He adds that the new standards “are a sharp U-turn that will mean more wasted gas, more pollution and higher costs for Americans who are already struggling with higher fuel prices.”
So the two sides frame affordability very differently. The government focuses on the sticker price of a new car. Critics, on the other hand, point to what drivers spend on fuel over many years of ownership.
What does it mean for electric cars?
Fuel economy targets have long shaped carmakers’ product plans. CAFE rules judge each manufacturer on the average efficiency of the vehicles it sells. Because EVs use no petrol, they help lift that average.
A strict target, therefore, gives companies a strong reason to push electric models into showrooms. A weaker target reduces that pressure. In practice, carmakers selling in the US will now have more freedom to lean on petrol-powered cars and trucks without falling short of the rules.
Still, the standards set a minimum. Nothing stops a company from beating them. Other factors, such as fuel prices, battery costs and buyer demand, will also influence how quickly Americans switch to electric cars.
What happens next?
For now, the relaxed targets apply up to model year 2031. Supporters expect lower prices and more choice for buyers. Critics, meanwhile, expect higher fuel bills and more pollution over time.
For drivers, the real effect will depend on the cars manufacturers decide to build under the new limits. Some firms may keep investing in efficient and electric models regardless. Others may take the opportunity to slow down. Either way, the decision ends a long run of tightening rules in one of the world’s biggest car markets.
