The Trump administration has formally revised America's corporate average fuel economy standards, cutting the 2031 target from 50.4 miles per gallon to 34.5 mpg — a reduction of nearly 33 per cent. The change, described by officials as a «reset», marks one of the most significant reversals of federal vehicle efficiency policy in decades.
Announcing the revised rules, the administration acknowledged that the lower standards will result in billions of additional gallons of petrol being burned. It framed the decision as a response to consumer demand, arguing that the previous targets would have pushed up vehicle prices and limited the availability of the affordable cars Americans are said to want.
The scale of the rollback is substantial. The original 2031 goal of 50.4 mpg represented a near-doubling of real-world fleet efficiency compared with earlier decades, and was designed to accelerate the shift towards hybrid and electric vehicles. By lowering the target to 34.5 mpg, the administration is effectively slowing that transition, giving manufacturers more room to sell conventional petrol-powered models without incurring penalties.
Critics of the move point to the public health and environmental costs, which they describe as potentially colossal. Higher fuel consumption translates directly into greater tailpipe emissions, including carbon dioxide and pollutants linked to respiratory illness. The administration itself has not disputed that more petrol will be burned; it has instead argued that the trade-off is justified by lower upfront costs for buyers.
The revision forms part of a broader pattern of federal support being withdrawn from clean energy and electric vehicles. In 2025, the United States lost 36,949 clean energy jobs, ending four straight years of growth. Analysts attributed that decline directly to the administration and a Republican-controlled Congress rolling back federal backing for clean energy and EVs, which led companies to cancel or scale back projects.
For the car industry, the new standards create a period of uncertainty. Manufacturers had invested heavily on the assumption that efficiency requirements would tighten steadily through the next decade. Some may now adjust product plans, delaying electric models or extending the life of existing petrol platforms. Others may continue their electrification strategies regardless, particularly where global markets and state-level rules demand it.
California and several other states have historically set their own stricter emissions standards, and legal battles over the federal government's authority to weaken national rules are widely expected. The administration's position is that uniform, less stringent standards prevent a patchwork of state regulations that it says drives up costs for consumers.
Environmental and consumer groups have signalled that they will challenge the revision, arguing that it transfers costs from the showroom to the petrol pump and to public health systems. Supporters counter that it protects household budgets and preserves consumer choice at a time when electric vehicle prices remain high and charging infrastructure is uneven.
The practical effect will unfold over several years. Fuel economy standards work through gradual annual increases, so the full impact of the lower 2031 target will not be felt immediately. What is clear is the direction of travel: the United States has stepped back from the most ambitious vehicle efficiency trajectory it had ever set, and the administration has said plainly that more petrol will be consumed as a result.