After a slower first half of 2025, zero-emission truck (ZET) deployment in the United States gained momentum in the second half of the year, with ZETs representing 4.14 percent of all truck deployments from July through December 2025, up from 1.32 percent in the first half of the year, according to the June 2026 edition of CALSTART’s biannual Zeroing in on ZETs report.
New state leaders advancing in the race to zero signal that the transition to cleaner technologies is not a geographically concentrated trend focused on a single vehicle segment, but rather a broader movement that reflects state policy in action.
Normalized ZET score leaders changed from the last report, with California (3.11), New York (0.97), and Pennsylvania (0.97) now leading the nation in advancing adoptions. New York and Pennsylvania are comparable states, both in the Northeast, ranking in the top 10 for truck stock, and with similar economic aspects. Years of strong policy decisions, state funding programs like the New York Truck Voucher Incentive Program (funded by the New York State Energy Research and Development Authority) and the Pennsylvania Freight Innovations in Transportation Grant Program (administered by the Pennsylvania Department of Environment as part of the Driving PA Forward Initiative), workforce development, and infrastructure planning have helped both states emerge as leaders. Their performance on CALSTART’s normalized ZET score suggests that combined policy, economics, and awareness around ZETs can help identify where national adoption is advancing most rapidly and where additional support may be needed.
Other key findings in the report include:
“The market, even absent tax credits, has shown positive growth. The data points to a strong zero-emission future as operational cost advantages continue to accelerate over fossil fuels, capital costs continue declining, and operator acceptance trends in a positive direction. This report continues to play a vital role in mapping the trajectory and consequences of ZET adoption across the country,” said Jared Schnader, Executive Vice President of Initiatives in CALSTART’s Florida Regional Office.
Overall, 2025 data shows that the U.S. ZET market continues to grow and suggests that state leadership remains essential to furthering vehicle adoption. Policy and vehicle market readiness will continue to play major roles in carrying momentum.
As stated in the last market update, the next wave of adoption will depend on how states, infrastructure providers, fleets, and stakeholders collaborate to address common challenges such as upfront vehicle and infrastructure costs and the development of public and private charging networks (to see where public charging facilities are currently available for ZETs, view CALSTART’s National Medium- and Heavy-Duty Zero-Emission Infrastructure Map, led by the Zeroing in on ZETs report co- author Jacob Richard).