CALSTART’s 2025 ZEB report shows U.S. transit agencies continue to adopt zero-emission vehicles

The transition to zero-emission transit buses (ZEBs) in the U.S. continues to gain momentum despite industry headwinds, such as lingering supply chain issues and a smaller manufacturing pool for transit vehicles, according to a report from CALSTART. 

CALSTART’s 2025 Zeroing in on ZEBs, an annual report funded by the Federal Transit Administration (FTA) and the California Air Resources Board’s Hybrid and Zero-Emission Truck and Bus Voucher Incentive Project (HVIP), provides an updated index of adopted ZEBs that have been funded, ordered and/or delivered within the U.S. and Canada according to data collected through September 2024. Tracking the data shows the countries’ progress towards 100 percent zero-emissions vehicle adoption. The report notes that if the current pace continues, the U.S. is on track to surpass 15,000 full-size ZEBs by 2030. 

Data from the report shows: 

• Full-size ZEB adoptions have grown to 7,028 as of July 2024, an increase of 14 percent from the previous 2023 count. 
• Battery-electric buses remain the dominant bus type, with 6,453 either awarded, ordered, delivered or in operation while fuel cell electric buses saw a 55 percent growth from 2023, reaching a total of 575 throughout the U.S. 
• The adoption of small ZEBs is also expanding, with deployments in public transit fleets increasing by 25 percent, private fleets by 13 percent and university fleets by 121 percent. 

“The continued growth of zero-emission transit buses in the United States reflects the commitment of transit agencies to cleaner, more sustainable transportation. Despite industry challenges, we’ve seen a 14 percent increase in full-size zero-emission bus deployments over the past year, demonstrating resilience and progress toward a zero-emission future. It is only with strong federal and state support that we can build on this momentum and continue,” said Mike Hynes, deputy director, transit, CALSTART. 

Federal investments and state leadership 

In 2024, the FTA awarded nearly $1.5 billion in funding through the Low and No Emission Program and the grants for Bus and Bus Facilities Program, which supported: 

• Nearly 600 new ZEBs (48 percent of buses awarded under the program). 
• Crucial charging and fueling infrastructure projects across 47 states and territories. 

CALSTART notes while federal funding remains a critical piece of the puzzle, state-led initiatives are proving essential in sustaining ZEB adoption. The leaders in full-size ZEBs include: 

• California (2,285) 
• New York (779) 
• Florida (516) 
• Washington (356) 
• Massachusetts (292) 

CALSTART says programs like California’s HVIP and New York’s Truck Voucher Incentive Program are helping offset vehicle costs and accelerate adoption. CALSTART notes many transit agencies are also adopting joint procurement models to streamline purchasing and reduce costs, further strengthening the market.