Clean fleet mandates are no longer a California story. Eleven states have adopted the Advanced Clean Trucks rule, and fleet operators in New York, Massachusetts, Washington, and seven other states are operating in a regulatory environment that is actively changing the commercial vehicle market around them.
Here is what makes this moment complex: the landscape shifted sharply in 2025. Congressional Review Act resolutions signed in June 2025 repealed California’s federal Clean Air Act waivers for the Advanced Clean Trucks rule and related regulations, creating legal uncertainty across every state that adopted California standards. Some states are pausing enforcement, while others are pressing forward. Fleet operators building a multi-year procurement plan need an accurate picture, not an oversimplified one.
That uncertainty is not a reason to wait. Here’s why.
Key Takeaways
- Eleven states have adopted the Advanced Clean Trucks (ACT) rule, but enforcement is in flux after June 2025 federal waiver repeals.
- ACT regulates manufacturers, not fleets. It requires truck makers to sell increasing percentages of zero-emission vehicles, which shifts available inventory regardless of fleet-level mandates.
- Only California’s Advanced Clean Fleets (ACF) rule directly requires fleet operators to purchase ZEVs. No other state has adopted ACF.
- Infrastructure lead times of six to 18 months create independent timing pressure that does not pause for regulatory uncertainty.
- Waiting is the expensive option. Reactive procurement typically means higher acquisition prices, reduced incentive availability, and compressed infrastructure timelines.
Quick Answer
Eleven states have adopted the Advanced Clean Trucks (ACT) rule. Congressional Review Act actions in June 2025 repealed California’s federal waivers, creating enforcement uncertainty in Section 177 states. Fleet operators should verify current status with their state agency. Regardless of mandate enforcement, state incentive programs and infrastructure lead times of six to 18 months create independent, time-sensitive reasons to begin fleet electrification planning.
What Is the Advanced Clean Trucks Rule and Who Does It Affect?
The Advanced Clean Trucks (ACT) regulation was adopted by California’s Air Resources Board (CARB) in 2020. It requires truck manufacturers, not fleet operators directly, to sell an increasing percentage of zero-emission vehicles annually, by vehicle class.
Under the federal Clean Air Act, states other than California can adopt California’s vehicle emissions standards in place of federal standards. These Section 177 states have progressively adopted the ACT rule, which means the composition of available commercial truck inventory is shifting in those markets as manufacturers work toward compliance.
By model year 2035, the regulation targets 55 percent of Class 2b-3 truck sales as zero-emission, 75 percent of Class 4-8 straight trucks, and 40 percent of Class 7-8 tractors in states that have adopted the rule.
The Advanced Clean Trucks rule does not require fleet operators to buy electric vehicles. It requires manufacturers to sell increasing percentages of them. As those percentages rise, the composition of available inventory changes, and fleets without EV procurement capability will compete for limited ZEV models at accelerating demand. Understanding which vehicles to electrify first becomes a procurement-readiness question, not a compliance one.
Which States Have Adopted Clean Fleet Mandates, and What Is the Current Enforcement Status?
As of 2026, eleven states have adopted the ACT rule. Enforcement status is in flux following the June 2025 federal waiver repeal. Operators should verify current status directly with the relevant state agency before making compliance commitments.
California has the ACT rule in effect plus the Advanced Clean Fleets (ACF) regulation, which directly requires certain large fleets to begin zero-emission transitions on defined timelines. ACF is California-specific. No other state has adopted it.
New York adopted the ACT rule in December 2021, effective for the 2025 model year. The state also operates the NYTVIP voucher program independently of federal waiver status.
Massachusetts adopted the ACT rule effective for the 2025 model year. Multiple bills in 2025 sought to delay implementation. MOR-EV Trucks remains an active state incentive program.
Washington adopted the ACT rule effective for the 2025 model year. Legislation to repeal adoption has been introduced; verify current status with the Washington Department of Ecology.
Colorado, Maryland, New Mexico, and Rhode Island adopted the ACT rule with implementation beginning with the 2027 model year. Oregon, New Jersey, and Vermont have adopted the rule with varied effective dates.
The Alternative Fuels Data Center’s state laws and incentives database provides regularly updated information on current state EV program status.
Federal Waiver Update: Congressional Review Act resolutions signed in June 2025 repealed California’s Clean Air Act waivers for the Advanced Clean Trucks and related rules. This creates legal uncertainty for Section 177 states. Fleet operators should monitor developments and consult compliance counsel regarding current enforcement status in their specific operating states.
What Is the Real Cost of Waiting for Regulatory Clarity?
That assumption is where the plan quietly slips. Fleet operators who treat regulatory uncertainty as a reason to pause electrification planning are making two related mistakes.
The first is timing. Depot charging infrastructure, from initial planning through utility interconnection to operational readiness, typically takes six to 18 months. That timeline runs independent of any mandate. Operators who wait for regulatory certainty before beginning infrastructure planning will face a compressed timeline when they do move.
The second is incentive availability. State programs have their own funding cycles that do not pause during regulatory disputes. The operators who capture funding in open application windows are the ones who are ready when windows open, not the ones who are still deciding whether to start. Inspiration’s Electrification Finance team integrates incentive capture into every deal structure.
The cost of a proactive, phased approach is the capital and time invested in planning. The cost of a reactive, mandate-deadline-driven approach is typically higher vehicle acquisition prices, reduced incentive availability, and compressed infrastructure timelines that create operational risk.
How Do You Build a Fleet Electrification Roadmap Around Mandate Timelines?
A mandate-aware fleet electrification roadmap has three elements that remain valid regardless of how the ACT legal situation resolves.
First, a compliance exposure map: which vehicles in your fleet operate in ACT states, what are their vehicle class designations, and what does current regulatory activity mean for procurement decisions in those markets.
Second, an infrastructure lead time plan. Charging infrastructure needs to be in development ahead of mandate timelines, not concurrent with them. Utility interconnection timelines are outside your control once the process starts.
Third, an incentive capture plan. Program availability, eligibility criteria, and application windows change. The operators capturing available state funding have identified eligibility and have acquisition agreements ready to move when windows open.
Frequently Asked Questions
What states have adopted the Advanced Clean Trucks rule?
Eleven states have adopted the ACT rule: California, New York, Massachusetts, Washington, Oregon, New Jersey, Vermont, Colorado, Maryland, New Mexico, and Rhode Island. Implementation dates vary by state and model year. Following Congressional Review Act actions in June 2025 that repealed California’s federal waivers, enforcement status is in flux. Fleet operators should verify current status with the relevant state agency.
Does the Advanced Clean Trucks rule require fleet operators to buy EVs?
No. The ACT rule places the compliance obligation on manufacturers to sell increasing percentages of zero-emission vehicles annually, not on fleet operators to buy them. However, California’s separate Advanced Clean Fleets regulation does directly require certain large fleets in California to purchase zero-emission vehicles on defined timelines. No other state has adopted the ACF regulation.
How do clean fleet mandates affect commercial vehicle availability?
As manufacturers increase their zero-emission vehicle sales percentages to meet ACT requirements in mandate states, the available inventory mix shifts toward ZEV models. Fleets that have not built EV procurement capability, established manufacturer relationships, or placed vehicle reservations may find themselves competing for limited inventory as mandate-driven demand accelerates.
What should fleet operators do if their state has uncertain mandate enforcement?
Verify current enforcement status with the relevant state agency and consult compliance counsel. Do not pause infrastructure planning or incentive program engagement based on enforcement uncertainty alone. Infrastructure lead times of six to 18 months, state incentive funding cycles, and vehicle manufacturer reservation timelines create independent planning pressures that apply regardless of how the mandate legal situation resolves.
Inspiration Mobility’s eFMC model helps fleet operators map compliance exposure, infrastructure lead times, and incentive eligibility into a single mandate-aware roadmap.
Schedule a Fleet Electrification Review and understand your mandate exposure, incentive eligibility, and infrastructure timeline in your specific operating markets.