Zero-emission Vehicle Regulation

Zero-emission Vehicle Regulation
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Primary Contact

Advanced Clean Cars

cleancars@arb.ca.gov

About

Since 1990, the California Air Resources Board’s (CARB) Zero-emission Vehicle (ZEV) Regulation has required automakers to deliver zero-emission vehicles, like electric-, plug-in hybrid-electric, and fuel-cell electric vehicles, to the California market. Most recently, the ZEV Regulation was included in the Advanced Clean Cars Program, which combined several vehicle standards into a single coordinated effort.

A New Phase of Vehicle Standards

In response to illegal federal actions purporting to revoke California’s Clean Air Act waiver for the enforcement of the Advanced Clean Cars II regulations, Governor Gavin Newsom signed Executive Order N-27-25 on June 12, 2025. This order reaffirms the state’s commitment to cut harmful air pollution from transportation and protect public health.

CARB staff has begun a new phase of work that includes light-duty vehicle emissions standards to reduce criteria air pollutant, greenhouse gas, and toxic emissions consistent with State and federal law. To learn about CARB’s new phase of vehicle standards, visit the Drive Forward Vehicle Standards page.

Manufacturer Compliance with the ZEV Regulation

CARB releases annual credit bank balances each year, as well as the total number of vehicles produced for that model year and the total number of zero-emission vehicles and plug-in hybrids.

Other States Have Adopted the ZEV Regulation

Other states can adopt California’s standards through Section 177 of the Clean Air Act, hence why they are often called the Section 177 states. See the latest states that have adopted the ZEV regulation.

ZEV Resources

California’s ZEV market continues to expand as more vehicle models become available and market uptake grows. Veloz's California Market Report provides up-to-date data on sales, infrastructure, and market uptake trends, while ElectricForAll.org helps consumers compare available models, incentives, and fueling or charging options.

A reliable network of charging (link to charging page) and hydrogen fueling stations (link to h2 page) is essential to support this growth. State agencies, electric utilities, and private partners are working to expand the infrastructure, and progress can be tracked through the California Energy Commission Zero-emission Vehicle and Infrastructure Statistics Collection.

Incentives also play a key role in making zero-emission vehicles more affordable. Rebates and income-based assistance can be found at ElectricForAll.org.

California EV Market Report
ElectricForAll.org - Learn how electric vehicles can fit your lifestyle and budget.
Energy Commission Zero-emission Vehicle and Infrastructure Statistics Collection

ZEV Regulation Timeline as of Sept. 26, 2025

2025	The new federal administration has been targeting CARB’s most progressive vehicle emissions standards. In response to illegal federal actions purporting to revoke California’s Clean Air Act waiver for the enforcement of the Advanced Clean Cars II regulations, Governor Gavin Newsom signed Executive Order N-27-25 on June 12, 2025. This order strengthens the state’s commitment to cut harmful air pollution from transportation and protect public health. CARB staff begin a new phase of work that includes light-duty vehicle emissions standards (link to main vehicle emissions standards page) to reduce criteria air pollutant, greenhouse gas, and toxic emissions consistent with State and federal law.
2022	The Advanced Clean Cars II regulations were adopted, imposing the next level of low-emission and zero-emission vehicle standards for model years 2026-2035 and subsequent that contribute to meeting federal ambient air quality ozone standards and California’s carbon neutrality targets. Formal regulatory documents can be found here.
2017	In March 2017, CARB staff presented the Board with the results of CARB's Midterm Review. In addition, staff had been providing yearly status updates to the Board since the Advanced Clean Cars regulations were first adopted in January 2012.
2015	2015 Regulatory Activities \| The 2015 modifications were developed to ensure that any additional ZEV credits awarded to fast refueling ZEVs were awarded on a one-to-one basis. The proposed rulemaking action was withdrawn on December 1, 2015.
2014	2014 Regulatory Activities \| The 2014 amendments provided greater flexibility to intermediate-volume manufacturers in complying with their ZEV credit obligations, while still maintaining the Board’s commitment to a strengthened ZEV regulation. On October 12, 2015, Office of Administrative Law (OAL) approved ZEV regulation amendments adopted by the Board on May 21, 2015. The rulemaking became effective on January 1, 2016.
2013	2013 Regulatory Activities \| Staff proposed minor modifications for the ZEV regulation to include clarifying the Section 177 state optional compliance path provision, defining how caps apply to an auto manufacturer's requirement, and excluding battery swapping as a fast refueling technology. OAL approved the 2013 rulemaking and filed it with the Secretary of State on July 10, 2014. The rulemaking became effective the same day.
2010 - 2012	2010-2012 Regulatory Activities \| The 2012 modifications combined the control of smog-causing pollutants and greenhouse gas emissions into a single coordinated package of standards called Advanced Clean Cars. California's Low-Emission Vehicle (LEV) regulations were amended, known as LEV III, to increase the stringency of tailpipe and greenhouse gas emission standards for new passenger vehicles. OAL approved the 2012 rulemaking and filed it with the Secretary of State on August 7, 2012. The regulation became effective the same day.
2009	2009 ZEV Program Review \| Staff went to the Board in December 2009 per Resolution 08-23. The Board directed staff to review the ZEV regulation, keeping in mind California’s long-term air quality and greenhouse gas emission reduction goals. Staff held a 2009 ZEV Technology Symposium to learn about the status of ZEV technologies and investigated infrastructure as part of the 2009 ZEV program review. (Documents available by request)
2007- 2008	2008 Regulatory Activities \| Staff went to the Board in early 2007 with the information gathered from the 2006 ZEV Technology Symposium and the report from the Independent Expert Review Panel. The Board recommended changes to the regulation for the 2009 and subsequent model years. The Board approved modifications to the regulation at the March 27, 2008, hearing. The Board also directed staff to redesign the ZEV program for 2015 and subsequent model years. OAL approved the final 2008 rulemaking and filed it with the Secretary of State on March 18, 2009. The regulation became effective on April 17, 2009.
2006	CARB held a technology symposium in 2006, and an Independent Expert Review Panel submitted their report on the status of all ZEV technologies. (Documents available by request). Manufacturers Advisory Correspondence (MAC) 2006-02 for fast refueling capability criterion and advanced technology demonstration applications is available by request.
2003	2003 Regulatory Activities \| Due to a lawsuit filed against the Board in January 2002, a federal district judge issued a preliminary injunction that prohibited the Board from enforcing the 2001 ZEV amendments with respect to the sale of new motor vehicles in model years 2003 or 2004. To address the preliminary injunction and better align the program requirements with the status of technology development, staff proposed additional modifications to the ZEV regulation in March 2003. Once the Board adopted the 2003 amendments to the ZEV regulation, the parties to the lawsuits agreed to end the litigation. On February 25, 2004, the Final Regulation Order and Supplement to the Final Regulation Order were approved by OAL and filed with the Secretary of State. The amendments become operative March 26, 2004. Resolution of ZEV Litigation available by request
2001	2001 ZEV Program Rulemaking \| 2001 ZEV Infrastructure Rulemaking \| The 2001 ZEV rulemaking modifications allowed large auto manufacturers to meet their ZEV requirement with 2% pure ZEVs, 2% Advanced Technology Partial Zero-emission vehicles (AT-PZEV) and 6% PZEVs. On May 24, 2002, OAL approved the 2001 regulatory amendments as set forth in the Final Regulation Order adopted April 12, 2002. In addition, the 2001 ZEV regulation amendments regarding treatment of majority-owned small- or intermediate-volume auto manufacturers and infrastructure standardization was approved by OAL and filed with the Secretary of State on June 24, 2002, effective on July 24, 2002.
2000	2000 ZEV Program Review \| As part of the biennial review in 2000, staff reviewed the regulation and proposed appropriate modifications to address issues of ZEV availability, market demand, cost and incentives that would ensure successful ZEV market uptake.
1998	The ZEV mandate was adjusted as part of the biennial review in 1998 to allow partial ZEV, known as PZEV, credits for extremely clean vehicles that were not pure ZEVs. The underlying goal never changed. California remained committed to seeing increasing numbers of ZEVs in the vehicle fleet. Documents available by request: Board Meeting Notice Re: ARB's ZEV Program and ZEV Technologies ZEV Biennial Program Review Staff Report (Dated July 6, 1998)
1996	1996 ZEV Program Rulemaking \| As part of the biennial review, the ZEV mandate was adjusted in 1996 to eliminate the ramp up years, but left in place the 10% ZEV requirement for 2003. The amendments were approved by OAL on January 3, 1997, and became effective the same date.
1990	Zero-emission Vehicle (ZEV) Program \| When CARB first adopted the Low-emission Vehicle regulation in 1990, 10% of new vehicle sales needed to be zero emission to meet tailpipe standards. At that time, the Board required that in 1998, 2% of the vehicles that large auto manufacturers produced for sale in California had to be ZEVs, increasing to 5% in 2001 and 10% in 2003.