CARB published the 2026 State Implementation Plan (SIP) Revisions for California Extreme Ozone Nonattainment Areas. The SIP revisions address federal Clean Air Act requirements for areas not meeting the 75 ppb ozone National Ambient Air Quality Standard, including motor vehicle emissions budgets and control strategies.
CARB issued a 15-day notice for the Proposed California Corporate Greenhouse Gas Reporting and Climate-Related Financial Risk Disclosure Initial Regulation. The notice follows the Board's February 26, 2026 approval and includes modified text for sections 96070-96077, Title 17, California Code of Regulations. The regulation establishes a fee program, first-year reporting deadline for Health and Safety Code section 38532, and key definitions. Public comments are due by August 11, 2026.
CARB posted the Third Notice of Public Availability of Modified Text for proposed amendments to the On-Road Heavy-Duty Engine and Vehicle Omnibus regulations, Low Carbon Fuel Standard regulations, and permanent adoption of Emergency Vehicle Emissions Regulations. The comment deadline for the Third 15-Day Changes is August 5, 2026. This rulemaking proceeding addresses amendments to multiple CARB mobile source and fuel programs. Previous 15-day notices were posted April 3, 2026 (first) and June 30, 2026 (second).
CARB announced a proposed three-month deferral of the first-year reporting deadline for Scope 1 and Scope 2 greenhouse gas emissions under the Climate Corporate Data Accountability Act (SB 253). The original August 10, 2026 deadline would be extended to November 10, 2026. This change is proposed as part of a 15-day modification to the Initial Regulation, which was withdrawn from the Office of Administrative Law to make limited clarifying changes. CARB indicated it will use enforcement discretion for good-faith first-year submissions.
The California Air Resources Board permanently adopted the Emergency Vehicle Emissions Regulations that were initially adopted in 2025 as a temporary measure after the federal government purportedly disapproved California's waivers for newer vehicle emissions regulations, including Advanced Clean Cars II (ACC II) and Heavy-Duty Engine and Vehicle Omnibus (Omnibus). The amendments clarify that California's earlier vehicle emission standards remain in effect. Manufacturers may continue to seek CARB certification to pre-ACC II/Omnibus standards, may voluntarily comply with ACC II/Omnibus requirements, and voluntary compliance provides regulatory certainty and may benefit state procurement preferences. California is challenging federal actions in court.
OEHHA released draft cancer risk assessments showing acrolein and ethylene oxide can potentially pose unacceptable cancer risks exceeding 800 in 1 million, more than 10 times higher than benzene. Governor Newsom proposed $2.5 million for expanded air monitoring and research. Public workshops scheduled for June 2, 2026 (Sacramento) and June 4, 2026 (Los Angeles) with a 45-day public comment period.
The California Air Resources Board adopted comprehensive updates to the state's Cap-and-Invest Program (formerly Cap-and-Trade), extending it through 2045 following legislative authorization through SB 840 and AB 1207 in 2025. The adopted changes maintain California's path toward meeting 2030 and 2045 climate targets while supporting affordability for Californians. The program covers approximately 80% of California's climate emissions and has achieved nearly 100% compliance over 13 years of operation. The updates balance legislative direction, affordability, jobs and near-term economic concerns while ensuring emissions reductions and providing long-term market signals for clean energy investment. Estimated compliance cost is $124 billion over the 20-year lifetime, approximately $20 billion less costly than scenarios analyzed in April 2024.
The CARB Board adopted amendments to the Regulation for the Mandatory Reporting of Greenhouse Gas Emissions via Resolution 26-6 at its May 28, 2026 meeting. The amendments include clarifications on cessation, emissions and product data reporting requirements, and definitions to support accurate and complete GHG accounting and the Cap-and-Invest Program. The amendments also address potential emissions leakage from imported electricity transfers within CAISO's Western Energy Imbalance Market, including anticipated Extended Day Ahead Market transactions. These changes harmonize MRR reporting with the Cap-and-Invest and Low Carbon Fuel Standard programs.
CARB has an active rulemaking for Proposed 2026 Amendments to the Cap-and-Invest Regulation (California Cap on Greenhouse Gas Emissions and Market-Based Compliance Mechanisms). The program and docket materials indicate defined public participation steps (public hearing and public comment opportunities) for stakeholders affected by allowance market design and compliance obligations. Compliance teams for covered entities, offset/market participants, and regulated facilities should monitor the docket for adopted regulatory text, final timelines, and any transition provisions.
CARB has proposed 2026 amendments to the Regulation for the Mandatory Reporting of Greenhouse Gas Emissions. The Board held a public hearing on May 28-29, 2026 (Resolution 26-6). The MRR was originally approved in 2007 and revised in 2010, 2012, 2013, and 2018. Covered entities should monitor the rulemaking for changes to reporting requirements.
CARB adopted updates to California's Cap-and-Invest Program extending it through 2045, implementing long-term allowance budgets beyond 2030, transferring free allowances from natural gas to electric utilities, maintaining industry free allowances, and enhancing market manipulation protections. The updates include post-2030 allowances added to the Allowance Price Containment Reserve. Estimated compliance costs are $124 billion over 20 years with projected benefits of $180.7 billion statewide.
CARB opened the formal hearing/comment process for proposed amendments to the California Cap on Greenhouse Gas Emissions and Market-Based Compliance Mechanisms Regulation (Cap-and-Invest). CARB posted the Notice of Public Hearing and the Proposed Regulation Order (proposed regulatory text), along with CEQA documentation including a Final Environmental Impact Analysis (EIA) dated May 26, 2026. Covered entities and market participants should track the proposed regulatory changes and participate in the hearing/comment process as applicable.
CARB published an updated Auction Notice for the California Cap-and-Invest Program and Québec Cap-and-Trade System Joint Auction (#47) scheduled for May 20, 2026. The notice update (issued May 15, 2026) provides current auction logistics and schedule details relevant for approved bidders and compliance entities relying on auctions for allowance acquisition planning.
CARB has proposed amendments to the Regulation for the Mandatory Reporting of Greenhouse Gas Emissions. The proposed amendments target revisions to clarify how entities report GHG emissions to support the Cap-and-Invest Program, ensure data accuracy, expand program applicability, and incorporate new fuel pathways and technologies.
CARB extended the public comment deadline to May 4, 2026 for the Notice of Public Availability of Modified Text (15-day Amendments) to the Proposed Amendments to the Regulation for the California Cap on Greenhouse Gas Emissions and Market-Based Compliance Mechanisms. The original deadline was extended to provide stakeholders additional time to review and comment on the modified regulatory text. Regulated entities and stakeholders should submit comments by the new deadline.
CARB issued a Notice of Public Availability of Modified Text (15-Day Amendments) for proposed amendments to the Regulation for the California Cap on Greenhouse Gas Emissions and Market-Based Compliance Mechanisms. The public availability date is April 14, 2026, with the deadline for public comment extended to May 4, 2026. The public hearing was scheduled for May 28, 2026.
CARB published a Notice of Public Availability of Modified Text ("15-day changes") for proposed amendments to the Advanced Clean Fleets (ACF) and Low Carbon Fuel Standard (LCFS) regulations. The notice summarizes proposed adjustments including removal of ePTO-related definitions/requirements (because related provisions were removed), definitional updates (e.g., good engineering judgement; Low-NOx ICE Vehicle), added flexibility to switch between ACF compliance options (ZEV Milestones vs. ZEV Purchase Schedule) until January 1, 2030 (with conditions), and revisions to ZEV purchase schedule timing (including language described as delaying a 100% ZEV purchase requirement from 2027 to 2030 for certain fleets). The notice also states that the Sept. 25, 2025 Board action repealed certain ACF fleet requirements (Drayage, High Priority, and Federal Fleet requirements). Compliance teams for affected fleets/fuel program participants should review the modified text and submit comments within the 15-day window.
CARB published new Frequently Asked Questions (FAQ) to assist regulated entities with implementation of the 2025 LCFS amendments. The FAQ addresses sustainability requirements under new subsection 95488.9(g), feedstock supplier compliance timelines, and other implementation questions following amendments that came into effect July 1, 2025.
CARB’s emergency vehicle emissions rulemaking page indicates the Office of Administrative Law (OAL) approved the first readoption of the emergency vehicle emissions regulations and that the readoption was filed with the Secretary of State on March 26, 2026. CARB states the readopted emergency regulations become effective April 1, 2026 and will expire July 1, 2026. Compliance teams impacted by these emergency vehicle emissions provisions should account for the operative window through July 1, 2026 and monitor subsequent readoptions or permanent rulemaking.
The California Air Resources Board (CARB) approved amendments to the Advanced Clean Trucks (ACT) regulation and Zero-Emission Powertrain (ZEP) Certification standards. The amendments provide flexibility for manufacturers in meeting zero-emission truck sales requirements while maintaining emissions benefits. The ACT regulation requires truck manufacturers to sell zero-emission vehicles as an increasing percentage of their California sales, and ZEP Certification establishes standards for zero-emission powertrain certification.