The California Air Resources Board (CARB) has published a list of over 4,000 companies that must adhere to the state’s new climate reporting regulations. These laws require disclosures concerning climate-related risks and opportunities, and, for certain companies, value chain greenhouse gas emissions.
The legislation introduces climate-related reporting requirements for most large U.S. companies, even as other climate disclosure regulations, such as the SEC’s climate reporting rule, appear increasingly unlikely to be enacted. The CARB list comprises 4,160 U.S. companies, including most S&P 500 constituents.
Regulations SB 253 and SB 261 were approved by Governor Newsom in 2023 and signed into law in October 2024. SB 253 mandates that companies with revenues exceeding $1 billion conducting business in California annually report their direct Scope 1 and 2 emissions, and Scope 3 emissions, which encompass supply chains, business travel, employee commuting, procurement, waste, and water usage. SB 261 applies to U.S. companies operating in California with revenues over $500 million, requiring them to prepare a report disclosing their climate-related financial risk and measures to mitigate and adapt to that risk.
Disclosures of Scope 1 and 2 emissions under the new law are scheduled to commence in 2026, covering the previous fiscal year, while Scope 3 emissions reporting will begin in 2027. The first climate-related risk reports are to be published by 1 January 2026.
Of the companies listed by CARB, approximately 60% (2,503) are based outside California. The majority (2,596) will be required to comply with both SB 253 and SB 261, while 1,564 will be subject solely to SB 261.
CARB noted that the list is preliminary and may not encompass all companies covered by the new climate-related reporting laws, as it is derived from data as of March 2022. Companies are responsible for reporting under the regulations even if not included on the list. The list may also include companies not required to report under the regulations due to recently released exemptions, such as subsidiary companies if their parent company issues a report on their behalf.
[Click here](https://ww2.arb.ca.gov/sites/default/files/2025-09/SB%20253_261_preliminary_list_092425.xlsx) to access CARB’s list.
