California Greenhouse Gas Reporting Update: CARB Defers 2026 Reporting Deadline and Announces Upcoming Regulatory Changes
June 26, 2026
On June 24, 2026, the California Air Resources Board (CARB) announced it is delaying the initial reporting deadline for Scope 1 and Scope 2 greenhouse gas (GHG) emissions under the California Corporate Greenhouse Gas Reporting Program established under Senate Bill 253 (SB 253) from August 10, 2026 to November 10, 2026. Additionally, CARB will soon propose limited changes to its SB 253 implementing regulations that CARB says will clarify certain reporting requirements. This alert summarizes these developments and their practical implications for companies subject to SB 253.
Key Takeaways:
- 2026 reporting deadline deferred: CARB is deferring the deadline for reporting Scope 1 and Scope 2 GHG emissions from August 10, 2026 to November 10, 2026, giving reporting entities an additional three months to prepare their reports.
- Regulatory clarifications forthcoming: CARB will propose limited changes to its SB 253 implementing regulations to clarify certain reporting requirements and will release the proposed changes for a 15-day public comment period.
- Scope 3 reporting still on track to begin in 2027: While the 2026 reporting deadline for Scope 1 and Scope 2 emissions will be delayed, there has been no change to companies’ obligations to begin disclosing Scope 3 emissions starting in 2027.
SB 253 requires US-based companies with total annual revenues exceeding US$1 billion that do business in California to annually disclose their Scope 1, Scope 2, and Scope 3 GHG emissions. CARB proposed its draft SB 253 implementing regulations in February 2026, which contemplated an initial reporting deadline of August 10, 2026.
On June 24, 2026, CARB announced it will modify its draft regulations to delay the initial reporting deadline for Scope 1 and Scope 2 GHG emissions from August 10, 2026 to November 10, 2026. CARB states the three-month delay is designed to give reporting entities additional time to ensure compliance following final adoption of the regulations.
In addition to the deadline extension, CARB will propose limited changes to the draft regulations to clarify certain reporting requirements. CARB has not yet identified these additional changes, which will be made available for review as part of a forthcoming 15-day public comment period. CARB will resubmit the regulations for finalization following the public comment period.
Companies subject to SB 253 should continue preparing for Scope 1 and Scope 2 reporting this year and for Scope 3 reporting next year, though the future of SB 253 remains uncertain due to ongoing litigation in the Ninth Circuit over the law’s constitutionality (as discussed in our prior Alert).
We will continue to monitor developments related to California’s Corporate GHG Reporting Program and provide updates.
This memorandum is a summary for general information and discussion only and may be considered an advertisement for certain purposes. It is not a full analysis of the matters presented, may not be relied upon as legal advice, and does not purport to represent the views of our clients or the Firm. Eric Rothenberg, an O'Melveny of counsel licensed to practice law in New York and Missouri; John D. Renneisen, an O’Melveny senior counsel licensed to practice law in the District of Columbia; Chris Bowman, an O’Melveny counsel licensed to practice law in California; and William D. Kosinski, an O’Melveny associate licensed to practice law in California, contributed to the content of this newsletter. The views expressed in this newsletter are the views of the authors except as otherwise noted.
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