California climate disclosure: What to know about CARB reporting

CARB reporting doesn’t have to be complicated; below is a quick guide to demystify the process.

California’s climate disclosure laws, SB 253 and SB 261, require companies that meet defined thresholds to report greenhouse gas emissions (GHG) and climate-related financial risks.

• SB 253 mandates full-scope emissions reporting.
• SB 261 focuses on financial exposure to climate impacts across operations and supply chains.

Who is required to comply with CARB reporting regulations?

U.S.-based public or private companies “doing business” in California — defined as having sales, employees or assets in California.

• SB 253: Companies with over $1 billion in annual global revenue.
• SB 261: Companies with over $500 million in annual global revenue.¹

What are the key deadlines for submitting your report?

• December 1, 2025 SB 261: California Air Resources Board (CARB) opened online submission portal
• January 1, 2026 SB 261: Companies voluntarily submitted first climate-related financial risk reports
• August 10, 2026 SB 253: Scope 1 & 2 emissions disclosures with limited assurance to be reported annually
• 2027 SB 253: Scope 3 emissions disclosures with limited assurance to be reported annually
• 2030
  SB 253: Reasonable assurance for Scope 1 & 2, limited assurance for Scope 3

How do businesses file their climate disclosure reports?

Companies subject to these regulations can submit their reports via digital platforms provided by the CARB, which are available on their program page.

For SB 261, CARB allows entities to use one of three frameworks when reporting on climate-related financial risks:

• Task Force on Climate-related Financial Disclosures (TCFD) recommendations.
• International Financial Reporting Standards (IFRS) S2
• A report aligned with a regulated exchange or government entity.

Disclosures must include a summary that identifies the chosen framework, any omissions and the rationale for those omissions.

What specific data and metrics do you need to include?

Reports for SB 253 must include Scope 1 & 2 and eventually Scope 3 emissions. First submissions require limited assurance, but over time will require reasonable assurance. See the timeline above for details.

SB 261 requires disclosure of climate-related financial risks and strategies for mitigation and adaptation. However, companies are not required to conduct quantitative scenario analyses or report Scope 1, 2 or 3 emissions under the Metrics and Targets section, allowing flexibility in how risks are assessed and communicated. See the checklist on this page for the minimum SB 261 requirements.

What happens if you don’t comply with CARB regulations?

The penalties for noncompliance with CARB reporting requirements by a qualifying entity are as follows for each bill:

• SB 253: Up to $500,000 per year for noncompliance (e.g., non-filing or late submissions).
• SB 261: Enforcement of SB 261 has been paused pending a court injunction. However, over 120 companies have voluntarily submitted SB 261 reports which can be found on CARB’s website.

1. Enforcement of SB 261 is currently paused due to a Ninth Circuit injunction.