What is SB 253?

Climate Corporate Data Accountability Act

California has passed two new laws requiring businesses to disclose their carbon emissions and climate-related financial risks. The Climate Corporate Data Accountability Act (Senate Bill 253) requires large businesses operating in California to publicly report their greenhouse gas emissions. A similar bill, The Climate-Related Financial Risk Act (Senate Bill 261) mandates that companies disclose the threats they face as a result of climate change, and is discussed in more detail here. 

SB 253 Scope

SB 253 requires both public and private US businesses with revenues greater than $1B USD doing business in California to report their emissions comprehensively, including scopes 1, 2, and 3, beginning in 2026 (for 2025 data). SB 253 also requires reporting companies to get third-party assurance of their reports.

An organization is subject to SB 253 if it meets both of the following:

1. Does business in California

• This includes any company with operations, sales, or other commercial activities in the state.

2. Has total annual revenues exceeding $1 billion (USD)

• Revenue is measured globally, not just within California or the U.S.

• Applies to both public and private companies.

SB 253 Reporting

Companies must annually disclose their greenhouse gas (GHG) emissions, specifically:

1. Scope 1 emissions – Direct emissions from owned or controlled sources (e.g., company vehicles, onsite fuel combustion).

2. Scope 2 emissions – Indirect emissions from purchased electricity, steam, heating, and cooling.

3. Scope 3 emissions – All other indirect emissions in a company’s value chain (e.g., supplier emissions, business travel, product use).

Key requirements:

• Scope 1 & 2 disclosures begin in 2026, covering 2025 data.

• Scope 3 disclosures begin in 2027, covering 2026 data.

• Reporting must follow the GHG Protocol standards.

• Emissions must be verified by an independent assurance provider (limited assurance initially, reasonable assurance required later for Scope 1 & 2).

• Disclosures must be made available on a digital public platform designated by the California Air Resources Board (CARB).

SB 253 Assistance

Danesmead Advisory has extensive experience support clients with TCFD reporting (the framework that SB 253 is based on). We can do this on a fully outsourced basis, or on a review basis. We provide tooling to streamline data gathering and reporting, can provide examples of our work on request.

If you’d like to know more about SB 253, whether your organisation is in scope, or would like to understand whether Danesmead Advisory can help, just get in touch.