Start Your California Climate Disclosure Journey

Whether you're navigating scope 1–3 emissions or climate risk disclosures, we help businesses comply with SB 253 & SB 261 and reduce reporting risk. Fill in the form to start your compliance roadmap.

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SB 253 — Climate Corporate Data Accountability Act

By August 10, 2026, covered entities must annually disclose their scope 1 and scope 2 GHG emissions. Beginning in 2027, these disclosures are subject to limited assurance, and reporting expands to include scope 3 emissions. By 2030, scope 1 and scope 2 disclosures are required to meet reasonable assurance, and companies must obtain limited assurance for scope 3 emissions.

SB 261 — Climate-Related Financial Risk Act

Originally due January 1, 2026, covered entities must biennially publish a climate-related financial risk report describing climate-related financial risks and related risk mitigation/adaptation measures, using a recognized framework (e.g., TCFD or ISSB/IFRS S2) and making it publicly accessible as well as submitted to CARB's public docket.

Do you need to disclose?

An entity is required to disclose under California climate disclosure laws if all of the following criteria are met:

Revenue Threshold (Fiscal Year Global Revenue)

SB 253: Greater than $1 billion in annual global revenue
SB 261: Greater than $500 million in annual global revenue
*Applicability is determined based on the lesser of the entity's two previous fiscal years of revenue.

Doing Business in California

The entity meets California “doing business” requirements, if any of the following conditions are met during any part of a reporting year:

1. Entity is organized or commercially domiciled in California

2. California sales exceeding $735,019

*If adopted, as proposed, this definition does not include property holdings and payroll. CARB staff stated in the November 18, 2025 public workshop that California sales can be verified using an entity’s filings with the California Franchise Tax Board.

Entity Type

The organization is a U.S. based public or private company

How Ramboll Can Help

Ramboll guides organizations with tailored solutions to ensure compliance:

Regulatory Advisory - Compliance strategy and regulatory monitoring
Scope 1, 2 and 3 GHG Emissions - Preparing audit-ready GHG emission inventories and documentation to meet assurance standards
GHG Verification Support - Providing GHG emissions verification support to meet assurance requirements
Climate Risk and Opportunity Assessment - Evaluating physical and transition risks and opportunities

Start your Compliance Journey here

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When is the first report due?

The initial report for SB 261 (Financial Risk) is due on January 1, 2026^*. For SB 253 (Emissions), the first reports for Scope 1 & 2 are expected by August 10, 2026, followed by Scope 3 reporting in 2027. The California Air Resources Board (CARB) aims to release draft regulations on October 14, 2025, initiating a 45-day public comment period, with final regulations anticipated February 2026.
^*Note: CARB issued an Enforcement Advisory on December 1, 2025 clarifying that reports are voluntary at this time pending January 9, 2026 Court appeal hearing. CARB will provide an alternate date for reporting after the appeal is resolved.

Is third-party verification required?

“Limited assurance” is optional for the first report (due in 2026) and mandatory starting in 2027 (based on FY2026 data) . Limited Assurance will apply for Scope 1 and 2 starting in 2026. This entails a formal audit process that evaluates factors such as sampling plans, data management systems, and compliance with standards like AT-C 210 (AICPA) or ISO 14064-3 (ISO).

Will reporting under ISSB/CSRD be accepted?

Not automatically. You must adhere to California's specific requirements, which include mandatory Scope 3 reporting and assurance. While global reports can serve as a foundation, it's essential to address any compliance gaps.

What is our biggest risk right now?

The primary risk is delay. With the first reporting deadlines approaching in 2026, the collection and assurance of data will require a lead time of 12 to 18 months, particularly for complex Scope 3 data. Additionally, there will be yearly penalties for non-compliance.

What is the immediate priority?

Begin data collection immediately. Ensure that every compliance step is documented—a "good faith effort" can serve as your best defense against potential penalties.

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