Climate Disclosure & Assurance Readiness
California SB 253 reporting begins in 2026. Investor and customer expectations for climate data continue regardless of federal requirements.
The disclosure landscape
California’s Climate Corporate Data Accountability Act (SB 253) requires US entities with over $1 billion in annual revenue doing business in California to report Scope 1 and 2 greenhouse gas emissions beginning in 2026, with Scope 3 reporting following in 2027. CARB approved initial implementing regulations in February 2026. SB 253 has not been enjoined.
Separately, the SEC proposed rescission of its 2024 climate-related disclosure rules in May 2026, with the public comment period closing in August 2026. California’s SB 261 (climate-related financial risk) is enacted but enforcement has been enjoined by the Ninth Circuit since November 2025.
Regardless of federal outcomes, California requirements, investor expectations, and customer due-diligence requests ensure that rigorous, auditable climate data remains essential for large US companies.
Who this is for
- US entities with over $1 billion in annual revenue doing business in California
- Companies with over $500 million in revenue monitoring SB 261 injunction outcomes
- Companies responding to investor or customer climate-data requests
- Organizations preparing for potential future federal disclosure requirements
What RSustain provides
- California applicability screeningRevenue threshold analysis, entity-structure review, and scope determination under SB 253.
- Organisational and operational boundary reviewApplying GHG Protocol boundary principles to determine reporting perimeter.
- Scope 1 and Scope 2 inventory developmentActivity data collection, emission-factor selection, and calculation-method documentation.
- Scope 3 screening and prioritisationCategory-level screening across all 15 Scope 3 categories to identify material sources.
- Emission-factor and calculation-method registerDocumented register of every factor, source, version, and methodology used.
- Evidence register and data-owner mappingLinking every reported metric to its source document, responsible owner, and review status.
- Internal-control assessmentEvaluating data-collection controls, approval workflows, and error-detection processes.
- Data-quality scoringScoring each data point for completeness, accuracy, timeliness, and auditability.
- Pre-assurance gap assessmentIdentifying gaps that an independent assurance provider would flag before engagement.
- Management review packsBoard-ready summaries of emissions data, methodology, controls, and readiness status.
- Remediation roadmapPrioritized action plan to close identified gaps before the assurance engagement.
Regulatory status (as of July 2026)
| Regulation | Status | Key Date | Note |
|---|---|---|---|
| CA SB 253 | Enacted | Scope 1/2: Aug or Nov 2026 | CARB regs adopted Feb 2026; no injunction |
| CA SB 261 | Enjoined | Original: Jan 1, 2026 | Ninth Circuit stay since Nov 18, 2025 |
| SEC Climate Rule | Proposed Rescission | Comment closes Aug 3, 2026 | Final rescission requires subsequent SEC vote |
Regulatory status as of July 2026. Monitor CARB, Ninth Circuit, and SEC for updates.
Frequently asked questions
Does my company need to report under SB 253?
If your entity has over $1 billion in annual revenue and does business in California, you are likely in scope. SB 219 (2024) permits consolidated parent-level reporting. An applicability screening determines your specific obligations.
What about the SEC Climate Rule?
The SEC proposed complete rescission of its climate-disclosure rules in May 2026. The comment period closes August 3, 2026, and a final rescission would require a subsequent SEC vote. California requirements and investor expectations remain regardless of the federal outcome.
Does RSustain provide independent assurance?
No. RSustain provides advisory and readiness services — preparing your data, controls, and evidence to the standard that an independent assurance provider would test. When assurance is required, it must be performed by an appropriately qualified and independent provider.
What is the difference between readiness and assurance?
Readiness means your data, controls, documentation, and evidence are prepared to withstand independent testing. Assurance is the independent opinion provided by a qualified third party. RSustain delivers readiness; the assurance provider delivers the opinion.