The California Air Resources Board Launches Voluntary Reporting Platform And Issues New Guidance Ahead Of Pending November 10, 2026, SB 253 Reporting Deadline

1. The California Air Resources Board has released 2026 Reporting Guidance outlining final first-year reporting expectations for California’s Climate Corporate Data Accountability Act (SB 253).
2. To facilitate report submissions, CARB has launched a voluntary reporting intake platform where covered entities can submit contact information, billing details, and, optionally, their Scope 1 and Scope 2 emissions data ahead of the expected November 10, 2026, reporting deadline.
3. Entities that were not collecting Scope 1 and Scope 2 emissions data as of December 5, 2024, are not required to generate data for submission for this first cycle but must nevertheless submit a statement of non-reporting on company letterhead.
4. The revised implementing regulation for SB 253—which will impose the November reporting deadline—remains pending OAL approval; however, CARB’s approach assumes reporting will proceed by November 10, 2026. Covered entities should plan accordingly.

On September 1, 2026, the California Air Resources Board (“CARB”) published materials to assist entities preparing for their inaugural greenhouse gas (“GHG”) emissions reports under the Climate Corporate Data Accountability Act (“SB 253”). These materials include targeted reporting guidance for the anticipated November 2026 reporting deadline and a voluntary reporting intake platform (with associated instructional video) intended to streamline submissions. CARB’s reporting guidance acknowledges that its Initial Regulation—which must be finalized for the inaugural SB 253 reporting deadline of November 10, 2026, to take effect—is still pending approval by California’s Office of Administrative Law (“OAL”). CARB’s approach suggests confidence that the Initial Regulation will be approved by OAL in time for the November 10 reporting deadline. Entities that believe they are subject to SB 253 should prepare accordingly to timely submit their inaugural report or statement of non-reporting (as applicable).

2026 Reporting Guidance: Highlights

CARB’s September 1, 2026, California Corporate Greenhouse Gas Reporting: Guidance for SB 253 2026 Reporting Submittals (“2026 Reporting Guidance”), available here, summarizes key information to streamline inaugural SB 263 reporting for covered entities.

CARB reiterates, consistent with its December 5, 2024, Enforcement Notice (here), that it will exercise enforcement discretion in 2026 such that entities are only required to report based on Scope 1 and 2 emissions data that was in their possession or being collected as of December 2024, whether or not the data received limited assurance. CARB’s exercise of enforcement discretion will allow entities that were not collecting emissions data as of December 5, 2024, to submit a “statement of non-reporting” on company letterhead “indicating that they were not collecting data and were not planning to collect data at the time the Enforcement Notice was issued.”

According to CARB, acceptable report formats for 2026 include: (i) existing annual reports containing Scope 1 and 2 GHG emissions data, (ii) existing Scope 1 and 2 data reported to other programs or voluntary initiatives, or (iii) CARB’s voluntary reporting template (posted October 2025).

CARB’s Guidance also highlights the following points regarding data collection and assurance:

• Scope 2 Emissions Factors. No specific emission factor dataset is required for calculation of Scope 2 GHG emissions—entities may use eGRID 2023 or alternative credible sources and should identify the factors and sources used in their report.
• Assurance. SB 253 requires limited assurance of Scope 1 and 2 emissions data beginning in 2026. That said, CARB is accepting submissions for the 2026 cycle whether or not assurance has been obtained.
• Data Detail & Disaggregation. CARB is encouraging reporting entities to provide “additional details” in the first year of reporting, where available. Details CARB is encouraging entities to provide include, but are not limited to, descriptions of methodologies, data sources, global warming potential values, emission factors, organizational boundaries, disaggregated emission data by category and gas, and any assumptions used. Setting aside CARB’s request for the voluntary submission of this information, providing additional details, if available within your organization, may help qualify and provide context for the GHG emissions being reported.

The voluntary reporting intake platform

CARB has developed a voluntary report intake platform to streamline fee implementation and first-year reporting. Entities may also submit data by emailing climatedisclosure@arb.ca.gov. Through the intake platform, entities can: (1) provide contact information to CARB ahead of the November 10 deadline, (2) optionally submit Scope 1 and Scope 2 emissions reports, and (3) provide billing information for fee invoicing. Entities not planning to report emissions in 2026 (consistent with CARB’s December 2024 Enforcement Notice) may also use the platform to notify CARB of that fact. CARB has released an instructional video—“How to Use the 2026 SB 253 Voluntary Reporting Intake Form”—walking users through the submission process.

The broad range of expertise at Hogan Lovells US LLP – including the Environment and Natural Resources, Sustainable Finance and Investment, Corporate and Finance, and Infrastructure, Energy, Resources and Projects teams – are available to assist clients with complying with California’s GHG emissions disclosure requirements under SB 253 and can help you understand interactions with other relevant sustainability-related reporting regimes required globally.

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