SB 253 Reporting Requirements: Deadline and What's Next

Two filings satisfy today's deadline. One is a Scope 1 and Scope 2 emissions report. The other is a statement on company letterhead explaining that you are not submitting one.

Which route you are entitled to use was fixed on 5 December 2024, the date the California Air Resources Board issued its Enforcement Notice. If your company was collecting Scope 1 and 2 data then, or planned to, the report is the answer. If it was neither collecting nor planning to, the letter is. Nothing has changed since that test, which means the decision available today was settled almost two years ago.

Everything else about this filing is live, and two details are worth knowing before anything is uploaded: the submission becomes public, and the fee arrives no matter which route you take.

What Is Due Today

California's Office of Administrative Law approved the Initial Regulation on 12 October 2026, and it took effect the same day. CARB had first approved it on 26 February 2026, then withdrew it from review to clarify requirements. It is codified at Title 17, California Code of Regulations, sections 96070 to 96077.

The regulation does four things: sets the first-year Scope 1 and Scope 2 reporting deadline of 10 November 2026, moved from 10 August; defines which entities are covered by SB 253 and by SB 261; sets recordkeeping requirements; and establishes an annual fee framework.

Submission goes through CARB's 2026 Report Intake Platform or by email to the climate disclosure address. Use of the platform is not mandatory.

CARB has said it will accept several formats: an existing annual report that already contains Scope 1 and 2 figures, data already reported to another program or voluntary initiative, or CARB's draft Scope 1 and 2 template released in October 2025. It encourages supporting detail, including methodologies, data sources, global warming potential values, emission factors, organizational boundaries, disaggregated data by category and gas, and assumptions.

Who Is Covered

Three tests, and all three have to be met.

Formation. The entity must be formed under United States law. That includes a US subsidiary of a foreign parent, which is the point most often missed by groups headquartered elsewhere.

Revenue. More than $1 billion in total annual revenue, measured globally rather than on California activity. The test uses the lesser of the two most recent fiscal years, so a single strong year does not pull a company into scope on its own.

Doing business in California. The entity must engage in a transaction in the state for financial or pecuniary gain, and either be organized or commercially domiciled in California, or have California sales above $735,019 for 2024 or $757,070 for 2025. Physical presence in the state is not required.

For a corporate group, the analysis runs at the entity level, not the group level. You need the consolidated reporting perimeter and a separate answer on whether each entity independently meets the applicability criteria.

Which Fiscal Year To Report

The reporting year turns on your fiscal year end, and the rule is narrow enough to get wrong.

A fiscal year ending between 1 January and 1 February 2026 uses the fiscal year ending in 2026. A fiscal year ending between 2 February and 31 December 2026 uses the fiscal year ending in 2025, with more recent data permitted if it is available.

So most December year-end filers are reporting fiscal 2025 figures today, not 2026.

The Letterhead Route And The December 2024 Test

CARB's position is that a company that was not collecting Scope 1 and 2 data, and did not plan to collect it, when the 5 December 2024 Enforcement Notice was issued, is not required to submit emissions data in 2026. CARB asks such a company to submit a statement of non-reporting on company letterhead before 10 November.

For everyone else, the first-year accommodation is different and narrower. Companies may rely on information they possessed or were already collecting as of 5 December 2024, and CARB has said it will not take enforcement action against incomplete reporting when a company acts in good faith. It also expects entities to submit the information they do have.

Read those two together, and the structure is clear. The letter is for companies that had nothing in train at the end of 2024. The good-faith allowance is for companies that had something and cannot yet produce everything. A company in the second group that files a letter rather than partial data has chosen the wrong route.

One practical consequence. Because the test is retrospective, the supporting evidence is historical: what your data collection looked like in late 2024, and who can attest to it. If you are taking the letterhead route, document that position now rather than when somebody asks.

What The Platform Asks That The Guidance Does Not

The intake platform requests information the published guidance does not mention, which is a problem if you drafted the submission from the guidance alone.

It asks up front how many reporting entities the submission covers, and whether fees will be paid combined or individually. It then opens a block per entity requesting the full legal name as filed on tax forms, an identifier such as a federal EIN, California Corporation Number, or Secretary of State file number, and the California Principal Business Activity code from the entity's state tax filing.

Consolidated reporting is accepted. Consolidated identification is not. There is no line for a group and its subsidiaries, so each covered entity has to be named and identified separately even where one report covers them all.

A single submission may mix the two routes, carrying emissions reports for some entities and statements of non-reporting for others.

Then the detail that deserves a pause before anybody clicks upload. The platform states that uploaded reports and statements will be made public, and the workflow offers no confidentiality designation and no redaction option. Anything confidential has to come out of the document before it goes in. A report assembled for internal use, or an extract from a board paper, is not automatically safe to submit.

Assurance, Fees And Penalties

On assurance, today's position is simpler than much commentary suggests. The Initial Regulation leaves independent third-party assurance to a later rulemaking, and CARB has said it will accept 2026 submissions whether or not limited assurance has been obtained. Assurance over Scope 1 and 2 is expected to arrive with the 2027 cycle, with CARB signaling a move to reasonable assurance by 2030.

On fees, annual fees begin in 2026, a nd the regulation sets the framework rather than publishing an amount here. CARB is expected to notify companies of what they owe by 10 December 2026, with payment due within 60 calendar days of that notice, on the latest notification date, that puts payment around 8 February 2027, which is worth putting in the finance calendar now rather than treating as a problem for next year.

Two points about how fees attach. They apply per reporting entity rather than per group, though a parent may pay a combined amount. They apply to every covered entity regardless of whether it submits emissions data or a statement of non-reporting. Taking the letterhead route avoids the data, not the fee.

The maximum administrative penalty is $500,000 per reporting year.

What Comes Next

Three things, on different tracks.

Scope 3. CARB expects Scope 3 disclosure to begin in the 2027 cycle, covering 2026 emissions. The regulations are still being developed, which means the boundary and category decisions a company needs to prepare are not yet settled. Start from the categories you can already evidence from procurement and logistics records rather than waiting for the rule.

Assurance. Also in 7, and through future rulemaking, limited assurance over Scope 1 and 2 is expected. An assurance provider will want the 2026 figures to be reproducible, so retain the working papers behind today's submission even though nobody is assuring it. The Initial Regulation imposes recordkeeping requirements in its own right, which makes that retention an obligation rather than a precaution.

SB 261. The Ninth Circuit temporarily enjoins the companion biennial climate-risk reporting requirement, and the litigation challenging it continues. That injunction does not extend to SB 253, which is why today's deadline stands. Plan the two separately, because their legal positions differ.

If You Are Filing Today

Four checks, in order.

Confirm which route you are entitled to use based on your position in December 2024, not your position now.

Confirm the fiscal year. If your year ends in December, you are almost certainly reporting fiscal 2025.

Open the document you intend to upload and read it as a public filing, because that is what it becomes. Remove anything you would not publish.

And gather, for each covered entity, its full legal name as filed on tax forms, its EIN or California identifier, and its California Principal Business Activity code. That list is what the platform asks for, and it is the step most likely to stall a submission in the last hour.

Position as of 10 November 2026, the filing date itself. The Initial Regulation's approval and effective date, its codification at Title 17 sections 96070 to 96077, the covered-entity tests, the fiscal year rule, the letterhead route, the fee and penalty points, and the platform's additional fields are drawn from law firm and accounting firm analyses of CARB's regulation and guidance and of its reporting platform, not from the regulation or the platform directly; confirm each against the regulation text, CARB's current guidance,e and the platform itself before filing. Sources consulted differed on whether limited assurance applies to the 2026 submission; the position stated here follows the account that the Initial Regulation defers assurance to a later rulemaking and that CARB will accept 2026 submissions without it, and anyone relying on that should verify it with CARB or counsel. Revenue and sales thresholds, fee mechanics, notification dates and penalty amounts are as reported and may be superseded. Whether a particular entity is covered is a legal determination that depends on facts not addressed here. The SB 261 injunction and the related litigation are ongoing, ng and the position may change. Nothing in this article is legal, accounting, tax, or assurance advice, and filing decisions should be taken with qualified advisers.