# California SB 253 Readiness Checklist

**Version 1.0 · Published by OffGridFlow · April 14, 2026**

A practical checklist for companies preparing their first California Senate Bill 253 (Climate Corporate Data Accountability Act) disclosure. Use it to identify gaps before the CARB filing window opens.

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## 1. Scope Determination

- [ ] Confirmed total annual revenue exceeds $1 billion USD
- [ ] Confirmed meaningful business activity in California
- [ ] Identified all consolidated subsidiaries in scope
- [ ] Determined reporting fiscal year (first Scope 1 & 2 year)
- [ ] Determined first Scope 3 reporting year

## 2. Governance and Ownership

- [ ] Assigned executive sponsor (CFO or equivalent)
- [ ] Named day-to-day owner (sustainability lead, controller, or equivalent)
- [ ] Identified backup owner for continuity
- [ ] Board or audit committee briefed on SB 253 obligation
- [ ] Internal controls owner identified (SOX-adjacent where applicable)

## 3. Methodology Selection

- [ ] Selected calculation methodology (GHG Protocol recommended)
- [ ] Documented methodology version internally
- [ ] Chosen Scope 2 methods (location-based required; market-based if applicable)
- [ ] Scope 3 tier strategy defined (spend-based / activity-based / supplier-specific per category)
- [ ] Factor source pack documented (EPA eGRID, IEA, DEFRA, IPCC)

## 4. Data Collection

- [ ] Activity data inventory complete for Scope 1
  - [ ] Stationary combustion (boilers, generators, furnaces)
  - [ ] Mobile combustion (company fleet)
  - [ ] Fugitive emissions (refrigerants, natural gas leaks)
  - [ ] Process emissions (industrial)
- [ ] Activity data inventory complete for Scope 2
  - [ ] Purchased electricity by facility
  - [ ] Purchased steam, heating, cooling
  - [ ] Contractual instruments (RECs, PPAs, green tariffs) for market-based
- [ ] Scope 3 source inventory by category
  - [ ] Purchased goods and services spend
  - [ ] Capital goods spend
  - [ ] Business travel records
  - [ ] Employee commuting estimates
  - [ ] Waste tonnage by treatment type
  - [ ] Value chain transport
  - [ ] (... remaining 9 categories as material)

## 5. Calculation Infrastructure

- [ ] Calculation tool selected and procured
- [ ] Calculation ledger available for audit trail
- [ ] Factor snapshot lockable for the reporting period
- [ ] Immutable change log for any data edits
- [ ] Approval workflow with preparer / reviewer / approver separation

## 6. Quality Assurance

- [ ] Anomaly detection in place (outliers, duplicates, sudden changes)
- [ ] Data quality tier tagged per Scope 3 category
- [ ] Year-over-year reconciliation process documented

## 7. Assurance Readiness

- [ ] Independent assurance provider selected
- [ ] Scope 1 & 2 limited assurance engagement letter signed
- [ ] Evidence pack format aligned with provider requirements
  - [ ] Source activity records
  - [ ] Factor provenance and version
  - [ ] Calculation ledger extract
  - [ ] Approval trail
  - [ ] Export reconciliation checksum
- [ ] Scope 3 assurance strategy (even if not yet mandatory, anticipate escalation)

## 8. Filing Readiness

- [ ] Draft disclosure package produced per CARB guidance
- [ ] Internal review completed (finance + sustainability + legal)
- [ ] Board review scheduled
- [ ] Assurance provider sign-off received
- [ ] Filing submitted on or before CARB deadline
- [ ] Filing reference retained for prior-year reconciliation

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## Notes

- This checklist is a working aid, not legal advice. Customers remain responsible for determining SB 253 applicability, interpreting CARB guidance, and ensuring the final disclosure meets regulatory requirements.
- OffGridFlow is calculation and reporting software. This checklist references what a carbon accounting tool should make easy (immutable ledger, factor snapshot, approval workflow) — any tool that cannot produce these artifacts will struggle under assurance.
- Questions: contact@off-grid-flow.com

Download this checklist as part of the public evidence pack at https://off-grid-flow.com/evidence.