California's landmark climate disclosure law is active. Starting in 2026, large companies must report Scope 1, 2 & 3 emissions annually. If you supply California-based buyers, Emissa handles your complete emissions inventory — audit-ready and verification-documented.
California SB 253 (the Climate Corporate Data Accountability Act) is the most comprehensive state-level climate disclosure law in the US. While it directly targets companies with over $1 billion in annual revenue, the supply chain pressure it creates reaches mid-market manufacturers — including you.
These are your buyers. Starting with the 2025 fiscal year, California-based companies over $1B revenue must publicly disclose Scope 1, 2, and 3 emissions annually — including supply chain emissions from their Tier 1 suppliers. If you supply Costco, Target, Kroger, or any major California-based retailer, they will ask you for this data.
Even if you're below the $1B threshold, buyer mandates cascade down. Major retailers sourcing from California are implementing supplier Scope 3 disclosure requirements now — ahead of the regulatory deadline. If you don't have a CA SB 253-ready emissions inventory, you risk being flagged in buyer sustainability assessments and losing RFP eligibility.
All fuel combustion, on-site natural gas, fleet vehicles, and refrigerant losses must be inventoried and reported. Emissa connects to your operational data sources — fuel cards, utility records — and produces a complete, verified Scope 1 inventory with EPA factor documentation.
Electricity, steam, heating, and cooling purchased from utilities. CA SB 253 requires both location-based and market-based Scope 2 calculations. Emissa uses EPA eGRID regional factors for location-based accounting and tracks renewable energy certificates for market-based reporting.
⚡ Key deadline: Large companies begin reporting in 2026 for the 2025 fiscal year. Buyer mandates typically cascade 12–18 months ahead of regulatory deadlines. If you're supplying California buyers, your data request is already coming.
Emissa generates the GHG Protocol-aligned emissions inventory CA SB 253 requires — from your QuickBooks export to a complete, verified submission package.
Upload your QuickBooks transaction export, utility bills, and fleet fuel records. Emissa maps every GL code to the correct GHG Protocol Scope 3 category and applies EPA emission factors (eGRID, GHGRP, USEEIO v2.0) across all three scopes.
Select your CA SB 253 reporting scope. Emissa produces a Scope 1, 2, and 3 inventory with all 15 Scope 3 categories covered — including the upstream transportation, purchased goods, and waste categories most relevant to manufacturing suppliers.
CA SB 253 requires third-party verification for large companies. Emissa's output includes methodology documentation, factor source citations, and a SHA-256 report fingerprint — the documentation depth verification bodies require and buyers increasingly expect.
Your CA SB 253 inventory is also your Walmart Gigaton report, EcoVadis submission, and CDP Climate response. Generate once, deploy across every format — without maintaining separate spreadsheets for each buyer.
What mid-market manufacturers need to know about CA SB 253.
California SB 253 (the Climate Corporate Data Accountability Act) requires US companies with over $1B in annual revenue to disclose Scope 1, 2, and 3 emissions starting in 2026. While the law targets large companies directly, mid-market suppliers to California-based buyers will face cascading disclosure requirements through their buyers' procurement processes — and in some cases, direct applicability if they exceed the threshold.
Large companies ($1B+ revenue) must begin reporting in 2026 for the 2025 fiscal year. Mid-market suppliers should prepare now — buyer sustainability mandates typically cascade 12–18 months ahead of regulatory deadlines. If you supply Walmart, Costco, Target, or any major California-based retailer, expect a Scope 3 data request before the regulatory deadline hits.
Yes. CA SB 253 requires Scope 1, 2, and 3 emissions disclosure, including all 15 GHG Protocol Scope 3 categories. This is the most complex part — it requires supply chain spend mapping, transportation data, waste records, and business travel data. Emissa handles all of it from your QuickBooks export.
Emissa generates a complete GHG Protocol-aligned emissions inventory covering Scope 1, 2, and 3 — the exact data CA SB 253 requires. The output includes factor sourcing, methodology documentation, and a SHA-256 report fingerprint for verification. You can submit this directly or use it to respond to buyer data requests as the deadline approaches.
Partially. If you're already generating Scope 1, 2, and 3 totals for Walmart or EcoVadis, those numbers can feed into your CA SB 253 submission. But CA SB 253 has specific verification and attestation requirements beyond what buyers currently demand. Emissa's output is designed to be reusable across multiple formats — you generate once, use across Walmart, EcoVadis, and CA SB 253 simultaneously.
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