What are the California Climate Regulations (SB 253 and SB 261)?
California’s climate regulations, SB 253 and SB 261, are reshaping emissions transparency requirements for thousands of US companies. These aren’t just rules for California-headquartered businesses. If you do business in the state and meet the revenue thresholds, you’re likely in scope.
Together, they’re the most comprehensive emissions and climate risk disclosure requirements in the country, with real financial penalties for non-compliance.
While SB 261 is currently paused following a Ninth Circuit injunction, SB 253 is very much active for companies who report over $1B in revenue annually. Companies required to report their greenhouse gas emissions face an August 10, 2026 deadline. If you haven’t started building a compliance plan, now is the time.
Why does picking the right vendor matter?
This guide is for companies navigating the vendor market for GHG accounting software ahead of SB 253 compliance. Getting this right matters, and you’ll need a solution that produces accurate Scope 1, 2, and 3 emissions data capable of withstanding regulatory scrutiny, all while remaining transparent, auditable, and easy to use.
For many organizations, this will be their first GHG inventory or first public disclosure of GHG emissions data…and it is with a tight turnaround. It’s a significant undertaking, but absolutely manageable. There are strong vendors to choose from, each with distinct toolsets and areas of expertise.
It’s time to start thinking of a GHG inventory as more than a compliance checkbox. Done well, it’s a strategic asset that can inform business decisions, strengthen customer relationships, and help future-proof your organization.
What should teams look for in a vendor?
- Proven enterprise-grade solution with full auditability baked in
- Full scope 1, 2, and 3 solution with the ability to use activity-based data that gives you credit for performance
- No hidden costs or reliance on third party implementations
- Tools the leverage AI for automation across data ingestion and reporting – saving you time and money
Who are the best vendors for SB 253 compliance?
1. Optera
Optera offers an all-in-one solution for GHG measurement, reporting, and compliance, with a team of in-house sustainability experts who support every software engagement and implementation. Clients like Target, Georgia-Pacific, Intel, and Robinhood rely on Optera’s platform to build audit-ready GHG inventories across all three scopes, automate data capture, and meet California reporting deadlines with minimal lift and without relying on multiple disconnected tools.
Why Optera for SB 253 compliance? Best for companies that want enterprise software and expert guidance in one package, backed by two decades of consulting & GHG measurement experience. Their hands-on team helps ensure your first submission is transparent, accurate and auditable, which is critical in the 2026 transitional reporting cycle.
Optimized for: Mid-market, Enterprise (designed for companies over $1B in revenue)
Core strengths:
- Full access to an expert team included in the price of the software package (including technical implementation, data management, verification support and strategic advisory)
- Industry-leading accuracy and methodology documentation, with a 100% client success rate in third-party audits
- AI-powered reporting with a built-in knowledge base and flexibility to report to any framework or data request
- Supplier data integration, with robust supplier engagement and supplier KPI tracking tools
2. Watershed
Watershed is a leading enterprise sustainability platform designed to help companies measure, manage, and report their full carbon footprint with a strong focus on regulatory readiness. With 90+ Fortune 500 clients including Walmart, BlackRock, FedEx, and Visa, it brings both the scale and credibility required for audit-level disclosure.
Why Watershed for SB 253 compliance? Best for large enterprises that need comprehensive GHG data and a scalable, AI-forward platform with a proven track record of expertise in GHG measurement and reporting.
Optimized for: Mid-market, Enterprise (designed for companies over $1B in revenue)
Core strengths:
- Robust AI capabilities with agents that automate data cleaning and validation
- Strong industry reputation with 90+ Fortune 500 companies utilizing their platform
- Multi-framework reporting automation that pre-populates data across CDP, CSRD, ISSB, TCFD and more simultaneously
3. Persefoni
Persefoni’s platform includes a dedicated SB 253 compliance module, AI-powered anomaly detection for audit readiness, and established partnerships with major assurance firms like Deloitte and ERM. Its PCAF alignment also makes it the go-to for financial institutions tracking financed emissions.
Why Persefoni for SB 253 compliance? Best for companies in highly regulated industries — particularly financial services — that need airtight, audit-ready disclosures and established third-party assurance relationships already in place.
Optimized for: Mid-market, Enterprise (designed for companies over $1B in revenue)
Core strengths:
- GHG Protocol- and PCAF-aligned calculation engine with AI-powered data ingestion and anomaly detection
- Specific packages and pricing CA SB 253 & SB 261 compliance
- Investor-grade measurement and reporting of financed emissions, purpose-built for the financial services industry
4. Workiva
Workiva is primarily an ESG and financial reporting controls platform, with GHG calculation built in. Its XBRL tagging, role-based audit controls, and deep financial-ESG integration make it the strongest option for public companies that need SB 253 disclosures to connect seamlessly to SEC filings and financial reporting.
Why Workiva for SB 253 compliance? Best for publicly traded companies that need SB 253 data to live inside the same system as their financial disclosures, particularly those already using Workiva for CSRD or other GHG reporting.
Optimized for: Enterprise (designed for companies over $1B in revenue)
Core strengths:
- Seamless financial & ESG integration with in-platform XBRL tagging
- Collaboration tools to connect ESG, finance, compliance & legal teams
- Strong auditability features with approvals, tracking, and real-time co-authoring and version control
5. Greenly
With over 3,500 customers and more than 100 software integrations, Greenly offers one of the broadest integration ecosystems on this list, which significantly reduces manual data entry burden for small teams. Its AI-powered anomaly detection helps catch data errors, and it supports both California reporting alongside European frameworks like CSRD.
Why Greenly for SB 253 compliance? Best for mid-market companies without large in-house sustainability teams that need a user-friendly platform with wide integration support to stand up a compliant GHG inventory quickly.
Optimized for: SMB, Mid-market
Core strengths:
- Emphasis on streamlined, fast, cost-effective GHG measurement and compliance
- Robust global datasets and AI capabilities
- Customizable packaging and pricing with solutions tailored to industry, sustainability goals, and desired add-ons
6. Sweep
Sweep earned the top spot in the Verdantix 2026 Green Quadrant for Carbon Management Software. It is built for large, distributed organizations where SB 253 compliance requires coordinating emissions data across dozens of business units and suppliers. Its collaborative workflow tools and ESRS datapoint mapping give enterprises a single system for both California and global reporting obligations.
Why Sweep for SB 253 compliance? Best for large multinationals managing SB 253 alongside CSRD or CDP. Sweep’s cross-framework approach means one platform handles compliance across multiple regulatory regimes simultaneously.
Optimized for: Enterprise (designed for companies over $1B in revenue)
Core strengths:
- Built-in agentic AI to support multiple functions such as reporting and data analysis
- Regulatory support with multi-framework alignment, audit-ready traceability, and embedded guidance
- Integrated analytics on cost-savings and inefficiencies
7. Gravity Climate
Gravity Climate’s platform includes with market-leading ratings in AI data collection, abatement opportunity identification, and CO2 emissions forecasting. Built specifically for manufacturers and industrial supply chains, Gravity automates data ingestion from utilities, ERPs, and logistics systems, and the platform can be used to achieve compliance while identifying cost-saving energy projects.
Why Gravity Climate for SB 253 compliance? Best for manufacturers and industrial companies that need SB 253 compliance and a clear ROI story, as Gravity ties emissions reduction directly to energy cost savings and measurable business impact.
Optimized for: Mid-market, Enterprise (designed for companies over $1B in revenue)
Core strengths:
- GHG management and energy management in one system, delivering cost-saving options
- Designed for energy intensive supply chains like logistics & manufacturing
- Purpose-built toolset for investors to report emissions and drive energy efficiency
8. Novisto
Novisto has positioned itself as a financial-grade ESG system of record, and its 2026 acquisition of carbon specialist Minimum means it now combines enterprise-grade ESG controls with dedicated carbon accounting in a single platform. It offers automated data ingestion across business units, audit trails, approval workflows, and TCFD-aligned climate risk assessment that can support both SB 253 emissions reporting and SB 261 risk disclosure.
Why Novisto for SB 253 compliance? Best for large enterprises that want GHG accounting and broader ESG reporting in one integrated system, particularly those that have previously managed these workstreams in separate tools.
Optimized for: Enterprise (designed for companies over $1B in revenue)
Core strengths:
- Robust data collection capabilities including automated workflows and reminders
- Includes peer benchmarking, approval workflows and audit trails to meet financial-grade data standards
- ESG reporting automation with templates and metrics to map information to 25+ ESG taxonomies
9. Greenplaces
Greenplaces has a purpose-built toolset for both SB 253 and SB 261 compliance. It maintains a real-time CARB alert and deadline tracking system, offers expert-managed regulatory submissions, and has produced highly detailed CARB-specific compliance guidance, including a regularly updated FAQ library.
Why Greenplaces for SB 253 compliance? Best for mid-market companies that don’t have an internal sustainability team and need a vendor that will actively manage the CARB submission process on their behalf.
Optimized for: SMB, Mid-market
Core strengths:
- Platform scans global regulations and disclosure frameworks to flag relevant requirements
- Designed to streamline and simplify the carbon accounting & reporting process with one single platform
- Additional support backed by expert team
10. Good.Lab
Good.Lab bundles ESG software with hands-on expert support, making it well suited for mid-market companies and suppliers being asked to report emissions data by their customers. In 2025, they rolled out AI-enabled data extraction and spend classification to reduce the manual work of building a compliant Scope 1 and 2 inventory. It is developing its Climate Regulation Solution specifically for SB 253 and SB 261 readiness.
Why Good.Lab for SB 253 compliance? Best for suppliers and mid-sized companies navigating SB 253 for the first time, particularly those also responding to downstream customer data requests.
Optimized for: SMB, Mid-market
Core strengths:
- Integrated sustainability software & ESG consulting services for California compliance
- Platform incorporates robust Social & Governance reporting
- Flexible pricing model for various needs and use cases
