Regional spotlight: Corporate climate disclosures in US — what's different and why it matters

Corporate climate disclosure in the United States has entered a period of unprecedented complexity. While the European Union has moved decisively toward mandatory, standardized sustainability reporting through the CSRD, and the ISSB has established global baseline standards, the US regulatory landscape remains fractured across federal and state jurisdictions, shaped by political headwinds, litigation challenges, and a distinctly American tension between investor protection mandates and anti-regulatory sentiment. For executives navigating this environment, the operational reality of US climate disclosure differs substantially from the global narrative of inevitable convergence toward universal standards.

Why It Matters

The US represents the world's largest capital market, with over $46 trillion in domestic equity market capitalization and approximately 5,800 public companies filing with the Securities and Exchange Commission (SEC). How these companies measure, report, and disclose climate-related risks and emissions has profound implications for global capital allocation, supply chain decarbonization, and the credibility of corporate net-zero commitments.

The SEC's final climate disclosure rules, adopted in March 2024, were immediately challenged in federal court and subsequently stayed pending judicial review. This legal uncertainty has created a disclosure environment unlike any other major jurisdiction: companies face the simultaneous possibility of comprehensive mandatory requirements becoming effective and those same requirements being struck down or substantially weakened. The Eighth Circuit Court of Appeals consolidated multiple challenges and heard oral arguments in September 2024, with a ruling expected in 2026 that will determine the scope and enforceability of federal climate disclosure mandates.

Meanwhile, California has moved forward with its own ambitious disclosure laws. SB 253 (the Climate Corporate Data Accountability Act) requires companies with annual revenues exceeding $1 billion that do business in California to report Scope 1, 2, and 3 greenhouse gas emissions. SB 261 (the Climate-Related Financial Risk Act) mandates that companies with revenues over $500 million publish biennial climate-related financial risk reports aligned with TCFD recommendations. These laws apply regardless of whether a company is publicly traded, extending disclosure requirements to large private companies for the first time in the US. The California Air Resources Board (CARB) is developing implementing regulations, with initial Scope 1 and 2 reporting expected to begin in 2026 and Scope 3 reporting in 2027.

The financial consequences of mismanaging disclosure obligations are substantial. The SEC's Division of Enforcement has increased climate and ESG-related enforcement actions, with $750 million in penalties assessed across 14 cases in fiscal year 2025, including greenwashing charges against several prominent asset managers and misleading emissions claims by public companies. State attorneys general in both progressive and conservative states have pursued separate enforcement agendas: New York and Massachusetts targeting fossil fuel companies for alleged climate risk misrepresentation, while Texas and West Virginia have challenged what they characterize as politicized ESG investing practices.

Key Concepts

SEC Climate Disclosure Rules require registrants to disclose material climate-related risks, describe governance and risk management processes, provide Scope 1 and Scope 2 emissions data (for large accelerated and accelerated filers), and disclose the financial impacts of severe weather events and transition activities exceeding 1% of relevant financial statement line items. The rules notably excluded mandatory Scope 3 emissions reporting from the final version, a significant departure from the proposed rule and from the EU's CSRD requirements. The compliance timeline, if the rules survive legal challenge, requires large accelerated filers to begin reporting for fiscal years beginning in 2025, with smaller filers phased in through 2028.

California SB 253 and SB 261 create the nation's most expansive state-level climate disclosure mandates. SB 253 covers approximately 5,300 companies and requires third-party verified emissions reporting across all three scopes. SB 261 applies to roughly 10,000 entities and requires TCFD-aligned risk disclosures. Both laws apply based on revenue thresholds and California business activity, capturing many companies that are not SEC registrants. Implementation timelines were adjusted in 2025 through SB 219, which delayed initial reporting deadlines by two years and gave CARB additional rulemaking authority.

TCFD Framework (Task Force on Climate-Related Financial Disclosures) has become the de facto organizing structure for voluntary US climate disclosures, with over 4,000 global supporters including most S&P 500 companies. While the TCFD itself was dissolved in 2023 with its monitoring responsibilities transferred to the IFRS Foundation, its four-pillar framework (Governance, Strategy, Risk Management, Metrics and Targets) remains embedded in SEC rules, California legislation, and voluntary reporting frameworks.

Double Materiality vs. Financial Materiality represents a fundamental philosophical difference between US and EU approaches. The SEC rules adopt a financial materiality standard: companies disclose climate information only to the extent it is material to investment decisions. The EU's CSRD requires double materiality: companies must disclose both how climate change affects the company (financial materiality) and how the company affects the climate (impact materiality). This distinction means that a US company may legally omit climate impact information that would be mandatory under European rules, even when reporting on the same operations.

Scope 3 Reporting covers indirect emissions across a company's entire value chain, including purchased goods, transportation, employee commuting, and use of sold products. Scope 3 typically represents 70-90% of a company's total carbon footprint but is also the most difficult to measure accurately. The SEC excluded mandatory Scope 3 from its final rules, while California requires it under SB 253 with a safe harbor provision protecting companies from liability for good-faith Scope 3 estimates. The EU's CSRD mandates Scope 3 disclosure under the European Sustainability Reporting Standards (ESRS).

What's Working

Voluntary Leadership by Large Corporations

Despite regulatory uncertainty, many large US companies have built sophisticated disclosure programs that exceed current mandatory requirements. Microsoft publishes an annual Environmental Sustainability Report covering all three emission scopes with detailed methodology documentation and third-party verification. The company disclosed $31 billion in sustainability-linked capital commitments through 2030 and reports progress against its 2030 carbon negative target using a framework that integrates financial and environmental metrics. Salesforce has similarly invested in comprehensive climate disclosure, including real-time carbon accounting integrated into its enterprise resource planning systems.

A 2025 analysis by the Governance and Accountability Institute found that 98% of S&P 500 companies published some form of sustainability report, up from 20% in 2011. Among these, 78% reported Scope 1 and 2 emissions, 62% reported at least partial Scope 3 data, and 45% obtained third-party assurance over their emissions data. This voluntary adoption has created a baseline of corporate capacity that will facilitate compliance when mandatory requirements take effect.

California as a Regulatory Catalyst

California's disclosure laws have had a catalytic effect on corporate preparedness far beyond the state's borders. Because the laws apply to any company doing business in California above revenue thresholds, including companies headquartered in other states and countries, they have prompted thousands of firms to accelerate their measurement and reporting capabilities. Deloitte's 2025 survey of 800 US companies found that 67% had begun building compliance infrastructure for SB 253 and SB 261, even before final implementing regulations were published. Many companies report that preparing for California requirements simultaneously positions them for SEC compliance, creating a regulatory efficiency that partially offsets the burden of multiple overlapping mandates.

Carbon Accounting Technology Ecosystem

The US has developed the most mature commercial ecosystem for climate disclosure technology. Companies including Persefoni, Watershed, Sinai Technologies, and Sweep have raised over $1.5 billion in venture capital to build carbon accounting platforms that automate emissions measurement, manage disclosure workflows, and facilitate assurance processes. Persefoni, valued at $850 million after its 2024 Series C, serves over 200 enterprise clients and offers automated alignment with SEC, CSRD, and California reporting requirements from a single data platform. Watershed, backed by Sequoia Capital, has developed supply chain emissions modeling tools that address the Scope 3 measurement challenge by combining spend-based estimates with supplier-specific activity data.

What's Not Working

Regulatory Fragmentation and Legal Uncertainty

The most significant barrier to effective climate disclosure in the US is the absence of a settled, nationally uniform standard. Companies face overlapping and potentially conflicting requirements from the SEC (pending litigation), California (implementing regulations still in development), the EU's CSRD (for companies with significant European operations), and various voluntary frameworks. A 2025 survey by PwC found that large multinational companies were tracking an average of 4.7 distinct disclosure frameworks, with compliance costs averaging $2.3 million annually for companies in the $5-50 billion revenue range. The uncertainty about which requirements will ultimately apply, and in what form, makes it difficult for companies to optimize their compliance investments.

Political Polarization of ESG Disclosure

Climate disclosure in the US has become entangled in broader political disputes over ESG investing and corporate governance. Twenty-three states have introduced or enacted anti-ESG legislation restricting state pension fund investments in companies or asset managers that incorporate climate considerations into investment decisions. Texas's 2021 law banning state contracts with financial institutions that "boycott" fossil fuels led several major asset managers to modify or downplay their climate-related activities. This politicization creates a challenging environment for corporate executives, who face pressure from progressive shareholders and regulators to disclose more climate information while simultaneously facing backlash from conservative policymakers and constituents for the same disclosures.

Scope 3 Data Quality and Liability Concerns

Even where companies attempt comprehensive Scope 3 reporting, data quality remains a fundamental challenge. The GHG Protocol's Scope 3 standard identifies 15 categories of indirect emissions, many of which require estimates based on industry averages, economic input-output models, or supplier-provided data of variable reliability. The EPA's Supply Chain Greenhouse Gas Emission Factors database, updated in 2024, provides spend-based emission factors, but these averages can differ from actual supplier emissions by 40-200%. Companies worry that reporting inaccurate Scope 3 data could expose them to securities fraud liability or state attorney general enforcement, creating a chilling effect that discourages disclosure. California's safe harbor provision for good-faith Scope 3 reporting addresses this concern partially, but no equivalent protection exists under federal securities law.

US vs. Global Comparison

Factor	US	EU (CSRD)	ISSB (Global Baseline)
Materiality Standard	Financial materiality	Double materiality	Financial materiality
Scope 3 Mandatory	No (SEC); Yes (California)	Yes	Yes (phased)
Applicability	Public companies (SEC); revenue-based (CA)	~50,000 companies (EU + non-EU with EU ops)	Voluntary, jurisdiction-dependent
Assurance Requirement	Limited (phased to reasonable)	Limited progressing to reasonable	Jurisdiction-dependent
Private Company Coverage	Yes (California only)	Yes (large private companies)	No direct mandate
Enforcement	SEC, state AGs	National regulators	N/A (national adoption)
Political Risk	High (anti-ESG backlash)	Low (broad political consensus)	Moderate
Current Status	Litigation stay (SEC); rulemaking (CA)	Effective, reporting begins 2025	Adopted by 20+ jurisdictions

Action Checklist

• Conduct a jurisdictional mapping exercise to identify all applicable disclosure requirements (SEC, California, CSRD, voluntary frameworks)
• Establish a cross-functional disclosure steering committee including legal, finance, sustainability, and investor relations
• Invest in Scope 1 and 2 emissions measurement infrastructure with third-party verification capability, as this is required under all frameworks
• Begin Scope 3 estimation using hybrid methodologies (spend-based plus supplier-specific) to build organizational capacity regardless of regulatory outcomes
• Engage external legal counsel to assess litigation risk and develop disclosure language that satisfies multiple regulatory frameworks simultaneously
• Evaluate carbon accounting technology platforms that support multi-framework reporting from a single data architecture
• Develop board-level climate governance structures, as all major frameworks require disclosure of governance oversight processes
• Monitor the Eighth Circuit ruling on SEC climate rules and CARB rulemaking for California laws to adjust compliance timelines accordingly

FAQ

Q: Should US companies wait for regulatory clarity before investing in climate disclosure capabilities? A: No. Regardless of the outcome of SEC litigation, companies doing business in California will face mandatory emissions reporting under SB 253 and SB 261. Companies with European operations face CSRD requirements. And investor expectations for climate disclosure continue to intensify: BlackRock, State Street, and Vanguard, which collectively manage over $23 trillion in assets, all require or strongly encourage portfolio companies to report climate data. Building measurement and reporting infrastructure now is a risk management investment, not a speculative compliance bet.

Q: How do US disclosure requirements compare to the EU's CSRD in practical terms? A: The SEC rules are narrower in scope. They focus on financially material climate risks and Scope 1/2 emissions for larger filers, without requiring Scope 3 or impact materiality disclosures. The CSRD covers a much broader range of sustainability topics (including biodiversity, labor practices, and governance) and requires double materiality assessment. For US companies subject to both frameworks, the CSRD will generally be the binding constraint, and SEC compliance becomes a subset of CSRD compliance rather than an additional burden.

Q: What is the estimated cost of comprehensive climate disclosure compliance for a mid-cap US company? A: For a company with $2-10 billion in revenue and operations in the US and EU, expect annual compliance costs of $1.5-4 million covering: carbon accounting platform licensing ($200-500K), third-party assurance ($150-400K), internal headcount (2-5 FTEs at $150-250K loaded cost each), legal advisory ($100-300K), and data collection from supply chain partners ($100-500K). First-year implementation costs are typically 2-3x annual run-rate costs due to system setup, baseline development, and process design. These costs should be evaluated against the potential benefits: reduced cost of capital (studies indicate 20-40 basis point improvement for strong disclosers), improved ESG ratings, and avoided enforcement risk.

Q: How should companies handle the tension between disclosure expectations and anti-ESG political pressure? A: Focus disclosure language on financial risk and fiduciary duty rather than environmental advocacy. Frame climate reporting as material risk management, which it is under SEC doctrine, rather than as a values-based commitment. This framing is legally defensible across political environments and aligns with the financial materiality standard adopted by both the SEC and ISSB. Companies operating in anti-ESG jurisdictions should ensure that their sustainability programs are structured around shareholder value creation and risk mitigation, which are objectives that transcend political positioning.

Q: What role does third-party assurance play in US climate disclosure credibility? A: Assurance is rapidly moving from optional to expected. The SEC rules require limited assurance over Scope 1 and 2 emissions, progressing to reasonable assurance over time. California SB 253 requires third-party verification of all reported emissions. Among S&P 500 companies voluntarily reporting emissions, 45% obtained some form of third-party assurance in 2025, up from 29% in 2023. Investors increasingly discount unassured emissions data, and the Big Four accounting firms (Deloitte, EY, KPMG, PwC) have all established dedicated sustainability assurance practices. Companies should engage assurance providers early, as demand currently exceeds supply and lead times for initial engagements average 4-6 months.

Sources

• Securities and Exchange Commission. (2024). The Enhancement and Standardization of Climate-Related Disclosures for Investors: Final Rule. Washington, DC: SEC.
• California Legislature. (2023). SB 253: Climate Corporate Data Accountability Act and SB 261: Climate-Related Financial Risk Act. Sacramento, CA.
• Governance and Accountability Institute. (2025). Sustainability Reporting in Focus: S&P 500 and Russell 1000 Analysis. New York: G&A Institute.
• PricewaterhouseCoopers. (2025). Global Climate Disclosure Readiness Survey: US Market Analysis. New York: PwC.
• Deloitte. (2025). Preparing for California Climate Disclosure Laws: Corporate Readiness Assessment. San Francisco: Deloitte.
• BlackRock Investment Stewardship. (2025). 2025 Engagement Priorities: Climate Risk and Transition Planning. New York: BlackRock.
• European Financial Reporting Advisory Group (EFRAG). (2024). ESRS Implementation Guidance for Non-EU Companies. Brussels: EFRAG.
• US Environmental Protection Agency. (2024). Supply Chain Greenhouse Gas Emission Factors for US Industries and Commodities. Washington, DC: EPA.