In 2025, sustainability reporting has entered a new era. The fragmented landscape of ESG disclosures is being replaced by a unified global framework led by the International Sustainability Standards Board […]

In 2025, sustainability reporting has entered a new era. The fragmented landscape of ESG disclosures is being replaced by a unified global framework led by the International Sustainability Standards Board (ISSB). With its newly adopted IFRS S1 and IFRS S2 standards, ISSB aims to provide companies and investors with a consistent, comparable, and transparent approach to sustainability reporting. 

As capital markets, regulators, and consumers increasingly demand robust Environmental, Social, and Governance (ESG) disclosures, companies face rising pressure to comply with these evolving ISSB reporting standards. Understanding the ISSB new standards, their latest changes, and global adoption trends is now a strategic necessity for businesses aiming to secure investor trust, regulatory compliance, and long-term resilience. 

What Are the ISSB Standards?

The ISSB was established by the IFRS Foundation to consolidate the various global ESG disclosure frameworks into one harmonized set of standards. Its two cornerstone standards, officially launched in 2023, form the backbone of sustainability reporting in 2025: 

• IFRS S1 – General Sustainability-related Disclosures:
  This sets out the overall framework for ESG reporting, covering general sustainability risks and opportunities that affect enterprise value across environmental, social, and governance dimensions. 

• IFRS S2 – Climate-related Disclosures:
  Building on the well-established TCFD framework, IFRS S2 focuses specifically on climate-related risks, governance, strategies, financial impacts, and scenario-based analysis. 

Both standards are principles-based, aiming to help organizations explain how sustainability factors influence financial performance, capital allocation, and long-term business viability. 

According to KPMG’s 2024 “The move to mandatory reporting” study, nearly 75% of G250 companies report climate risks aligned with TCFD—putting them in a strong position to transition smoothly to the mandatory ISSB requirements derived from TCFD’s architecture. [1]  

Latest Changes in ISSB Standards: What Has Evolved?

While the ISSB standards were launched in 2023, several important updates have been introduced in 2024 and early 2025 to strengthen their application and global consistency: 

1. Mandatory Full Scope 3 Emissions Disclosure

In 2025, IFRS S2 now mandates disclosure of Scope 1, 2, and full Scope 3 emissions across 15 subcategories (from upstream supply chain to product use and end-of-life). This aligns with evolving regulatory standards such as the EU CSRD and reflects growing market demand for value chain transparency. 

2. Mandatory Scenario-based Financial Impacts

Where climate scenario analysis was previously optional, companies are now required to report financial implications across multiple climate scenarios (e.g., 1.5°C vs. 4°C pathways). These scenarios must include quantified financial impacts on capital expenditure, insurance exposure, and asset valuations. This helps investors assess resilience under varying climate futures. 

3. Enhanced Board Oversight and Accountability

The latest ISSB governance disclosure requirements call for: 

• Explicit board-level climate risk oversight. 

• Integration of ESG metrics into executive remuneration. 

• Clear management structures assigning responsibility for climate strategy. 

This shift reflects a global push for boards to embed sustainability into core governance processes. 

4. Introduction of Limited Assurance Requirements

Starting in 2025, companies disclosing under ISSB must obtain at least limited assurance (third-party verification) on key disclosures, including Scope 1–3 emissions, climate targets, and governance structures. Full reasonable assurance is expected to become mandatory in several jurisdictions within 3 years. 

5. Emerging Focus Areas: Biodiversity, Human Capital & Supply Chain Resilience

While IFRS S1 and S2 focus on general and climate disclosures, ISSB has already announced its development of S3 and S4 standards addressing biodiversity, human capital, and supply chain dependencies. This expansion reflects growing investor expectations for holistic sustainability transparency beyond climate alone.

Global Adoption & Regulatory Alignment

Les global regulatory momentum behind ISSB standards is accelerating rapidly: 

This broad alignment underscores ISSB’s role as the de facto global baseline for ESG disclosures. According to the IFRS/ISSB 2024 “Progress on Corporate Climate‑related Disclosures” report, most asset managers and asset owners surveyed expect portfolio companies to shift from TCFD-aligned disclosures to the ISSB framework—citing clearer comparability and a reduction in greenwashing risks. [2]  

Practical ISSB Standards Summary for Reporting Teams

How Should Companies Prepare for ISSB Compliance? 

The Future of ISSB: What Comes Next?

Looking ahead, ISSB standards will continue evolving: 

• Expanded Sector Guidance: Industry-specific standards will be developed to address nuanced sustainability risks across sectors. 

• Digital Taxonomy Integration: ISSB disclosures will become machine-readable, easing automated investor analysis and regulatory oversight. 

• Global Assurance Convergence: International auditing bodies are developing unified assurance standards specifically tailored for ISSB compliance. 

The ISSB’s comprehensive roadmap aims to create one global ESG reporting language—bridging gaps between Europe’s CSRD, America’s SEC, and Asia-Pacific frameworks. 

Réflexions finales 

By 2025, ISSB reporting has moved from voluntary to vital. Companies that proactively adopt the ISSB new standards, embrace the latest changes in ISSB standards, and implement robust governance structures will: 

• Build investor confidence 

• Secure regulatory compliance 

• Enhance strategic resilience 

• Differentiate themselves as global sustainability leaders 

Start today by conducting an ISSB gap analysis. Engage your board. Upgrade your ESG data systems. And embed scenario-based financial planning into your enterprise strategy. Those who lead ISSB compliance will not only meet regulatory expectations but unlock real long-term value in a rapidly transforming global economy. 

Références : 

[1] https://assets.kpmg.com/content/dam/kpmg/sg/pdf/2024/11/the-move-to-mandatory-reporting-report.pdf  

[2] https://www.ifrs.org/content/dam/ifrs/supporting-implementation/issb-standards/progress-climate-related-disclosures-2024.pdf