Linklaters has a series of Quick Guides that provide an overview of key sustainability disclosure regimes in the UK, EU and other jurisdictions. Click here to view all our Quick Guides.
This Quick Guide deals with the global sustainability disclosure standards developed by the International Sustainability Standards Board (“ISSB”) – IFRS S1 and IFRS S2.
Last updated on: 5 September 2025
ISSB standards – IFRS S1 and IFRS S2 | |
In a nutshell | The International Financial Reporting Standards (“IFRS”) Foundation created the ISSB in 2021 to develop a global baseline of sustainability disclosure standards that meets the information needs of investors. The IFRS Foundation is hoping to do for sustainability reporting what it has done for financial reporting with the IFRS Accounting Standards. In 2023, the ISSB published the final version of its first two global sustainability disclosure standards:
The ISSB’s intention is to provide a ‘building blocks’ model with a global baseline that countries can adapt or add to if they decide to implement the ISSB standards into their national regimes. The information required by the ISSB standards is designed to be provided alongside financial statements as part of the same reporting package. |
Mandatory or voluntary? | Voluntary – but a number of jurisdictions are in the process of incorporating the ISSB standards into local laws, making compliance with the ISSB standards (as adopted) mandatory (see below) |
Endorsement in other jurisdictions | More than 30 jurisdictions have implemented, or are in the process of implementing, the ISSB standards into their regulatory frameworks (see here). Some countries have adopted the ISSB standards with jurisdiction-specific modifications that are designed to help the standards work at a national level (see “Interoperability” below). |
Who does it apply to? | The ISSB standards can be used by corporates, financial institutions and others. An entity should make sustainability-related financial disclosures on the same basis as the related financial statements (e.g. if an entity prepares consolidated financial statements for a parent and its subsidiaries, the sustainability-related financial disclosures should also relate to the same group). |
When does it apply? | Companies were able to start using IFRS S1 and IFRS S2 on a voluntary basis for annual reporting periods beginning on or after 1 January 2024, with the first set of reports published in 2025. In the first year of reporting using the ISSB standards, companies are encouraged to prioritise reporting on climate-related risks and opportunities. In the second year, companies are expected to provide full reporting on other sustainability-related risks and opportunities in addition to climate issues. Entities should make disclosures at the same time as financial statements. |
What is required? | IFRS S1
IFRS S2
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Materiality | The ISSB standards are designed to meet the information needs of investors. The standards therefore have a financial materiality focus, meaning that reporting entities must disclose material information about any sustainability-related risks and opportunities that may affect the entity’s financial position in the short, medium and long term. Under the ISSB standards, information is "material" if omitting, misstating or obscuring it could reasonably be expected to influence decisions that investors, lenders and other creditors make on the basis of those reports. The EU’s Corporate Sustainability Disclosure Directive (“CSRD”) and European Sustainability Reporting Standards (“ESRS”), on the other hand, apply a double materiality standard. This requires in-scope companies to report on their impacts on people and the environment (impact materiality), as well as on how social and environmental issues affect them financially (financial materiality). |
Interaction with TCFD | The IFRS Foundation took over the monitoring of climate-related disclosures from the TCFD in 2024. The TCFD has since been disbanded. IFRS S2 incorporates, and builds on, the recommendations of the TCFD. Also, IFRS S1 uses the same four pillars as the TCFD in requiring entities to make disclosures about governance, strategy, risk management, metrics and targets in respect of wider sustainability issues. See “Interoperability” below. |
SASB standards | The ISSB assumed responsibility for the SASB standards in 2022. IFRS S1 requires preparers to refer to and consider the SASB standards in identifying sustainability-related risks and opportunities, if no relevant IFRS sustainability disclosure standard is available. See Quick Guide on SASB Standards. |
Transition plans | IFRS S2 requires an entity to disclose both retrospective and forward-looking information about its response to climate-related risks and opportunities, including plans to achieve any climate-related targets. It does not require a preparer to produce a transition plan if it does not yet have one or to publish a transition plan where it has one. What it requires is the disclosure of certain information about how the preparer is preparing to transition. In June 2025, the ISSB published guidance on disclosures about transition plans (see here). The guidance is intended to support entities in applying IFRS S2. The ISSB guidance builds on the materials developed by the Transition Plan Taskforce (“TPT”). The IFRS Foundation took over responsibility for the TPT's disclosure-specific materials in 2024. |
Interoperability | As noted above, the ISSB’s intention is to provide a global baseline that countries can adapt or add to if they decide to when implementing the ISSB standards. To date, jurisdictions have taken a variety of approaches and some stakeholders have expressed concerns that the changes made by certain jurisdictions may be too extensive, making reporting across various jurisdictions difficult. This is a particular concern for investors and companies that have significant cross-border operations and must comply with more than one set of jurisdictional requirements. Significant changes to the standards at national level could lead to regulatory fragmentation and divergence, ultimately reducing some of the benefits that the ISSB standards set out to achieve. For further information in relation to interoperability between the ISSB standards and the: |
Next steps | The ISSB has indicated that its key focus areas are:
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Key documents |
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Linklaters materials |
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