GRI, IFRS S1 or ESRS? The Materiality and Audience Test That Should Drive Your Reporting Choice

The single most consequential question in sustainability reporting is not which framework has the longest disclosure list — it is which definition of materiality and which audience your organization is accountable to. GRI, IFRS S1 and the European Sustainability Reporting Standards (ESRS) were developed by different bodies, at different times, for different primary audiences, and they apply different materiality tests. For a board, that means the choice is a strategic decision driven by legal obligations, listing status and stakeholder base — not a ranking of comprehensiveness. This guide sets out the three materiality concepts, a strategic comparison, and the reporting pathways most organizations actually follow.

Navigating the Sustainability Reporting Landscape: A C-Suite Guide

Three systems dominate global sustainability disclosure. The GRI Standards are issued by the Global Reporting Initiative, an independent non-profit, as a modular set of Universal, Sector and Topic Standards; the revised Universal Standards took effect for reporting from 1 January 2023. IFRS S1 comes from the International Sustainability Standards Board (ISSB) under the IFRS Foundation, requiring disclosure of sustainability-related risks and opportunities across governance, strategy, risk management, and metrics and targets, effective for annual periods beginning on or after 1 January 2024. The ESRS were drafted by EFRAG and adopted by the European Commission under the Corporate Sustainability Reporting Directive (CSRD), applying to in-scope EU undertakings under Directive (EU) 2022/2464; they were adopted on 31 July 2023 and published in the Official Journal on 22 December 2023.

Reporting professionals caution against treating these as competing questionnaires. As the London Reporting Academy puts it, the three systems overlap in subject matter, but they begin with different reporting questions, apply different materiality tests and serve different accountability or decision-useful purposes. The practical task for a leadership team is therefore to match each framework to the decision it supports: capital allocation, regulatory compliance, or broad stakeholder accountability.

Understanding the Core: Materiality Concepts Defined

Financial materiality (IFRS S1). The ISSB standard focuses on sustainability-related risks and opportunities that could reasonably affect the entity's financial position over the short, medium or long term — its cash flows, access to finance or cost of capital. The scope is limited to financially material information, and the standard aims to inform enterprise value decisions for investors, lenders and other creditors.

Impact materiality (GRI). GRI's approach considers the organization's most significant impacts on the economy, environment and people. This scope is comprehensive for sustainability reporting: it captures supply-chain labor practices, community impact, biodiversity effects and other topics that matter to non-investor stakeholders even when they are not decision-useful for capital allocation.

Double materiality (ESRS). The EU regime applies both impact and financial materiality rather than a financial-materiality-only approach. EFRAG's own comparison document defines materiality under ESRS 1 as an entity-specific aspect of relevance based on the nature or magnitude, or both, of the sustainability matters to which the information relates, assessed in the context of the undertaking's sustainability reporting. In practice, an in-scope EU company must assess both outward impacts and financial effects, which widens the disclosure perimeter beyond either single lens.

Strategic Sustainability Reporting Framework Comparison

The table below categorizes each standard against the four dimensions that drive a board-level choice: who the report is for, what materiality test it applies, what it covers, and whether it carries legal force. Use it for a preliminary assessment of which framework aligns with your company's needs before testing specific obligations.

The mapping that emerges is straightforward: IFRS S1 prioritizes investors, GRI prioritizes broad stakeholder impacts, and ESRS combines both perspectives for EU-regulated undertakings. Note that GRI reporting does not substitute for compliance obligations under other standards — a company listed in an IFRS S1-adopting jurisdiction still has a compliance obligation for IFRS S1/S2 reporting regardless of any GRI report it publishes.

Strategic Reporting Pathways for Your Organization

Investor-focused compliance (IFRS S1-led). A company listed in a jurisdiction that has adopted the ISSB standards has a compliance obligation for IFRS S1/S2 reporting. Because the standard is designed to be interoperable with financial reporting, it is the natural backbone for organizations whose primary disclosure audience is the capital markets.

Multi-stakeholder engagement (GRI-led or supplemental). A company with a broad stakeholder base has a strong incentive to use the GRI Standards. Can a company use both GRI and IFRS S1? Yes — and, as Semtrio's analysis notes, many large companies do exactly this. IFRS S1/S2 satisfies regulatory and investor-facing requirements where adopted, while GRI provides the broader stakeholder narrative that a purely financially material disclosure set does not capture. Companies operating in IFRS-adopting jurisdictions frequently continue publishing a GRI-referenced report specifically to maintain that wider stakeholder relationship.

EU mandatory reporting (ESRS). Organizations within the CSRD's applicable scope report under the ESRS, with the double materiality assessment widening what must be disclosed. For multinationals, the practical consequence is that an EU-regulated subsidiary or listing can pull the group into ESRS-style reporting even where the parent follows ISSB-aligned standards elsewhere.

Making Your Strategic Choice: Key Considerations

Three questions should structure the board's decision. First, what does the law require? Legal applicability is jurisdiction- and scope-specific, and this article does not constitute legal advice on which standard is mandatory for a particular company. Second, who is the primary audience — capital providers, or a wider set of stakeholders including communities, workers and regulators? Third, what communication goals does the report serve? Because the frameworks were built for different audiences, they are complements rather than substitutes, and the real operational question is often how to satisfy multiple standards without tripling the workload.

The decision framework is therefore: start from legal obligations (ESRS if in EU scope; IFRS S1/S2 where your listing jurisdiction has adopted them), then layer GRI where stakeholder accountability demands impact disclosure that financial materiality alone will not surface. No single framework is "better" — each was designed for a different purpose, and treating them as substitutes is where reporting teams go wrong.

Your Strategic Reporting Decision: Aligning Frameworks with Goals

C-suite executives should select sustainability reporting frameworks based on their organization's legal obligations, primary stakeholder audience, and strategic communication goals, potentially combining frameworks to meet diverse needs. The evidence supports this: the standards differ systematically on materiality and audience, many large companies already run IFRS S1/S2 and GRI in parallel, and the ESRS double materiality test exists precisely because the EU legislature wanted both investor and impact perspectives in one statement.

The measurable indicator of a sound choice is this: the company's next sustainability report clearly articulates its chosen materiality approach and effectively addresses the information needs of its identified primary stakeholders, reflecting compliance where applicable. If the report does both — states its materiality lens explicitly and serves the audience the board identified — the framework decision has done its job; if it does not, revisit the mapping above before the next reporting cycle.

Sources

• Sustainability Reporting: GRI, IFRS S1 and ESRS — CASRAI
• GRI vs ESRS vs IFRS S1 and S2 — Reporting
• EFRAG
• GRI vs ISSB vs ESRS: Which Reporting Standard Applies? — Socious
• GRI vs IFRS S1/S2: Key Differences Explained — Semtrio