IFRS S1 and S2 (ISSB)

ISSB is a baseline, not itself a law — but a growing number of jurisdictions are adopting IFRS S1/S2 (or local equivalents) as mandatory.

Australia has introduced AASB S1 and S2, with phased application starting from 2025 for the largest companies. The United Kingdom is developing UK Sustainability Reporting Standards based on ISSB. Hong Kong, Singapore, and Japan have all moved toward ISSB-aligned mandatory regimes. Brazil, Nigeria, Türkiye, Ghana, and Uganda have published jurisdictional roadmaps for adoption. The IFRS Foundation maintains a public adoption tracker showing the growing list.

In jurisdictions where IFRS S1/S2 hasn’t been adopted yet, the standards are increasingly used voluntarily by companies preparing for future mandatory regimes, by listed companies meeting investor expectations, and by companies in the value chains of larger regulated entities.

For a mid-sized company outside an ISSB-adopting jurisdiction, the most common driver is investor pressure or anticipated future regulation. Listed companies and companies preparing for IPO often adopt IFRS S1/S2 voluntarily because their investors expect it. Private companies sometimes adopt the climate-specific S2 alongside GHG Protocol reporting because their banks or large customers ask for ISSB-aligned data.

GreenSphere supports IFRS S1 and S2 reporting end-to-end, with particular depth on the climate disclosures in S2.

• Four core content areas structured into the platform: governance, strategy, risk management, and metrics & targets. You log narrative content alongside quantitative data, all linked to the underlying sources.
• GHG emissions across Scopes 1, 2, and 3 — calculated using GHG Protocol methodologies, which is what S2 expects. Full data provenance on every emission factor.
• Industry-based metrics drawn from the SASB Standards now embedded in S2, mapped to your sector.
• Climate-related financial metrics — capital expenditure aligned to climate-related risks and opportunities, internal carbon prices, and the financial effects of climate-related risks.
• Targets and progress tracking — base years, milestones, and trajectories against any climate targets you set.
• Statement of compliance support — the audit trail and disclosure structure are designed to support an explicit statement of compliance when you’re ready to make one.

If you’re new to IFRS S1/S2, start with S2. The climate disclosures are where most early reporters focus, and they’re the part that most directly maps to the GHG Protocol emissions data you may already be collecting. GreenSphere’s data layer covers the quantitative side of S2 from day one — emissions, financial metrics, targets — and the narrative sections (governance, strategy, risk management) are structured to walk you through what’s required.

If you’ve reported under TCFD before, the transition to IFRS S2 is largely a matter of expanding the scope and adding industry-based SASB metrics. The four core content areas are the same.

If you’re switching from spreadsheets, the immediate benefit is that quantitative disclosures stop being a manual exercise. Your emissions data, your financial metrics, your target trajectories — all calculated automatically from the underlying activity data, all traceable to the source.