ISSB Reporting Software for IFRS S1 and IFRS S2

ISSB reporting software collects the data behind IFRS S1 and IFRS S2, keeps the evidence attached to it, and produces a disclosure a reviewer can follow back to source. Horizon ESG reports IFRS S1 and S2 from the same dataset that produces CSRD, ESRS, GRI and TCFD disclosures, so one set of numbers serves every framework you have to file.

What IFRS S1 and IFRS S2 ask for

The two standards are deliberately close in shape to TCFD, which is why the transition is a change of wording more than a change of work. Both are built on the same four pillars: governance, strategy, risk management, and metrics and targets.

• IFRS S1 covers sustainability-related risks and opportunities that could reasonably affect an entity’s prospects, reported over the same period and with the same timing as the financial statements.
• IFRS S2 covers climate specifically: physical and transition risk, scenario analysis, Scope 1, 2 and 3 greenhouse gas emissions, and the targets set against them.
• Connectivity is the part most teams underestimate. The disclosures have to reconcile with the financial statements and be published alongside them, which puts sustainability data on a financial reporting timetable.

Where ISSB reporting is being adopted

The ISSB standards are not adopted by a single global rule. Each jurisdiction decides, so a group with entities in several countries can face different start dates for the same disclosure.

• United Kingdom: UK Sustainability Reporting Standards are based on IFRS S1 and S2, with the FCA planning rules for listed companies. Horizon covers the transition in detail on our UK SRS reporting page.
• Existing TCFD reporters: the TCFD’s monitoring role passed to the ISSB in 2023, so climate disclosure continues under IFRS S2 rather than stopping. Our TCFD reporting software page explains what carries over.
• Groups also reporting under CSRD: the ESRS and the ISSB standards overlap heavily on climate. Reporting both from one dataset is the difference between one exercise and two.

What ISSB reporting software has to do

1. Collect once, report many times. The same emissions figure has to serve IFRS S2, ESRS E1 and any voluntary framework, without being recalculated in a spreadsheet each time.
2. Hold the evidence. Every number needs its source document, its owner and its timestamp, because an assurance provider will ask for all three.
3. Support scenario analysis. IFRS S2 expects climate resilience to be assessed against scenarios, and the assumptions behind that assessment to be disclosed.
4. Handle Scope 3. Category by category, with the estimation method recorded, since this is where most of the footprint and most of the uncertainty sits.
5. Keep to the financial timetable. Same reporting period, same publication date, which means the data has to be ready when the accounts are.

How Horizon ESG handles IFRS S1 and S2

One platform, one dataset, and an audit trail that travels with the figures.

• Framework mapping. A data point entered once maps to IFRS S1 and S2, ESRS, GRI and TCFD, so adding a framework does not add a collection exercise.
• Evidence trail. Each figure carries its source, who entered it and when it changed, which is what an assurance engagement runs on.
• Carbon accounting built in. Scope 1, 2 and 3 with the calculation method visible rather than buried in a formula.
• Gap analysis. See which IFRS S1 and S2 disclosures you can already support and which have no data behind them yet, before the deadline decides for you.
• Assurance-ready output. Built for the reviewer as well as the reader, which matters as assurance requirements tighten under ISSA 5000.

Frequently asked questions

What is ISSB reporting software?

Software that collects sustainability and climate data, keeps the supporting evidence attached to each figure, and produces disclosures aligned to IFRS S1 and IFRS S2 that an assurance provider can trace back to source.

Does ISSB replace TCFD?

In effect, yes. The ISSB took over monitoring of TCFD-aligned disclosure in 2023, and IFRS S2 carries the same four pillars forward. Work already done for TCFD is reusable rather than wasted.

Do I need separate software for ISSB and CSRD?

No, and using two is how teams end up with two versions of the same number. Horizon reports IFRS S1 and S2 alongside ESRS from one dataset.

When do the ISSB standards apply to my company?

It depends on where you are listed or incorporated, because adoption is jurisdiction by jurisdiction. UK-listed companies should plan around UK SRS, which is based on IFRS S1 and S2.

How much does ISSB reporting software cost?

Horizon starts at £20 per user per month on Pro and £15 per user per month on Business for teams of five or more, with a free two-month trial. Full detail is on our pricing page.

Book a 15-minute demo and we will show IFRS S1 and S2 reporting against your own frameworks, or start the free two-month trial.