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Sustainability reporting is the practice of an organisation publicly disclosing information about its environmental, social and governance-related risks, opportunities and impacts, usually in a recurring report that follows a named framework or legal standard. If you need to know which framework applies, what a report must contain and where the rules stand in the EU, this page covers each in turn.
What is sustainability reporting?
Sustainability reporting is the disclosure of sustainability-related information by an organisation, either to investors and lenders or to a wider group of stakeholders. The IFRS Foundation states the objective of its general standard, IFRS S1, as requiring an entity to disclose information about its sustainability-related risks and opportunities that is useful to users of general purpose financial reports. The GRI Standards take a wider audience view and are organised around an organisation’s impacts. Which of these purposes a report serves determines its content, so the first question for any report is the audience.
It helps to separate the report (the published document) from the reporting process (collecting data, setting boundaries, assurance and internal controls). Most of the practical work sits in the process, and research organisations that need emissions inputs will find the method pages GHG Protocol and Scope 1, 2 and 3 emissions useful.
Sustainability reporting frameworks: GRI, ISSB (IFRS S1) and ESRS
Three families of standards dominate current practice. They overlap but are not interchangeable.
| Framework | Issuer | What it asks for | Status stated on the issuer’s page |
|---|---|---|---|
| GRI Standards | Global Reporting Initiative | Modular set: Universal Standards (GRI 1, 2, 3), Sector Standards and Topic Standards | Revised Universal Standards published October 2021, effective for reporting from 1 January 2023 |
| IFRS S1 General Requirements | ISSB / IFRS Foundation | Disclosure of sustainability-related risks and opportunities, structured in four content areas: governance, strategy, risk management, metrics and targets | Effective for annual periods beginning on or after 1 January 2024; earlier application permitted if IFRS S2 is also applied |
| European Sustainability Reporting Standards (ESRS) | Drafted by EFRAG; adopted by the European Commission under the CSRD | Reporting by in-scope EU undertakings under Directive (EU) 2022/2464 | ESRS adopted 31 July 2023; published in the Official Journal 22 December 2023 |
Sources: IFRS S1 page (ifrs.org), GRI Standards page (globalreporting.org), European Commission corporate sustainability reporting page, all read 8 November 2026.
What does a sustainability report contain?
Contents are set by the framework used, not by a single universal template. Under IFRS S1 a report is organised around four content areas: governance (who oversees sustainability-related risks and opportunities), strategy, risk management and metrics and targets. Under GRI, a report draws on the Universal Standards for general and material-topic disclosures and on Sector and Topic Standards for specific subjects. Under the CSRD, companies report the sustainability risks and opportunities they face and their impacts on people and the environment.
Worked example: an emissions-intensity metric
Metrics and targets sections often pair an absolute figure with a ratio so readers can compare organisations of different size. The numbers below are illustrative, not drawn from any real organisation.
- Reported Scope 1 and 2 emissions: 12,000 tonnes CO2e
- Annual revenue: 480 million (currency units)
- Intensity = 12,000 / 480 = 25 tonnes CO2e per million of revenue
If the next year’s emissions fall to 11,400 tonnes while revenue rises to 500 million, intensity is 11,400 / 500 = 22.8, a fall of 2.2 tonnes per million, or 8.8 percent (2.2 / 25). Absolute emissions fell by 600 tonnes, or 5.0 percent. The two measures can diverge, which is why a report should state which it uses and what boundary it applies.
Formula with symbols explained
The intensity ratio used in the worked example is a simple quotient. It is a convention for comparing organisations of different size, not a metric defined by GRI, IFRS S1 or the ESRS, so a report should state its formula and boundary.
I = E / D
- I: emissions intensity, in tonnes CO2e per unit of the denominator (for example per million of revenue).
- E: reported emissions for the stated boundary and period, in tonnes CO2e (for example Scope 1 and 2 combined).
- D: the denominator chosen for the report, such as revenue in millions, full-time employees or units produced. It must be the same measure in every period compared.
Year-on-year change is (It – It-1) / It-1, where t is the current reporting period and t-1 the prior one. In the example: (22.8 – 25) / 25 = -8.8 percent.
Interpretation: how to read intensity and absolute figures
| Pattern | What it shows | What it does not show |
|---|---|---|
| Intensity falls, absolute emissions fall | Emissions fell and did so by more than the denominator, if the denominator grew | Whether the fall came from operations or from a boundary change |
| Intensity falls, absolute emissions rise | The denominator grew faster than emissions | Any reduction in total emissions |
| Intensity rises, absolute emissions fall | The denominator fell by more than emissions | Worse performance in absolute terms |
| Intensity flat, absolute emissions rise | Emissions grew in step with the denominator | Efficiency gains |
Read intensity and absolute figures together, and check that boundary, period and denominator are unchanged before drawing a conclusion.
How to report it
State the figure, the formula, the boundary, the denominator and the framework the disclosure follows. A report line might read: Scope 1 and 2 emissions intensity was 22.8 tonnes CO2e per million of revenue in the reporting year (prior year: 25.0), calculated as Scope 1 and 2 emissions divided by annual revenue; boundary and emission factors are described in the methodology note. The figures here repeat the illustrative example above and do not describe a real organisation.
If you cite a standard in a document, give the issuer, title and access date, as in the Sources list below, for example: IFRS Foundation. IFRS S1 General Requirements for Disclosure of Sustainability-related Financial Information. ifrs.org (accessed 8 November 2026).
Calculating intensity in Excel, R and Python
Using the illustrative figures from the worked example:
# Excel: emissions in B2, revenue (millions) in C2
=B2/C2
# R
emissions <- c(12000, 11400); revenue <- c(480, 500)
intensity <- emissions / revenue # 25.0 22.8
(intensity[2] - intensity[1]) / intensity[1] # -0.088
# Python
emissions = [12000, 11400]; revenue = [480, 500]
intensity = [e / r for e, r in zip(emissions, revenue)] # [25.0, 22.8]
change = (intensity[1] - intensity[0]) / intensity[0] # -0.088EU CSRD timeline, 2022 to 2026
The European Commission's page lists these steps (read 8 November 2026):
- 14 December 2022: Directive (EU) 2022/2464 (CSRD) published in the Official Journal.
- 31 July 2023: Commission adopts the ESRS; published 22 December 2023.
- 26 February 2025: Commission omnibus simplification proposal.
- 14 April 2025: stop-the-clock measure.
- 11 July 2025: delegated act with quick fixes to the ESRS.
- 30 July 2025: Commission recommendation on a voluntary standard (VSME).
- 9 December 2025: political agreement on Omnibus I.
- 3 July 2026: Commission adopts delegated acts simplifying the ESRS and setting voluntary standards for undertakings covered by the value-chain cap.
Scope thresholds have changed during this process. Check the current text of the Directive on EUR-Lex for whether a given organisation is covered, rather than relying on a summary.
Sustainability reporting vs ESG reporting
The terms are used interchangeably in practice, and no single issuer defines the difference. The standards above use the language of sustainability-related risks, opportunities and impacts. ESG (environmental, social, governance) is more common in investor and ratings contexts. When choosing wording for your own documents, follow the vocabulary of the framework you report against.
Common mistakes
- Mixing frameworks without saying so. A report should name which standard each disclosure follows.
- Comparing intensity figures built on different boundaries or denominators.
- Treating a voluntary report as meeting a legal requirement. The CSRD applies as law to in-scope undertakings; voluntary standards do not.
- Relying on outdated effective dates. The EU dates above have moved more than once.
Frequently asked questions
What is the difference between sustainability reporting and financial reporting?
IFRS S1 is designed to sit alongside financial statements: it asks for sustainability-related information that is useful to users of general purpose financial reports.
Which framework should an organisation use?
It depends on legal obligations and audience. EU in-scope companies report under the ESRS; many others choose GRI for impact reporting or IFRS S1 for investor-focused reporting.
Does sustainability reporting apply to research institutions?
Only where law or a funder requires it, or the institution chooses to report. Related method pages cover carbon accounting in research, the research carbon footprint, sustainable procurement and laboratory sustainability.
Sources
- IFRS Foundation, IFRS S1 General Requirements for Disclosure of Sustainability-related Financial Information, ifrs.org/issued-standards/ifrs-sustainability-standards-navigator/ifrs-s1-general-requirements/ (read 8 November 2026).
- Global Reporting Initiative, GRI Standards, globalreporting.org/standards/ (read 8 November 2026).
- European Commission, Corporate sustainability reporting, finance.ec.europa.eu (company reporting section), (read 8 November 2026).
