ProcessSustainability
Running a double materiality assessment that stands up to assurance
A double materiality assessment decides which sustainability matters a company reports on under ESRS by testing each one twice: for its impact on people and the environment, and for its financial effect on the company. Done well, it is a documented sequence of judgements with evidence, thresholds and owners, not a survey-driven matrix, and the record of how it was done is itself subject to assurance.
On this page
- Who needs this assessment after the Omnibus changes
- The assessment as a pipeline from context to disclosure
- Six steps, each with a record an assurer can follow
- Impact materiality and financial materiality side by side
- Documentation to keep for limited assurance
- A hypothetical food manufacturer separates the two tests
- Questions and answers
- Sources
Who needs this assessment after the Omnibus changes
The assessment as a pipeline from context to disclosure
- Business and value chain
Activities, business relationships, geographies and the people and ecosystems each one touches.
- Long list of IROs
Candidate impacts, risks and opportunities, built from the ESRS sustainability matters and your own evidence.
- Impact scoring
Severity and, for potential impacts, likelihood, judged with input from affected stakeholders.
- Financial scoring
Likelihood and magnitude of effects on cash flows, financing and cost of capital.
- Thresholds and validation
Pre-agreed cut-offs applied, results consolidated and challenged by management.
- Disclosure mapping
Each material matter linked to ESRS disclosure requirements and a named data owner.
Six steps, each with a record an assurer can follow
Map the business model, value chain and affected stakeholders
Describe own operations and the upstream and downstream value chain by activity and geography, and list who is affected at each point: workers in the value chain, communities, consumers, and nature as a silent stakeholder. EFRAG's IG 1 distinguishes affected stakeholders from users of the sustainability statement, and both groups matter here3.
Build the long list of impacts, risks and opportunities
Start from the list of sustainability matters in ESRS 1 Appendix A2 and add company-specific ones from incident logs, grievance data, supplier audits, sector guidance and existing risk registers. Phrase each item as a specific impact, risk or opportunity, not a topic name.
Assess impact materiality
For actual negative impacts, judge severity from scale, scope and irremediable character; for potential impacts, combine severity with likelihood. For potential negative human rights impacts, severity takes precedence over likelihood2. Positive impacts are judged on scale, scope and, if potential, likelihood.
Assess financial materiality
Ask whether each matter triggers, or could reasonably be expected to trigger, material effects on development, financial position, performance, cash flows, access to finance or cost of capital, judged by likelihood and magnitude2. Use the enterprise risk register's scales where possible so the two processes agree.
Set thresholds, consolidate and validate
Agree thresholds before scoring, apply them, merge duplicates across business units, and test the result with management and stakeholder representatives. Record every change made at validation and who made it.
Map material matters to disclosure requirements
General disclosures under ESRS 2 apply regardless of materiality; topical requirements follow from what is material. Link each disclosure requirement to a data owner, a source system and a first-year data gap.
Impact materiality and financial materiality side by side
| Aspect | Impact materiality | Financial materiality |
|---|---|---|
| Question asked | Does the company affect people or the environment? | Does the matter affect the company's financial prospects? |
| Criteria | Scale, scope, irremediable character; likelihood if potential | Likelihood and magnitude of financial effects |
| Main evidence | Stakeholder input, incident data, supplier audits, scientific sources | Risk register, financial plans, scenario results, lender and customer terms |
| Typical owners | Sustainability, human rights, environment, health and safety | Finance, treasury, enterprise risk, strategy |
| Time horizons | Short, medium and long term, as defined in ESRS 12 | Same horizons: the reporting period, up to five years, and beyond five years2 |
A matter is material if it passes either test. Most climate matters pass both; some community or biodiversity impacts pass only the first, and that is enough.
Documentation to keep for limited assurance
The CSRD requires assurance to cover the process used to identify the information reported, not only the numbers1.
A hypothetical food manufacturer separates the two tests
Questions and answers
How often should a double materiality assessment be refreshed?
Review it every reporting cycle and redo it fully when something significant changes: an acquisition, a new market, a major incident or new evidence about value-chain impacts. A light annual review that records why the conclusions still hold is usually enough in stable years, and it keeps the assurance trail current.
Can we reuse an ISSB or GRI materiality assessment?
Partly. A GRI assessment is built on impact materiality and gives a strong start on the inside-out test. An assessment prepared for IFRS S1 looks at financial materiality from an investor's view. Neither alone meets ESRS, which requires both tests, but combining their evidence avoids starting from a blank page.
What do auditors most often ask about the assessment?
Expect questions on how the long list was built, why thresholds sit where they do, how affected stakeholders were heard, why specific matters were judged not material and how financial scores tie to the risk register. Clear written rationale for exclusions tends to matter more than the visual matrix.
Should the assessment be based on a stakeholder survey?
A survey can inform it, but it should not decide it. Severity and financial effects are judged on evidence; a survey mostly measures awareness. Use targeted engagement with affected groups or their representatives for impact questions, and internal finance and risk experts for financial ones.
Sources
- Directive (EU) 2022/2464 as regards corporate sustainability reporting (CSRD) — EUR-Lex · checked 10 October 2026
- Commission Delegated Regulation (EU) 2023/2772 as regards sustainability reporting standards — EUR-Lex · checked 10 October 2026
- ESRS implementation guidance documents (IG 1 Materiality Assessment) — EFRAG · checked 10 October 2026
- Corporate sustainability reporting — European Commission · checked 10 October 2026
- Directive (EU) 2025/794 amending Directives (EU) 2022/2464 and (EU) 2024/1760 as regards application dates — EUR-Lex · checked 10 October 2026
- Directive (EU) 2026/470 on certain corporate sustainability reporting and due diligence requirements (Omnibus I) — EUR-Lex · checked 10 October 2026