CSRD Double Materiality Assessment: A Step-by-Step Guide for Manufacturers

Double materiality is the gateway to your entire CSRD report. Get the assessment wrong and you'll either over-report on irrelevant topics or miss the disclosures your assurance provider will flag. This guide walks through the two-test framework, stakeholder engagement, and documentation requirements under ESRS 1.

What is double materiality under CSRD?

The Corporate Sustainability Reporting Directive (CSRD) requires in-scope companies to prepare a sustainability statement as part of their management report. Before writing a single disclosure, companies must first determine which sustainability topics are material to them — this is the double materiality assessment.

"Double" refers to the two lenses through which you evaluate each topic:

• Impact materiality: Does this company cause, contribute to, or is it directly linked to significant actual or potential impacts on people or the environment? This is an outside-in look from the world's perspective.
• Financial materiality: Could this sustainability issue materially affect the company's cash flows, revenue, costs, access to finance, or reputation in the short, medium, or long term? This is an inside-out look from the investor's perspective.

A topic qualifies as material if it passes either test. You do not need both. This is one of the most common misunderstandings in double materiality practice: companies sometimes conduct the impact test, find a topic passes, and still question whether it belongs in the report because it doesn't create obvious financial risk. Under ESRS 1, passing the impact test alone is sufficient for materiality.

Step 1 — Build your long-list of sustainability topics

ESRS 1 Appendix A provides a mandatory starting point: a list of sustainability matters across all ESRS topics (environmental, social, governance). Your long-list must cover at minimum all the topics in that appendix. You can add sector-specific or company-specific topics on top.

For a typical manufacturer exporting to the EU, the long-list will include 80–120 sustainability sub-topics across climate, pollution, water, biodiversity, circular economy, own workforce, value chain workers, communities, and governance.

Filtering the long-list

Before scoring, do a rapid relevance filter. Topics with zero plausible connection to your business (e.g. marine biodiversity impacts for a landlocked metal-stamping facility) can be de-scoped at this stage — but document the reasoning. Assurers will check that de-scoped topics were considered, not simply omitted.

Step 2 — Score impact materiality

For each topic remaining on your list, evaluate your company's actual and potential impacts using the ESRS 1 criteria:

• Scale: How severe is the impact on people or the environment?
• Scope: How widespread is the impact — how many people or how much of the environment is affected?
• Irremediability: How difficult is it to reverse or remediate the impact?
• Likelihood: For potential (not yet actual) impacts — how probable are they?

Score each criterion on a consistent scale (typically 1–5 or 1–10). Multiply or aggregate the scores to produce a composite impact-materiality score for each topic. Set a threshold above which a topic is deemed impact-material. Document the threshold and the rationale for it.

Step 3 — Score financial materiality

Financial materiality under ESRS follows a similar but distinct logic. For each sustainability topic, assess whether it gives rise to risks or opportunities that could materially affect your financial position, financial performance, or cash flows.

The time horizon matters here. ESRS 1 requires you to consider short-term (up to 1 year), medium-term (1–5 years), and long-term (beyond 5 years) horizons. A topic that creates no current financial risk may still be financially material over the long term — for example, physical climate risks to your production facility under a 2°C warming scenario.

Financial risk and opportunity categories

Common financially material sustainability topics for manufacturers include:

• Carbon pricing risk (CBAM, EU ETS, national carbon taxes) affecting input costs or export costs
• Energy transition risks from stranded fossil-fuel-dependent assets or processes
• Water scarcity risks in regions where your facilities or key suppliers operate
• Supply chain disruption risks from climate-related extreme weather events
• Regulatory compliance costs from EUDR, CSRD supply-chain data requirements, PPWR/EPR packaging obligations
• Revenue opportunities from low-carbon product lines, green procurement tender eligibility, and sustainability-linked financing

Step 4 — Conduct stakeholder engagement

ESRS 1 explicitly requires stakeholder engagement as part of the materiality process. You must identify and consult "affected stakeholders" (those impacted by your business activities) and "users of sustainability statements" (investors, lenders, rating agencies).

In practice, most manufacturers run two to three workshops:

1. An internal workshop with the management team, covering financial materiality topics and risk perspectives
2. An internal workshop with operational/sustainability teams, covering impact materiality and day-to-day ESG risks
3. An external survey or interview round with key suppliers, customers, or community representatives

Document everything. Assurance providers will ask for attendee lists, meeting notes or survey response summaries, and evidence that stakeholder input was factored into the final materiality conclusions. A post-it note exercise that was never documented will not survive limited assurance.

Step 5 — Validate, sign off, and map to ESRS

Once scoring is complete, present the draft material topics list to senior management or the board sustainability committee for sign-off. This step is important for two reasons: it creates a formal governance record, and it aligns the business on what will and won't be reported — which drives resourcing decisions for data collection.

Mapping material topics to ESRS disclosure requirements

After sign-off, map each material topic to the relevant ESRS standard and its mandatory disclosure requirements (MDRs). This mapping becomes the core of your CSRD reporting scope — it tells your finance and sustainability teams exactly which data points to collect and which policies, targets, and actions to document.

Topics that pass materiality trigger both the topical ESRS standard's application requirements and its disclosure requirements. Topics that did not pass materiality do not require detailed disclosures — but ESRS 1 still requires you to explain why they were assessed as non-material, so keep your scoring documentation.

Documentation that survives third-party assurance

Your double materiality assessment will be reviewed by a third-party assurance provider as part of the CSRD audit. The evidence file they expect includes:

• The long-list of sustainability topics considered (with de-scoping rationale for anything removed)
• The scoring matrix with criteria, scores, and thresholds for both impact and financial materiality
• Stakeholder engagement records (workshop minutes, survey summary, respondent list)
• Management or board sign-off on the final material topics list
• The mapping from material topics to ESRS disclosure requirements
• A version history showing how the assessment evolved (particularly if it was updated after initial stakeholder feedback)

Building this documentation file as you go through the process — rather than reconstructing it afterwards — is the single most effective way to reduce the time and cost of your assurance engagement.