The Corporate Sustainability Reporting Directive (CSRD), published as Directive 2022/2464 in the Official Journal of the European Union, is the most far-reaching overhaul of corporate reporting obligations in Europe since the introduction of IFRS accounting standards. Replacing the earlier Non-Financial Reporting Directive (NFRD), the CSRD expands the scope of mandatory sustainability reporting from approximately 11,700 companies to nearly 50,000 across the EU — bringing thousands of companies into a reporting regime for which they have little or no prior experience.
What CSRD Requires: The ESRS Standards
The substantive content of a CSRD-compliant sustainability report is defined by the European Sustainability Reporting Standards (ESRS), adopted via Commission Delegated Regulation (EU) 2023/2772. The ESRS are structured in two tiers:
Cross-cutting standards: ESRS 1 (general requirements covering the architecture and principles of ESRS reporting) and ESRS 2 (general disclosures on governance, strategy, impact and risk management, and metrics and targets). ESRS 2 is mandatory for all in-scope companies regardless of materiality.
Topical standards: these cover environmental matters (ESRS E1 on climate change, E2 on pollution, E3 on water and marine resources, E4 on biodiversity, E5 on circular economy), social matters (ESRS S1 on own workforce, S2 on workers in the value chain, S3 on affected communities, S4 on consumers and end-users), and governance (ESRS G1 on business conduct). Applicability of each topical standard is determined by the double materiality assessment.
The Double Materiality Assessment: The Non-Negotiable Starting Point
Double materiality is the conceptual centrepiece of the CSRD framework and the element most likely to be underestimated by companies approaching their first reporting year. Unlike GRI or SASB standards, which focus primarily on financial materiality (how ESG factors affect the company), the CSRD requires companies to assess both dimensions simultaneously:
Financial materiality: Does a sustainability matter create real or potential risks or opportunities that could affect the company’s financial position, performance, cash flows, access to capital or cost of capital?
Impact materiality: Does the company’s own activities or its value chain generate actual or potential impacts on people or the environment that are severe, widespread or irreversible?
A matter that is material on either dimension — or both — triggers the disclosure requirements of the applicable ESRS. The double materiality assessment must be documented in a manner that can be reviewed by the independent verifier and must itself be disclosed as part of the report. Regulators and auditors will scrutinise this process carefully, particularly in early years when companies are establishing precedents.
Building Internal Governance for ESG Reporting
A CSRD report cannot be produced by the communications team alone. It demands a cross-functional governance structure with real authority and data access. The key elements are:
Sustainability Committee: a cross-departmental body with a formal mandate from the Board, responsible for approving the materiality assessment, validating ESG targets and overseeing the reporting process. Board-level oversight of sustainability matters is itself a disclosure requirement under ESRS 2.
ESG or Sustainability Officer: a dedicated role — ideally full-time in companies above a certain size — with direct access to senior leadership and the ability to coordinate data collection across finance, operations, HR and legal.
Data map: a living document that identifies every KPI required by the applicable ESRS standards, the internal system or source (ERP, HR platform, utility invoices, supplier questionnaires), the individual responsible for its collection, and the update frequency required to support quarterly or annual monitoring.
The Two Hardest Standards in Year One: ESRS E1 and ESRS S1
In practice, companies preparing for their first CSRD reporting year consistently find the greatest difficulty in two areas:
ESRS E1 (Climate Change): requires disclosure of greenhouse gas emissions across Scopes 1, 2 and 3, a climate transition plan aligned with the Paris Agreement’s 1.5°C pathway, and financial risk and opportunity analysis using climate scenarios. Scope 3 emissions — indirect emissions across the full value chain — are typically the most complex to measure and, for most businesses, the largest in absolute terms. Many companies will need to issue questionnaires to key suppliers and use spend-based or industry-average emission factors where primary data is unavailable.
ESRS S1 (Own Workforce): requires detailed workforce disclosures including the gender pay gap, the ratio between CEO pay and median employee pay, headcount by employment type, health and safety incident rates, and information on collective bargaining coverage. In Spain, part of this data is already captured in mandatory pay registers required under Royal Decree 902/2020 on equal pay, giving companies a useful starting point.
Verification Requirements and Legal Responsibility
The CSRD mandates that sustainability reports be verified by an accredited independent auditor or verifier. In the first phase of implementation, a limited assurance level is required, with the expectation that this will evolve toward reasonable assurance as reporting practices mature. The Spanish audit regulator (ICAC) published initial guidance in 2024 on the accreditation requirements for sustainability verifiers, clarifying that statutory auditors may also provide sustainability verification if they meet the specific competence requirements.
The sustainability report must be published as an integrated section of the management report (informe de gestión), filed together with the annual accounts at the Companies Registry in XHTML format using the European Single Electronic Format (ESEF) taxonomy. This technical requirement adds a layer of preparation — taxonomy mapping, XHTML tagging and validation — that should not be left to the final weeks before filing.
A Practical Timeline for Companies Reporting on FY 2025
For companies entering CSRD scope for financial year 2025, the preparation window is already running. A realistic calendar looks like this:
- Q1 2025: Complete the double materiality assessment and establish governance structure.
- Q2 2025: Implement data collection systems for material indicators; begin Scope 3 data collection from key suppliers; review and update internal data ownership.
- Q3 2025: Conduct a mid-year data quality review to identify gaps and correct methodology before year-end.
- Q4 2025: Close the full-year dataset, prepare the report draft and begin the independent verification process.
- Q1 2026: Finalise the report, complete XHTML tagging and file with the Companies Registry.
The first CSRD reporting year will be the most demanding. Companies that invest now in rigorous data infrastructure, clear internal accountability and a credible materiality process will not only meet their legal obligations — they will produce disclosures that differentiate them in the eyes of investors, lenders and key customers who are increasingly using sustainability data as a factor in their own decision-making.
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