On 21 April 2026, the European Securities and Markets Authority (ESMA) published the 2025 European Single Electronic Format (ESEF) XBRL taxonomy files alongside an updated ESEF Conformance Suite. These materials are designed to help issuers and software vendors prepare their 2026 IFRS consolidated financial statements using the most current version of the ESEF format.
The update is significant because it introduces IFRS 18 — Presentation and Disclosure in Financial Statements — into the ESEF architecture. For reporting teams, data architects, and compliance professionals working across machine-readable reporting workflows, this taxonomy release has direct operational consequences.
What is the ESEF and why does the taxonomy matter?
The European Single Electronic Format is the mandatory reporting format for issuers with securities traded on EU regulated markets. Under the ESEF Regulation — derived from the Transparency Directive (Directive 2004/109/EC) — all annual financial reports must be prepared in XHTML, with IFRS consolidated financial statements tagged using Inline XBRL (iXBRL).
The ESEF taxonomy is the structured dictionary that defines which financial data points can be tagged in these reports. It is an extension of the IFRS Accounting Taxonomy maintained by the IFRS Foundation, and ESMA updates it annually to reflect changes in international accounting standards. When the taxonomy changes, every issuer’s tagging process, software configuration, and validation workflow must be updated accordingly.
What has changed in the 2025 taxonomy
Dual entry points for IAS 1 and IFRS 18
The 2025 taxonomy includes two separate entry points, allowing issuers to tag their reports under either IAS 1 (the current standard) or IFRS 18 (the replacement standard effective from 1 January 2027). This dual-track structure supports early adopters while maintaining backward compatibility.
No further ESEF RTS or taxonomy amendments in 2026
ESMA has confirmed that it does not plan to amend the ESEF Regulatory Technical Standards or the taxonomy during 2026. This follows the IFRS Foundation’s decision not to issue a 2026 IFRS Accounting Taxonomy update, providing issuers with a stable regulatory window for implementation.
Updated conformance suite
The ESEF Conformance Suite has been refreshed to align with the 2025 taxonomy. Software vendors and issuers can use it to validate that their tagging and rendering processes meet the current specification.
Understanding the dual entry point architecture
The most technically consequential change in the 2025 taxonomy is the introduction of two parallel entry points. This approach reflects the transition from IAS 1 to IFRS 18, which replaces it as the primary standard governing how financial statements are presented.
IAS 1 — current standard
The existing presentation framework used by most issuers today. Companies that do not early-adopt IFRS 18 will continue to use this entry point for their 2025 and 2026 financial year filings. No changes are required to existing tagging workflows.
IFRS 18 — early adopters
Companies choosing to apply IFRS 18 ahead of its mandatory effective date (1 January 2027) must use this entry point. It introduces restructured profit-or-loss categories, new mandatory subtotals — operating profit and profit before financing and income taxes — and management-defined performance measure disclosures.
Critically, ESMA does not permit the concurrent use of both entry points within a single ESEF filing. Issuers must select one framework and apply it consistently across the entire report.
What is IFRS 18 and why does it matter for digital reporting?
IFRS 18, issued by the International Accounting Standards Board (IASB) in April 2024, replaces IAS 1 as the standard governing the presentation and disclosure of information in financial statements. While the bottom line — net profit — remains unchanged, the structure of the income statement changes substantially.
The standard introduces three new categories for classifying income and expenses in the statement of profit or loss: operating, investing, and financing. It also mandates two new subtotals — operating profit and profit before financing and income taxes — that must appear in every income statement. In addition, entities that use non-IFRS performance measures in public communications must now disclose and reconcile these “management-defined performance measures” within the IFRS financial statements themselves.
For digital reporting, these structural changes have a cascade effect. The XBRL taxonomy elements mapped to the income statement must accommodate the new categories and subtotals. Tagging templates, validation rules, and rendering logic all require updating. Organisations that have built automated data management pipelines for ESEF filing will need to account for both the old and new structures during the transition period.
Implementation timeline
September 2025
ESMA publishes draft amendment to the ESEF RTS incorporating the 2025 IFRS taxonomy, including both IAS 1 and IFRS 18 entry points.
April 2026
ESMA releases the final 2025 ESEF XBRL taxonomy files and updated Conformance Suite. Issuers and vendors can begin integrating the new taxonomy into their workflows.
2026 reporting cycle
Issuers preparing annual financial reports for financial years beginning on or after 1 January 2025 may use either the 2024 or 2025 ESEF taxonomy. No further taxonomy or RTS changes are planned by ESMA during 2026.
1 January 2027
IFRS 18 becomes mandatory for all annual reporting periods. Issuers must transition from IAS 1 to IFRS 18 with retrospective restatement of comparatives.
Implications for issuers and software vendors
The 2026 stability window — with no planned RTS or taxonomy amendments — is strategically important. It gives reporting teams and technology providers a clear runway to prepare for the mandatory IFRS 18 transition in 2027 without having to absorb additional taxonomy changes in parallel.
ESMA recommends early preparation
ESMA encourages issuers and software providers to consult the IFRS Foundation’s guidance on the use of the 2025 IFRS Accounting Taxonomy for 2026 reporting periods. Stakeholders may also contact [email protected] with questions or feedback.
For issuers, the practical considerations include assessing whether early adoption of IFRS 18 is appropriate given their reporting calendar, investor expectations, and system readiness. Companies considering early adoption face a different set of tagging requirements — including new mandatory mark-up elements designed specifically for the IFRS 18 structure — and must ensure their XBRL rendering processes reflect the restructured income statement.
For software vendors, the dual-framework architecture means supporting both entry points simultaneously until IAS 1 is fully retired. Conformance testing against the updated suite is essential before releasing updated tooling to clients.
Practical steps for the transition
Review the 2025 taxonomy
Download the taxonomy files from ESMA and map the differences between IAS 1 and IFRS 18 entry points against your current tagging templates.
Run the conformance suite
Validate your reporting pipeline against the updated Conformance Suite. Identify any rendering or validation failures introduced by the new taxonomy elements.
Decide on early adoption
Evaluate whether early application of IFRS 18 is viable for your 2026 filing. Consider the new income statement structure, retrospective restatement requirements, and investor communication.
Align with sustainability reporting
ESMA has also consulted on extending ESEF to sustainability reporting under ESRS. Ensure your digital reporting infrastructure can accommodate both financial and non-financial tagging requirements.
The broader regulatory context
The 2025 ESEF taxonomy update does not exist in isolation. It sits within a rapidly evolving landscape of digital reporting requirements across the EU. ESMA’s December 2024 consultation on extending ESEF to sustainability reporting — covering XBRL tagging of ESRS disclosures and amendments to the European Electronic Access Point (EEAP) RTS — signals that the scope of structured, machine-readable corporate reporting is expanding beyond financial statements.
Simultaneously, the IFRS Foundation’s work on sustainability disclosure standards under the ISSB is shaping how climate and broader sustainability data will be structured for digital consumption globally. For organisations operating across multiple reporting frameworks — SFDR, CSRD/ESRS, ISSB, and now an evolving ESEF architecture — the challenge is maintaining coherent data infrastructure that can serve each framework’s tagging, validation, and submission requirements from a single source of truth.
At Generation Impact Global, we build data management and reporting technology that supports organisations in navigating exactly this complexity — from structured ESG data collection through to framework-aligned outputs across multiple jurisdictions and standards.
Frequently asked questions
What is the ESEF taxonomy?
The ESEF taxonomy is a structured dictionary of financial data elements used to tag IFRS consolidated financial statements in annual reports prepared in the European Single Electronic Format. It is based on the IFRS Accounting Taxonomy maintained by the IFRS Foundation and is updated annually by ESMA to reflect changes in international accounting standards.
What has changed in the 2025 ESEF taxonomy?
The 2025 taxonomy introduces dual entry points to support both IAS 1 and IFRS 18. IFRS 18 replaces IAS 1 as the standard for financial statement presentation from 1 January 2027, but early application is permitted. ESMA has also confirmed no further taxonomy or RTS amendments during 2026.
Can issuers use both entry points in the same report?
No. ESMA does not permit the concurrent use of both the IAS 1 and IFRS 18 entry points within a single ESEF filing. Issuers must select one framework and apply it consistently across the entire annual financial report.
When does IFRS 18 become mandatory?
IFRS 18 is effective for annual reporting periods beginning on or after 1 January 2027. Early application is permitted, and entities that adopt early must disclose this in their notes. The EU endorsement process was expected to be finalised in early 2026.
How does this affect sustainability reporting under ESRS?
The 2025 ESEF taxonomy update focuses on financial statements. However, ESMA has separately consulted on extending ESEF to sustainability reporting, which would introduce XBRL tagging for ESRS disclosures. Organisations should plan their digital reporting infrastructure to accommodate both financial and sustainability tagging requirements.
