« CbCR » public tax reporting in the EU: from regulatory framework to the digital report

The EU Public Country-by-Country Reporting¹ (Public CbCR) regime represents an important step in tax transparency, requiring large multinational groups operating in the EU to publicly disclose key tax and business information on a country-by-country basis.

The execution of Implementing Regulation (EU) 2024/2952, requiring an electronic format for the presentation of this report, combined with the recent publication of an associated technical taxonomy, highlights the key challenges for 2026.

Regulatory background

Implementing Regulation (EU) 2024/2952 sets out the technical rules applicable to the « Public CbCR » Directive. Applicable to financial years starting on or after 1 January 2025, it covers multinational groups headquartered in the EU, as well as certain non-EU groups with significant EU operations that meet the thresholds defined in the directive. These rules require multinationals to prepare a public income tax dataset, designed specifically for disclosure purposes rather than regulatory exchange, and to make this information accessible to the public.

Under the regime, in-scope groups must publicly disclose, for each tax jurisdiction in which they operate, both quantitative data and certain qualitative or contextual information, as set out in the underlying directive. This includes information on, business activities, revenues, profit or loss before tax, income tax accrued and paid, number of employees. The structure and content broadly align with the Organisation for Economic Co-operation and Development (OECD) CbCR framework, but the EU regime goes further by requiring the information to be publicly disclosed and presented in a standardised XHTML document with inline XBRL tagging.

Mandatory XHTML and inline XBRL reporting

A core requirement introduced by the regulation is that the Public CbCR report must be prepared in XHTML format and tagged using inline XBRL.

This approach mirrors technical models already familiar to many issuers from ESEF financial reporting (the European Single Electronic Format required for digital annual financial reports of listed companies), combining a human-readable document with structured, machine-readable data. The data published in the report and readable by humans are tagged with computer codes drawn from a dictionary understood by machines, known as a taxonomy.

Important point! : the obligation to publish a Public CbCR report begins earlier than the obligation to apply Inline XBRL. As a result, some companies, particularly those with non-calendar financial year ends (for example, April year-ends), may be required to publish a Public CbCR report before the digital XHTML and Inline XBRL format becomes mandatory. For financial years starting on or after 1 January 2025, however, in-scope groups must both, prepare the Public CbCR report, and publish it in XHTML with Inline XBRL tagging in accordance with the European taxonomy.

The Public CbCR taxonomy

The taxonomy defines a comprehensive set of reportable concepts at jurisdiction level. It is closely aligned with the OECD CbCR framework, while being specifically adapted to meet the EU’s public disclosure objectives and inline XBRL technical requirements. In doing so, it also establishes clear rules to ensure consistency, comparability, and usability of « Public CbCR » data across all reporting entities. In practical terms, the taxonomy transforms the legal obligation into an operational reporting requirement, enabling regulators, analysts, and the public to automatically consume and compare disclosed data.

Alongside the publication of the taxonomy, the European Commission has also released an inline XBRL report generator to help companies and software providers convert their reports into the required format. The generator is designed as a technical aid to illustrate how the taxonomy can be applied in practice, facilitating the creation of compliant XHTML reports with Inline XBRL tagging. While the tool is not a mandatory solution, it provides a useful reference for understanding the structure of the taxonomy, validating tagging approaches and accelerating readiness for Public CbCR reporting.

Start preparing now

With both the Directive obligations and the Implementing Regulation now in place, European « Public CbCR » requirement is clearly moving from a conceptual requirement to an operational reality. Companies should begin by assessing whether they fall within scope, performing gap analyses between internal CbCR data and the EU public reporting requirements, and putting in place processes, tools and controls to support inline XBRL-based publication.

The RegTech team at BM&A, specialists in digital reporting and XBRL technologies, supports clients with the practical implications of European Public CbCR, including taxonomy interpretation, data preparation and XHTML / Inline XBRL implementation.

¹ Framework introduced by European Directive (EU) 2021/2101, applicable to financial years starting on or after 22 June 2024.