Education institutions file their annual figures with DUO (the Dutch education executive agency) every year before 1 July, through the XBRL Onderwijsportaal (opens in a new tab) (the DUO education portal), in XBRL based on the OCW taxonomy (the taxonomy of the Dutch Ministry of Education, Culture and Science). In addition, the institution publishes an annual report: the management report with a continuity section, plus the financial statements with WNT accountability (Wet normering topinkomens (opens in a new tab), the Dutch executive-pay standards act). That same report also goes to DUO as a PDF, together with the auditor’s report. The same figures therefore appear in several forms — and those forms have to line up exactly. One more format is coming: for reporting year 2027, Inline XBRL becomes mandatory. This article sets out what has to be filed, how the annual rhythm runs, and what the CVO and DUO pilot teaches about a more structured approach.
What has to be filed and published
Annual figures to DUO. The data from the financial statements goes to DUO as an XBRL file, through the XBRL Onderwijsportaal, using eHerkenning to log in. For reporting year 2025 the applicable taxonomy version is NT20 OCW 20260218, which DUO publishes per sector. Its structure and definitions are fixed in the OCW taxonomy, an extension of the Dutch national taxonomy (Nederlandse Taxonomie) that gets a new version every year (for reporting year 2025 that is NT20 OCW). Every figure has a fixed place and meaning there, so DUO can process and compare the data of all institutions by machine.
OCW Beleidsinformatie. Boards in primary, secondary and senior secondary vocational education file a second XBRL report through the same portal: OCW Beleidsinformatie (policy information). That obligation does not apply to higher education.
Management report with continuity section. Besides the review of the reporting year, the management report contains a mandatory forward look: the continuity section.
WNT accountability. The accountability under the Wet normering topinkomens (executive-pay standards act) is part of the financial statements.
Auditor’s report. The auditor’s report (controleverklaring) is part of the filing, and where the auditor issues one, so is the report of findings (verslag van bevindingen). Those documents go in as PDFs via Mijn DUO, not through the XBRL Onderwijsportaal.
The annual report: published and filed. Management report and financial statements together form the annual report. The institution publishes it in its own brand style, for print and for online use, and keeps it available for at least seven years afterwards. The same report also goes to DUO as a PDF, by 30 June.
The rhythm: every year before 1 July
The 1 July deadline falls at the same moment every year: after the audit and internal adoption. The last weeks before filing are therefore the busiest — and that is precisely when the final corrections come in. At that moment, every change has to land in three places at once: in the financial statements, in the published annual report, and in the XBRL filing. Whoever keeps those three separate ends up checking everything by hand at the finish.
What “without manual rework” is — and is not — about
Producing an annual report remains work. The management report does not write itself, the continuity section calls for real analysis, and review by the board and the auditor is part of the job. No software takes that over.
What can be removed is the manual rework on the data: the same figure entered three times — in the financial statements, in the WNT table, in the XBRL file — and re-checked three times with every late change. When all those forms come from one structured source, a correction lands everywhere at once and that checking work disappears. The gain is in data consistency, not in less thinking.
The pilot: CVO’s annual report in Inline XBRL, together with DUO
Vereniging CVO Rotterdam e.o., a Christian secondary-education school board (a vereniging) running six school groups in and around Rotterdam, produced its 2024 annual report in Inline XBRL based on the OCW taxonomy, with support from its own shared service centre. One document, then, that is both readable by people and processable by machine. On 1 July 2025 CVO published that report publicly and announced it on its own website (opens in a new tab), as one of the first education boards with a public annual report in this format.
In doing so, CVO ran ahead of the timeline DUO is now working towards. That DUO intends this direction is a matter of public record: SBR Vernieuwing and DUO have shown in a completed experiment (opens in a new tab) that a management report is straightforward to produce in iXBRL. Reporting year 2025 is covered by a trial year that starts on 1 September 2026 (moved from 1 July). 2027 is a transition year, and for reporting year 2027 Inline XBRL is mandatory, at the filing in 2028.
At the pilot table sat not only the filing party (CVO) and the auditor, but also DUO as the receiving side. CVO was thereby one of the first boards to take part in Samen Verantwoorden, the programme in which DUO and OCW shape the accountability chain together with school boards and auditors. The filing side and the receiving side looked at the same process together.
Three outcomes from the pilot:
- The design stayed intact. The communications team rebuilt the existing InDesign design in Taxxor Disclosure Manager, so the report looks the same in Inline XBRL as it did before.
- The process is ready for coming years. After the fact, the control team saw the setup virtually ready for the next annual cycle, with communications, finance and control teams working in the same document.
- The OCW taxonomy is proven in production. The pilot tested the taxonomy through a full annual cycle, and it can be enabled in any Taxxor environment.
How Taxxor does this
In Taxxor DM, the financial statements, the WNT accountability and the XBRL filing to DUO all come from the same structured source data. A changed figure is therefore correct in the report, in the accountability and in the filing — even just before the 1 July deadline. The OCW taxonomy can be enabled in any Taxxor environment, the XBRL file is validated before the upload to the Onderwijsportaal, and via the data lineage the auditor can see where every figure comes from. The annual report itself rolls out of the same source: in the brand style, print-ready, as an online PDF and, where needed, as Inline XBRL — so the trial year does not become a separate project.
More about the approach for education institutions is on the education page — or request a demo with the OCW taxonomy.