Denmark: OIOUBL 2.1 Schematron Version 1.16.0.RC Released

Denmark’s Business Authority has released Schematron version 1.16.0.RC for OIOUBL 2.1, introducing enhanced validation for CO₂ data, stricter currency code enforcement, and overall data quality improvements in e-invoices. The final version is expected by late October 2025, with mandatory implementation set for 27 November 2025

The Danish Business Authority has published Schematron version 1.16.0.RC for OIOUBL 2.1, introducing minor updates to improve data quality, CO₂ reporting, and currency code validation in electronic invoices.

Updates in Version 1.16.0.RC:

1.      Support for CO₂ data in E-Invoices

-       The new version adds validation checks for environmental and CO₂-related data within invoices.

-       These fields are optional, but if used, the schematron ensures they are applied correctly.

-       Technical documentation: OIOUBL Billing with Environmental Data

2.      Stricter currency code validation

-       The update tightens existing rules requiring that all monetary amounts include a valid currency code.

-       This has always been mandatory under OIOUBL but was only partially enforced in earlier schematron versions.

3.      Technical Improvements

-       Minor data quality and validity checks have been added.

-       The changelog with full technical details is available here.

-       The schematron package can be downloaded here.

Implementation timeline

-       Release candidate issued: 14 October 2025

-       Expected final release: End of October 2025 (unless significant objections are raised)

-       Implementation deadline: 27 November 2025

The shorter release-candidate period was intentional to avoid implementation deadlines in December, which could complicate accounting and year-end activities.

OIOUBL Schematron v1.16.0.RC refines data validation for Denmark’s e-invoicing framework by:

 -       Introducing checks for optional CO₂ and environmental data,

-       Enforcing currency code compliance, and

-       Enhancing invoice data quality overall.

Final approval and mandatory implementation are expected by late November 2025