Denmark: NemHandel BIS 4 transition ahead

What is changing?

Denmark is preparing to phase out OIOUBL 2.1 and move towards NemHandel BIS 4.

NemHandel BIS 4 is based on Peppol BIS 4 and aligns with the European semantic standard EN 16931. The transition is expected to start in 2028 and continue into 2029.

OIOUBL remains active in the short term, but the long-term direction is clear: Denmark is moving closer to European e-invoicing standards.

Why it matters

This is a reason to contact customers with Danish invoice flows and check whether they depend on OIOUBL 2.1.

The transition may affect ERP configuration, e-invoicing platform support, format validation and long-term invoice architecture. Customers with Nordic operations should start monitoring this early, even if detailed technical specifications are still expected.

Start with these customer questions:

– Does the customer currently exchange OIOUBL 2.1 invoices?
– Which Danish entities or flows depend on NemHandel?
– Can the ERP or e-invoicing platform support future NemHandel BIS 4 requirements?
– Is the invoice data model aligned with EN 16931?
– Who monitors updates from the Danish Business Authority?
– Will the transition affect customers, suppliers or internal integrations?

One detail to check carefully

This is a format and infrastructure transition, not a new direct B2B e-invoicing mandate by itself.

Customers should monitor how the transition interacts with Denmark’s Digital Bookkeeping Act and future system requirements.

Talking point

“Denmark is preparing to move from OIOUBL 2.1 to NemHandel BIS 4. Shall we check whether your Danish invoice flows depend on OIOUBL and what this means for your ERP, platform and Peppol readiness?”

What should partners do next?

Contact customers with Danish operations or Nordic invoice flows. Focus on OIOUBL dependencies, NemHandel usage, Peppol alignment, EN 16931 readiness, ERP impact and how Routty can support multi-format e-invoicing transitions.