As Denmark will implement the final phase of its Digital Bookkeeping Act in 2026, its e-invoicing framework also continues to evolve. Following the announcement in 2024 of upcoming changes to OIOUBL, the national e-invoicing format, and then earlier in 2026 the cancellation of the planned OIOUBL 3.0 implementation, a new e-invoicing standard and implementation roadmap were unveiled on February 24 at the Nemhandel Forum.
Nemhandel BIS 4 = EN 16931 + Peppol
During the event, ERST, the Danish Business Authority, officially re-confirmed that the release of OIOUBL 3.0 is cancelled.
In order to converge towards and anticipate ViDA implementation, OIOUBL 3.0 will be replaced by Nemhandel BIS 4 (also called Nemhandel 4.0), which will be based on:
- The new EN 16931 standard (core semantic officially approved on January 2026),
- Peppol BIS 4.0 for which OpenPeppol initiated a workgroup, merging the adoption of the EN 16931 update together with a general shift to a “PINT”-like (Peppol INTernational) methodology
One of the key pending questions relates to the infrastructure and network that will be used once Nemhandel BIS 4 is implemented, particularly the potential migration to the Peppol network, which could simplify the management of both domestic and cross-border e-invoicing.
Global migration plan towards Nemhandel BIS 4
The cancellation of OIOUBL 3.0 means that OIOUBL 2.1 will remain the main e-invoicing standard in Denmark for several more years and will need to continue evolving through updates in order to remain a living standard.
In this context, the Danish Business Authority published a communication on March 3, 2026 [↗︎], announcing that the implementation date for the OIOUBL 2.1 schematron version 1.17.1 has been postponed to May 18.
Nevertheless, the migration to Nemhandel BIS 4 will proceed and is expected to take place in several phases:
- January 2026 – July 2027: Monitoring of the final approval of the new EN16931 standard (expected by mid-2026) and definition of the Peppol PINT / BIS 4.0 e-invoicing standard, with work planned until July 2027.
- January 2026 – December 2027: A dedicated workgroup will work on defining the Nemhandel BIS 4 e-invoicing standard.
- January 2028 – July 2029: Migration to the Nemhandel BIS 4 e-invoicing standard. This phase will also include a shift from an opt-in to an opt-out registration model, meaning that companies will be automatically registered in Nemhandel unless they explicitly opt out.
- July 2029: The OIOUBL 2.1 e-invoicing standard will be phased out
- July 2030: Deadline for the implementation of ViDA
Further details regarding the infrastructure and the precise implementation timeline are still expected. In particular, additional clarification will be needed on the rollout phase between January 2028 and July 2029, as well as on the specifications of the Nemhandel BIS 4 standard.
