Denmark: pioneer since 2005

E-invoicing in Denmark: pioneer since 2005, Bookkeeping Act 2022, B2B technical readiness and the planned migration from OIOUBL to Nemhandel BIS 4 (Peppol BIS 4).

Denmark was an absolute pioneer: as early as 2005, e-invoicing to government bodies became mandatory via the NemHandel network and the OIOUBL format. The Danish model is frequently cited internationally as a best practice for implementing mandatory e-invoicing.

Overview
AspectDetailsB2GMandatory since 2005 (OIOUBL/NemHandel)B2BTechnical readiness mandatory (Bookkeeping Act 2022)FormatsOIOUBL, Peppol BIS 3.0 (transition to Nemhandel BIS 4 planned)Peppol AuthorityDigitaliseringsstyrelsen (government) / Erhvervsstyrelsen (Nemhandel BIS 4 strategy)
From NemHandel to Peppol

Denmark started with NemHandel as its national network for e-invoicing to government bodies. The OIOUBL format (a Danish UBL specification) was the standard format. Today, invoicing largely runs through the Peppol network and Peppol BIS 3.0.

The high B2B adoption in Denmark is the result of years of government initiatives and the broad availability of e-invoicing in accounting software.

Bookkeeping Act 2022

Denmark made digital bookkeeping mandatory through the Bookkeeping Act (2022). The implementation phases were completed by January 2026 for most companies. Unlike other European countries, Denmark does not focus on a traditional B2B e-invoicing mandate but on technical readiness: companies must have the technical capability to issue and receive e-invoices as part of digital bookkeeping requirements.

Strategy: from OIOUBL to Nemhandel BIS 4

The Danish Business Authority (Erhvervsstyrelsen) published on 9 March 2026 (version 1.0, version date 5 March 2026) a strategy to phase out OIOUBL in favour of Nemhandel BIS 4 — this is Peppol BIS 4 with mandatory Danish national extension(s) ("dansk minimumsmodel"), conforming to the European standard EN 16931.

Scope: the strategy concerns only the invoice document standard — invoice (faktura), credit note (kreditnota) and invoice response (fakturasvar). Other OIOUBL document types (e-order, e-receipt) remain exchangeable via both OIOUBL and Peppol for now. Message Level Response (MLR) is outside the scope of this strategy.

Why Peppol BIS 4 and not BIS 3? Peppol BIS 3 does not support payment automation via NemKonto and lacks required data elements. An intermediate step via BIS 3 would cause an additional migration. Peppol BIS 4 implements the PINT architecture (Peppol INTernational), allowing countries to add national extensions without breaking international interoperability. The transition aligns with EU ViDA, which mandates cross-border intra-EU B2B e-invoicing from 1 July 2030.

Timeline (conditional — dependent on timely completion by CEN and OpenPeppol):

PeriodStep2026New EN 16931 (CEN/TC-434) and Peppol BIS 4 (target: end of 2026)2027Development of Nemhandel BIS 4 (national extensions)Nov 2027 – May 2028Release candidate comment periodEarly 2028Start of transition to Nemhandel BIS 4May – Nov 2028Indfasning: Nemhandel BIS 4 optional, OIOUBL mandatoryNov 2028Role reversal: Nemhandel BIS 4 mandatory, OIOUBL 2.1 voluntaryNov 2028 – May 2029Udfasning OIOUBL 2.1Mid-2029Full migration expected; OIOUBL support ends

After completion, the Bookkeeping Act requirement (both OIOUBL and Peppol) will be amended to Nemhandel BIS only. Target groups of the strategy: Nemhandel service providers, accounting system vendors and government institutions.

What does this mean for you?

Denmark requires specific schemeIDs (e.g. 0184 for Danish customers since BIS 3.0.20). The eConnect PSB supports these automatically, ensuring your invoices are correctly routed to Danish recipients via the Peppol network.

For compliance and migration planning, the planned transition from OIOUBL to Nemhandel BIS 4 is relevant: full migration is expected towards mid-2029. eConnect monitors these developments and will update the PSB in a timely manner.

Frequently asked questions
Is e-invoicing mandatory in Denmark?

For government suppliers (B2G), e-invoicing has been mandatory in Denmark since 2005, via the NemHandel network and the OIOUBL format. For B2B, the Bookkeeping Act (2022) requires technical readiness: companies must be able to issue and receive e-invoices. Adoption is very high thanks to years of government initiatives and broad software support.

What format is used for e-invoices in Denmark?

Denmark traditionally uses the OIOUBL format, a Danish UBL specification. Today, invoicing largely runs through Peppol BIS 3.0. Denmark is planning a transition to Nemhandel BIS 4 (Peppol BIS 4 with Danish national extensions), expected by mid-2029. Until then, both OIOUBL and Peppol BIS 3.0 remain in force.

Can I send invoices to Denmark via eConnect?

Yes, eConnect supports invoice exchange with Denmark via the Peppol network. The PSB automatically applies the correct schemeIDs (including 0184 for Danish customers) and routes your invoices correctly to Danish recipients.


Want to send invoices to Danish customers? See how eConnect can help.

View the international overview

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