Electronic invoicing in the EU and Denmark

December 5th, 2018

Electronic invoicing in EU and Denmark

On April 18, 2019, the new rules on electronic invoicing in the EU applies – initially for the state authorities. This has implications for the exchange of electronic invoices and credit notes between the EU countries, but also within Denmark.

The Legislation

The European standard for electronic invoicing (CEN/EN 16931-1: 2017) determines, which elements an electronic invoice and credit note must and should contain, and that they must be sent as a UBL document (ISO/IEC 19845) or as a Cross Industry Invoice (CII).

The standard is only binding on public authorities in the EU and only on public tenders above the EU tender limit. For state authorities, the standard applies from 18 April 2019 and for regional and municipal authorities from 18 April 2020.

The consequences of the new legislation are that the public authorities in Denmark and the EU must prepare to receive and process an invoice or credit note;

  • which as a minimum contains the information that is mandatory in the law, and maximum the information described in the law.
  • which complies with one of the two formats UBL or CII with the fields described in the law.
  • which both can have positive and negative totals.

As part of the EU legislation, it is described how, for example, in an industry or nationally, the legislation can be tightened through a “Core Invoice Usage Specification” (CIUS) or extensions to it (Extensions). There are currently no planned Extensions in Denmark.


OpenPeppol is an international “non-profit” organization whose purpose is to support the exchange of electronic business documents across national borders.

OpenPeppol has updated their business documents in accordance with the EU law by creating a CIUS that further clarifies the requirements for the use of an UBL invoice and credit note. The CIUS is described as “Peppol BIS Billing“.

In addition to the documents, Peppol has also an infrastructure for exchanging them, and it is expected that, in practice, the Peppol BIS Billing documents will be exchanged between countries rather than documents based on the EU law alone.

It is not possible for national authorities to demand requirements on foreign suppliers in addition to the rules described in the European standard. However, it is possible in Peppol BIS Billing to tighten the requirements nationally so that Danish suppliers using Peppol BIS Billing must comply with additional rules. The national rules can be seen together with the other “rules for Peppol BIS Billing“.

The consequences of Peppol BIS Billing include;

  • that it replaces the existing Peppol invoice and credit note (BIS2), and no later than 18 April 2019, senders and recipients of Peppol invoice and credit note must be ready to process the new format.
  • that the content of the documents contains several changes, including new elements and classes and elements that are no longer allowed, and changes to code lists.
  • that a Peppol invoice and credit note may have negative signs.
  • that the sender must comply with any national rules embedded in Peppol BIS Billing.


Danish suppliers can still use OIOUBL invoice and credit note when they send to Danish authorities.

The EU standard and the changes to Peppol will, however, also have an impact on OIOUBL invoice and credit note, since the Danish Business Authority has decided to adjust OIOUBL to offset the main differences between EU/Peppol and OIOUBL. This is partly due to the fact that in the long term they are working towards phasing out OIOUBL in favour of Peppol, and partly that there will initially be a need to convert a Peppol invoice or credit note to OIOUBL.

Some changes to OIOUBL as a result of the EU standard are implemented with schematron release 1.10 (September 15, 2018), while most will be implemented with schematron 1.11, which releases on March 15, 2019. The main changes are;

  • Payments (PaymentMeans) – in EU/Peppol, payments are largely based on the recommendations from SEPA (Single Euro Payments Area). This means, for example, that two new SEPA payment methods are allowed for account transfer and Direct debit, and that some changes are made to the use of the elements under the PaymentMeans class in order to be able to map from the Peppol documents.
  • MimeCodes – it is allowed to embed some new document types as they are added in the EU standard.
  • VAT in other currency – the use of TaxCurrencyCode is adjusted, so that no requirements are made for filling in so many other fields as it is the case today. Only in cases where an invoice is in a currency other than DKK or EUR, the VAT must be stated in either DKK or EUR.
  • Negative amount – unlike Peppol, it is not allowed to send a negative invoice or credit note in OIOUBL. On the other hand, it becomes necessary to allow some more amounts to be negative so that it becomes possible to convert a negative Peppol invoice to an OIOUBL credit note.

Together with the schematron release on March 15, 2019, a Danish “CIUS Package” will also be released which will include:

  • A description of the main differences between Peppol and OIOUBL, mapping examples, description of the national Danish rules in Peppol BIS Billing and more.
  • A stylesheet for conversion between Peppol BIS Billing and OIOUBL.
  • A HTML display style sheet for Peppol BIS Billing with Danish adjustments.
  • Sample files.

Information about OIOUBL schematron and Dansk CIUS will be published on Digitaliser.dk.

Contact us for more information, email: info@mysupply.dk, tel: (+45) 9696 1070.

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