Denmark e-Invoicing Guide

Denmark was a pioneer in e-invoicing, mandating electronic invoices for government suppliers as early as 2005 — making it one of the first countries in the world to do so. The country's NemHandel infrastructure and OIOUBL format have been cornerstones of Danish digital governance for nearly two decades.

While B2B e-invoicing remains voluntary, Denmark has introduced digital bookkeeping requirements under the Danish Bookkeeping Act that effectively push businesses toward digital invoice management. The growing adoption of Peppol alongside NemHandel is preparing the ecosystem for potential future B2B mandates.

Denmark's e-invoicing timeline reflects its early-mover status. B2G has been mandatory since 2005, with the current requirement (via OIOUBL on NemHandel) effective since April 2019. The planned OIOUBL 3.0 update was cancelled in January 2026. Meanwhile, digital bookkeeping requirements for businesses above DKK 300,000 turnover took effect in January 2026.

All government suppliers must submit invoices electronically via NemHandel using the OIOUBL format. B2B e-invoicing is voluntary — businesses can choose to adopt Peppol or OIOUBL for their trading partners, but there is no legal obligation to do so.

Under the Danish Bookkeeping Act, businesses with annual turnover above DKK 300,000 must use approved digital bookkeeping systems. While this does not mandate e-invoicing specifically, it drives adoption of digital invoice handling. B2C transactions are entirely outside any e-invoicing framework, and small businesses below the turnover threshold are exempt from digital bookkeeping requirements.

Denmark uses a decentralized exchange model. Businesses connect to NemHandel or the Peppol network through access points, using CVR numbers for routing. There is no central government clearance or pre-authorization — invoices are exchanged directly between parties through the network.

For B2G, invoices must be in OIOUBL format and submitted via NemHandel. The Peppol network is increasingly used alongside NemHandel for both B2G and voluntary B2B exchange, offering businesses a path to broader European interoperability.

Penalties in Denmark primarily apply to B2G obligations and compliance with the Bookkeeping Act. Government suppliers risk payment delays or invoice rejection for non-electronic submissions, while businesses that fail to comply with digital bookkeeping requirements face fines and potential business registration restrictions.