W System / Blog / Denmark: new NemHandel and MitID rules for registered bookkeeping systems (2027-2028)

Denmark's new rules for registered bookkeeping systems: NemHandel, MitID and CVR data (2027-2028)

By Zifeng Wei, W System · Published 2 November 2026 · All articles

In short: Denmark is not introducing a B2B e-invoicing mandate, but it is making registered digital standard bookkeeping systems push e-invoicing. Under executive order no. 811 of 2026 and the Danish Business Authority's guide of 25 September 2026, from 1 March 2027 these systems must validate CVR-registered customers with MitID, register end customers in Nemhandelsregistret (the NemHandel register) unless they opt out within 4 weeks, and show on manual invoices whether the recipient can receive an e-invoice through NemHandel. From 1 January 2028 come locked master data from the CVR register, MitID for bank and identifier changes, searchable records and a ban on deleting documents. If you build accounting or invoicing software sold in Denmark, the 2027 part means a NemHandel lookup in your invoice screen and a registration flow behind it.

The eight requirements and when they apply

From	Requirement
1 Mar 2027	1. One-time MitID validation of every CVR-registered end customer (and the person acting for it), logged with time, type and user. Foreign customers without a CVR number are out of scope.
1 Mar 2027	2. NemHandel registration with opt-out: tell end customers they will be registered in Nemhandelsregistret unless they opt out within 4 weeks, then register them within a further 4 weeks (via the PORS registration API or manually) and notify them straight after.
1 Mar 2027	3. Show the e-invoice option: when a user invoices manually, the system must clearly show that the recipient can receive an e-invoice if the recipient is registered in NemHandel. Batch and API invoicing are exempt.
1 Jan 2028	4. MitID validation when supplementary master data changes (bank details, SE number, GLN).
1 Jan 2028	5. Searchable and exportable records per end customer.
1 Jan 2028	6. Locked master data fetched from the CVR register (name, address, CVR number, P-numbers) that users cannot edit in the system.
1 Jan 2028	7. Outgoing e-documents carry the locked CVR data; the user picks which production unit (P-number) applies.
1 Jan 2028	8. Documents cannot be deleted.

The dates follow the Danish Business Authority's guide for providers. Some of these requirements were originally planned for 1 January 2027 and were moved to 1 March 2027. Separately, the SAF-T export format changes to version 2.1 from 1 January 2027.

NemHandel is not Peppol

NemHandel is Denmark's own e-delivery network and register, run by the Danish Business Authority. Public bodies have received e-invoices through it since 2005, and many businesses are registered too, usually receiving OIOUBL (the Danish UBL profile). Endpoints are often a GLN/EAN number rather than the CVR number. Some participants also accept Peppol BIS Billing 3.0 on Peppol.

That matters for the e-invoice display requirement: a lookup only on Peppol, by CVR number under scheme 0184, can say "not registered" for a company that receives on NemHandel every day. For example, on 2 November 2026 Novo Nordisk A/S (CVR 24256790) was not found on Peppol under 0184, but Nemhandelsregistret listed a NemHandel receiving endpoint under a GLN number for OIOUBL invoices.

How to check the NemHandel register

Nemhandelsregistret has a public lookup API with anonymous access. GET https://api.nemhandel.dk/nemhandel-api/search/lookup/{cvr} returns the company's name and address from CVR and a list of receivers: each with its endpoint key and type (GLN, DK:CVR and so on), the network (NemHandel / AS4 or PEPPOL / AS4), the document standard and the profiles it accepts in the Customer role. A CVR number with no registration returns 404. The register changed the JSON field names to PascalCase on 15 September 2026, so integrations written earlier may need updating. Registering your customers (requirement 2) goes through a different API, PORS, which needs credentials.

curl -s "https://api.nemhandel.dk/nemhandel-api/search/lookup/24256790"

Checklist for bookkeeping and invoicing software

Check whether your system is a registered digital standard bookkeeping system under the Bookkeeping Act; these requirements apply to registered systems.
Look up each Danish recipient in Nemhandelsregistret in the manual invoice flow and show the result clearly, including which endpoint (GLN, CVR, P- or SE-number) receives invoices. Cache it, but refresh it, because registrations change.
Build the opt-out flow: notice, a 4-week opt-out window, registration within a further 4 weeks via PORS (or manually), and a notice after registration. Log what was sent and when.
Add the one-time MitID validation for CVR-registered customers through a MitID broker, and keep the validation log (time, type, user).
Plan for 2028: fetch name, address, CVR and P-numbers from the CVR register and lock them, let users pick the P-unit on outgoing documents, require MitID for bank, SE and GLN changes, and stop documents from being deleted.
Support OIOUBL for NemHandel recipients and Peppol BIS Billing 3.0 for Peppol recipients, and validate files before sending.

Checking Danish buyers with one call

Disclosure: W System, which publishes this page, makes the API mentioned here. GET /einvoice/route?id=DK… checks a Danish VAT number in VIES, looks the CVR number up in Nemhandelsregistret and on Peppol (0184), and returns the receiving endpoints, networks and document standards, with NemHandel recommended first when the company receives there. It also returns the requirement dates above. It does not do MitID validation, NemHandel registration through PORS, or locked CVR master data, and it does not create OIOUBL files; /einvoice/create builds Peppol BIS 3 and EN 16931 UBL, and /einvoice/validate checks UBL and CII files against EN 16931. W System is not a NemHandel or Peppol access point. Free for 20 calls a day per IP; details on the e-invoice API page. Not legal advice.

curl "https://api.wsystem.dev/einvoice/route?id=DK24256790"

Questions and answers

Is e-invoicing mandatory between businesses in Denmark?

No. Denmark has no domestic B2B e-invoicing mandate; e-invoices to public bodies through NemHandel have been mandatory since 2005. The new rules put obligations on providers of registered digital standard bookkeeping systems, not a duty on businesses to send e-invoices to each other. Cross-border B2B digital reporting under the EU's VAT in the Digital Age package applies from 1 July 2030.

Who has to comply with the 2027 requirements?

Providers of digital standard bookkeeping systems registered with the Danish Business Authority (Erhvervsstyrelsen) under the Bookkeeping Act. The requirements come from executive order no. 811 of 2026 and the authority's guide of 25 September 2026, and apply to the system, not to each user. Several requirements were moved from 1 January 2027 to 1 March 2027.

What does 'show the e-invoice option' mean in practice?

When a user creates an invoice by hand, the system must clearly show that the recipient can receive an e-invoice if the recipient is registered in NemHandel. To do that, the system has to look the recipient up in Nemhandelsregistret, which has a public lookup API. Invoices created in batches or through an API are exempt from this display requirement.

How do I check whether a Danish company is registered in NemHandel?

Search by CVR number on the Nemhandelsregistret website, or call the register's public lookup API (api.nemhandel.dk, anonymous access; GET /search/lookup/{cvr}). The answer lists the company's receiving endpoints (often a GLN/EAN number, sometimes the CVR number), the network (NemHandel or Peppol) and the document standard (usually OIOUBL).

Is NemHandel the same as Peppol?

No. NemHandel is the Danish e-delivery network and register run by the Danish Business Authority, mostly carrying OIOUBL documents. Peppol is the European network. A Danish company can be registered on one, both or neither, and a Peppol lookup by CVR number (scheme 0184) can miss a company that receives on NemHandel under a GLN number.

What does the opt-out registration involve?

The system tells each end customer that it will be registered in Nemhandelsregistret unless it opts out within 4 weeks. If it does not opt out, the provider registers it within a further 4 weeks, through the PORS registration API or manually, with the CVR number as the default endpoint (P-number, SE or GLN/EAN are also possible), and notifies the customer straight after.

Sources

Checked against the Danish Business Authority's guide and a live Nemhandelsregistret lookup on 2 November 2026.

Facts checked 2026-11-02. W System is the maker of this product. Not affiliated with the European Commission. Not legal or tax advice.