The RUT register, explained.

The notification duty derives from § 7a of the Danish Posting of Workers Act, implementing Directive 96/71/EC as revised by Directive (EU) 2018/957, together with the Enforcement Directive 2014/67/EU. RUT is Denmark's instance of a filing that exists, in national variants, across the EU and EEA — Belgium's Limosa, France's SIPSI, Sweden's posting register are its counterparts.

Its function is supervisory: the register tells the Danish authorities — and, by design, the social partners — that posted workers are present, so that the working conditions the Act guarantees can be verified. It should not be confused with the A1 certificate, which documents the applicable social security legislation under Regulation (EC) 883/2004 and is issued by the home state. The two instruments answer different legal questions and a compliant posting to Denmark will ordinarily require both.

For an undertaking with employees, § 7a requires the company's name, business address, contact details, home-state registration and industry code; the dates and place of the service delivery and the Danish recipient's CVR number; the identity of each posted worker and the duration of each posting; the workers' social security registration; and a contact person, appointed among the persons working in Denmark on the assignment. Self-employed providers file the same particulars without the employee data.

Since 1 January 2026, where the posting involves third-country nationals, the undertaking must additionally upload to RUT the service contract with the Danish recipient, the employment contracts, and the workers' residence and work permits (LOV 1458/2024; BEK 1321/2025). The amendment, adopted within a broader package against social dumping, ties the immigration file to the posting file. The two can no longer be run on separate tracks.

Denmark places a statutory duty on the recipient of the service — a feature few other regimes share. In construction and civil engineering, in agriculture, forestry and horticulture, and in cleaning, the Danish recipient (undertaking or private individual, irrespective of the size of the job) must receive documentation of the provider's RUT registration no later than when the service begins.

If documentation has not been received — or is incomplete or incorrect — the recipient must contact Arbejdstilsynet no later than three days after delivery of the service began (§ 7d, stk. 2). Failure to do so is sanctioned with a fine, in practice DKK 10,000, imposed on the recipient.

For procurement, HR and facilities functions inside Danish undertakings, this is operational: engaging a foreign subcontractor in a covered sector creates a verification duty on your side of the contract. The RUT receipt belongs in the onboarding file alongside the contract and the insurance certificate.

Arbejdstilsynet supervises the register and pairs RUT data with site inspection. Fines follow settled practice at DKK 10,000 for a missing, late or materially incorrect notification and DKK 20,000 in repeat cases; the Act treats intent, gross negligence and financial gain as aggravating (§ 10a). Non-compliance with an order can attract daily penalty payments.

The regime has tightened in two steps. Since 1 January 2025, any person performing work for a foreign service provider must be able to present valid identification to Arbejdstilsynet on inspection, and SIRI holds parallel identification powers under the Aliens Act. Since 1 January 2026, the document-upload duty gives inspectors sight of contracts and permits before a site is visited.

RUT is, deliberately, partly public: company identity, service periods and industry codes are searchable. In the Danish institutional context this serves a defined purpose — it enables the trade unions to establish which foreign providers are operating in Denmark.

Denmark has no statutory minimum wage and does not extend collective agreements by law. No host-state pay rate applies automatically to a posted worker. The Act instead channels the pay question through the Danish model: under § 6a, a Danish trade union may take collective action against a foreign provider to obtain a collective agreement, provided the wage demand rests on the nationwide agreements of the most representative social partners and is stated with the requisite clarity.

Statutory protection is nonetheless substantial. From day one the posted worker is covered by the Working Environment Act, the working-time rules and the equal-treatment and anti-discrimination legislation; postings beyond eight days attract supplementary holiday rights up to the level of the Danish Holiday Act where home-state rules fall short (§ 6). Beyond twelve months — or eighteen, where the extension was notified in time — essentially all Danish employment law applies.