The Register of Foreign Service Providers (RUT) is the Danish government's official register to report a foreign service. Foreign service providers (employees and self-employed) working in Denmark must register in RUT. For self-employed you only have to register if the service falls within selected sector codes (general building and construction work or installation and repair of machinery and equipment).
This also applies to companies that do not have real activities in their home country.
If you have not registered a service before, you should start by setting up a user account. Click on the 'Start' icon or log in with a digital signature or MitID Erhverv.