Danish Work Requirements
The question, whether you need a permit depends on a nationality and qualifications for the applicants.
Citizens from the Nordic countries, the European Union (EU) European Economic Area (EEA) and Switzerland are free to reside and work in Denmark. If you wish to reside in Denmark for more than three months, you must apply for a registration certificate at the International Citizen Service or the Regional State Administration (Statsforvaltningen).
Non EU/EEA citizens
In the case of citizens from outside the Nordic countries and the EU/EEA, you must apply for a residence and work permit before starting working. It is the applicant`s responsibility to obtain this permit. If you already legally reside in Denmark, it is possible to submit the application for a residence and work permit at the Danish Agency for Labour Market and Recruitment online via Newtodenmark.dk or at the local police station. Whether you can obtain a residence and work permit depends, first and foremost, on your qualifications.
If you remain in Denmark after your visa expires or if you attempt to use your visa stay to obtain permanent or long-term residency in Denmark, you can be given a penalty period of three or five years. During the penalty period you will not be able to obtain a visa to visit Denmark. Please note that a visa itself does not allow you to work in Denmark unless the Immigration Service has explicitly granted you this right.
During visits of less than 90 days you may carry out certain work-related activities without holding a work permit.