If you are a Swedish, Danish, Icelandic or Finnish citizen, all you need to do to live in Norway, is to report a move to the National Registry.
A Nordic citizen is defined as a person with Danish, Finnish, Icelandic, Norwegian or Norwegian citizenship. This also include the Faroe Islands and Greenland (Danish citizenship) and Åland (Finnish citizenship).
If you plan to live in Norway for more than six months, you must visit a Tax Administration office for ID verification and to submit a change of address notification (external website) no later than eight days after you arrive in Norway. You have to book an appointment at a tax office. Nordic citizens are not issued a registration certificate.