As an EU citizen, you need to register your right of residence if you stay in Finland for longer than 90 days
If you are a citizen of an EU Member State, Liechtenstein or Switzerland, you do not need a residence permit to stay in Finland. However, you need to register your right of residence if you stay in Finland for longer than 90 days. Read more on the page Registration of right of residence.
You should also register your right of residence if you are a family member of an EU citizen and also an EU citizen yourself.
The Member States of the European Union (EU) are Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Poland, Portugal, Romania, Slovakia, Slovenia, Spain and Sweden.