Finnish citizenship is granted by the Finnish Immigration Service on application or by declaration.
Under the current Citizenship Act which entered into force in 2003, a child of a Finnish citizen acquires Finnish citizenship at birth by virtue of law. (This is called the parentage principle.) However, Finnish citizenship is not automatically transferred to a child born abroad and out of wedlock to a Finnish father or to a child born abroad to a Finnish non-birth mother. The parentage principle is applied in accordance with the provisions of the Citizenship Act that were in force at the time the child was born.
A child can acquire Finnish citizenship on the basis of his or her parents’ marriage if the father was a Finnish citizen at the time of the child’s birth and has been a Finnish citizen ever since. If, however, paternity is established after the contraction of the marriage and the father is still a Finnish citizen, the child may acquire Finnish citizenship only as of the date on which paternity is established.
In some rare cases, a child may obtain Finnish citizenship on the basis of being born in Finland if the child would otherwise remain stateless.
