A person can acquire Finnish citizenship on the basis of
1) birth. A child acquires Finnish citizenship automatically if the mother is a Finnish citizen. Also, if the child's father is a Finnish citizen and the parent's are married a child acquires citizenship (legitimation). Child's birth should be registered in The Finnish Population Register Center.
2) declaration. If the child's parents are not married, the child of a Finnish father can acquire Finnish citizenship via the declaration process as long as the paternity has been confirmed according to the Finnish law. Since February 2010 if the child has been born in the UK and the birth certificate includes father's details, paternatiny should be confirmed in Finland automatically. There is a fee for declaration.
More information from the Finnish Immigration Service.
3) place of birth. A child acquires Finnish citizenship based on the place of birth if the child is born in Finland and cannot acquire any other citizenship.
4) application. A foreigner may acquire Finnish citizenship upon application if certain requirements are reliably established. Application can be submitted only in Finland. There is a fee for application.
There are other grounds, such as adoption, for acquiring Finnish citizenship as well. For more information and fees kindly contact the Finnish Immigration Service or the Consular section.
A new Finnish Nationality Act permitting dual (and multiple) nationality more broadly than before came into force on June 1, 2003.
A Finn does not forfeit Finnish citizenship on gaining citizenship of another country. Similarly, foreigners who gain Finnish citizenship no longer need to give up their earlier citizenship.
A Finn may keep Finnish citizenship if dual nationality is accepted in the country whose citizenship he or she gains. Likewise, foreigners can keep their earlier citizenship if the law in that country does not prevent them from gaining Finnish citizenship too.
A child can gain dual nationality at birth if the parents are married but have different citizenships. If a child has dual citizenship by birth, this should be informed when registering the birth.
Kindly note that it is person's own responsibility to update their citizenship information in the Population Register.
In order for other citizenships to be entered in the Population Register in Finland, the original citizenship decision with legalisation (or certified copies) must be submitted to the nearest Finnish Embassy or register office in Finland. The decision must be either in Finnish, Swedish or English.
A person born and resident abroad who has dual nationality (Finland and another country) may have to forfeit Finnish citizenship on reaching the age of 22.
A Finnish citizen who is also a citizen of a foreign country can keep Finnish citizenship only if he or she has a sufficiently strong link with Finland. What this means is defined in the Finnish Citizenship Act.
A sufficiently strong link is considered to exist if one of the following criteria is fulfilled:
1) if you were born in Finland and are domiciled in Finland when turning 22,
2) if you have lived in Finland, or another Nordic country (Iceland, Norway, Sweden or Denmark) for a total of seven years before reaching the age of 22,
3) if you were issued a Finnish passport at the age18-21,
4) if you at the age 18-21 have stated in writing to a Finnish diplomatic mission abroad or to a Finnish local registry office, that you wish to retain Finnish citizenship. The declaration is free-form and can be submitted either in person or by post.
5) if you have done military or non-military service at the age 18-21.
A person with dual nationality and resident outside Finland may apply for an exemption from Finnish military service.
Exemption can be done in the following cases:
1) a person has completed military service in another country,
2) a person has lived abroad at least seven years,
3) a person cannot prove to have ties to Finland.
Above mentioned circumstanses should be proven with a free-form letter addressed to the Military Province Headquarters in the military province where the person’s municipality of residence is located.
More information: The Finnish Defence Forces
Please note that dual nationals should keep their Finnish Population Register data up-to-date regarding citizenships and address.
Amendments to the Nationality Act (Kansalaisuuslaki 359/2003) entered into force as of 1 September 2011.
The Nationality Act includes also amendments that concern persons living abroad.
Former Finnish citizens can re- apply for citizenship by declaration. The citizenship will be granted regardless of whether the former Finnish citizen’s domicile is in Finland or abroad.
The declaration procedure does not apply to Finnish citizens’ children.
A person living abroad (former Finnish citizen, illegitimate children of Finnish men, adopted children) can submit a declaration at any police station in Finland or at the relevant Finnish representation. The declaration can also be filed at the nearest embassy.
A child’s parent or legal guardian or representative can submit a declaration on behalf of the child.
Retaining Finnish citizenship at the age of 22 has also changed. As of 1 September 2011, applying for a Finnish passport at the age of 18-21 years serves as proof of sufficiently close ties to Finland. Furthermore, starting military or non-military service or voluntary military service for women before turning 22 years of age will prevent losing Finnish citizenship. Those who have acquired Finnish citizenship by application or by declaration will retain their citizenship at the age of 22.
More information about the amended Nationality Act and the fees are available on the home page of the Finnish Immigration Service