Right to vote
Regardless of domicile, every Finnish citizen who has reached the age of 18 not later than on the day of the election is entitled to vote.

Voting register
The Population Register Centre compiles a computer register of everyone entitled to vote (voting register) at the latest 46 days before election day. This registers contains some of the information on the voters (e.g. name, personal number, electoral district, municipality of residence, and polling station) which was in the Population Information System 51 days before election day.

The voting register is public and the local register offices (maistraatti) give out information from the register by phone or as extracts (if the extract is given to someone else than the voter a fee is charged for the extract) from day 41 before election day. In addition, everyone in the register is sent a notice of his or her right to vote (card of information) not later than 24 days before election day. The card states among other things the election day, the days for advance voting, a list of the advance polling stations within the electoral district, the name and address of the polling station on election day, and the addresses and telephone numbers of the election authorities. The voting register is later used to print out electoral rolls for the polling stations on election day.

Claims for correction
Claims for correction of the register must be submitted to the local register office not later than 16 days before election day. A correction may be demanded e.g. if somebody considers that he or she has without cause been left out of the register or that the information in the register is incorrect. The local register office must decide the claims not later than 13 days before election day.

A person not satisfied with a decision may appeal against it to a regional administrative court within seven days of service. The decision of the regional administrative court is not subject to appeal. An appeal to the Supreme Administrative Court is, however, possible in accordance with so-called extraordinary rights of appeal, i.e. an extraordinary appeal or application for the annulment of the administrative decision or for the restoration of lapsed time may be submitted. These are nevertheless extremely rare.

Validity of the voting register
The voting register becomes legally valid at noon 12 days before election day. After this it may not be amended, i.e. a person may neither be erased from nor added to the register and the information may not be changed. The only exceptions to this are the cases in which a regional administrative court or the Supreme Administrative Court reaches its decision after the register has already become legally valid. Then persons who e.g. pursuant to the court decision have been added to the voting register may vote in the elections, but they have to take the decision with them to the polling station and present it to the election authorities.