Henkilöllisyystunnus

Henkilöllisyystunnus, often abbreviated as HETU, is the Finnish personal identity code. It is a unique alphanumeric identifier assigned to all individuals residing in Finland and those with a Finnish connection, such as Finnish citizens living abroad. The primary purpose of the henkilöllisyystunnus is to enable unambiguous identification of individuals in various administrative and legal contexts.

The structure of the henkilöllisyystunnus consists of personal identification numbers and a check digit. The personal identification number is formed by the date of birth, which is presented in the format DDMMYY. For example, someone born on January 15, 1990, would have their date of birth represented as 150190. Following the date of birth, there is a separator, typically a hyphen, and then a unique three-digit number. This three-digit number distinguishes individuals born on the same day.

Finally, the henkilöllisyystunnus concludes with a single check character, which is a letter. This check character is derived from the personal identification number using a specific algorithm. The check character serves as a safeguard against errors and ensures the validity of the henkilöllisyystunnus. The henkilöllisyystunnus is used extensively by Finnish authorities, such as the Population Register Centre, the Tax Administration, and Kela (The Social Insurance Institution of Finland), for managing social security, taxation, and other public services. It is also used by many private sector organizations for customer identification and record-keeping.