There are several interpretation companies operating in Finland. Interpreting services are available in a number of languages. In some situations, the authorities can order and pay for interpreting. There are several situations in which the authorities are under an obligation to obtain an interpreter or translator for the customer by law.
However, this is not always possible. You should ask the authorities about the right to receive interpreting services in advance. Even if you are not entitled to have an interpreter provided by the authorities, you can always hire an interpreter at your own expense.
Interpreting services are listed on the Info Bank’s site in 15 languages: Do you need an interpreter?