This is the country-code top level domain from Finland.
You can check Domain availability here.
The Terms and Conditions can be found here.
IDN is supported (Special characters like å, ä, ö, more info here).
Blocked and not-allowed domains here.
When .FI domains are registered through us, we will require an identification number the same that will be sent along with the domain registration request. This number may vary depending on your current situation:
If you are an individual located in Finland a valid Finnish Identity Number is required.
If you are registering this domain under a Finnish Organization, an Official Organization Number is required.
For individuals outside Finland, the personal date of birth is required.