Callsign FIN is Finnair
WHAT AIRLINE IS FIN?
FIN is the ICAO three-letter callsign prefix for Finnair. When a radio scanner, flight tracker or radar scope shows a flight like FIN123 or FIN45XY overhead, that's a Finnair aircraft talking to air traffic control.
Spot one yourself: open the live scope, enter your postcode, and tap any blip whose callsign starts with FIN for its type, registration, route and photo.