Search low cost and promo Finnair flight tickets here. Passengers will modify the flight date prior to the date of your booking. you'll be able to create changes to your flight booking seventy-two hours before the departure on Finnair from its website or by visiting the landing field counter. Finnair Airlines' modification policy happens to permit you to alter your flight's date, time, or destination. Finnair change flight date policy permits passengers to form modifications for complimentary as long as the meant departure date is a minimum of days prior.