Tickets at this price are available starting in late January with returns available through early April. Departures are available Sunday through Thursday.
Connections take place in Reykjavik (KEF) where you have the option of adding a free stopover and can turn this already fantastic deal into a two-for-one!
This fare is an Icelandair "light fare" which only includes carry-on baggage, if you need to check a bag it will cost additional.
As an example, I found seats at this price departing BOS on Wednesday, March 27 and returning from HEL on Friday, April 5, 2019. Other dates are widely available during this travel window.
If Helsinki isn't for you, then take a look at all our other departures from Boston (BOS) on sale today.
Need a room in the Finnish capital? Here's what's available for the mentioned dates on Hotelwatchdog.