The cheapest Dublin to Boston return flight on the radar right now is €451, flying with Icelandair via one or more connections. It covers departures in December 2026, and every dated link below opens that exact DUB–BOS search on Skyscanner. The price we usually record on this route is €431. Across 124 recorded checks it has ranged between €163 and €669. Our sampling points to December 2026 as the cheapest month to fly Dublin to Boston.
Prices are re-checked against Skyscanner automatically, and every one shows when it was last confirmed, so nothing here is older than it looks. Not flying from Dublin? We track 53 other departure cities for Boston, listed at the foot of this page.
Prices like this tend to vanish fast. If it has gone when you look, try the days either side of the dates above, since Dublin to Boston is often still worth booking within a day or two of the fare we found.