The cheapest Luxembourg to Boston return flight on the radar right now is €433, flying with TAP Air Portugal via one or more connections. It covers departures in November 2026, and every dated link below opens that exact LUX–BOS search on Skyscanner. That is roughly 17% below the €522 this route usually costs. Across 99 recorded checks it has ranged between €307 and €900. Our sampling points to November 2026 as the cheapest month to fly Luxembourg 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 Luxembourg? 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 Luxembourg to Boston is often still worth booking within a day or two of the fare we found.