Altius recorded 250 priced readings of nonstop business-class round trips from London (LHR) to Boston (BOS) booked 30 days out, across 121 departure dates between 2026-06-06 and 2026-10-05. Observed fares ran from US$3,544 to US$13,105. The lowest fare Altius scored on this window was US$4,588 for a 2026-11-04 departure, seen on 2026-10-05 — DECENT at the time, 10.8% below the US$5,143 this route was typically running that day.
A fare can move between our two readings of the same day, most often on the days furthest below typical. Where a day's two readings differ enough to matter, the chart marks that day and both readings can be read separately.