Altius recorded 144 priced readings of nonstop business-class round trips from San Francisco (SFO) to Boston (BOS) booked 90 days out, across 72 departure dates between 2026-07-25 and 2026-10-04. Observed fares ran from US$1,263 to US$13,479. The lowest fare Altius scored on this window was US$1,263 for a 2026-12-15 departure, seen on 2026-09-16 — IMPRESSIVE at the time, 24.5% below the US$1,673 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.