Altius recorded 145 priced readings of nonstop business-class round trips from Boston (BOS) to San Diego (SAN) booked 90 days out, across 73 departure dates between 2026-07-25 and 2026-10-05. Observed fares ran from US$937 to US$2,431. The lowest fare Altius scored on this window was US$937 for a 2026-12-08 departure, seen on 2026-09-09 — RARE at the time, 33.7% below the US$1,413 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.