Altius recorded 174 priced readings of nonstop business-class round trips from London (LHR) to Sofia (SOF) booked 30 days out, across 86 departure dates between 2026-06-06 and 2026-10-03. Observed fares ran from US$604 to US$2,099. The lowest fare Altius scored on this window was US$604 for a 2026-10-28 departure, seen on 2026-09-28 — LEGENDARY at the time, 46.9% below the US$1,137 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.