The cheapest round-trip from Helsinki to San Francisco is about 729 EUR, usually in September 2026; July 2026 is priciest, so booking the low month saves around 120 EUR (~14%). Typical fare ~746 EUR, from 152 priced fares. Flightmussy live data, updated 2026-06-13.
Cheap flights from Helsinki (HEL) to San Francisco (SFO/OAK/SJC). Free, no signup, no ads, no tracking. Compare every airline across 12 months of fares on one heatmap — including low-cost carriers Google Flights often deprioritises.
Cheapest round-trip seen: 729 EUR, usually around September 2026. Typical fare ~746 EUR. Across the year prices range roughly 729–849 EUR — about 14% cheaper in the low season than the peak (July 2026). Carriers on this route include Scandinavian Airlines, Turkish Airlines, Lufthansa, KLM.
Based on Flightmussy's live 12-month fare data; prices last updated 2026-06-13. Prices change constantly — search live for current fares.
The lowest round-trip fare we found for each month over the coming year — low season versus peak at a glance. September 2026 is cheapest; July 2026 is priciest.
| Jun 2026 | 838 EUR | |
|---|---|---|
| Jul 2026 | 849 EUR | |
| Aug 2026 | 764 EUR | |
| Sep 2026 | 729 EUR | |
| Oct 2026 | 729 EUR | |
| Nov 2026 | 729 EUR |
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