Logan International (BOS) to San Francisco International (SFO).
| Departure | Return | Price |
|---|---|---|
| 07/22/2026 | 07/28/2026 | $254 |
| 06/10/2026 | 06/16/2026 | $264 |
| 06/10/2026 | 06/17/2026 | $264 |
| 07/22/2026 | 07/29/2026 | $264 |
| 06/10/2026 | 06/19/2026 | $269 |
| 07/22/2026 | 07/27/2026 | $269 |
| 05/28/2026 | 06/02/2026 | $274 |
| 05/28/2026 | 06/06/2026 | $274 |
| 05/29/2026 | 06/06/2026 | $274 |
| 05/30/2026 | 06/06/2026 | $274 |
Based on current fares, July is the cheapest month to fly from Boston to San Francisco, with average fares around $306 round trip (as low as $254).
See the full month-by-month and day-of-week price analysis
Best Time to Fly BOS → SFODeparture date prices (economy, round trip). Green = cheap, red = expensive.
The cheapest month to fly from Boston to San Francisco is July, with average round-trip fares around $306. Fares in July start as low as $254. The most expensive month is June, averaging $330.
A nonstop flight from Boston to San Francisco takes approximately 6h.
The cheapest flight from Boston to San Francisco currently starts at $254 round trip in economy class.
The average round-trip flight price from Boston to San Francisco is $337 in economy class.
The distance is 2704 miles (4351 km). with a nonstop flight time of about 6h. The lowest fare currently available is $254 departing in July. The average round-trip fare is $337.
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