BOS (Boston) to SFO (San Francisco) flights arrive on time 77% of the time. The most reliable airline on this route is United Airlines at 80%. The average delay is 64 minutes. Delays on this route are most often caused by the incoming plane arriving late.
Source: Bureau of Transportation Statistics. Updated April 2026.BOS → SFO
BOS (Boston) to SFO (San Francisco)
BOS → SFO on-time performance by month
24
25
JanFebMarAprMayJunJulAugSepOctNovDec
Worse
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This route is on time most of the time. About 77% of flights arrive on schedule.
Delays on this route are most often caused by the incoming plane arriving late.
Accurate?
United Airlines edges out Alaska Airlines on this route — 80% vs 70% on time.
Airline Comparison
United Airlines leads at 80% on time; Alaska Airlines trails at 70%.
Accurate?
Good to know
Departing from BOS
79% on timeExpect ~19 min sitting on the taxiway after your gate pushes back. BOS has long runway queues.
TSA is currently ~5 min. Best time: 4 AM (about 5 min).
Arriving at SFO
80% on timeWhen flights into SFO are late, the average delay is 67 minutes. Build buffer if you have ground plans.
If connecting at SFO: TSA is ~5 min right now. Allow at least 60 minutes for a domestic connection.
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Data last updated April 2026. Source: Bureau of Transportation Statistics.