SFO (San Francisco) to BOS (Boston) flights arrive on time 79% of the time. The most reliable airline on this route is Alaska Airlines at 82%. The average delay is 69 minutes. Delays on this route are most often caused by air traffic and busy airspace.
Source: Bureau of Transportation Statistics. Updated April 2026.SFO → BOS
SFO (San Francisco) to BOS (Boston)
SFO → BOS on-time performance by month
24
25
JanFebMarAprMayJunJulAugSepOctNovDec
Worse
Better
This route is on time most of the time. About 79% of flights arrive on schedule.
Delays on this route are most often caused by air traffic and busy airspace.
Accurate?
Airlines are roughly equal on this route — Alaska Airlines leads slightly at 82% vs Delta Air Lines at 78%.
Airline Comparison
Alaska Airlines leads at 82% on time; Delta Air Lines trails at 78%.
Accurate?
Good to know
Departing from SFO
80% on timeExpect ~20 min sitting on the taxiway after your gate pushes back. SFO has long runway queues.
TSA is currently ~18 min. Best time: 4 AM (about 5 min).
Arriving at BOS
79% on timeWhen flights into BOS are late, the average delay is 74 minutes. Build buffer if you have ground plans.
If connecting at BOS: TSA is ~20 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.