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SEASFO

SEA (Seattle) to SFO (San Francisco)

SEA (Seattle) to SFO (San Francisco) flights arrive on time 77% of the time. The most reliable airline on this route is Southwest Airlines at 81%. The average delay is 39 minutes. Delays on this route are most often caused by the airline (crew, maintenance, or boarding).

Source: Bureau of Transportation Statistics. Updated March 2026.

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SEA → SFO on-time performance by month

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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 airline (crew, maintenance, or boarding).

Airlines are roughly equal on this route — Southwest Airlines leads slightly at 81% vs United Airlines at 78%.

Airline Comparison

Southwest Airlines leads at 81% on time; United Airlines trails at 78%.

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Data last updated March 2026. Source: Bureau of Transportation Statistics.