SEA (Seattle) to SLC (Salt Lake City) flights arrive on time 84% of the time. The most reliable airline on this route is Delta Air Lines at 89%. The average delay is 51 minutes. Delays on this route are most often caused by the airline (crew, maintenance, or boarding).
Source: Bureau of Transportation Statistics. Updated April 2026.SEA → SLC
SEA (Seattle) to SLC (Salt Lake City)
SEA → SLC on-time performance by month
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JanFebMarAprMayJunJulAugSepOctNovDec
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This route is on time most of the time. About 84% of flights arrive on schedule.
Delays on this route are most often caused by the airline (crew, maintenance, or boarding).
Accurate?
Delta Air Lines edges out Alaska Airlines on this route — 89% vs 78% on time.
Airline Comparison
Delta Air Lines leads at 89% on time; Alaska Airlines trails at 78%.
Accurate?
Good to know
Departing from SEA
82% on timeExpect ~19 min sitting on the taxiway after your gate pushes back. SEA has long runway queues.
TSA is currently ~15 min. Best time: 4 AM (about 5 min).
Arriving at SLC
85% on timeWhen flights into SLC are late, the average delay is 70 minutes. Build buffer if you have ground plans.
If connecting at SLC: TSA is ~6 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.