Southwest AirlinesWN
Flights WN2190 08:48 Fr
live
Direct flights from St Louis (STL) to Seattle (BFI): 1 nonstop departure observed each week across 1 airline. The nonstop covers 2,745 km, an estimated 4 hours 1 minutes in the air. Measured by Pro Flight Search from live flight boards at St Louis and Seattle. Updated 12 September 2026 at 08:58 UTC.
STL
St Louis
heavy · +33
BFI
Seattle
tracking
2,745 km · ~4h 01m est.
Under pressure · 1 airline · 1x weekly · nonstop
56 / 100
route health from live STL and BFI delay boards
Flight time~4h 01mestimated from route distance
Weekly departures1x1 direct airline on the leg
The week
scheduled departures · origin local time06121824
Mon
Tue
Wed
Thu
Fri
Sat
Sun
Southwest Airlines
Each mark is a scheduled departure at its origin-local time, observed operating in the last 7 days. Today is highlighted.
Who flies it
observed on the boards · 7 daysAirports right now
live boardsnext sweep in 120s
How the St Louis to Seattle route actually runs
Pro Flight Search records official board updates for nonstop STL to BFI flights through the day: schedules, estimates, gate pushes and actual departures. The verdict above comes from operated flights, so it reflects what this route does rather than what the timetable promises.
Planning around a delay? Live airport delays · Weather delay risk map · Will a delayed flight be cancelled? · Do planes make up time in the air? · How we measure
Cite this data
Journalists, bloggers, and researchers may cite this page with attribution and a link to Pro Flight Search.
Suggested citation
Pro Flight Search — St Louis (STL) to Seattle (BFI) route reliability, measured from operated flights on official airport boards.
Canonical URL
How we measure this →
https://proflightsearch.com/search-flights/STL-BFI
STL to BFI questions
Is STL–BFI running on time right now?
Some delays possible. The departure side at STL is the weaker end, route health score 56/100. The airports section above carries the live status and delay window at both ends.
How long is the flight from STL to BFI?
Great-circle distance is 2,745 km. With typical jet cruise speed plus taxi, climb and descent, expect roughly 224–265 min gate-to-gate on this route.
How often does STL–BFI fly?
Southwest Airlines runs the route with about 1 flight a week (fri). Since one carrier owns the route, a single disruption tends to ripple through the day.
What does the route health score measure?
A blend of departure-side delay at STL and arrival-side delay at BFI, computed from rolling delay windows (refreshed every 40 minutes) with a daily-rollup fallback. Current MVFR, IFR, or LIFR endpoint weather caps the score when flight rules can limit throughput. Higher is healthier: 100 means operations are clean at both ends.
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