SEA → STLSeattle to St Louis

live

Direct flights from Seattle (SEA) to St Louis (STL): 11 nonstop departures observed each week across 2 airlines. The median arrival is 29 minutes early. No cancellations were recorded across the 3 tracked flights. The nonstop covers 2,744 km, an estimated 4 hours 1 minutes in the air. Measured by Pro Flight Search from live flight boards at Seattle and St Louis. Updated 16 September 2026 at 16:30 UTC.

SEA Seattle smooth · +14
STL St Louis smooth · +0
2,744 km · ~4h 01m est.
dep bank 08:13–18:0311x weekly
Running clean · 2 airlines · 11x weekly · nonstop
91 / 100

route health from live SEA and STL delay boards

Median arrival delay is −29 min. 0 of 3 tracked legs cancelled in the sample. Will a delayed flight be cancelled? →

Median arrival−29 minacross the last 3 operated legs
Flight time~4h 01mestimated from route distance
Weekly departures11x2 direct airlines on the leg

The week

scheduled departures · origin local time
06121824
Mon
Tue
Wed
Thu
Fri
Sat
Sun
Alaska AirlinesSouthwest 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 days
Alaska AirlinesAS

Flights AS388 08:13 daily · AS672 12:35 daily · AS472 18:03 Mo Th Fr Su

Southwest AirlinesWN

Flights WN3149 09:40 Sa · WN2631 12:05 Mo Th Fr

History

operated legs · board outcomes
09-16AS388arrived−46
09-15AS388arrived−29
09-15AS672arrived−25

Actual board outcomes rather than schedules, paired departure and arrival per flight and day.

Full board history, day by day →

Airports right now

live boards
SEASeattle +14 min smooth 🌤 few clouds · NNE 10 kt Full SEA delay board →
STLSt Louis +0 min smooth 🌤 mostly cloudy · E 6 kt Full STL delay board →

Weather lens

Current conditions put the pressure at STL: 40% odds of a 15+ minute delay and around +9 min expected when it bites, measured from this route's own weather-matched delay history. See live delays → · Weather risk by airport →

How the Seattle to St Louis route actually runs

Pro Flight Search records official board updates for nonstop SEA to STL 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 — Seattle (SEA) to St Louis (STL) route reliability, measured from operated flights on official airport boards.

Canonical URL
https://proflightsearch.com/search-flights/SEA-STL
How we measure this →

SEA to STL questions

Is SEA–STL running on time right now?

Smooth skies ahead. The departure side at SEA is the weaker end, route health score 91/100. The airports section above carries the live status and delay window at both ends.

Morning or evening flight on SEA–STL?

Operators schedule morning departures around 08:13 and evening departures around 18:03 from SEA. Earlier flights typically land before destination-airport delays accumulate later in the day; check the STL delay card to confirm conditions when you'd arrive.

How long is the flight from SEA to STL?

Great-circle distance is 2,744 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 SEA–STL fly?

2 carriers operate this route, around 22 flights a week between them. Compare carrier days and times in the airline list above.