Flights St. Louis → Seattle
STL → SEA
How long is the flight from St. Louis to Seattle?
The flight from St. Louis (STL) to Seattle (SEA) takes 3h 52m on average. That is the median time recorded across 3 scheduled flights on this leg; the actual time varies by a few minutes with wind, routing and take-off queues.
Route overview
The flight route from St. Louis to Seattle operates with a high on-time performance rate of 92%, with an average delay of just 5.1 minutes. Over the course of a year, this route sees approximately 150 flights using Boeing 737 aircraft, serving a destination airport that handles nearly 52.7 million passengers annually.
Your rights on this US flight (DOT)
US flights have no statutory cash compensation for delays. Under the US DOT rules, if your flight is cancelled or significantly changed and you decline rebooking, you're owed an automatic refund of the unused ticket. The tarmac-delay limit is 3 hours (domestic) / 4 hours (international). Amenities for controllable delays depend on each airline's contract of carriage.
US flight refund rules & checker →General information, not legal advice.
The St. Louis (STL) → Seattle (SEA) route is operated by American Airlines, Alaska Airlines. Across 546 flights monitored in recent months, 83% arrived on time (within 15 min of schedule), with an average delay of 8 minutes. The cancellation rate is 1.83%. FlightGuard's average computed risk is 22.2/100 (medium), updated in real time from weather, ATC delays, strikes, NOTAMs, fuel and flight history. At Seattle the average ATFM delay is 5.5 minutes (main cause: atfm). Departing from St. Louis the average ATFM delay is 5.5 minutes.
Heading to Seattle: what to expect in this direction
Flying from St. Louis (STL) to Seattle (SEA) heads north-west for about 2,744 km, a flight time of roughly 3h 52m.
Departures from St. Louis on this leg cluster in the morning window: about 51% of STL-SEA flights take off then.
Air-traffic congestion: departing St. Louis the average ATFM delay is 5.5 min (atfm); arriving into Seattle it is 5.5 min (atfm).
Across 546 tracked STL-SEA flights, 83% left on time with an average delay of 8 min and a 1.8% cancellation rate.
Route facts
Flights on this route
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Airline punctuality on this route
| Airline | On-time | Average delay | Cancellations |
|---|---|---|---|
| Alaska Airlines (AS) | 85% | -1 min | 0.5% |
| American Airlines (AA) | 79% | 6 min | 1.1% |
Airlines operating STL-SEA
Airports
Frequently asked questions about STL-SEA
The flight from St. Louis (STL) to Seattle (SEA) takes 3h 52m on average. That is the median time recorded across 3 scheduled flights on this leg; the actual time varies by a few minutes with wind, routing and take-off queues.
On the St. Louis (STL) -> Seattle (SEA) route, on-time performance is 83% with an average delay of 8 minutes, based on 546 tracked flights.
The cancellation rate on St. Louis-Seattle is 1.83% across 546 monitored flights.
The route is operated by 2 airlines: American Airlines, Alaska Airlines.
Enter your flight number on FlightGuard for a real-time analysis based on 9 factors: weather at Seattle, ATC delays, strikes, NOTAMs, fuel, airline punctuality and recent trends.
US flights have no statutory cash compensation for delays. Under US DOT rules, if the airline cancels or significantly changes your flight and you decline rebooking, you're owed an automatic refund of the unused ticket. The tarmac-delay limit is 3 hours (domestic) / 4 hours (international). Meals or hotels for controllable delays depend on each airline's contract of carriage.
