Seattle to St. Louis (SEA-STL): nonstop upgrade & award space

Alaska Airlines flies the SEA to STL nonstop about 12 times a week. In the timetable below it flies as AS 618 and AS 647, scheduled at 3h 56m to 4h 4m for the 1,705 miles. 2LNR checks confirmed upgrade and award space on Alaska Airlines flights on this route, so you can see which departures have space before you book.

Schedule last confirmed . Departure times come from 2LNR's schedule data; confirm with the airline before you book.

Updated .

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12
Flights a week, 4-week average
3h 56m to 4h 4m
Scheduled flight time
1,705 mi
Nonstop distance
Free
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Seattle to St. Louis flight schedule

Scheduled nonstop departures for SEA to STL starting October 23, 2026, last checked against our schedule feed on October 18, 2026. Airlines retime and cancel flights, so confirm with the airline before you book.

Schedule data dated .

Scheduled nonstop departures from Seattle (SEA) to St. Louis (STL)
Date Flight Airline Departs SEA Arrives STL Duration Aircraft
AS 647Alaska Airlines, Inc.09:4015:444h 4mBoeing 737 MAX 9
AS 618Alaska Airlines, Inc.18:0323:593h 56mBoeing 737 MAX 9
AS 647Alaska Airlines, Inc.09:4015:444h 4mBoeing 737 MAX 9
AS 618Alaska Airlines, Inc.18:0323:593h 56mBoeing 737 MAX 9
AS 647Alaska Airlines, Inc.09:4015:444h 4mBoeing 737 MAX 9
AS 618Alaska Airlines, Inc.18:0323:593h 56mBoeing 737-800
AS 647Alaska Airlines, Inc.09:4015:444h 4mBoeing 737-800
AS 618Alaska Airlines, Inc.18:0323:593h 56mBoeing 737-900
AS 647Alaska Airlines, Inc.09:4015:444h 4mBoeing 737-900
AS 618Alaska Airlines, Inc.18:0323:593h 56mBoeing 737-800
AS 647Alaska Airlines, Inc.09:4015:444h 4mBoeing 737-900
AS 618Alaska Airlines, Inc.18:0323:593h 56mBoeing 737-800
AS 647Alaska Airlines, Inc.09:4015:444h 4mBoeing 737-900
AS 618Alaska Airlines, Inc.18:0323:593h 56mBoeing 737-800

Showing all 14 scheduled SEA to STL departures across 7 days with service, starting October 23, 2026. Later dates are on the interactive map.

Departure and arrival times are local at their own airport, so an arrival can fall on a different local date than the departure; the duration column is the true elapsed flying time. A dash means the airline hasn't filed that value in the schedule data we hold. Aircraft are the equipment the airline filed, named where the code pins down one type and shown as the family or the bare code where it doesn't. Swaps can happen up to departure.

See every SEA to STL date on the interactive map

Aircraft on the Seattle to St. Louis nonstop

Alaska Airlines flies the departures in the schedule table on this page with the Boeing 737 MAX 9, the Boeing 737-800, and the Boeing 737-900. Each linked aircraft page shows where that airline schedules it. Airlines can swap aircraft up to departure.

Confirmed upgrade & award space on SEA to STL departures

2LNR tracks confirmed upgrade and award space on Alaska Airlines, segment by segment and date by date. Open the calendar for Seattle to St. Louis to see which departures have space, the next 14 days free on every product and the full horizon on Pro.

Alaska Airlines award space was open on 7 of the 14 Seattle to St. Louis departure dates from October 19 to November 1 that 2LNR checked in the 7 days to October 19, 2026.

See real availability

Confirmed upgrade or award seats by date on the SEA to STL departures 2LNR tracks, checked against live inventory so you know what's open before you book.

Set an alert

Premium inventory turns over fast. Watch this route on Pro and 2LNR notifies you when space appears on a date you're tracking.

Plan on the map

See SEA to STL on the interactive route map, with schedules, connections, and route statistics.

Airlines flying Seattle to St. Louis nonstop

Carriers operating SEA to STL nonstop in the current schedule. Where 2LNR tracks the carrier, its departures show confirmed upgrade or award space by date.

See SEA to STL on the interactive map →

Frequently asked questions about SEA to STL

How long is the flight from Seattle (SEA) to St. Louis (STL)?
Scheduled flight times from Seattle (SEA) to St. Louis (STL) run from 3h 56m to 4h 4m across the departures in the schedule table on this page. The nonstop covers about 1,705 miles, and airlines adjust scheduled times by season, so confirm with the airline before you book.
Which airlines fly nonstop from SEA to STL?
Alaska Airlines is currently the only airline flying SEA to STL nonstop. 2LNR tracks confirmed upgrade and award space on Alaska Airlines.
How many flights a week are there from SEA to STL?
About 12 nonstop flights a week run between Seattle (SEA) and St. Louis (STL) in the current schedule, operated by Alaska Airlines. Frequency shifts by season, and the schedule table on this page shows what is scheduled next.
What time do flights from SEA to STL depart?
Scheduled SEA to STL nonstops in the next 7 days with service leave between 09:40 and 18:03, local time at Seattle. The schedule table on this page lists every departure by date, with its arrival time and aircraft.
Which flights operate SEA to STL nonstop?
In the schedule table on this page, SEA to STL nonstops fly as AS 618 and AS 647 on Alaska Airlines. The table lists each departure by date with its times and aircraft.
How do I check upgrade or award availability on SEA to STL?
Open the SEA to STL route on the interactive map or the matrix to see confirmed upgrade and award space by date on Alaska Airlines, the next 14 days free and the full horizon on Pro. On Pro you can also set an alert on the route and 2LNR notifies you when space opens.

Never miss SEA to STL upgrade or award space

See what's open by date on this route, the next 14 days free on every product and the full horizon on Pro.

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