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

Alaska Airlines flies nonstop between St. Louis (STL) and Seattle (SEA), roughly 19 times a week. With Alaska Airlines running most of the schedule, the shape of a week is predictable, which makes an open premium seat on a given date easy to spot and quick to lose. 2LNR tracks confirmed upgrade and award space on Alaska Airlines, on every STL to SEA departure, so you know which flights have space before you book.

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

See STL to SEA on the interactive map Get started free
19
Nonstop flights a week
1,705 mi
Nonstop distance
Free
To get started

St. Louis to Seattle flight schedule

Scheduled nonstop departures for STL to SEA, last checked against our schedule feed on September 6, 2026. Airlines retime and cancel flights, so confirm with the airline before you book.

Schedule data dated .

Scheduled nonstop departures from St. Louis (STL) to Seattle (SEA)
Date Flight Airline Departs STL Arrives SEA Duration Aircraft
AS 473Alaska Airlines, Inc.06:2908:564h 27m7M9
AS 388Alaska Airlines, Inc.15:1917:414h 22m73J
AS 473Alaska Airlines, Inc.06:2908:564h 27m7M9
AS 388Alaska Airlines, Inc.15:1917:424h 23m7M9
AS 674Alaska Airlines, Inc.19:3621:594h 23m7M9
AS 473Alaska Airlines, Inc.06:2908:564h 27m7M9
AS 388Alaska Airlines, Inc.15:1917:424h 23m7M9
AS 674Alaska Airlines, Inc.19:3621:594h 23m7M9
AS 473Alaska Airlines, Inc.06:2908:564h 27m7M9
AS 388Alaska Airlines, Inc.15:1917:424h 23m73H
AS 473Alaska Airlines, Inc.06:2908:564h 27m7M9
AS 388Alaska Airlines, Inc.15:1917:424h 23m73J
AS 674Alaska Airlines, Inc.19:3621:594h 23m73J
AS 473Alaska Airlines, Inc.06:2908:564h 27m7M9
AS 388Alaska Airlines, Inc.15:1917:424h 23m7M9
AS 674Alaska Airlines, Inc.19:3621:594h 23m7M9
AS 473Alaska Airlines, Inc.06:2908:564h 27m73J
AS 388Alaska Airlines, Inc.15:1917:414h 22m737

Showing all 18 scheduled STL to SEA departures across the next 7 days with service. 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 has not filed that value in the schedule data we hold. Aircraft are IATA equipment codes as filed, and can change up to departure.

See every STL to SEA date on the interactive map

Confirmed upgrade & award space on STL to SEA departures

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

See real availability

Confirmed upgrade and award seats on each STL to SEA departure, checked against live inventory so you know what is open before you book.

Set an alert

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

Plan on the map

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

Airlines flying St. Louis to Seattle nonstop

Carriers operating STL to SEA nonstop in the current schedule. 2LNR tracks confirmed upgrade and award space on each of them.

See STL to SEA on the interactive map →

Frequently asked questions about STL to SEA

How far is Seattle from St. Louis?
STL to SEA covers about 1,705 miles nonstop. Flight times vary by aircraft and season; the schedule table on this page lists each scheduled departure with its own times.
Which airlines fly nonstop from STL to SEA?
Alaska Airlines is currently the only airline flying STL to SEA nonstop. 2LNR tracks confirmed upgrade and award space on Alaska Airlines.
How many flights a week are there from STL to SEA?
About 19 nonstop flights a week run between St. Louis and Seattle 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 STL to SEA depart?
Scheduled STL to SEA nonstops in the next 7 days with service leave between 06:29 and 19:36, local time at St. Louis. The schedule table on this page lists every departure by date, with its arrival time and aircraft.
How do I check upgrade or award availability on STL to SEA?
Open the STL to SEA 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 STL to SEA upgrade or award space

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

Get started free