Seattle (SEA) to Saint Louis (STL) flights
2 airlines fly nonstop from Seattle (SEA) to Saint Louis (STL): Alaska Airlines and Southwest Airlines. The two airports are 1,704 miles (2,743 km) apart. Alaska Airlines is in oneworld. There are also 41 ways to fly it with one stop, through Omaha, Kansas City and Denver and more.
Airlines flying nonstop from SEA to STL
- Alaska Airlinesoneworld · bookable with 9 programsWho books it

- Southwest AirlinesNot in an allianceWho books it

Book SEA to STL with points
Loyalty programs that can book at least one of the nonstop airlines, from the Award Booking Guide.
- Alaska Atmos RewardsBooks Alaska Airlines
- American AAdvantageBooks Alaska Airlines
- British Airways ClubBooks Alaska Airlines
- Cathay Pacific Asia MilesBooks Alaska Airlines
- Finnair PlusBooks Alaska Airlines
- Iberia ClubBooks Alaska Airlines
- JAL Mileage BankBooks Alaska Airlines
- Qantas Frequent FlyerBooks Alaska Airlines
- Qatar Airways Privilege ClubBooks Alaska Airlines
SEA to STL with one stop
41 connections, most direct first. 2-stop routings and flight times are in Routes with Pro.
- Via Omaha (OMA)Alaska Airlines, then Southwest Airlines


- Via Kansas City (MCI)Southwest Airlines the whole way




- Via Denver (DEN)Frontier Airlines, United Airlines and 1 more the whole way

+3



- Via Portland (PDX)Alaska Airlines the whole way




- Via Salt Lake City (SLC)Delta Air Lines the whole way



- Via Minneapolis (MSP)Delta Air Lines the whole way





- Via Chicago (ORD)American Airlines and United Airlines the whole way

+1


- Via Chicago (MDW)Southwest Airlines the whole way


- Via Milwaukee (MKE)Alaska Airlines, then Southwest Airlines


- Via Dallas (DFW)American Airlines the whole way





- Via Dallas (DAL)Southwest Airlines the whole way


- Via Las Vegas (LAS)Southwest Airlines and Frontier Airlines the whole way

+2


- Via Nashville (BNA)Southwest Airlines the whole way




- Via Sacramento (SMF)Southwest Airlines the whole way




- Via Phoenix (PHX)American Airlines and Southwest Airlines the whole way

+1


SEA to STL: common questions
Which airlines fly nonstop from SEA to STL?
Alaska Airlines (oneworld) and Southwest Airlines fly nonstop from Seattle (SEA) to Saint Louis (STL).
How far is Seattle from Saint Louis by plane?
Seattle (SEA) and Saint Louis (STL) are 1,704 miles (2,743 km) apart along the great circle, the shortest path a flight can take. Connections add distance on top.
Which points programs can book SEA to STL award flights?
9 programs can book at least one of the nonstop airlines: Alaska Atmos Rewards, American AAdvantage, British Airways Club, Cathay Pacific Asia Miles, Finnair Plus, Iberia Club, JAL Mileage Bank, Qantas Frequent Flyer and 1 more. Which flights each can book depends on its partners, so check the airline before you transfer points.
How many miles does SEA to STL cost?
It depends on the program: each prices the route from its own chart or dynamically. The Award Flight Pricer compares 30+ programs for SEA to STL with taxes and fees.
Where can I connect between Seattle and Saint Louis?
The most direct connections are through Omaha (OMA), Kansas City (MCI), Denver (DEN), Portland (PDX) and Salt Lake City (SLC). On 28 of them the same airline flies both flights, for example Southwest Airlines through Kansas City.
More routes
Routes are scheduled nonstop flights. The route data is refreshed monthly; this list was last checked November 11, 2026. Seasonal routes and new launches can be missing or end early, so confirm with the airline before you book. Distances are great-circle, the shortest path between the two airports.