United States · 1,704 miles (2,743 km)

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

Book SEA to STL with points

Loyalty programs that can book at least one of the nonstop airlines, from the Award Booking Guide.

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
    Alaska Airlines logo
    Southwest Airlines logo
  • Via Kansas City (MCI)Southwest Airlines the whole way
    Alaska Airlines logo
    Southwest Airlines logo
    Delta Air Lines logo
    Southwest Airlines logo
  • Via Denver (DEN)Frontier Airlines, United Airlines and 1 more the whole way
    Alaska Airlines logo
    Delta Air Lines logo
    Frontier Airlines logo
    +3
    Frontier Airlines logo
    United Airlines logo
    Southwest Airlines logo
  • Via Portland (PDX)Alaska Airlines the whole way
    Alaska Airlines logo
    Delta Air Lines logo
    Alaska Airlines logo
    Southwest Airlines logo
  • Via Salt Lake City (SLC)Delta Air Lines the whole way
    Alaska Airlines logo
    Delta Air Lines logo
    Delta Air Lines logo
  • Via Minneapolis (MSP)Delta Air Lines the whole way
    Alaska Airlines logo
    Delta Air Lines logo
    Sun Country Airlines logo
    Delta Air Lines logo
    Southwest Airlines logo
  • Via Chicago (ORD)American Airlines and United Airlines the whole way
    American Airlines logo
    Alaska Airlines logo
    Delta Air Lines logo
    +1
    American Airlines logo
    United Airlines logo
  • Via Chicago (MDW)Southwest Airlines the whole way
    Southwest Airlines logo
    Southwest Airlines logo
  • Via Milwaukee (MKE)Alaska Airlines, then Southwest Airlines
    Alaska Airlines logo
    Southwest Airlines logo
  • Via Dallas (DFW)American Airlines the whole way
    American Airlines logo
    Alaska Airlines logo
    Delta Air Lines logo
    American Airlines logo
    Frontier Airlines logo
  • Via Dallas (DAL)Southwest Airlines the whole way
    Southwest Airlines logo
    Southwest Airlines logo
  • Via Las Vegas (LAS)Southwest Airlines and Frontier Airlines the whole way
    Alaska Airlines logo
    Delta Air Lines logo
    Southwest Airlines logo
    +2
    Frontier Airlines logo
    Southwest Airlines logo
  • Via Nashville (BNA)Southwest Airlines the whole way
    Alaska Airlines logo
    Delta Air Lines logo
    Southwest Airlines logo
    Southwest Airlines logo
  • Via Sacramento (SMF)Southwest Airlines the whole way
    Alaska Airlines logo
    Delta Air Lines logo
    Southwest Airlines logo
    Southwest Airlines logo
  • Via Phoenix (PHX)American Airlines and Southwest Airlines the whole way
    American Airlines logo
    Alaska Airlines logo
    Delta Air Lines logo
    +1
    American Airlines logo
    Southwest Airlines logo
See all 41 in Routes

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.