🇺🇸 STL
St Louis
1707 mi
SEA 🇺🇸
Seattle

St Louis to Seattle Flights

St. Louis Lambert International Airport Seattle–Tacoma International Airport 2 airlines

Get Notified About Route Changes

Track up to 3 airports free. Weekly alerts when airlines add or remove routes.

Sign Up Free

The St Louis to Seattle route connects St. Louis Lambert International Airport (STL) in US with Seattle–Tacoma International Airport (SEA) in US. This medium-haul flight covers approximately 1707 miles (2747 km) with a typical flight time of 3h 22m. This route is served by 2 airlines: Alaska Airlines, Southwest. AirportRoutes has tracked 3 unique flight numbers on this route.

Search tickets for this route

Compare flight prices across hundreds of booking sites

Search STL → SEA flights

Opens a live price search — just pick your dates

Departure Airport

St. Louis Lambert International Airport

ICAO Code:
KSTL
IATA Code:
STL
City:
🇺🇸 St Louis
Country:
US
Elevation:
618 ft

Destination Airport

Seattle–Tacoma International Airport

ICAO Code:
KSEA
IATA Code:
SEA
City:
🇺🇸 Seattle
Country:
US
Elevation:
433 ft

2

Operators

3

Tracked Flights

1707

Miles

3h 22m

Flight Duration

Route Map

Operating Airlines

Airline ICAO IATA
Alaska Airlines ASA AS
Southwest SWA WN

Flight Schedule Pattern

Day Flights Observed Frequency Activity
Monday 5 21%
Tuesday 2 8%
Wednesday 2 8%
Thursday 7 29%
Friday 3 12%
Saturday 1 4%
Sunday 4 17%

Pattern Analysis

3 Tracked Flights:
Data Points: 24
API observations used to build this analysis
Weekdays: 19 flights
Weekend: 5 flights
Business Route More active on weekdays

All Flight Routes

2 Routes
Note: This table shows aggregated route data by airline. Each airline may operate multiple daily flights at different times. See the "Spotted Departure Times" section below for all observed departure times.
Airline Flight Numbers Aircraft Type Typical Time Days Active Last Seen Status
B739 06:00 6:00 AM (Representative)
M T W T F S S
Jul 12, 2026 Active
Southwest
SWA / WN
- B739 -
M T W T F S S
Jul 12, 2026 Active
Total Routes: 2
Active Routes: 2
Unique Airlines: 2
Aircraft Types: 2

Spotted Departure Times

Departure Time Operator ICAO IATA
06:00 6:00 AM Alaska Airlines ASA AS

Time Information

Times are shown in the departure airport's local timezone (KSTL - America/Chicago).

Total Departure Times: 1
Time Range:
06:00 - 06:00
These are typical departure times observed from actual flights. Times may vary by season and schedule changes.