Seattle (SEA) to St Louis (STL)
Flight time
≈ 4h 13m
Bearing
99° E
Seattle (SEA) to St Louis (STL) is 1,705 miles (2,744 km) as the crow flies — the great-circle baseline most distance-based mileage programs credit.
Look up a route, or build a trip
Change the airports, or add stops for a multi-leg trip.
What actually flies SEA–STL
Filed traffic dataIn May 2026, Alaska Airlines was the only carrier flying nonstop SEA–STL; the Boeing 737 MAX 9 was the most common aircraft at 45% of departures; flights ran 82% full.
Departures
162
May 2026
Seats
28,492
both directions
Passengers
23,407
both directions
Load factor
82.2%
RPM ÷ ASM
Who flies SEA–STL?
Alaska Airlines was the only carrier to fly nonstop SEA–STL in May 2026 (162 departures).
- AS
162 departures · 28,492 seats
Share of departures100.0%82.2%
Load
What plane flies SEA–STL?
In May 2026, the Boeing 737 MAX 9 flew 45% of SEA–STL departures — more than any other aircraft type.
- Boeing 737 MAX 9
73 departures · 81.6% load
45.1% - Boeing 737-900ER
69 departures · 82.1% load
42.6% - Boeing 737-800
14 departures · 84.0% load
8.6% - Boeing 737 MAX 8
6 departures · 86.1% load
3.7%
How has SEA–STL traffic changed?
Nonstop SEA–STL departures fell from 231 in June 2025 to 162 in May 2026.
Monthly nonstop SEA–STL traffic, trailing 12 months through May 2026. Bars scale to the busiest month; months with no filed service show as zero.
June 2025
231 departures · 34,765 passengers
87.0%
Load
July 2025
244 departures · 37,550 passengers
89.4%
Load
August 2025
224 departures · 34,636 passengers
89.8%
Load
September 2025
197 departures · 29,437 passengers
87.6%
Load
October 2025
121 departures · 18,523 passengers
86.4%
Load
November 2025
100 departures · 15,096 passengers
85.9%
Load
December 2025
108 departures · 16,005 passengers
84.7%
Load
January 2026
73 departures · 10,723 passengers
83.0%
Load
February 2026
75 departures · 10,879 passengers
82.2%
Load
March 2026
102 departures · 16,029 passengers
88.8%
Load
April 2026
118 departures · 17,412 passengers
83.8%
Load
May 2026
162 departures · 23,407 passengers
82.2%
Load
By direction
Each direction is filed separately — they rarely match.
SEA → STL
75.0% full
81 departures · 10,685 passengers
STL → SEA
89.3% full
81 departures · 12,722 passengers
Nonstop SEA–STL traffic has been filed since 2025.
Source: US DOT BTS Form 41 T-100 Segment (All Carriers). Data through May 2026; filings from 2025. Public domain (US Government work).
The airports
Frequently asked
How far is Seattle (SEA) from St Louis (STL)?
SEA to STL is 1,705 miles (2,744 km / 1,482 nautical miles) measured great-circle — the shortest path over the surface of the Earth.
How long is the flight from SEA to STL?
A nonstop covers the 1,705-mile great-circle distance in roughly 4h 13m of block time, before winds. Actual schedules vary a few percent by direction and aircraft.
What plane flies SEA–STL?
In May 2026, the Boeing 737 MAX 9 flew the largest share of departures (45.1%), followed by the Boeing 737-900ER (42.6%).
What mileage do I earn flying SEA–STL?
Distance-based programs credit off the 1,705-mile great-circle figure, then apply your fare-class earning rate. Revenue-based programs credit off the fare instead.
Keep exploring
Every route below is its own page.
Popular long-haul routes