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Fly from
Fly to
Route
Depart
Return
St. LouisSeattle
STL Lambert-St Louis - SEA Seattle/Tacoma Intl
STLSEA
Lambert-St Louis
Mon 26/10
17:50-0:40
2 stops8h 50m
Seattle/Tacoma Intl
Thu 29/10
8:05-23:25
1 stop13h 20m
St. LouisSeattle
STL Lambert-St Louis - SEA Seattle/Tacoma Intl
STLSEA
Lambert-St Louis
Wed 3/3
6:45-14:23
1 stop9h 38m
Seattle/Tacoma Intl
Mon 8/3
13:45-23:18
1 stop7h 33m
St. LouisSeattle
STL Lambert-St Louis - SEA Seattle/Tacoma Intl
STLSEA
Lambert-St Louis
Sat 24/10
8:25-20:30
1 stop14h 05m
Seattle/Tacoma Intl
Mon 26/10
0:10-10:50
1 stop8h 40m
St. LouisSeattle
STL Lambert-St Louis - SEA Seattle/Tacoma Intl
STLSEA
Lambert-St Louis
Tue 3/11
14:35-22:15
2 stops9h 40m
Seattle/Tacoma Intl
Tue 10/11
5:40-17:25
2 stops9h 45m
St. LouisSeattle
STL Lambert-St Louis - SEA Seattle/Tacoma Intl
STLSEA
Lambert-St Louis
Wed 21/10
14:35-21:45
2 stops9h 10m
Seattle/Tacoma Intl
Sat 24/10
14:15-22:55
1 stop6h 40m
St. LouisSeattle
STL Lambert-St Louis - SEA Seattle/Tacoma Intl
STLSEA
Lambert-St Louis
Thu 5/11
8:00-14:39
1 stop8h 39m
Seattle/Tacoma Intl
Wed 11/11
7:00-15:43
1 stop6h 43m
St. LouisSeattle
STL Lambert-St Louis - SEA Seattle/Tacoma Intl
STLSEA
Lambert-St Louis
Fri 13/11
16:50-23:05
1 stop8h 15m
Seattle/Tacoma Intl
Fri 4/12
5:40-17:25
2 stops9h 45m
St. LouisSeattle
STL Lambert-St Louis - SEA Seattle/Tacoma Intl
STLSEA
Lambert-St Louis
Mon 14/12
11:20-17:50
1 stop8h 30m
Seattle/Tacoma Intl
Thu 17/12
21:25-12:25
1 stop13h 00m
St. LouisSeattle
STL Lambert-St Louis - SEA Seattle/Tacoma Intl
STLSEA
Lambert-St Louis
Sat 24/10
6:02-8:33
Nonstop4h 31m
Seattle/Tacoma Intl
Sat 31/10
9:40-15:44
Nonstop4h 04m
St. LouisSeattle
STL Lambert-St Louis - SEA Seattle/Tacoma Intl
STLSEA
Lambert-St Louis
Thu 7/1
14:30-21:50
2 stops9h 20m
Seattle/Tacoma Intl
Mon 18/1
0:15-11:20
1 stop9h 05m
See travel insights to Seattle from
How to get the cheapest flight ticket from St. Louis to Seattle
Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip
What is the typical price of a round-trip flight between St. Louis and Seattle?
Prices are currently low for flights on this route.
Typical prices usually range from R4 098 to R7 882.The lowest price recently found on this route was R3 635.
What is the cheapest month to fly to Seattle?
The cheapest month to fly to Seattle from St. Louis is in February. Flight prices, which tend to average around R3 916, are often lower during this time because this is during the off-season. If you aren’t able to travel to Seattle during the month of February, then flying in March is also cheap. Prices for this month can be found on momondo for an average of R4 776.
How far in advance should I book a flight from St. Louis to Seattle?
You are more likely to see cheaper flights to Seattle from St. Louis when booking weeks ahead of your departure date. In general, you can expect to find flights to Seattle for around R6 161 when searching weeks before you fly. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Seattle from St. Louis for as low as R5 304 on momondo.
How many flights depart from St. Louis to Seattle on average per day?
The number of flights available between St. Louis and Seattle is 3 per day as of October 2026. The most frequent departure time is 6:00, with 53% of daily flights leaving at midday.
How many flights depart from St. Louis to Seattle on average per week?
21 flights are operational weekly from St. Louis to Seattle as of October 2026. The most popular departure day for this route is Fri, with 29% of flights per week taking off on this day.
When to book flights from St. Louis to Seattle
Cheap St. Louis to Seattle (STL to SEA) flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from St. Louis to Seattle
Frequently asked questions about flying from St. Louis to Seattle
How far is Lambert-St Louis to Seattle/Tacoma Intl by plane?
There are 2767,4 km between Lambert-St Louis and Seattle/Tacoma Intl.
When did momondo last update prices for flights from Lambert-St Louis Airport to Seattle/Tacoma Intl Airport?
Prices for flights from Lambert-St Louis Airport to Seattle/Tacoma Intl Airport refresh daily.
How old do you have to be to fly from Lambert-St Louis Airport to Seattle/Tacoma Intl Airport?
The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and stopovers. It is recommended that you verify with the airline you are booking with for travel from Lambert-St Louis Airport to Seattle/Tacoma Intl Airport.
What documentation or ID do you need to fly to Seattle/Tacoma Intl Airport?
The travel and health documents you'll need for your trip to Seattle/Tacoma Intl Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's licence and a passport that is valid for six months after your intended arrival at Seattle/Tacoma Intl Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.
What is the most popular plane model from St. Louis to Seattle?
Based on momondo bookings for flights between St. Louis and Seattle, the leading plane model is Boeing 737, making up 50,50% of the total bookings. Other popular models include Boeing 737-800 Passenger/BBJ2 (winglets) with 24,45%, Boeing 737 MAX 8 with 11,53%, and Boeing 737-900 Passenger/BBJ3 (winglets) with 2,98%.
Travelling to a place near Seattle?
Book flights to Seattle if you plan to visit one of these locationsWhy use momondo?
Why should I use momondo to find a flight deal from St. Louis to Seattle?
momondo collates all your flight options in one place and lets you filter them to find the perfect flight from St. Louis to Seattle. momondo saves you time and could save you money on your trip.
Can I find flights from St. Louis to Seattle with flexible booking policies on momondo?
Yes. momondo enables you to select and highlight flights to Seattle from St. Louis with this policy.
How can momondo help me find flights from St. Louis to Seattle?
momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from St. Louis to Seattle.
I’m not ready to book a flight from St. Louis to Seattle right now. Can momondo alert me if prices change?
Price alerts on flights to Seattle from St. Louis are quick and easy to set up on momondo. Simply perform a search and select the price alert feature. It is as simple as that.