$75+ Cheap flights from St. Louis to Seattle (STL - SEA)
This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 10/30. Fares are subject to change and may not be available on all flights or dates of travel.
STL — SEA
Nov 9 — Nov 161
Round-trip
1 adult, Economy
We work with more than 300 partners to bring you better travel deals
Find cheap flights from St. Louis to Seattle with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.3. Compare prices and book
Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheapflights Tip: The best prices from Lambert-St Louis to Seattle/Tacoma Intl are usually found in February or March, booked 46 days in advance, depart on a Friday or Saturday and return on a Tuesday
Cheap flight deals from St. Louis to Seattle
Cheapest
Best
Last-minute
One-way
Cheapest flights from St. Louis to SeattleExplore the most affordable flight options available from St. Louis to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 10, 2026.
Explore the most affordable flight options available from St. Louis to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 10, 2026.
This Cheapflightsfares deal was found by Cheapflights users on 10/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/261:30 pm -
1 stop23h 29m
Thu 10/299:13 pm -
1 stop13h 20m
Deal found 10/9![Frontier logo]()
$219
This Southwest deal was found by Cheapflights users on 10/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/265:50 pm -
2 stops8h 50m
Thu 10/298:05 am -
1 stop13h 20m
Deal found 10/7![Southwest logo]()
$220
This Southwest deal was found by Cheapflights users on 10/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/411:20 am -
2 stops9h 20m
Wed 11/114:40 pm -
2 stops14h 50m
Deal found 10/10![Southwest logo]()
$221
This Southwest deal was found by Cheapflights users on 10/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/1212:10 pm -
2 stops10h 20m
Sat 1/96:05 am -
1 stop8h 00m
Deal found 10/9![Southwest logo]()
$222
This Southwest deal was found by Cheapflights users on 10/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/305:50 pm -
2 stops8h 50m
Mon 11/211:20 am -
2 stops11h 30m
Deal found 10/8![Southwest logo]()
$223
This Southwest deal was found by Cheapflights users on 10/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/32:35 pm -
2 stops9h 40m
Tue 11/105:40 am -
2 stops9h 45m
Deal found 10/7![Southwest logo]()
$225
This Kiwi.com deal was found by Cheapflights users on 10/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/121:28 pm -
1 stop22h 17m
Fri 11/204:37 pm -
2 stops21h 43m
Deal found 10/7![Frontier logo]()
$226
This Southwest deal was found by Cheapflights users on 10/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/212:35 pm -
2 stops9h 10m
Sat 10/242:15 pm -
1 stop6h 40m
Deal found 10/7![Southwest logo]()
$227
This American Airlines deal was found by Cheapflights users on 10/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/296:04 am -
1 stop9h 03m
Sat 10/3112:34 am -
1 stop9h 13m
Deal found 10/8![American Airlines logo]()
$228
This United Airlines deal was found by Cheapflights users on 10/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/58:00 am -
1 stop8h 39m
Wed 11/117:00 am -
1 stop6h 43m
Deal found 10/7![United Airlines logo]()
$229
This Expedia deal was found by Cheapflights users on 10/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/146:00 am -
Nonstop4h 36m
Tue 11/178:22 am -
Nonstop4h 03m
Deal found 10/6![Alaska Airlines logo]()
$231
This Southwest deal was found by Cheapflights users on 10/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/134:50 pm -
1 stop8h 15m
Fri 12/45:40 am -
2 stops9h 45m
Deal found 10/10![Southwest logo]()
$232
Best flights from St. Louis to SeattleDiscover carefully curated flight deals from St. Louis to Seattle that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated October 10, 2026.
Discover carefully curated flight deals from St. Louis to Seattle that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated October 10, 2026.
This Southwest deal was found by Cheapflights users on 10/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/1212:10 pm -
2 stops10h 20m
Sat 1/96:05 am -
1 stop8h 00m
Deal found 10/9![Southwest logo]()
$222
This Alaska Airlines deal was found by Cheapflights users on 10/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/63:23 pm -
Nonstop4h 30m
Fri 11/136:07 pm -
Nonstop3h 52m
Deal found 10/9![Alaska Airlines logo]()
$286
This Delta deal was found by Cheapflights users on 10/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/217:38 pm -
1 stop6h 37m
Sun 12/2711:59 pm -
1 stop8h 36m
Deal found 10/8![Delta logo]()
$397
This United Airlines deal was found by Cheapflights users on 10/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/67:05 pm -
1 stop7h 54m
Mon 11/96:30 pm -
2 stops14h 02m
Deal found 10/8![United Airlines logo]()
$423
This Southwest deal was found by Cheapflights users on 10/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/142:05 pm -
2 stops9h 05m
Thu 12/175:15 am -
2 stops11h 55m
Deal found 10/8![Southwest logo]()
$288
This Southwest deal was found by Cheapflights users on 10/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/168:25 am -
2 stops12h 40m
Thu 11/199:25 am -
1 stop8h 25m
Deal found 10/6![Southwest logo]()
$309
This Alaska Airlines deal was found by Cheapflights users on 10/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/176:00 am -
Nonstop4h 36m
Fri 11/206:08 pm -
Nonstop3h 51m
Deal found 10/7![Alaska Airlines logo]()
$343
This Southwest deal was found by Cheapflights users on 10/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/115:30 am -
1 stop7h 05m
Sun 11/156:25 pm -
2 stops15h 25m
Deal found 10/5![Southwest logo]()
$323
This Alaska Airlines deal was found by Cheapflights users on 10/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/226:04 am -
Nonstop4h 42m
Tue 12/296:04 pm -
Nonstop3h 54m
Deal found 10/5![Alaska Airlines logo]()
$357
This Alaska Airlines deal was found by Cheapflights users on 10/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/246:00 am -
Nonstop4h 40m
Tue 12/18:00 am -
1 stop13h 58m
Deal found 10/10![Alaska Airlines logo]()
$378
This Southwest deal was found by Cheapflights users on 10/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/248:25 am -
2 stops13h 40m
Tue 10/279:00 am -
2 stops6h 45m
Deal found 10/5![Southwest logo]()
$355
This Alaska Airlines deal was found by Cheapflights users on 10/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/236:04 am -
Nonstop4h 42m
Tue 12/296:04 pm -
Nonstop3h 54m
Deal found 10/8![Alaska Airlines logo]()
$422
Last-minute flights from St. Louis to SeattleDiscover last-minute flight deals from St. Louis to Seattle. Data last updated October 10, 2026 and is based on user searches.
Discover last-minute flight deals from St. Louis to Seattle. Data last updated October 10, 2026 and is based on user searches.
This Southwest deal was found by Cheapflights users on 10/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/212:35 pm -
2 stops9h 10m
Sat 10/242:15 pm -
1 stop6h 40m
Deal found 10/7![Southwest logo]()
$227
This Southwest deal was found by Cheapflights users on 10/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/248:25 am -
1 stop14h 05m
Mon 10/2612:10 am -
1 stop8h 40m
Deal found 10/5![Southwest logo]()
$223
This Alaska Airlines deal was found by Cheapflights users on 10/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/246:02 am -
Nonstop4h 31m
Sat 10/319:40 am -
Nonstop4h 04m
Deal found 10/6![Alaska Airlines logo]()
$234
This Cheapflightsfares deal was found by Cheapflights users on 10/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/261:30 pm -
1 stop23h 29m
Thu 10/299:13 pm -
1 stop13h 20m
Deal found 10/9![Frontier logo]()
$219
This Southwest deal was found by Cheapflights users on 10/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/265:50 pm -
2 stops8h 50m
Thu 10/298:05 am -
1 stop13h 20m
Deal found 10/7![Southwest logo]()
$220
This American Airlines deal was found by Cheapflights users on 10/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/296:04 am -
1 stop9h 03m
Sat 10/3112:34 am -
1 stop9h 13m
Deal found 10/8![American Airlines logo]()
$228
This Southwest deal was found by Cheapflights users on 10/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/32:35 pm -
2 stops9h 40m
Tue 11/105:40 am -
2 stops9h 45m
Deal found 10/7![Southwest logo]()
$225
This United Airlines deal was found by Cheapflights users on 10/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/58:00 am -
1 stop8h 39m
Wed 11/117:00 am -
1 stop6h 43m
Deal found 10/7![United Airlines logo]()
$229
This American Airlines deal was found by Cheapflights users on 10/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/107:26 am -
1 stop8h 54m
Fri 11/1312:47 pm -
1 stop8h 46m
Deal found 10/5![American Airlines logo]()
$222
This Kiwi.com deal was found by Cheapflights users on 10/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/121:28 pm -
1 stop22h 17m
Fri 11/204:37 pm -
2 stops21h 43m
Deal found 10/7![Frontier logo]()
$226
This Southwest deal was found by Cheapflights users on 10/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/134:50 pm -
1 stop8h 15m
Fri 12/45:40 am -
2 stops9h 45m
Deal found 10/10![Southwest logo]()
$232
This Expedia deal was found by Cheapflights users on 10/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/146:00 am -
Nonstop4h 36m
Tue 11/178:22 am -
Nonstop4h 03m
Deal found 10/6![Alaska Airlines logo]()
$231
One-way flights from St. Louis to SeattleSearch for one-way flight options from St. Louis to Seattle. Find affordable one-way fares based on user searches. Data last updated October 10, 2026.
Search for one-way flight options from St. Louis to Seattle. Find affordable one-way fares based on user searches. Data last updated October 10, 2026.
This Super.com deal was found by Cheapflights users on 10/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/301:28 pm -
1 stop23h 31m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/8![Frontier logo]()
$75
This Southwest deal was found by Cheapflights users on 10/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/311:20 am -
1 stop8h 30m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/6![Southwest logo]()
$79
This Southwest deal was found by Cheapflights users on 10/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/315:05 am -
1 stop7h 20m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/8![Southwest logo]()
$80
This Kiwi.com deal was found by Cheapflights users on 10/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/67:59 pm -
1 stop21h 13m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/7![Frontier logo]()
$87
This Kiwi.com deal was found by Cheapflights users on 10/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/261:30 pm -
1 stop23h 29m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/5![Frontier logo]()
$88
This Delta deal was found by Cheapflights users on 10/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/286:21 am -
1 stop8h 09m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/7![Delta logo]()
$89
This Southwest deal was found by Cheapflights users on 10/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/266:10 pm -
1 stop8h 30m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/6![Southwest logo]()
$90
This Delta deal was found by Cheapflights users on 10/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/212:22 pm -
1 stop6h 40m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/6![Delta logo]()
$93
This Southwest deal was found by Cheapflights users on 10/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/202:35 pm -
2 stops9h 10m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/6![Southwest logo]()
$98
This Alaska Airlines deal was found by Cheapflights users on 10/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/86:04 am -
Nonstop4h 46m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/7![Alaska Airlines logo]()
$99
This Priceline deal was found by Cheapflights users on 10/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/136:04 am -
Nonstop4h 46m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/8![Alaska Airlines logo]()
$104
Find flight deals from St. Louis to Seattle
Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Seattle (SEA). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated October 10, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $219 (Cheapflightsfares) |
One-way from | $75 (Super.com) |
Popular in | July |
Cheapest in | February |
Average price | $381 |
Good round-trip deal | $447 or less |
Good one-way deal | $229 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from St. Louis to Seattle that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 7,457,451 searches. Data last updated October 10, 2026.
Use the filters below to find and compare flights from St. Louis to Seattle that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
St. LouisSeattle
STL Lambert-St Louis - SEA Seattle/Tacoma Intl
STLSEA
Lambert-St Louis
Sat 10/31
5:05 am-10:25 am
1 stop7h 20m
Seattle/Tacoma Intl
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$80
St. LouisSeattle
STL Lambert-St Louis - SEA Seattle/Tacoma Intl
STLSEA
Lambert-St Louis
Mon 10/26
6:10 pm-12:40 am
1 stop8h 30m
Seattle/Tacoma Intl
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$90
St. LouisSeattle
STL Lambert-St Louis - SEA Seattle/Tacoma Intl
STLSEA
Lambert-St Louis
Tue 10/20
2:35 pm-9:45 pm
2 stops9h 10m
Seattle/Tacoma Intl
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$98
St. LouisSeattle
STL Lambert-St Louis - SEA Seattle/Tacoma Intl
STLSEA
Lambert-St Louis
Tue 12/8
6:04 am-8:50 am
Nonstop4h 46m
Seattle/Tacoma Intl
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$99
St. LouisSeattle
STL Lambert-St Louis - SEA Seattle/Tacoma Intl
STLSEA
Lambert-St Louis
Mon 10/26
7:00 pm-11:59 pm
1 stop6h 59m
Seattle/Tacoma Intl
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$106
St. LouisSeattle
STL Lambert-St Louis - SEA Seattle/Tacoma Intl
STLSEA
Lambert-St Louis
Fri 11/27
6:13 am-12:29 pm
1 stop8h 16m
Seattle/Tacoma Intl
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$110
St. LouisSeattle
STL Lambert-St Louis - SEA Seattle/Tacoma Intl
STLSEA
Lambert-St Louis
Thu 12/17
6:09 pm-11:16 pm
1 stop7h 07m
Seattle/Tacoma Intl
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$114
St. LouisSeattle
STL Lambert-St Louis - SEA Seattle/Tacoma Intl
STLSEA
Lambert-St Louis
Sun 11/8
7:15 pm-12:45 am
1 stop7h 30m
Seattle/Tacoma Intl
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$114
St. LouisSeattle
STL Lambert-St Louis - SEA Seattle/Tacoma Intl
STLSEA
Lambert-St Louis
Tue 12/1
6:00 am-3:27 pm
1 stop11h 27m
Seattle/Tacoma Intl
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$159
Quickest round-trip
St. LouisSeattle
STL Lambert-St Louis - SEA Seattle/Tacoma Intl
STLSEA
Lambert-St Louis
Thu 10/29
7:02 am-9:35 am
Nonstop4h 33m
Seattle/Tacoma Intl
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$161
Showing 1-10 of 24 resultsSorted by cheapest first
Compare providers for flights from St. Louis to Seattle
Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from St. Louis to Seattle in October.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy- | Trust Score*1 star | |
| Price Accuracy1 star | Trust Score*3 stars |
- Most accurate provider: When it comes to deals on St. Louis-Seattle flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on St. Louis-Seattle flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from St. Louis-Seattle flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on St. Louis-Seattle flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for St. Louis-Seattle flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.
Best time to book a flight from St. Louis to Seattle
Have a flexible travel schedule? Discover the best time to fly to Seattle from St. Louis with our price prediction graph.
STL-SEA
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.
Cheapflights Insights
Everything you need to know about your flight from St. Louis to Seattle
Prices
More
How far ahead should I book a flight from St. Louis to Seattle?
The best time to book flights from St. Louis to Seattle is 45 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.
What is the cheapest month to book a flight from St. Louis to Seattle?
Currently, February is the cheapest month in which you can book a flight from St. Louis to Seattle (average of $237). Flying from St. Louis to Seattle in July is currently the most expensive (average of $522). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.
What is the cheapest time of day to fly from STL to SEA?
Find hourly flight availability from St. Louis to Seattle. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated October 10, 2026.
Unlike at noon, when flights are generally more expensive, you can save up to 14% on flights from St. Louis to Seattle by exploring options for tickets in the evening.
What is the cheapest day to fly from St. Louis to Seattle?
Use this chart to determine the cheapest time to fly round-trip from St. Louis to Seattle. Price data was last updated on October 3, 2026.
Travelers seeking maximum savings on their St. Louis to Seattle flight should consider departing on Sunday afternoons when fares are most often at their lowest. Wednesday at noon flights should be avoided if possible as fares are typically the most expensive at this time.
What’s the top layover airport for flights from St. Louis to Seattle?
Share of 1-stop round-trip flights from St. Louis to Seattle chosen by Cheapflights users in the past 12 months, using the same layover each way.
Chicago (ORD) – chosen by Cheapflights users on 25% of 1-stop itineraries from St. Louis to Seattle on Cheapflights.
What’s the cheapest layover airport for flights from St. Louis to Seattle?
Average round-trip fare for 1-stop flights from St. Louis to Seattle, chosen by Cheapflights users in the past 12 months, with the same layover each way.
Denver (DEN) is the most affordable 1-stop option, with an average round-trip price of $248.
What’s the fastest layover option from St. Louis to Seattle?
Shortest average travel time for 1-stop one-way flights from St. Louis to Seattle, based on itineraries clicked by Cheapflights users over the past 12 months, grouped by layover airport.
Flights via Chicago (ORD) have the shortest average one-way travel time for 1-stop routes: 7h 15m.
Which airport typically offers the quickest layover for flights from St. Louis to Seattle?
Average layover duration for 1-stop one-way flights from St. Louis to Seattle, chosen by Cheapflights users in the last 12 months, grouped by stopover airport.
Flights via Chicago (ORD) offer the fastest connection on this route, with an average layover time of 0h 56m.
The best insider tips for St. Louis to Seattle flights
AI-powered summary based on content written by travel experts. AI can make mistakes.
Cheapflights partnered with top experts to bring you the best recommendations for your St. Louis to Seattle trip
Our travel experts
Reviews of airlines servicing Seattle
Get insights into the airlines that provide service to Seattle. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Seattle. Reviews last updated October 10, 2026.
Read through reviews of airlines operating flights from St. Louis to Seattle, such as Alaska Airlines,Southwest, andDelta. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Crew
8.5
Food
7.0
Boarding
8.1
Overall
7.9
Comfort
7.8
Entertainment
7.0
Reviews
1 / 20
8.0
ExcellentAnonymous,Jun 2026
RDU - SEA
Crew
8.5
Food
7.0
Boarding
8.1
Overall
7.9
Comfort
7.8
Entertainment
7.0
Reviews
1 / 20
8.0
ExcellentAnonymous,Jun 2026
RDU - SEA
Crew
8.5
Food
7.0
Boarding
8.1
Overall
7.9
Comfort
7.8
Entertainment
7.0
Reviews
1 / 20
8.0
ExcellentAnonymous,Jun 2026
RDU - SEA
Crew
8.5
Food
7.0
Boarding
8.1
Overall
7.9
Comfort
7.8
Entertainment
7.0
Reviews
1 / 20
8.0
ExcellentAnonymous,Jun 2026
RDU - SEA
Crew
8.5
Food
7.0
Boarding
8.1
Overall
7.9
Comfort
7.8
Entertainment
7.0
Reviews
1 / 20
8.0
ExcellentAnonymous,Jun 2026
RDU - SEA
Crew
8.5
Food
7.0
Boarding
8.1
Overall
7.9
Comfort
7.8
Entertainment
7.0
Reviews
1 / 20
8.0
ExcellentAnonymous,Jun 2026
RDU - SEA
Related info for your journey
Find useful and relevant information for your journey from St. Louis to Seattle. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
Traveling to a place near Seattle?
Book flights to Seattle if you plan to visit one of these locationsSeaTac
Renton
Tacoma
Lacey
Leavenworth
Olympia
Tukwila
Snoqualmie
Puyallup
Lynnwood
Centralia
Kent
Tumwater
Ocean Shores
Ellensburg
Issaquah
Marysville
Lakewood
Fife
Poulsbo
Browse thousands of different options on Cheapflights for your next trip
Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.
Alternative routes
Complete your trip
Flights by cabin class
Other flight options
Other flights from St. Louis
Popular flights
Seattle flight routes
Alternative routes for St. Louis to Seattle
See prices for flight routes from nearby airports that may be better suited for you.
Complete your trip
Complete your trip to Seattle by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from St. Louis to Seattle by cabin class
Find flights from St. Louis to Seattle, based on your preferred cabin class, be it economy, premium economy, business, or first class.
St. Louis and Seattle flights
Browse other St. Louis and Seattle flight options. Last updated on October 10, 2026.
Other flights from St. Louis
Browse through other flights departing from St. Louis. Flights are based on user searches made on Cheapflights and were last updated on October 10, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Other flights to Seattle
Explore flights to Seattle departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on October 10, 2026.
Top 6 airlines flying from St. Louis to Seattle
Discover the top 6 airlines that operate flights from St. Louis to Seattle. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 7,457,451 searches. Data last updated October 10, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$129 | Average$281 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$134 | Average$248 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$186 | Average$386 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$192 | Average$415 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$219 | Average$383 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$220 | Average$428 | FlexibilityNo cancel fee | On-time75% |