$120+ Cheap flights from St. Louis (STL) to Washington
This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 9/10. Fares are subject to change and may not be available on all flights or dates of travel.
STL — SEA
Jul 23 — Jul 301
Round-trip
1 adult, Economy
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Find cheap flights from St. Louis to Washington 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
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Cheapest flights from St. Louis to WashingtonExplore the most affordable flight options available from St. Louis to Washington. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 23, 2026.
Explore the most affordable flight options available from St. Louis to Washington. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 23, 2026.
This CheapOair deal was found by Cheapflights users on 6/21. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/57:03 pm
STL
- PDX
1 stop25h 01m
Frontier
Wed 8/125:21 pm
PDX
- STL
1 stop24h 02m
Frontier
Deal found 6/21![Frontier logo]()
$275
This CheapOair deal was found by Cheapflights users on 6/19. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/298:08 pm
STL
- PDX
1 stop22h 43m
Frontier
Mon 8/35:49 pm
PDX
- STL
1 stop22h 16m
Frontier
Deal found 6/19![Frontier logo]()
$285
This CheapOair deal was found by Cheapflights users on 6/21. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/178:10 pm
STL
- PDX
1 stop22h 25m
Frontier
Mon 9/219:34 pm
PDX
- STL
1 stop12h 17m
Frontier
Deal found 6/21![Frontier logo]()
$286
This CheapOair deal was found by Cheapflights users on 6/21. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/78:08 pm
STL
- PDX
1 stop22h 28m
Frontier
Tue 7/145:16 pm
PDX
- STL
1 stop24h 07m
Frontier
Deal found 6/21![Frontier logo]()
$289
This Kiwi.com deal was found by Cheapflights users on 6/21. 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 7/167:10 pm
STL
- PSC
1 stop26h 48m
Multiple Airlines
Mon 7/208:48 pm
PSC
- STL
1 stop19h 17m
Multiple Airlines
Deal found 6/21![Multiple Airlines logo]()
$289
This Travelocity deal was found by Cheapflights users on 6/20. 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 Travelocity is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/196:08 pm
STL
- PDX
Nonstop4h 12m
Multiple Airlines
Mon 9/219:34 pm
PDX
- STL
1 stop12h 17m
Multiple Airlines
Deal found 6/20![Multiple Airlines logo]()
$294
This Trip.com deal was found by Cheapflights users on 6/19. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/167:10 pm
STL
- PDX
1 stop23h 44m
Frontier
Thu 7/236:49 pm
PDX
- STL
1 stop21h 26m
Frontier
Deal found 6/19![Frontier logo]()
$297
This Southwest deal was found by Cheapflights users on 6/18. 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 8/88:30 am
STL
- PDX
Nonstop4h 10m
Southwest
Mon 8/1011:30 pm
PDX
- STL
1 stop8h 05m
Southwest
Deal found 6/18![Southwest logo]()
$309
This CheapOair deal was found by Cheapflights users on 6/21. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/37:38 pm
STL
- PDX
1 stop23h 19m
Frontier
Fri 7/105:49 pm
PDX
- STL
1 stop22h 26m
Frontier
Deal found 6/21![Frontier logo]()
$311
This Expedia deal was found by Cheapflights users on 6/20. 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.
Mon 9/288:10 pm
STL
- PDX
1 stop20h 17m
Frontier
Mon 10/59:34 pm
PDX
- STL
1 stop12h 17m
Frontier
Deal found 6/20![Frontier logo]()
$312
This CheapOair deal was found by Cheapflights users on 6/21. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/78:08 pm
STL
- PDX
1 stop22h 43m
Frontier
Wed 8/125:21 pm
PDX
- STL
1 stop24h 02m
Frontier
Deal found 6/21![Frontier logo]()
$314
This CheapOair deal was found by Cheapflights users on 6/21. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/178:08 pm
STL
- PDX
1 stop22h 43m
Frontier
Tue 7/215:16 pm
PDX
- STL
1 stop24h 07m
Frontier
Deal found 6/21![Frontier logo]()
$315
Best flights from St. Louis to WashingtonDiscover carefully curated flight deals from St. Louis to Washington that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated June 23, 2026.
Discover carefully curated flight deals from St. Louis to Washington that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated June 23, 2026.
This Southwest deal was found by Cheapflights users on 6/22. 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.
Sun 8/307:30 pm
STL
- PDX
1 stop6h 00m
Southwest
Sun 9/68:45 am
PDX
- STL
1 stop6h 15m
Southwest
Deal found 6/22![Southwest logo]()
$319
This Alaska Airlines deal was found by Cheapflights users on 6/19. 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 9/126:08 pm
STL
- PDX
Nonstop4h 12m
Alaska Airlines
Sat 9/1911:16 am
PDX
- STL
Nonstop3h 54m
Alaska Airlines
Deal found 6/19![Alaska Airlines logo]()
$337
This Delta deal was found by Cheapflights users on 6/22. 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 8/125:34 pm
STL
- GEG
1 stop7h 35m
Delta
Wed 8/196:45 am
GEG
- STL
1 stop7h 59m
Delta
Deal found 6/22![Delta logo]()
$363
This United Airlines deal was found by Cheapflights users on 6/18. 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.
Sat 8/151:36 pm
STL
- PDX
1 stop6h 14m
United Airlines
Sat 8/2210:50 am
PDX
- STL
2 stops9h 10m
United Airlines
Deal found 6/18![United Airlines logo]()
$424
This Southwest deal was found by Cheapflights users on 6/21. 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.
Sun 9/276:00 am
STL
- PDX
1 stop8h 45m
Southwest
Wed 9/307:50 am
PDX
- STL
2 stops8h 00m
Southwest
Deal found 6/21![Southwest logo]()
$353
This Alaska Airlines deal was found by Cheapflights users on 6/22. 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 9/296:29 am
STL
- PDX
1 stop6h 51m
Alaska Airlines
Wed 9/3011:16 am
PDX
- STL
Nonstop3h 54m
Alaska Airlines
Deal found 6/22![Alaska Airlines logo]()
$367
This Delta deal was found by Cheapflights users on 6/18. 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 9/28:00 am
STL
- GEG
1 stop6h 22m
Delta
Sun 9/66:45 am
GEG
- STL
1 stop7h 59m
Delta
Deal found 6/18![Delta logo]()
$373
This Southwest deal was found by Cheapflights users on 6/22. 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 8/127:00 am
STL
- GEG
2 stops8h 05m
Southwest
Tue 8/1812:35 pm
GEG
- STL
1 stop8h 10m
Southwest
Deal found 6/22![Southwest logo]()
$368
This United Airlines deal was found by Cheapflights users on 6/18. 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.
Wed 9/21:36 pm
STL
- GEG
2 stops11h 00m
United Airlines
Sun 9/65:00 am
GEG
- STL
1 stop5h 40m
United Airlines
Deal found 6/18![United Airlines logo]()
$425
This Delta deal was found by Cheapflights users on 6/19. 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.
Sun 11/16:30 am
STL
- SEA
1 stop6h 25m
Delta
Tue 11/1711:45 am
SEA
- STL
1 stop6h 52m
Delta
Deal found 6/19![Delta logo]()
$397
This Alaska Airlines deal was found by Cheapflights users on 6/18. 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 8/256:08 pm
STL
- GEG
1 stop7h 03m
Alaska Airlines
Wed 8/265:52 am
GEG
- STL
1 stop6h 14m
Alaska Airlines
Deal found 6/18![Alaska Airlines logo]()
$403
This Southwest deal was found by Cheapflights users on 6/22. 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.
Thu 9/105:30 pm
STL
- GEG
1 stop6h 30m
Southwest
Tue 9/156:15 am
GEG
- STL
2 stops9h 40m
Southwest
Deal found 6/22![Southwest logo]()
$393
This United Airlines deal was found by Cheapflights users on 6/21. 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.
Wed 9/28:00 am
STL
- SEA
2 stops13h 08m
United Airlines
Sat 9/511:59 pm
SEA
- STL
1 stop8h 11m
United Airlines
Deal found 6/21![United Airlines logo]()
$433
This Alaska Airlines deal was found by Cheapflights users on 6/20. 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 10/287:00 am
STL
- PSC
1 stop8h 18m
Alaska Airlines
Sat 10/311:55 pm
PSC
- STL
1 stop8h 04m
Alaska Airlines
Deal found 6/20![Alaska Airlines logo]()
$425
This Southwest deal was found by Cheapflights users on 6/22. 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.
Thu 10/17:35 pm
STL
- PDX
1 stop7h 35m
Southwest
Sun 10/48:30 am
PDX
- STL
2 stops8h 45m
Southwest
Deal found 6/22![Southwest logo]()
$394
This United Airlines deal was found by Cheapflights users on 6/19. 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 10/168:00 am
STL
- SEA
2 stops14h 37m
United Airlines
Mon 10/1911:59 pm
SEA
- STL
1 stop8h 11m
United Airlines
Deal found 6/19![United Airlines logo]()
$434
This Delta deal was found by Cheapflights users on 6/19. 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 7/297:55 pm
STL
- GEG
1 stop6h 00m
Delta
Wed 8/122:05 pm
GEG
- STL
1 stop7h 21m
Delta
Deal found 6/19![Delta logo]()
$440
This United Airlines deal was found by Cheapflights users on 6/20. 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.
Tue 8/188:00 am
STL
- SEA
2 stops13h 08m
United Airlines
Wed 8/1911:59 pm
SEA
- STL
1 stop8h 11m
United Airlines
Deal found 6/20![United Airlines logo]()
$434
This Delta deal was found by Cheapflights users on 6/21. 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.
Thu 8/67:45 pm
STL
- GEG
1 stop6h 08m
Delta
Mon 8/105:00 pm
GEG
- STL
1 stop5h 41m
Delta
Deal found 6/21![Delta logo]()
$440
This Southwest deal was found by Cheapflights users on 6/22. 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 7/184:45 pm
STL
- PDX
1 stop7h 40m
Southwest
Sat 7/255:00 am
PDX
- STL
2 stops8h 55m
Southwest
Deal found 6/22![Southwest logo]()
$404
This Alaska Airlines deal was found by Cheapflights users on 6/18. 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 11/311:39 am
STL
- SEA
2 stops11h 02m
Alaska Airlines
Tue 11/179:00 am
SEA
- STL
2 stops12h 56m
Alaska Airlines
Deal found 6/18![Alaska Airlines logo]()
$468
This United Airlines deal was found by Cheapflights users on 6/20. 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.
Tue 8/111:36 pm
STL
- SEA
2 stops9h 07m
United Airlines
Thu 8/2711:59 pm
SEA
- STL
1 stop8h 11m
United Airlines
Deal found 6/20![United Airlines logo]()
$457
This Southwest deal was found by Cheapflights users on 6/22. 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.
Thu 9/38:25 am
STL
- PDX
1 stop7h 00m
Southwest
Tue 9/87:50 am
PDX
- STL
2 stops8h 55m
Southwest
Deal found 6/22![Southwest logo]()
$422
This Alaska Airlines deal was found by Cheapflights users on 6/18. 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 10/277:00 am
STL
- PSC
1 stop8h 18m
Alaska Airlines
Sat 10/311:55 pm
PSC
- STL
1 stop8h 04m
Alaska Airlines
Deal found 6/18![Alaska Airlines logo]()
$480
This Southwest deal was found by Cheapflights users on 6/18. 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 8/82:05 pm
STL
- GEG
2 stops8h 50m
Southwest
Sat 8/157:05 am
GEG
- STL
2 stops7h 45m
Southwest
Deal found 6/18![Southwest logo]()
$423
This Delta deal was found by Cheapflights users on 6/19. 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 7/157:55 pm
STL
- PSC
1 stop5h 59m
Delta
Sun 7/195:21 pm
PSC
- STL
1 stop5h 20m
Delta
Deal found 6/19![Delta logo]()
$525
This Alaska Airlines deal was found by Cheapflights users on 6/21. 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 9/810:16 am
STL
- SEA
2 stops10h 36m
Alaska Airlines
Thu 9/108:40 am
SEA
- STL
1 stop9h 05m
Alaska Airlines
Deal found 6/21![Alaska Airlines logo]()
$482
This Southwest deal was found by Cheapflights users on 6/22. 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.
Sun 9/205:50 am
STL
- SEA
2 stops10h 10m
Southwest
Wed 9/3011:10 am
SEA
- STL
2 stops9h 00m
Southwest
Deal found 6/22![Southwest logo]()
$427
This United Airlines deal was found by Cheapflights users on 6/19. 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.
Tue 10/2711:25 am
STL
- PSC
2 stops11h 23m
United Airlines
Sat 10/315:15 am
PSC
- STL
2 stops8h 26m
United Airlines
Deal found 6/19![United Airlines logo]()
$535
This Southwest deal was found by Cheapflights users on 6/22. 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 9/211:45 pm
STL
- SEA
2 stops9h 30m
Southwest
Mon 9/2812:55 pm
SEA
- STL
2 stops9h 40m
Southwest
Deal found 6/22![Southwest logo]()
$427
Last-minute flights from St. Louis to WashingtonDiscover last-minute flight deals from St. Louis to Washington. Data last updated June 23, 2026 and is based on user searches.
Discover last-minute flight deals from St. Louis to Washington. Data last updated June 23, 2026 and is based on user searches.
This CheapOair deal was found by Cheapflights users on 6/18. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 6/277:38 pm
STL
- PDX
1 stop23h 19m
Frontier
Thu 7/212:26 pm
PDX
- STL
1 stop28h 27m
Frontier
Deal found 6/18![Frontier logo]()
$331
This CheapOair deal was found by Cheapflights users on 6/19. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/27:38 pm
STL
- PDX
1 stop23h 19m
Frontier
Fri 7/105:49 pm
PDX
- STL
1 stop22h 26m
Frontier
Deal found 6/19![Frontier logo]()
$322
This CheapOair deal was found by Cheapflights users on 6/21. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/37:38 pm
STL
- PDX
1 stop23h 19m
Frontier
Fri 7/105:49 pm
PDX
- STL
1 stop22h 26m
Frontier
Deal found 6/21![Frontier logo]()
$311
This CheapOair deal was found by Cheapflights users on 6/21. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/78:08 pm
STL
- PDX
1 stop22h 28m
Frontier
Tue 7/145:16 pm
PDX
- STL
1 stop24h 07m
Frontier
Deal found 6/21![Frontier logo]()
$289
This Kiwi.com deal was found by Cheapflights users on 6/21. 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 7/167:10 pm
STL
- PSC
1 stop26h 48m
Multiple Airlines
Mon 7/208:48 pm
PSC
- STL
1 stop19h 17m
Multiple Airlines
Deal found 6/21![Multiple Airlines logo]()
$289
This Trip.com deal was found by Cheapflights users on 6/19. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/167:10 pm
STL
- PDX
1 stop23h 44m
Frontier
Thu 7/236:49 pm
PDX
- STL
1 stop21h 26m
Frontier
Deal found 6/19![Frontier logo]()
$297
This CheapOair deal was found by Cheapflights users on 6/21. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/178:08 pm
STL
- PDX
1 stop22h 43m
Frontier
Tue 7/215:16 pm
PDX
- STL
1 stop24h 07m
Frontier
Deal found 6/21![Frontier logo]()
$315
This American Airlines deal was found by Cheapflights users on 6/20. 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.
Sat 7/187:24 pm
STL
- PDX
1 stop7h 31m
American Airlines
Sat 7/2511:15 pm
PDX
- STL
1 stop7h 22m
American Airlines
Deal found 6/20![American Airlines logo]()
$319
This Southwest deal was found by Cheapflights users on 6/22. 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 7/221:40 pm
STL
- PDX
1 stop8h 25m
Southwest
Wed 7/295:25 am
PDX
- STL
2 stops10h 50m
Southwest
Deal found 6/22![Southwest logo]()
$324
This CheapOair deal was found by Cheapflights users on 6/22. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/237:10 pm
STL
- PDX
1 stop23h 44m
Frontier
Sun 7/266:49 pm
PDX
- STL
1 stop21h 26m
Frontier
Deal found 6/22![Frontier logo]()
$341
This CheapOair deal was found by Cheapflights users on 6/19. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/298:08 pm
STL
- PDX
1 stop22h 43m
Frontier
Mon 8/35:49 pm
PDX
- STL
1 stop22h 16m
Frontier
Deal found 6/19![Frontier logo]()
$285
This Delta deal was found by Cheapflights users on 6/21. 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 7/297:55 pm
STL
- GEG
1 stop6h 00m
Delta
Wed 8/125:00 pm
GEG
- STL
1 stop5h 41m
Delta
Deal found 6/21![Delta logo]()
$363
One-way flights from St. Louis to WashingtonSearch for one-way flight options from St. Louis to Washington. Find affordable one-way fares based on user searches. Data last updated June 23, 2026.
Search for one-way flight options from St. Louis to Washington. Find affordable one-way fares based on user searches. Data last updated June 23, 2026.
This Frontier deal was found by Cheapflights users on 6/23. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/1012:46 pm
STL
- PDX
1 stop9h 53m
Frontier
Deal found 6/23![Frontier logo]()
$120
This Kiwi.com deal was found by Cheapflights users on 6/18. 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.
Wed 8/196:45 pm
STL
- GEG
1 stop16h 37m
Multiple Airlines
Deal found 6/18![Multiple Airlines logo]()
$121
This Kiwi.com deal was found by Cheapflights users on 6/21. 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 8/206:45 pm
STL
- SEA
1 stop17h 54m
Frontier
Deal found 6/21![Frontier logo]()
$125
This Kiwi.com deal was found by Cheapflights users on 6/19. 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.
Tue 8/186:45 pm
STL
- SEA
1 stop17h 54m
Frontier
Deal found 6/19![Frontier logo]()
$126
This Kiwi.com deal was found by Cheapflights users on 6/21. 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.
Wed 8/196:45 pm
STL
- SEA
1 stop17h 54m
Frontier
Deal found 6/21![Frontier logo]()
$128
This Trip.com deal was found by Cheapflights users on 6/20. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/218:08 pm
STL
- PDX
1 stop22h 28m
Frontier
Deal found 6/20![Frontier logo]()
$129
This Super.com deal was found by Cheapflights users on 6/21. 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.
Tue 7/147:03 pm
STL
- SEA
1 stop17h 36m
Frontier
Deal found 6/21![Frontier logo]()
$129
This CheapOair deal was found by Cheapflights users on 6/23. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/237:10 pm
STL
- PDX
1 stop23h 44m
Frontier
Deal found 6/23![Frontier logo]()
$131
This Super.com deal was found by Cheapflights users on 6/22. 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.
Tue 7/77:03 pm
STL
- SEA
1 stop17h 36m
Frontier
Deal found 6/22![Frontier logo]()
$131
This Super.com deal was found by Cheapflights users on 6/20. 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.
Sun 8/167:10 pm
STL
- SEA
1 stop17h 58m
Frontier
Deal found 6/20![Frontier logo]()
$132
This CheapOair deal was found by Cheapflights users on 6/21. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/712:46 pm
STL
- SEA
1 stop23h 14m
Frontier
Deal found 6/21![Frontier logo]()
$135
This Trip.com deal was found by Cheapflights users on 6/19. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/37:38 pm
STL
- SEA
1 stop16h 10m
Frontier
Deal found 6/19![Frontier logo]()
$136
Find flight deals from St. Louis to Washington
Keep the following information in mind while searching for St. Louis to Washington flight deals. Data was last updated June 23, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $275 (CheapOair) |
One-way from | $120 (Frontier) |
Popular in | July |
Cheapest in | February |
Average price | $464 |
Good round-trip deal | $474 or less |
Good one-way deal | $273 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from St. Louis to Washington 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 2,558,603 searches. Data last updated June 23, 2026.
Use the filters below to find and compare flights from St. Louis to Washington that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
St. LouisPortland
STL - PDX
STLPDX
Lambert-St Louis
Sun 8/30
7:30 pm-11:30 pm
1 stop6h 00m
Portland
Sun 9/6
8:45 am-5:00 pm
1 stop6h 15m
$319
Quickest round-trip
St. LouisPortland
STL - PDX
STLPDX
Lambert-St Louis
Sat 9/12
6:08 pm-8:20 pm
Nonstop4h 12m
Portland
Sat 9/19
11:16 am-5:10 pm
Nonstop3h 54m
$337
St. LouisPortland
STL - PDX
STLPDX
Lambert-St Louis
Sun 9/27
6:00 am-12:45 pm
1 stop8h 45m
Portland
Wed 9/30
7:50 am-5:50 pm
2 stops8h 00m
$353
St. LouisSpokane
STL - GEG
STLGEG
Lambert-St Louis
Wed 8/12
5:34 pm-11:09 pm
1 stop7h 35m
Spokane
Wed 8/19
6:45 am-4:44 pm
1 stop7h 59m
$363
St. LouisPortland
STL - PDX
STLPDX
Lambert-St Louis
Tue 9/29
6:29 am-11:20 am
1 stop6h 51m
Portland
Wed 9/30
11:16 am-5:10 pm
Nonstop3h 54m
$367
St. LouisSpokane
STL - GEG
STLGEG
Lambert-St Louis
Wed 8/12
7:00 am-1:05 pm
2 stops8h 05m
Spokane
Tue 8/18
12:35 pm-10:45 pm
1 stop8h 10m
$368
St. LouisSpokane
STL - GEG
STLGEG
Lambert-St Louis
Wed 9/2
8:00 am-12:22 pm
1 stop6h 22m
Spokane
Sun 9/6
6:45 am-4:44 pm
1 stop7h 59m
$373
St. LouisSpokane
STL - GEG
STLGEG
Lambert-St Louis
Thu 9/10
5:30 pm-10:00 pm
1 stop6h 30m
Spokane
Tue 9/15
6:15 am-5:55 pm
2 stops9h 40m
$393
St. LouisPortland
STL - PDX
STLPDX
Lambert-St Louis
Thu 10/1
7:35 pm-1:10 am
1 stop7h 35m
Portland
Sun 10/4
8:30 am-7:15 pm
2 stops8h 45m
$394
St. LouisSeattle
STL - SEA
STLSEA
Lambert-St Louis
Sun 11/1
6:30 am-10:55 am
1 stop6h 25m
Seattle/Tacoma Intl
Tue 11/17
11:45 am-8:37 pm
1 stop6h 52m
$397
Showing 1-10 of 60 resultsSorted by cheapest first
Best time to book a flight from St. Louis to Washington
Have a flexible travel schedule? Discover the best time to fly to Washington from St. Louis with our price prediction graph.
STL-PDX
STL-GEG
STL-SEA
STL-PSC
STL-YKM
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 Washington
STL-USWA
STL-PDX
STL-GEG
STL-SEA
STL-PSC
What is the cheapest month to book a flight from St. Louis to State of Washington?
Currently, March is the cheapest month in which you can book a flight from St. Louis to State of Washington (average of $80). Flying from St. Louis to State of Washington in June is currently the most expensive (average of $248). 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 WA?
Find hourly flight availability from St. Louis to Washington. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated June 23, 2026.
Unlike at noon, when flights are generally more expensive, you can save up to 12% on flights from St. Louis to State of Washington by exploring options for tickets in the afternoon.
Weekly flight availability from St. Louis to State of Washington
Explore weekly flight availability from St. Louis to Washington. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated June 23, 2026.
The most flights from STL to USWA are scheduled on a Monday (11 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (3 on average).
How much does it cost to fly round-trip from St. Louis to State of Washington?
How far ahead should I book a flight from St. Louis to State of Washington?
To ensure you get the cheapest price possible for a flight from St. Louis to State of Washington, you should look to book at least 55 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.
What is the cheapest day to fly from St. Louis to State of Washington?
Use this chart to determine the cheapest time to fly round-trip from St. Louis to Washington. Price data was last updated on June 20, 2026.
Travelers seeking maximum savings on their St. Louis to State of Washington flight should consider departing on Sunday afternoons when fares are most often at their lowest. Tuesday at noon flights should be avoided if possible as fares are typically the most expensive at this time.
Reviews of airlines servicing Washington
Get insights into the airlines that provide service to Washington. 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 Washington. Reviews last updated June 23, 2026.
Read through reviews of airlines operating flights from St. Louis to Washington, such as Alaska Airlines,Southwest, andDelta. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Comfort
7.8
Food
7.0
Entertainment
7.0
Boarding
8.1
Crew
8.5
Overall
7.9
Reviews
1 / 20
8.0
ExcellentAnonymous,Jun 2026
RDU - SEA
Comfort
7.8
Food
7.0
Entertainment
7.0
Boarding
8.1
Crew
8.5
Overall
7.9
Reviews
1 / 20
8.0
ExcellentAnonymous,Jun 2026
RDU - SEA
Comfort
7.8
Food
7.0
Entertainment
7.0
Boarding
8.1
Crew
8.5
Overall
7.9
Reviews
1 / 20
8.0
ExcellentAnonymous,Jun 2026
RDU - SEA
Comfort
7.8
Food
7.0
Entertainment
7.0
Boarding
8.1
Crew
8.5
Overall
7.9
Reviews
1 / 20
8.0
ExcellentAnonymous,Jun 2026
RDU - SEA
Comfort
7.8
Food
7.0
Entertainment
7.0
Boarding
8.1
Crew
8.5
Overall
7.9
Reviews
1 / 20
8.0
ExcellentAnonymous,Jun 2026
RDU - SEA
Comfort
7.8
Food
7.0
Entertainment
7.0
Boarding
8.1
Crew
8.5
Overall
7.9
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 Washington. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
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Complete your trip
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St. Louis and Washington flights
Browse other St. Louis and Washington flight options. Last updated on June 23, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
St. Louis to Washington flights
Consider these flights traveling from St. Louis to Washington.
Top 7 airlines flying from St. Louis to Washington
Discover the top 7 airlines that operate flights from St. Louis to Washington. 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 2,558,603 searches. Data last updated June 23, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$129 | Average$266 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$136 | Average$397 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$151 | Average$479 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$178 | Average$432 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$179 | Average$427 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$188 | Average$410 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$222 | Average$329 | FlexibilityNo cancel fee | On-time85% |