$126+ Cheap flights from Washington to St. Louis (STL)
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 9/21. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — STL
Jul 27 — Aug 31
Round-trip
1 adult, Economy
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Find cheap flights from Washington to St. Louis 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 Washington to St. LouisExplore the most affordable flight options available from Washington to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 27, 2026.
Explore the most affordable flight options available from Washington to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 27, 2026.
This Frontier deal was found by Cheapflights users on 6/24. 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.
Fri 9/119:34 pm
PDX
- STL
1 stop12h 17m
Frontier
Sun 9/1312:46 pm
STL
- PDX
1 stop9h 53m
Frontier
Deal found 6/24![Frontier logo]()
$240
This CheapOair deal was found by Cheapflights users on 6/24. 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 7/306:49 pm
PDX
- STL
1 stop21h 26m
Frontier
Fri 8/78:08 pm
STL
- PDX
1 stop22h 43m
Frontier
Deal found 6/24![Frontier logo]()
$250
This CheapOair deal was found by Cheapflights users on 6/25. 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 7/105:49 pm
PDX
- STL
1 stop22h 26m
Frontier
Fri 7/178:08 pm
STL
- PDX
1 stop22h 43m
Frontier
Deal found 6/25![Frontier logo]()
$259
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.
Mon 7/65:49 pm
PDX
- STL
1 stop22h 16m
Frontier
Thu 7/98:08 pm
STL
- PDX
1 stop22h 43m
Frontier
Deal found 6/22![Frontier logo]()
$268
This Frontier deal was found by Cheapflights users on 6/24. 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.
Fri 9/189:34 pm
PDX
- STL
1 stop12h 17m
Frontier
Mon 9/2112:46 pm
STL
- PDX
1 stop9h 53m
Frontier
Deal found 6/24![Frontier logo]()
$276
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.
Fri 7/175:49 pm
PDX
- STL
1 stop22h 26m
Frontier
Wed 7/228:08 pm
STL
- PDX
1 stop22h 43m
Frontier
Deal found 6/23![Frontier logo]()
$285
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.
Fri 8/286:17 pm
PDX
- STL
1 stop21h 33m
Frontier
Mon 8/317:58 pm
STL
- PDX
1 stop23h 13m
Frontier
Deal found 6/23![Frontier logo]()
$286
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.
Tue 7/145:16 pm
PDX
- STL
1 stop24h 07m
Frontier
Thu 7/167:10 pm
STL
- PDX
1 stop23h 44m
Frontier
Deal found 6/23![Frontier logo]()
$289
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.
Fri 7/105:49 pm
PDX
- STL
1 stop22h 26m
Frontier
Wed 7/158:08 pm
STL
- PDX
1 stop22h 43m
Frontier
Deal found 6/23![Frontier logo]()
$294
This Frontier deal was found by Cheapflights users on 6/24. 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.
Sun 9/209:34 pm
PDX
- STL
1 stop12h 17m
Frontier
Thu 10/112:46 pm
STL
- PDX
1 stop9h 53m
Frontier
Deal found 6/24![Frontier logo]()
$305
This Southwest deal was found by Cheapflights users on 6/24. 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 9/225:50 am
PDX
- STL
1 stop7h 15m
Southwest
Sat 9/268:30 am
STL
- PDX
Nonstop4h 10m
Southwest
Deal found 6/24![Southwest logo]()
$309
This American Airlines deal was found by Cheapflights users on 6/25. 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 8/42:29 pm
GEG
- STL
1 stop7h 47m
American Airlines
Tue 8/188:00 am
STL
- GEG
1 stop8h 09m
American Airlines
Deal found 6/25![American Airlines logo]()
$363
Best flights from Washington to St. LouisDiscover carefully curated flight deals from Washington to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated June 27, 2026.
Discover carefully curated flight deals from Washington to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated June 27, 2026.
This United Airlines deal was found by Cheapflights users on 6/24. 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 8/257:16 am
PDX
- STL
1 stop6h 22m
United Airlines
Thu 8/275:30 pm
STL
- PDX
1 stop7h 22m
United Airlines
Deal found 6/24![United Airlines logo]()
$319
This Southwest deal was found by Cheapflights users on 6/26. 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 8/1511:30 pm
PDX
- STL
1 stop7h 45m
Southwest
Sun 8/237:30 pm
STL
- PDX
1 stop6h 00m
Southwest
Deal found 6/26![Southwest logo]()
$319
This Alaska Airlines deal was found by Cheapflights users on 6/24. 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 9/228:31 am
GEG
- STL
1 stop8h 07m
Alaska Airlines
Sat 9/266:29 am
STL
- GEG
1 stop7h 08m
Alaska Airlines
Deal found 6/24![Alaska Airlines logo]()
$363
This Delta deal was found by Cheapflights users on 6/26. 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 9/215:15 pm
GEG
- STL
1 stop5h 29m
Delta
Sat 9/265:00 pm
STL
- GEG
1 stop6h 54m
Delta
Deal found 6/26![Delta logo]()
$388
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.
Fri 7/176:04 pm
SEA
- STL
Nonstop3h 55m
Multiple Airlines
Tue 7/218:08 pm
STL
- SEA
1 stop15h 09m
Multiple Airlines
Deal found 6/21![Multiple Airlines logo]()
$421
This American Airlines deal was found by Cheapflights users on 6/26. 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.
Wed 8/265:15 am
PSC
- STL
2 stops10h 50m
American Airlines
Mon 8/315:42 am
STL
- PSC
2 stops11h 06m
American Airlines
Deal found 6/26![American Airlines logo]()
$519
This Southwest deal was found by Cheapflights users on 6/26. 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 7/249:20 pm
PDX
- STL
1 stop8h 50m
Southwest
Fri 7/315:05 am
STL
- PDX
1 stop6h 50m
Southwest
Deal found 6/26![Southwest logo]()
$319
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/295:25 am
PDX
- STL
2 stops10h 50m
Southwest
Tue 8/412:20 pm
STL
- PDX
2 stops9h 30m
Southwest
Deal found 6/23![Southwest logo]()
$329
This Alaska Airlines deal was found by Cheapflights users on 6/25. 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 9/235:52 am
GEG
- STL
1 stop6h 29m
Alaska Airlines
Sat 9/266:29 am
STL
- GEG
1 stop8h 10m
Alaska Airlines
Deal found 6/25![Alaska Airlines logo]()
$363
This United Airlines deal was found by Cheapflights users on 6/24. 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.
Sun 9/207:00 am
SEA
- STL
1 stop6h 38m
United Airlines
Sat 9/269:00 am
STL
- SEA
2 stops14h 01m
United Airlines
Deal found 6/24![United Airlines logo]()
$384
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 9/2211:16 am
PDX
- STL
Nonstop3h 54m
Alaska Airlines
Wed 9/236:29 am
STL
- PDX
1 stop9h 08m
Alaska Airlines
Deal found 6/22![Alaska Airlines logo]()
$367
This Delta deal was found by Cheapflights users on 6/25. 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 9/215:15 pm
GEG
- STL
1 stop5h 29m
Delta
Thu 9/245:47 pm
STL
- GEG
1 stop7h 07m
Delta
Deal found 6/25![Delta logo]()
$413
This United 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/2211:03 am
SEA
- STL
2 stops8h 57m
United Airlines
Wed 9/239:43 am
STL
- SEA
1 stop8h 24m
United Airlines
Deal found 6/22![United Airlines logo]()
$384
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/2511:35 am
PDX
- STL
2 stops7h 35m
Southwest
Thu 8/276:15 pm
STL
- PDX
1 stop6h 50m
Southwest
Deal found 6/23![Southwest logo]()
$353
This Travelocity 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 Travelocity is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/166:00 pm
SEA
- STL
Nonstop3h 59m
Alaska Airlines
Tue 10/207:00 am
STL
- SEA
Nonstop4h 35m
Alaska Airlines
Deal found 6/21![Alaska Airlines logo]()
$377
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/145:30 am
GEG
- STL
1 stop6h 08m
Delta
Sat 8/226:20 am
STL
- GEG
1 stop8h 37m
Delta
Deal found 6/23![Delta logo]()
$415
This United Airlines deal was found by Cheapflights users on 6/25. 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 7/1011:49 pm
SEA
- STL
1 stop8h 18m
United Airlines
Tue 7/147:23 pm
STL
- SEA
1 stop7h 50m
United Airlines
Deal found 6/25![United Airlines logo]()
$393
This Alaska Airlines 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/2811:48 am
PDX
- STL
1 stop10h 11m
Alaska Airlines
Mon 8/316:08 pm
STL
- PDX
Nonstop4h 12m
Alaska Airlines
Deal found 6/23![Alaska Airlines logo]()
$387
This Southwest deal was found by Cheapflights users on 6/24. 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 7/227:30 am
SEA
- STL
2 stops9h 10m
Southwest
Sat 7/254:40 pm
STL
- SEA
2 stops9h 35m
Southwest
Deal found 6/24![Southwest logo]()
$397
This United Airlines 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/227:02 am
PDX
- STL
1 stop6h 36m
United Airlines
Wed 9/231:36 pm
STL
- PDX
2 stops9h 04m
United Airlines
Deal found 6/23![United Airlines logo]()
$424
This Alaska Airlines deal was found by Cheapflights users on 6/25. 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.
Mon 9/212:33 pm
GEG
- STL
1 stop7h 26m
Alaska Airlines
Sat 9/266:29 am
STL
- GEG
1 stop8h 10m
Alaska Airlines
Deal found 6/25![Alaska Airlines logo]()
$388
This Delta deal was found by Cheapflights users on 6/25. 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 8/125:24 pm
PSC
- STL
1 stop5h 17m
Delta
Sun 8/167:45 pm
STL
- PSC
1 stop5h 48m
Delta
Deal found 6/25![Delta logo]()
$471
This Kiwi.com deal was found by Cheapflights users on 6/25. 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 7/103:42 pm
BLI
- STL
1 stop24h 33m
Multiple Airlines
Tue 7/148:08 pm
STL
- BLI
2 stops40h 31m
Multiple Airlines
Deal found 6/25![Multiple Airlines logo]()
$579
This Southwest deal was found by Cheapflights users on 6/24. 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 8/285:00 am
PDX
- STL
2 stops11h 20m
Southwest
Sun 8/306:15 am
STL
- PDX
1 stop7h 05m
Southwest
Deal found 6/24![Southwest logo]()
$400
This Delta deal was found by Cheapflights users on 6/26. 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 8/267:15 am
PSC
- STL
1 stop7h 29m
Delta
Mon 8/315:00 pm
STL
- PSC
1 stop7h 15m
Delta
Deal found 6/26![Delta logo]()
$471
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.
Fri 10/166:35 am
SEA
- STL
2 stops10h 30m
Southwest
Tue 10/207:45 am
STL
- SEA
1 stop7h 05m
Southwest
Deal found 6/21![Southwest logo]()
$402
This 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 is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/15:52 am
GEG
- STL
1 stop6h 14m
Alaska Airlines
Tue 9/16:08 pm
STL
- GEG
1 stop7h 03m
Alaska Airlines
Deal found 6/21![Alaska Airlines logo]()
$403
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 8/255:52 am
GEG
- STL
1 stop6h 14m
Alaska Airlines
Wed 8/266:08 pm
STL
- GEG
1 stop7h 03m
Alaska Airlines
Deal found 6/22![Alaska Airlines logo]()
$403
This Delta deal was found by Cheapflights users on 6/26. 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.
Sat 7/117:05 am
PSC
- STL
1 stop6h 08m
Delta
Wed 7/157:55 pm
STL
- PSC
1 stop5h 59m
Delta
Deal found 6/26![Delta logo]()
$501
This Southwest deal was found by Cheapflights users on 6/26. 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 9/226:15 am
GEG
- STL
1 stop6h 50m
Southwest
Fri 9/253:45 pm
STL
- GEG
2 stops8h 15m
Southwest
Deal found 6/26![Southwest logo]()
$420
Last-minute flights from Washington to St. LouisDiscover last-minute flight deals from Washington to St. Louis. Data last updated June 27, 2026 and is based on user searches.
Discover last-minute flight deals from Washington to St. Louis. Data last updated June 27, 2026 and is based on user searches.
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.
Tue 6/305:20 pm
PDX
- STL
1 stop24h 03m
Frontier
Tue 7/78:08 pm
STL
- PDX
1 stop22h 28m
Frontier
Deal found 6/23![Frontier logo]()
$311
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.
Mon 7/65:49 pm
PDX
- STL
1 stop22h 16m
Frontier
Thu 7/98:08 pm
STL
- PDX
1 stop22h 43m
Frontier
Deal found 6/22![Frontier logo]()
$268
This CheapOair deal was found by Cheapflights users on 6/25. 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 7/105:49 pm
PDX
- STL
1 stop22h 26m
Frontier
Fri 7/178:08 pm
STL
- PDX
1 stop22h 43m
Frontier
Deal found 6/25![Frontier logo]()
$259
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.
Fri 7/105:49 pm
PDX
- STL
1 stop22h 26m
Frontier
Wed 7/158:08 pm
STL
- PDX
1 stop22h 43m
Frontier
Deal found 6/23![Frontier logo]()
$294
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.
Tue 7/145:16 pm
PDX
- STL
1 stop24h 07m
Frontier
Thu 7/167:10 pm
STL
- PDX
1 stop23h 44m
Frontier
Deal found 6/23![Frontier logo]()
$289
This CheapOair deal was found by Cheapflights users on 6/24. 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 7/145:16 pm
PDX
- STL
1 stop24h 07m
Frontier
Sat 7/188:08 pm
STL
- PDX
1 stop22h 43m
Frontier
Deal found 6/24![Frontier logo]()
$298
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.
Fri 7/175:49 pm
PDX
- STL
1 stop22h 26m
Frontier
Wed 7/228:08 pm
STL
- PDX
1 stop22h 43m
Frontier
Deal found 6/23![Frontier logo]()
$285
This CheapOair deal was found by Cheapflights users on 6/26. 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 7/215:16 pm
PDX
- STL
1 stop24h 07m
Frontier
Thu 7/237:10 pm
STL
- PDX
1 stop23h 44m
Frontier
Deal found 6/26![Frontier logo]()
$314
This American Airlines deal was found by Cheapflights users on 6/24. 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.
Mon 7/2711:15 pm
PDX
- STL
1 stop7h 16m
American Airlines
Fri 7/317:56 pm
STL
- PDX
1 stop6h 54m
American Airlines
Deal found 6/24![American Airlines logo]()
$319
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/295:15 am
PDX
- STL
1 stop6h 55m
Southwest
Tue 8/412:20 pm
STL
- PDX
2 stops9h 30m
Southwest
Deal found 6/23![Southwest logo]()
$324
This CheapOair deal was found by Cheapflights users on 6/24. 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 7/306:49 pm
PDX
- STL
1 stop21h 26m
Frontier
Fri 8/78:08 pm
STL
- PDX
1 stop22h 43m
Frontier
Deal found 6/24![Frontier logo]()
$250
This CheapOair deal was found by Cheapflights users on 6/24. 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 7/306:49 pm
PDX
- STL
1 stop21h 26m
Frontier
Tue 8/48:08 pm
STL
- PDX
1 stop22h 28m
Frontier
Deal found 6/24![Frontier logo]()
$315
One-way flights from Washington to St. LouisSearch for one-way flight options from Washington to St. Louis. Find affordable one-way fares based on user searches. Data last updated June 27, 2026.
Search for one-way flight options from Washington to St. Louis. Find affordable one-way fares based on user searches. Data last updated June 27, 2026.
This Frontier deal was found by Cheapflights users on 6/25. 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.
Mon 9/219:34 pm
PDX
- STL
1 stop12h 17m
Frontier
Deal found 6/25![Frontier logo]()
$126
This Trip.com 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/236:49 pm
PDX
- STL
1 stop21h 26m
Frontier
Deal found 6/23![Frontier logo]()
$129
This Trip.com deal was found by Cheapflights users on 6/25. 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 7/245:49 pm
PDX
- STL
1 stop22h 26m
Frontier
Deal found 6/25![Frontier logo]()
$130
This CheapOair deal was found by Cheapflights users on 6/24. 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 7/315:49 pm
PDX
- STL
1 stop22h 26m
Frontier
Deal found 6/24![Frontier logo]()
$131
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/205:49 pm
PDX
- STL
1 stop22h 16m
Frontier
Deal found 6/23![Frontier logo]()
$134
This Trip.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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/85:21 pm
PDX
- STL
1 stop24h 02m
Frontier
Deal found 6/22![Frontier logo]()
$139
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.
Fri 7/105:49 pm
PDX
- STL
1 stop22h 26m
Frontier
Deal found 6/22![Frontier logo]()
$140
This United 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/67:00 am
PDX
- STL
1 stop9h 39m
United Airlines
Deal found 6/22![United Airlines logo]()
$155
This Kiwi.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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/188:53 pm
SEA
- STL
1 stop18h 57m
Frontier
Deal found 6/22![Frontier logo]()
$156
This Super.com deal was found by Cheapflights users on 6/25. 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 7/127:06 pm
SEA
- STL
1 stop22h 17m
Frontier
Deal found 6/25![Frontier logo]()
$160
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/226:00 am
PDX
- STL
1 stop8h 47m
Delta
Deal found 6/23![Delta logo]()
$160
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.
Thu 7/308:53 pm
SEA
- STL
1 stop19h 22m
Frontier
Deal found 6/22![Frontier logo]()
$161
Find flight deals from Washington to St. Louis
Keep the following information in mind while searching for Washington to St. Louis flight deals. Data was last updated June 27, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $240 (Frontier) |
One-way from | $126 (Frontier) |
Popular in | December |
Cheapest in | January |
Average price | $491 |
Good round-trip deal | $437 or less |
Good one-way deal | $278 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Washington to St. Louis 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 27, 2026.
Use the filters below to find and compare flights from Washington to St. Louis that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
PortlandSt. Louis
PDX - STL
PDXSTL
Portland
Tue 8/25
7:16 am-3:38 pm
1 stop6h 22m
Lambert-St Louis
Thu 8/27
5:30 pm-10:52 pm
1 stop7h 22m
$319
PortlandSt. Louis
PDX - STL
PDXSTL
Portland
Sat 8/15
11:30 pm-9:15 am
1 stop7h 45m
Lambert-St Louis
Sun 8/23
7:30 pm-11:30 pm
1 stop6h 00m
$319
PortlandSt. Louis
PDX - STL
PDXSTL
Portland
Fri 7/24
9:20 pm-8:10 am
1 stop8h 50m
Lambert-St Louis
Fri 7/31
5:05 am-9:55 am
1 stop6h 50m
$319
PortlandSt. Louis
PDX - STL
PDXSTL
Portland
Wed 7/29
5:25 am-6:15 pm
2 stops10h 50m
Lambert-St Louis
Tue 8/4
12:20 pm-7:50 pm
2 stops9h 30m
$329
PortlandSt. Louis
PDX - STL
PDXSTL
Portland
Tue 8/25
11:35 am-9:10 pm
2 stops7h 35m
Lambert-St Louis
Thu 8/27
6:15 pm-11:05 pm
1 stop6h 50m
$353
SpokaneSt. Louis
GEG - STL
GEGSTL
Spokane
Tue 9/22
8:31 am-6:38 pm
1 stop8h 07m
Lambert-St Louis
Sat 9/26
6:29 am-11:37 am
1 stop7h 08m
$363
SpokaneSt. Louis
GEG - STL
GEGSTL
Spokane
Wed 9/23
5:52 am-2:21 pm
1 stop6h 29m
Lambert-St Louis
Sat 9/26
6:29 am-12:39 pm
1 stop8h 10m
$363
PortlandSt. Louis
PDX - STL
PDXSTL
Portland
Tue 9/22
11:16 am-5:10 pm
Nonstop3h 54m
Lambert-St Louis
Wed 9/23
6:29 am-1:37 pm
1 stop9h 08m
$367
Quickest round-trip
SeattleSt. Louis
SEA - STL
SEASTL
Seattle/Tacoma Intl
Fri 10/16
6:00 pm-11:59 pm
Nonstop3h 59m
Lambert-St Louis
Tue 10/20
7:00 am-9:35 am
Nonstop4h 35m
$377
SeattleSt. Louis
SEA - STL
SEASTL
Seattle/Tacoma Intl
Sun 9/20
7:00 am-3:38 pm
1 stop6h 38m
Lambert-St Louis
Sat 9/26
9:00 am-9:01 pm
2 stops14h 01m
$384
Showing 1-10 of 60 resultsSorted by cheapest first
Best time to book a flight from Washington to St. Louis
Have a flexible travel schedule? Discover the best time to fly to St. Louis from Washington with our price prediction graph.
PDX-STL
GEG-STL
SEA-STL
PSC-STL
BLI-STL
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 Washington to St. Louis
USWA-STL
PDX-STL
GEG-STL
SEA-STL
PSC-STL
What is the cheapest month to book a flight from State of Washington to St. Louis?
Currently, January is the cheapest month in which you can book a flight from State of Washington to St. Louis (average of $88). Flying from State of Washington to St. Louis in June is currently the most expensive (average of $202). 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 WA to STL?
Find hourly flight availability from Washington to St. Louis. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated June 27, 2026.
When flying from State of Washington to St. Louis, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.
Weekly flight availability from State of Washington to St. Louis
Explore weekly flight availability from Washington to St. Louis. 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 27, 2026.
The most flights from USWA to STL are scheduled on a Friday (11 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (5 on average).
How much does it cost to fly round-trip from State of Washington to St. Louis?
How far ahead should I book a flight from State of Washington to St. Louis?
Booking 76 days in advance of your planned departure date is, on average, the best time to get cheap flights from State of Washington to St. Louis. The general trend is that the closer you book to the departure date, the more expensive your flight will be.
Related info for your journey
Find useful and relevant information for your journey from Washington to St. Louis. 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 St. Louis?
Book flights to St. Louis if you plan to visit one of these locationsEdwardsville
O'Fallon
Fenton
Swansea
Fairview Heights
Eureka
Maryland Heights
Collinsville
Wentzville
Glencoe
Chesterfield
Alton
Farmington
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Complete your trip
Complete your trip to St. Louis by adding a car rental and/or hotel reservation to your travel itinerary.
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Find flights from Washington to St. Louis, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Washington and St. Louis flights
Browse other Washington and St. Louis flight options. Last updated on June 27, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Other flights to St. Louis
Explore flights to St. Louis departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on June 27, 2026.
Washington to St. Louis flights
Consider these flights traveling from Washington to St. Louis.
Top 7 airlines flying from Washington to St. Louis
Discover the top 7 airlines that operate flights from Washington to St. Louis. 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 27, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$104 | Average$379 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$137 | Average$227 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$157 | Average$402 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$182 | Average$444 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$188 | Average$526 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$204 | Average$403 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$226 | Average$513 | FlexibilityNo cancel fee | On-time75% |