$94+ 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 10/31. Fares are subject to change and may not be available on all flights or dates of travel.
STL — SEA
Sep 7 — Sep 141
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 August 8, 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 August 8, 2026.
This Kiwi.com deal was found by Cheapflights users on 8/3. 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.
Sun 9/131:02 pm -
1 stop24h 41m
Thu 9/2412:38 pm -
1 stop28h 39m
Deal found 8/3![Frontier logo]()
$231
This Kiwi.com deal was found by Cheapflights users on 8/3. 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.
Sun 9/131:02 pm -
1 stop24h 41m
Fri 9/1812:38 pm -
1 stop28h 39m
Deal found 8/3![Frontier logo]()
$239
This CheapOair deal was found by Cheapflights users on 8/7. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/912:17 pm -
1 stop25h 19m
Fri 9/1112:38 pm -
1 stop28h 39m
Deal found 8/7![Frontier logo]()
$240
This Trip.com deal was found by Cheapflights users on 8/4. 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 8/276:45 pm -
1 stop24h 36m
Mon 8/316:17 pm -
1 stop21h 33m
Deal found 8/4![Frontier logo]()
$244
This Kiwi.com deal was found by Cheapflights users on 8/3. 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.
Sat 9/128:10 pm -
1 stop17h 33m
Thu 9/2412:38 pm -
1 stop28h 39m
Deal found 8/3![Frontier logo]()
$252
This Trip.com deal was found by Cheapflights users on 8/7. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/912:17 pm -
1 stop25h 19m
Mon 9/1412:39 pm -
1 stop20h 53m
Deal found 8/7![Frontier logo]()
$253
This Frontier deal was found by Cheapflights users on 8/7. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/236:45 pm -
1 stop24h 36m
Thu 8/2712:20 pm -
1 stop28h 53m
Deal found 8/7![Frontier logo]()
$269
This Kiwi.com deal was found by Cheapflights users on 8/3. 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.
Sun 9/131:02 pm -
1 stop24h 41m
Sat 9/1912:24 pm -
2 stops26h 10m
Deal found 8/3![Frontier logo]()
$273
This CheapOair deal was found by Cheapflights users on 8/5. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/206:45 pm -
1 stop24h 36m
Mon 8/246:17 pm -
1 stop21h 33m
Deal found 8/5![Frontier logo]()
$278
This Kiwi.com deal was found by Cheapflights users on 8/3. 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 9/168:10 pm -
1 stop17h 33m
Fri 9/1812:38 pm -
1 stop28h 39m
Deal found 8/3![Frontier logo]()
$281
This Southwest deal was found by Cheapflights users on 8/7. 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.
Sat 9/122:25 pm -
2 stops10h 35m
Tue 9/2211:00 pm -
1 stop6h 50m
Deal found 8/7![Southwest logo]()
$293
This Kiwi.com deal was found by Cheapflights users on 8/7. 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.
Sun 9/131:02 pm -
1 stop28h 06m
Tue 9/224:27 pm -
1 stop24h 50m
Deal found 8/7![Frontier logo]()
$294
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 August 8, 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 August 8, 2026.
This Alaska Airlines deal was found by Cheapflights users on 8/7. 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 9/226:08 pm -
1 stop6h 31m
Wed 9/237:08 am -
1 stop8h 02m
Deal found 8/7![Alaska Airlines logo]()
$317
This Southwest deal was found by Cheapflights users on 8/4. 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 10/155:05 am -
1 stop6h 45m
Sat 10/172:40 pm -
1 stop6h 10m
Deal found 8/4![Southwest logo]()
$338
This Delta deal was found by Cheapflights users on 8/4. 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 10/297:00 pm -
1 stop6h 47m
Sun 11/15:35 am -
1 stop5h 57m
Deal found 8/4![Delta logo]()
$349
This United Airlines deal was found by Cheapflights users on 8/7. 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.
Sun 9/65:10 am -
2 stops8h 50m
Sun 9/135:00 am -
1 stop5h 40m
Deal found 8/7![United Airlines logo]()
$354
This American Airlines deal was found by Cheapflights users on 8/7. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/168:00 am -
1 stop8h 51m
Tue 9/225:05 am -
2 stops12h 02m
Deal found 8/7![American Airlines logo]()
$440
This Delta deal was found by Cheapflights users on 8/5. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/142:25 pm -
1 stop5h 51m
Fri 9/183:00 pm -
1 stop6h 16m
Deal found 8/5![Delta logo]()
$349
This Southwest deal was found by Cheapflights users on 8/6. 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.
Fri 9/116:25 pm -
1 stop8h 00m
Mon 9/1412:50 pm -
2 stops9h 50m
Deal found 8/6![Southwest logo]()
$356
This Alaska Airlines deal was found by Cheapflights users on 8/6. 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.
Tue 9/226:29 am -
Nonstop4h 27m
Tue 10/136:03 pm -
Nonstop3h 56m
Deal found 8/6![Alaska Airlines logo]()
$357
This Delta deal was found by Cheapflights users on 8/3. 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 9/125:00 pm -
1 stop7h 33m
Sat 9/199:51 am -
2 stops11h 25m
Deal found 8/3![Delta logo]()
$360
This Southwest deal was found by Cheapflights users on 8/4. 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 10/38:25 am -
2 stops10h 55m
Sat 10/1011:20 am -
2 stops9h 30m
Deal found 8/4![Southwest logo]()
$367
This Alaska Airlines deal was found by Cheapflights users on 8/4. 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 9/236:08 pm -
1 stop6h 31m
Sat 9/2612:35 pm -
Nonstop4h 03m
Deal found 8/4![Alaska Airlines logo]()
$367
This Alaska Airlines deal was found by Cheapflights users on 8/6. 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.
Sun 9/206:08 pm -
1 stop6h 31m
Thu 9/248:13 am -
Nonstop4h 08m
Deal found 8/6![Alaska Airlines logo]()
$372
This Southwest deal was found by Cheapflights users on 8/3. 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 10/15:50 pm -
2 stops8h 45m
Thu 10/811:35 am -
2 stops8h 10m
Deal found 8/3![Southwest logo]()
$377
This Delta deal was found by Cheapflights users on 8/8. 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.
Sat 10/1010:31 am -
2 stops14h 11m
Wed 10/149:55 am -
1 stop5h 49m
Deal found 8/8![Delta logo]()
$395
This Southwest deal was found by Cheapflights users on 8/7. 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 9/912:20 pm -
2 stops9h 35m
Fri 9/1110:45 pm -
2 stops12h 40m
Deal found 8/7![Southwest logo]()
$379
This Alaska Airlines deal was found by Cheapflights users on 8/7. 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.
Sun 9/63:02 pm -
1 stop6h 48m
Sat 9/125:07 am -
1 stop7h 14m
Deal found 8/7![Alaska Airlines logo]()
$382
This Delta deal was found by Cheapflights users on 8/3. 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 9/35:34 pm -
1 stop7h 35m
Thu 9/102:05 pm -
1 stop7h 11m
Deal found 8/3![Delta logo]()
$398
This Alaska Airlines deal was found by Cheapflights users on 8/3. 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 8/256:35 am -
Nonstop4h 27m
Wed 9/212:42 pm -
Nonstop3h 56m
Deal found 8/3![Alaska Airlines logo]()
$382
This Southwest deal was found by Cheapflights users on 8/5. 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.
Fri 9/46:15 pm -
1 stop6h 55m
Fri 9/1110:45 pm -
2 stops12h 40m
Deal found 8/5![Southwest logo]()
$389
This Delta deal was found by Cheapflights users on 8/3. 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 9/142:25 pm -
2 stops8h 50m
Mon 9/287:30 pm -
2 stops11h 10m
Deal found 8/3![Delta logo]()
$404
This Alaska Airlines deal was found by Cheapflights users on 8/3. 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 8/246:35 am -
Nonstop4h 27m
Wed 9/28:05 am -
Nonstop3h 59m
Deal found 8/3![Alaska Airlines logo]()
$382
This Southwest deal was found by Cheapflights users on 8/4. 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 9/146:25 am -
1 stop6h 50m
Fri 9/185:00 am -
2 stops11h 20m
Deal found 8/4![Southwest logo]()
$389
This Alaska Airlines deal was found by Cheapflights users on 8/6. 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.
Wed 9/26:35 am -
Nonstop4h 27m
Tue 9/88:13 am -
Nonstop4h 08m
Deal found 8/6![Alaska Airlines logo]()
$392
This Delta deal was found by Cheapflights users on 8/5. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/193:52 pm -
1 stop5h 49m
Tue 9/225:23 pm -
1 stop5h 21m
Deal found 8/5![Delta logo]()
$435
This Southwest deal was found by Cheapflights users on 8/7. 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.
Sun 8/239:55 pm -
Nonstop4h 10m
Thu 8/2712:20 pm -
1 stop8h 20m
Deal found 8/7![Southwest logo]()
$397
This Alaska Airlines deal was found by Cheapflights users on 8/4. 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 9/196:29 am -
Nonstop4h 27m
Mon 9/216:03 pm -
Nonstop3h 56m
Deal found 8/4![Alaska Airlines logo]()
$392
This Southwest deal was found by Cheapflights users on 8/5. 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 9/98:35 am -
1 stop6h 30m
Wed 9/2312:35 pm -
1 stop8h 15m
Deal found 8/5![Southwest logo]()
$398
This Delta deal was found by Cheapflights users on 8/5. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/166:15 am -
2 stops10h 30m
Tue 9/225:25 am -
2 stops10h 12m
Deal found 8/5![Delta logo]()
$443
This Alaska Airlines deal was found by Cheapflights users on 8/7. 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.
Wed 9/236:29 am -
Nonstop4h 27m
Sun 9/278:13 am -
Nonstop4h 08m
Deal found 8/7![Alaska Airlines logo]()
$392
This Southwest deal was found by Cheapflights users on 8/5. 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 9/98:35 am -
1 stop6h 30m
Wed 9/166:15 am -
2 stops9h 40m
Deal found 8/5![Southwest logo]()
$403
Last-minute flights from St. Louis to WashingtonDiscover last-minute flight deals from St. Louis to Washington. Data last updated August 8, 2026 and is based on user searches.
Discover last-minute flight deals from St. Louis to Washington. Data last updated August 8, 2026 and is based on user searches.
This CheapOair deal was found by Cheapflights users on 8/5. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/206:45 pm -
1 stop24h 36m
Mon 8/246:17 pm -
1 stop21h 33m
Deal found 8/5![Frontier logo]()
$278
This Frontier deal was found by Cheapflights users on 8/7. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/236:45 pm -
1 stop24h 36m
Thu 8/2712:20 pm -
1 stop28h 53m
Deal found 8/7![Frontier logo]()
$269
This Trip.com deal was found by Cheapflights users on 8/4. 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 8/276:45 pm -
1 stop24h 36m
Mon 8/316:17 pm -
1 stop21h 33m
Deal found 8/4![Frontier logo]()
$244
This CheapOair deal was found by Cheapflights users on 8/7. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/912:17 pm -
1 stop25h 19m
Fri 9/1112:38 pm -
1 stop28h 39m
Deal found 8/7![Frontier logo]()
$240
This Trip.com deal was found by Cheapflights users on 8/7. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/912:17 pm -
1 stop25h 19m
Mon 9/1412:39 pm -
1 stop20h 53m
Deal found 8/7![Frontier logo]()
$253
This Kiwi.com deal was found by Cheapflights users on 8/3. 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.
Sat 9/128:10 pm -
1 stop17h 33m
Thu 9/2412:38 pm -
1 stop28h 39m
Deal found 8/3![Frontier logo]()
$252
This Southwest deal was found by Cheapflights users on 8/7. 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.
Sat 9/122:25 pm -
2 stops10h 35m
Tue 9/2211:00 pm -
1 stop6h 50m
Deal found 8/7![Southwest logo]()
$293
This Kiwi.com deal was found by Cheapflights users on 8/3. 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.
Sun 9/131:02 pm -
1 stop24h 41m
Thu 9/2412:38 pm -
1 stop28h 39m
Deal found 8/3![Frontier logo]()
$231
This Kiwi.com deal was found by Cheapflights users on 8/3. 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.
Sun 9/131:02 pm -
1 stop24h 41m
Fri 9/1812:38 pm -
1 stop28h 39m
Deal found 8/3![Frontier logo]()
$239
This Kiwi.com deal was found by Cheapflights users on 8/3. 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.
Sun 9/131:02 pm -
1 stop24h 41m
Sat 9/1912:24 pm -
2 stops26h 10m
Deal found 8/3![Frontier logo]()
$273
This Kiwi.com deal was found by Cheapflights users on 8/7. 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.
Sun 9/131:02 pm -
1 stop28h 06m
Tue 9/224:27 pm -
1 stop24h 50m
Deal found 8/7![Frontier logo]()
$294
This Kiwi.com deal was found by Cheapflights users on 8/3. 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 9/168:10 pm -
1 stop17h 33m
Fri 9/1812:38 pm -
1 stop28h 39m
Deal found 8/3![Frontier logo]()
$281
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 August 8, 2026.
Search for one-way flight options from St. Louis to Washington. Find affordable one-way fares based on user searches. Data last updated August 8, 2026.
This American Airlines deal was found by Cheapflights users on 8/3. 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 10/2812:47 pm -
1 stop8h 57m
Deal found 8/3![American Airlines logo]()
$94
This Southwest deal was found by Cheapflights users on 8/3. 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 10/285:20 am -
2 stops10h 15m
Deal found 8/3![Southwest logo]()
$99
This Delta deal was found by Cheapflights users on 8/3. 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 9/68:00 am -
1 stop8h 50m
Deal found 8/3![Delta logo]()
$104
This Delta deal was found by Cheapflights users on 8/7. 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.
Sat 9/195:00 pm -
1 stop7h 10m
Deal found 8/7![Delta logo]()
$109
This Kiwi.com deal was found by Cheapflights users on 8/4. 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 10/208:10 pm -
1 stop22h 25m
Deal found 8/4![Frontier logo]()
$118
This Southwest deal was found by Cheapflights users on 8/6. 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 10/55:50 pm -
2 stops8h 45m
Deal found 8/6![Southwest logo]()
$119
This Trip.com deal was found by Cheapflights users on 8/5. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/317:58 pm -
1 stop23h 13m
Deal found 8/5![Frontier logo]()
$123
This Kiwi.com deal was found by Cheapflights users on 8/3. 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 9/308:10 pm -
1 stop17h 33m
Deal found 8/3![Frontier logo]()
$124
This CheapOair deal was found by Cheapflights users on 8/5. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/266:45 pm -
1 stop20h 07m
Deal found 8/5![Frontier logo]()
$126
This Kiwi.com deal was found by Cheapflights users on 8/5. 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.
Thu 8/277:58 pm -
1 stop15h 21m
Deal found 8/5![Frontier logo]()
$126
This Delta deal was found by Cheapflights users on 8/3. 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 10/97:00 pm -
1 stop6h 59m
Deal found 8/3![Delta logo]()
$130
This Kiwi.com deal was found by Cheapflights users on 8/4. 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 10/58:10 pm -
1 stop20h 58m
Deal found 8/4![Frontier logo]()
$134
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 August 8, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $231 (Kiwi.com) |
One-way from | $94 (American Airlines) |
Popular in | July |
Cheapest in | February |
Average price | $444 |
Good round-trip deal | $422 or less |
Good one-way deal | $278 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 August 8, 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. LouisSeattle
STL Lambert-St Louis - SEA Seattle/Tacoma Intl
STLSEA
Lambert-St Louis
Tue 9/22
6:08 pm-10:39 pm
1 stop6h 31m
Seattle/Tacoma Intl
Wed 9/23
7:08 am-5:10 pm
1 stop8h 02m
$317
St. LouisPortland
STL Lambert-St Louis - PDX Portland
STLPDX
Lambert-St Louis
Thu 10/15
5:05 am-9:50 am
1 stop6h 45m
Portland
Sat 10/17
2:40 pm-10:50 pm
1 stop6h 10m
$338
St. LouisPortland
STL Lambert-St Louis - PDX Portland
STLPDX
Lambert-St Louis
Thu 10/29
7:00 pm-11:47 pm
1 stop6h 47m
Portland
Sun 11/1
5:35 am-1:32 pm
1 stop5h 57m
$349
St. LouisPortland
STL Lambert-St Louis - PDX Portland
STLPDX
Lambert-St Louis
Mon 9/14
2:25 pm-6:16 pm
1 stop5h 51m
Portland
Fri 9/18
3:00 pm-11:16 pm
1 stop6h 16m
$349
St. LouisPortland
STL Lambert-St Louis - PDX Portland
STLPDX
Lambert-St Louis
Sun 9/6
5:10 am-12:00 pm
2 stops8h 50m
Portland
Sun 9/13
5:00 am-12:40 pm
1 stop5h 40m
$354
St. LouisSeattle
STL Lambert-St Louis - SEA Seattle/Tacoma Intl
STLSEA
Lambert-St Louis
Fri 9/11
6:25 pm-12:25 am
1 stop8h 00m
Seattle/Tacoma Intl
Mon 9/14
12:50 pm-12:40 am
2 stops9h 50m
$356
Quickest round-trip
St. LouisSeattle
STL Lambert-St Louis - SEA Seattle/Tacoma Intl
STLSEA
Lambert-St Louis
Tue 9/22
6:29 am-8:56 am
Nonstop4h 27m
Seattle/Tacoma Intl
Tue 10/13
6:03 pm-11:59 pm
Nonstop3h 56m
$357
St. LouisPortland
STL Lambert-St Louis - PDX Portland
STLPDX
Lambert-St Louis
Sat 9/12
5:00 pm-10:33 pm
1 stop7h 33m
Portland
Sat 9/19
9:51 am-11:16 pm
2 stops11h 25m
$360
St. LouisPortland
STL Lambert-St Louis - PDX Portland
STLPDX
Lambert-St Louis
Sat 10/3
8:25 am-5:20 pm
2 stops10h 55m
Portland
Sat 10/10
11:20 am-10:50 pm
2 stops9h 30m
$367
St. LouisSeattle
STL Lambert-St Louis - SEA Seattle/Tacoma Intl
STLSEA
Lambert-St Louis
Wed 9/23
6:08 pm-10:39 pm
1 stop6h 31m
Seattle/Tacoma Intl
Sat 9/26
12:35 pm-6:38 pm
Nonstop4h 03m
$367
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-SEA
STL-PSC
STL-GEG
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-SEA
STL-PSC
STL-GEG
What is the cheapest month to book a flight from St. Louis to State of Washington?
Currently, February is the cheapest month in which you can book a flight from St. Louis to State of Washington (average of $244). Flying from St. Louis to State of Washington in July is currently the most expensive (average of $513). 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 August 8, 2026.
Unlike at noon, when flights are generally more expensive, you can save up to 17% 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 August 8, 2026.
The most flights from STL to USWA are scheduled on a Thursday (10 on average). You will have fewer flight options on Sunday, which is when the least amount of flights are scheduled (6 on average).
How much does it cost to fly round-trip from St. Louis to State of Washington?
Airfare is below average for this route at the moment.
St. Louis to State of Washington flights typically cost between $372 and $529 in September.The cheapest round-trip price found within the last 5 days was $293 on Southwest (Sep 12-Sep 22).
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 43 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 August 8, 2026.
Travelers seeking maximum savings on their St. Louis to State of Washington flight should consider departing on Saturday 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 August 8, 2026.
Read through reviews of airlines operating flights from St. Louis to Washington, such as Southwest,Alaska Airlines, andDelta. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Entertainment
7.5
Boarding
8.1
Overall
8.0
Crew
8.6
Food
7.0
Comfort
8.0
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Entertainment
7.5
Boarding
8.1
Overall
8.0
Crew
8.6
Food
7.0
Comfort
8.0
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Entertainment
7.5
Boarding
8.1
Overall
8.0
Crew
8.6
Food
7.0
Comfort
8.0
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Entertainment
7.5
Boarding
8.1
Overall
8.0
Crew
8.6
Food
7.0
Comfort
8.0
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Entertainment
7.5
Boarding
8.1
Overall
8.0
Crew
8.6
Food
7.0
Comfort
8.0
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Entertainment
7.5
Boarding
8.1
Overall
8.0
Crew
8.6
Food
7.0
Comfort
8.0
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
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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Alternative routes for St. Louis to Washington
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St. Louis and Washington flights
Browse other St. Louis and Washington flight options. Last updated on August 8, 2026.
Popular flight searches
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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 August 8, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$129 | Average$266 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$134 | Average$406 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$191 | Average$430 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$192 | Average$416 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$193 | Average$440 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$218 | Average$503 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$237 | Average$329 | FlexibilityNo cancel fee | On-time85% |