$120+ Cheap flights from Illinois 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.
ORD — SEA
Jul 24 — Jul 311
Round-trip
1 adult, Economy
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Cheapest flights from Illinois to WashingtonExplore the most affordable flight options available from Illinois to Washington. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 24, 2026.
Explore the most affordable flight options available from Illinois to Washington. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 24, 2026.
This American 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/26:48 pm
PIA
- SEA
1 stop7h 11m
American Airlines
Wed 9/95:30 am
SEA
- PIA
1 stop8h 27m
American Airlines
Deal found 6/23![American Airlines logo]()
$271
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 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 Booking.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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/79:57 pm
ORD
- PDX
1 stop20h 39m
Frontier
Sat 7/1112:20 pm
PDX
- ORD
1 stop6h 32m
Frontier
Deal found 6/22![Frontier logo]()
$309
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.
Sat 8/158:30 am
STL
- PDX
Nonstop4h 10m
Southwest
Sat 8/2210:45 pm
PDX
- STL
1 stop11h 05m
Southwest
Deal found 6/23![Southwest logo]()
$309
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/277:15 am
ORD
- PDX
1 stop11h 39m
Frontier
Thu 8/66:49 pm
PDX
- ORD
1 stop8h 48m
Frontier
Deal found 6/21![Frontier logo]()
$310
This American 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/125:28 pm
PIA
- SEA
1 stop8h 43m
American Airlines
Mon 9/216:15 am
SEA
- PIA
1 stop8h 43m
American Airlines
Deal found 6/23![American Airlines logo]()
$310
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 7/39:48 pm
ORD
- PDX
1 stop21h 09m
Frontier
Sat 7/1112:20 pm
PDX
- ORD
1 stop6h 32m
Frontier
Deal found 6/23![Frontier logo]()
$311
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 7/37:38 pm
STL
- PDX
1 stop23h 19m
Frontier
Fri 7/105:49 pm
PDX
- STL
1 stop22h 26m
Frontier
Deal found 6/23![Frontier logo]()
$311
Best flights from Illinois to WashingtonDiscover carefully curated flight deals from Illinois to Washington that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated June 24, 2026.
Discover carefully curated flight deals from Illinois to Washington that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated June 24, 2026.
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.
Sat 8/158:30 am
STL
- PDX
Nonstop4h 10m
Southwest
Sat 8/2210:45 pm
PDX
- STL
1 stop11h 05m
Southwest
Deal found 6/23![Southwest logo]()
$309
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.
Sat 8/18:27 am
ORD
- GEG
1 stop6h 54m
Delta
Sat 8/85:15 am
GEG
- ORD
1 stop6h 08m
Delta
Deal found 6/22![Delta logo]()
$317
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.
Sat 8/88:20 pm
ORD
- PDX
1 stop13h 17m
Alaska Airlines
Sat 8/1510:59 pm
PDX
- ORD
Nonstop4h 01m
Alaska Airlines
Deal found 6/22![Alaska Airlines logo]()
$335
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.
Fri 7/171:30 pm
ORD
- PDX
Nonstop4h 27m
United Airlines
Sat 7/2510:40 pm
PDX
- ORD
Nonstop4h 05m
United Airlines
Deal found 6/22![United Airlines logo]()
$366
This Sun Country Air 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 Sun Country Air is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/237:25 am
ORD
- PDX
1 stop17h 18m
Sun Country Air
Wed 8/56:44 pm
PDX
- ORD
1 stop23h 15m
Sun Country Air
Deal found 6/23![Sun Country Air logo]()
$465
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 8/127:25 pm
MDW
- GEG
1 stop5h 44m
Delta
Sat 8/2212:36 pm
GEG
- MDW
1 stop8h 00m
Delta
Deal found 6/21![Delta logo]()
$317
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.
Tue 9/16:00 pm
MDW
- GEG
1 stop6h 25m
Southwest
Tue 9/84:55 pm
GEG
- MDW
1 stop10h 05m
Southwest
Deal found 6/21![Southwest logo]()
$317
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 7/287:59 pm
ORD
- PDX
1 stop15h 30m
Alaska Airlines
Tue 8/410:59 pm
PDX
- ORD
Nonstop4h 01m
Alaska Airlines
Deal found 6/22![Alaska Airlines logo]()
$335
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.
Fri 9/46:05 am
STL
- PDX
1 stop10h 55m
Southwest
Mon 9/710:45 pm
PDX
- STL
1 stop9h 20m
Southwest
Deal found 6/23![Southwest logo]()
$319
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 9/85:00 pm
STL
- PDX
1 stop7h 31m
Delta
Tue 9/155:10 pm
PDX
- STL
1 stop5h 34m
Delta
Deal found 6/23![Delta 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 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.
Sat 10/244:05 pm
PIA
- SEA
1 stop8h 51m
United Airlines
Tue 10/2711:03 pm
SEA
- PIA
1 stop9h 05m
United Airlines
Deal found 6/20![United Airlines logo]()
$371
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.
Tue 9/11:59 pm
ORD
- GEG
2 stops12h 00m
Delta
Tue 9/87:05 am
GEG
- ORD
1 stop8h 56m
Delta
Deal found 6/21![Delta logo]()
$322
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/294:35 pm
MDW
- GEG
2 stops9h 15m
Southwest
Wed 8/127:30 am
GEG
- MDW
2 stops9h 30m
Southwest
Deal found 6/20![Southwest logo]()
$327
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.
Thu 8/66:42 pm
ORD
- GEG
1 stop7h 17m
Alaska Airlines
Mon 8/107:45 pm
GEG
- ORD
1 stop8h 35m
Alaska Airlines
Deal found 6/21![Alaska Airlines logo]()
$338
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.
Mon 8/37:55 pm
ORD
- PDX
Nonstop4h 35m
United Airlines
Sun 8/911:40 pm
PDX
- ORD
Nonstop4h 05m
United Airlines
Deal found 6/22![United Airlines logo]()
$389
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.
Sun 8/309:55 pm
STL
- PDX
Nonstop4h 10m
Southwest
Sun 9/68:45 am
PDX
- STL
1 stop6h 15m
Southwest
Deal found 6/23![Southwest logo]()
$338
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.
Thu 8/65:56 pm
ORD
- GEG
1 stop8h 03m
Delta
Mon 8/1010:56 pm
GEG
- ORD
1 stop8h 27m
Delta
Deal found 6/19![Delta logo]()
$341
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 8/126:00 am
ORD
- SEA
Nonstop4h 38m
Alaska Airlines
Sun 8/237:40 am
SEA
- ORD
1 stop9h 41m
Alaska Airlines
Deal found 6/20![Alaska Airlines logo]()
$345
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 8/612:46 pm
MDW
- GEG
1 stop10h 44m
Delta
Mon 8/1010:56 pm
GEG
- MDW
1 stop9h 03m
Delta
Deal found 6/21![Delta logo]()
$341
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.
Tue 8/116:00 am
ORD
- SEA
Nonstop4h 38m
Alaska Airlines
Sun 8/238:48 am
SEA
- ORD
1 stop8h 33m
Alaska Airlines
Deal found 6/23![Alaska Airlines logo]()
$345
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/204:00 pm
MDW
- PDX
1 stop9h 05m
Southwest
Tue 8/2511:30 pm
PDX
- MDW
Nonstop3h 55m
Southwest
Deal found 6/19![Southwest logo]()
$348
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.
Wed 10/76:32 am
MLI
- SEA
1 stop6h 55m
United Airlines
Sat 10/1011:14 pm
SEA
- MLI
2 stops11h 23m
United Airlines
Deal found 6/19![United Airlines logo]()
$430
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.
Sat 8/158:02 am
ORD
- SEA
Nonstop4h 35m
Alaska Airlines
Sun 8/238:48 am
SEA
- ORD
1 stop8h 33m
Alaska Airlines
Deal found 6/23![Alaska Airlines logo]()
$345
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.
Thu 8/135:56 pm
ORD
- SEA
Nonstop4h 39m
Delta
Sun 8/165:35 pm
SEA
- ORD
Nonstop3h 54m
Delta
Deal found 6/19![Delta logo]()
$348
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 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 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.
Thu 8/136:42 pm
ORD
- SEA
Nonstop4h 52m
Alaska Airlines
Sun 8/165:48 pm
SEA
- ORD
Nonstop4h 11m
Alaska Airlines
Deal found 6/23![Alaska Airlines logo]()
$348
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/317:40 pm
ORD
- SEA
1 stop6h 21m
Delta
Tue 8/410:50 am
SEA
- ORD
Nonstop4h 08m
Delta
Deal found 6/20![Delta logo]()
$350
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.
Thu 8/64:55 pm
MDW
- SEA
1 stop9h 45m
Southwest
Fri 8/1411:25 am
SEA
- MDW
1 stop8h 50m
Southwest
Deal found 6/23![Southwest logo]()
$354
Last-minute flights from Illinois to WashingtonDiscover last-minute flight deals from Illinois to Washington. Data last updated June 24, 2026 and is based on user searches.
Discover last-minute flight deals from Illinois to Washington. Data last updated June 24, 2026 and is based on user searches.
This Priceline 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/17:20 am
ORD
- PDX
Nonstop4h 25m
Multiple Airlines
Fri 7/315:49 pm
PDX
- ORD
1 stop9h 48m
Multiple Airlines
Deal found 6/23![Multiple Airlines logo]()
$315
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 7/39:48 pm
ORD
- PDX
1 stop21h 09m
Frontier
Sat 7/1112:20 pm
PDX
- ORD
1 stop6h 32m
Frontier
Deal found 6/23![Frontier logo]()
$311
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 7/37:38 pm
STL
- PDX
1 stop23h 19m
Frontier
Fri 7/105:49 pm
PDX
- STL
1 stop22h 26m
Frontier
Deal found 6/23![Frontier logo]()
$311
This Expedia 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/39:13 pm
ORD
- PDX
1 stop16h 28m
Frontier
Mon 7/65:49 pm
PDX
- ORD
1 stop9h 48m
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.
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 Booking.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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/79:57 pm
ORD
- PDX
1 stop20h 39m
Frontier
Sat 7/1112:20 pm
PDX
- ORD
1 stop6h 32m
Frontier
Deal found 6/22![Frontier logo]()
$309
This Booking.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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/89:13 pm
ORD
- PDX
1 stop16h 22m
Multiple Airlines
Tue 7/1410:59 pm
PDX
- ORD
Nonstop4h 01m
Multiple Airlines
Deal found 6/23![Multiple Airlines logo]()
$313
This Booking.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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/89:57 pm
ORD
- PDX
1 stop20h 54m
Multiple Airlines
Wed 7/2210:59 pm
PDX
- ORD
Nonstop4h 01m
Multiple Airlines
Deal found 6/23![Multiple Airlines logo]()
$316
This Expedia 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/179:57 pm
ORD
- PDX
1 stop20h 54m
Multiple Airlines
Tue 7/2110:59 pm
PDX
- ORD
Nonstop4h 01m
Multiple Airlines
Deal found 6/23![Multiple Airlines 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 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 Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/277:15 am
ORD
- PDX
1 stop11h 39m
Frontier
Thu 8/66:49 pm
PDX
- ORD
1 stop8h 48m
Frontier
Deal found 6/21![Frontier logo]()
$310
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
One-way flights from Illinois to WashingtonSearch for one-way flight options from Illinois to Washington. Find affordable one-way fares based on user searches. Data last updated June 24, 2026.
Search for one-way flight options from Illinois to Washington. Find affordable one-way fares based on user searches. Data last updated June 24, 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.
Thu 9/1012:46 pm
STL
- PDX
1 stop9h 53m
Frontier
Deal found 6/24![Frontier logo]()
$120
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 6/21. 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.
Mon 7/207:10 pm
STL
- SEA
2 stops24h 41m
Frontier
Deal found 6/21![Frontier logo]()
$126
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 8/188:00 am
STL
- SEA
2 stops35h 51m
Frontier
Deal found 6/22![Frontier logo]()
$127
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 6/24. 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 7/237:10 pm
STL
- PDX
1 stop23h 44m
Frontier
Deal found 6/24![Frontier logo]()
$131
This Super.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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/78:08 pm
STL
- SEA
1 stop15h 09m
Frontier
Deal found 6/23![Frontier logo]()
$131
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.
Sat 7/118:08 pm
STL
- SEA
1 stop15h 09m
Frontier
Deal found 6/21![Frontier logo]()
$132
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.
Sat 8/88:08 pm
STL
- SEA
1 stop14h 56m
Frontier
Deal found 6/23![Frontier logo]()
$134
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.
Sat 8/17:10 pm
STL
- SEA
1 stop17h 29m
Frontier
Deal found 6/23![Frontier logo]()
$135
Find flight deals from Illinois to Washington
Keep the following information in mind while searching for Illinois to Washington flight deals. Data was last updated June 24, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $271 (American Airlines) |
One-way from | $120 (Priceline) |
Popular in | June |
Cheapest in | January |
Average price | $413 |
Good round-trip deal | $322 or less |
Good one-way deal | $177 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Illinois 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 24, 2026.
Use the filters below to find and compare flights from Illinois 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
Sat 8/15
8:30 am-10:40 am
Nonstop4h 10m
Portland
Sat 8/22
10:45 pm-11:50 am
1 stop11h 05m
$309
ChicagoSpokane
ORD - GEG
ORDGEG
Chicago O'Hare Intl
Sat 8/1
8:27 am-1:21 pm
1 stop6h 54m
Spokane
Sat 8/8
5:15 am-1:23 pm
1 stop6h 08m
$317
ChicagoSpokane
MDW - GEG
MDWGEG
Chicago Midway
Wed 8/12
7:25 pm-11:09 pm
1 stop5h 44m
Spokane
Sat 8/22
12:36 pm-10:36 pm
1 stop8h 00m
$317
ChicagoSpokane
MDW - GEG
MDWGEG
Chicago Midway
Tue 9/1
6:00 pm-10:25 pm
1 stop6h 25m
Spokane
Tue 9/8
4:55 pm-5:00 am
1 stop10h 05m
$317
St. LouisPortland
STL - PDX
STLPDX
Lambert-St Louis
Fri 9/4
6:05 am-3:00 pm
1 stop10h 55m
Portland
Mon 9/7
10:45 pm-10:05 am
1 stop9h 20m
$319
St. LouisPortland
STL - PDX
STLPDX
Lambert-St Louis
Tue 9/8
5:00 pm-10:31 pm
1 stop7h 31m
Portland
Tue 9/15
5:10 pm-12:44 am
1 stop5h 34m
$319
ChicagoSpokane
ORD - GEG
ORDGEG
Chicago O'Hare Intl
Tue 9/1
1:59 pm-11:59 pm
2 stops12h 00m
Spokane
Tue 9/8
7:05 am-6:01 pm
1 stop8h 56m
$322
ChicagoSpokane
MDW - GEG
MDWGEG
Chicago Midway
Wed 7/29
4:35 pm-11:50 pm
2 stops9h 15m
Spokane
Wed 8/12
7:30 am-7:00 pm
2 stops9h 30m
$327
ChicagoPortland
ORD - PDX
ORDPDX
Chicago O'Hare Intl
Sat 8/8
8:20 pm-7:37 am
1 stop13h 17m
Portland
Sat 8/15
10:59 pm-5:00 am
Nonstop4h 01m
$335
ChicagoPortland
ORD - PDX
ORDPDX
Chicago O'Hare Intl
Tue 7/28
7:59 pm-9:29 am
1 stop15h 30m
Portland
Tue 8/4
10:59 pm-5:00 am
Nonstop4h 01m
$335
Showing 1-10 of 60 resultsSorted by cheapest first
Best time to book a flight from Illinois to Washington
Have a flexible travel schedule? Discover the best time to fly to Washington from Illinois with our price prediction graph.
PIA-SEA
STL-PDX
ORD-PDX
STL-SEA
ORD-GEG
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 Illinois to Washington
USIL-USWA
PIA-SEA
STL-PDX
ORD-PDX
STL-SEA
What is the cheapest month to book a flight from Illinois to State of Washington?
Currently, October is the cheapest month in which you can book a flight from Illinois to State of Washington (average of $289). Flying from Illinois to State of Washington in January is currently the most expensive (average of $899). 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 IL to WA?
Find hourly flight availability from Illinois 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 24, 2026.
It’s typically best to fly out from Illinois to State of Washington at noon. Doing so could potentially save you 14% on the flight price compared to flying in the afternoon, which is usually more expensive.
Weekly flight availability from Illinois to State of Washington
Explore weekly flight availability from Illinois 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 24, 2026.
The most flights from USIL to USWA are scheduled on a Tuesday (57 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (14 on average).
How much does it cost to fly round-trip from Illinois to State of Washington?
How far ahead should I book a flight from Illinois to State of Washington?
The price you pay for your flight from Illinois to State of Washington may vary depending on when you book. For the best chance of a lower fare, look to book 63 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.
What is the cheapest day to fly from Illinois to State of Washington?
Use this chart to determine the cheapest time to fly round-trip from Illinois to Washington. Price data was last updated on June 20, 2026.
Travelers seeking maximum savings on their Illinois to State of Washington flight should consider departing on Monday evenings when fares are most often at their lowest. Sunday afternoons 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 24, 2026.
See what other customers who have flown with Alaska Airlines,Southwest, andDelta from Illinois to Washington have to say. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Crew
8.5
Food
7.0
Entertainment
7.0
Boarding
8.1
Overall
7.9
Comfort
7.8
Reviews
1 / 20
8.0
ExcellentAnonymous,Jun 2026
RDU - SEA
Crew
8.5
Food
7.0
Entertainment
7.0
Boarding
8.1
Overall
7.9
Comfort
7.8
Reviews
1 / 20
8.0
ExcellentAnonymous,Jun 2026
RDU - SEA
Crew
8.5
Food
7.0
Entertainment
7.0
Boarding
8.1
Overall
7.9
Comfort
7.8
Reviews
1 / 20
8.0
ExcellentAnonymous,Jun 2026
RDU - SEA
Crew
8.5
Food
7.0
Entertainment
7.0
Boarding
8.1
Overall
7.9
Comfort
7.8
Reviews
1 / 20
8.0
ExcellentAnonymous,Jun 2026
RDU - SEA
Crew
8.5
Food
7.0
Entertainment
7.0
Boarding
8.1
Overall
7.9
Comfort
7.8
Reviews
1 / 20
8.0
ExcellentAnonymous,Jun 2026
RDU - SEA
Crew
8.5
Food
7.0
Entertainment
7.0
Boarding
8.1
Overall
7.9
Comfort
7.8
Reviews
1 / 20
8.0
ExcellentAnonymous,Jun 2026
RDU - SEA
Related info for your journey
Find useful and relevant information for your journey from Illinois 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 Illinois to Washington
See prices for flight routes from nearby airports that may be better suited for you.
Complete your trip
Complete your trip to Washington by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Illinois to Washington by cabin class
Find flights from Illinois to Washington, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Illinois and Washington flights
Browse other Illinois and Washington flight options. Last updated on June 24, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Find a return flight route from Washington
Find the right flight back to Illinois after your stay in Washington
Illinois to Washington flights
Consider these flights traveling from Illinois to Washington.
Top 7 airlines flying from Illinois to Washington
Discover the top 7 airlines that operate flights from Illinois 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 24, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$89 | Average$275 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$125 | Average$390 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$131 | Average$258 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$177 | Average$395 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$177 | Average$475 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$177 | Average$543 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$194 | Average$358 | FlexibilityNo cancel fee | On-time63% |