$77+ Cheap flights from Washington to Illinois
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 9/9. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — ORD
Sep 11 — Sep 181
Round-trip
1 adult, Economy
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Cheapest flights from Washington to IllinoisExplore the most affordable flight options available from Washington to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 12, 2026.
Explore the most affordable flight options available from Washington to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 12, 2026.
This CheapOair deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” 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 10/129:34 pm -
1 stop25h 43m
Mon 10/198:10 pm -
1 stop22h 25m
Deal found 8/11![Frontier logo]()
$174
This Alaska Airlines deal was found by Cheapflights users on 8/12. Clicking the “Pick Dates” 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 12/42:13 pm -
Nonstop3h 54m
Sat 12/59:20 am -
1 stop16h 27m
Deal found 8/12![Alaska Airlines logo]()
$189
This Kiwi.com deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” 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 10/812:34 pm -
1 stop28h 41m
Wed 10/148:10 pm -
1 stop22h 25m
Deal found 8/11![Frontier logo]()
$215
This CheapOair deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/215:35 pm -
1 stop23h 40m
Sun 10/255:19 pm -
1 stop29h 20m
Deal found 8/11![Frontier logo]()
$226
This American Airlines deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” 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 9/27:39 am -
1 stop7h 02m
Sat 9/195:18 pm -
1 stop8h 49m
Deal found 8/11![American Airlines logo]()
$229
This Southwest deal was found by Cheapflights users on 8/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/111:35 pm -
1 stop7h 25m
Tue 10/64:05 pm -
1 stop9h 00m
Deal found 8/9![Southwest logo]()
$230
This Southwest deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” 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 10/87:35 pm -
1 stop11h 15m
Mon 10/125:10 am -
1 stop6h 25m
Deal found 8/11![Southwest logo]()
$234
This Southwest deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” 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 10/172:40 pm -
1 stop6h 10m
Mon 10/195:10 am -
2 stops9h 25m
Deal found 8/11![Southwest logo]()
$235
This Delta deal was found by Cheapflights users on 8/12. Clicking the “Pick Dates” 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 12/11:40 pm -
1 stop6h 07m
Tue 12/157:35 am -
1 stop6h 54m
Deal found 8/12![Delta logo]()
$239
This CheapOair deal was found by Cheapflights users on 8/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/239:34 pm -
1 stop25h 43m
Wed 10/285:32 pm -
1 stop28h 36m
Deal found 8/9![Frontier logo]()
$240
This Delta deal was found by Cheapflights users on 8/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/167:30 pm -
2 stops11h 37m
Sat 9/192:00 pm -
1 stop7h 32m
Deal found 8/10![Delta logo]()
$244
This Kiwi.com deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” 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 10/1012:34 pm -
2 stops19h 06m
Wed 10/148:10 pm -
1 stop22h 25m
Deal found 8/11![Frontier logo]()
$244
Best flights from Washington to IllinoisDiscover carefully curated flight deals from Washington to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated August 12, 2026.
Discover carefully curated flight deals from Washington to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated August 12, 2026.
This United Airlines deal was found by Cheapflights users on 8/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/92:27 pm -
1 stop6h 32m
Wed 9/164:40 pm -
1 stop8h 13m
Deal found 8/12![United Airlines logo]()
$229
This Southwest deal was found by Cheapflights users on 8/12. Clicking the “Pick Dates” 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 9/231:05 pm -
1 stop7h 45m
Tue 9/295:35 am -
2 stops11h 50m
Deal found 8/12![Southwest logo]()
$240
This Delta deal was found by Cheapflights users on 8/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/63:22 pm -
1 stop5h 59m
Mon 11/95:30 pm -
1 stop8h 29m
Deal found 8/10![Delta logo]()
$259
This Alaska Airlines deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” 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 9/228:41 am -
1 stop8h 40m
Sat 9/262:18 pm -
1 stop9h 22m
Deal found 8/11![Alaska Airlines logo]()
$317
This JetBlue 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 JetBlue is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/229:40 pm -
1 stop10h 18m
Fri 10/210:59 am -
1 stop11h 45m
Deal found 8/7![JetBlue logo]()
$389
This American Airlines 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/2811:48 am -
1 stop9h 31m
Sun 8/304:43 pm -
1 stop10h 07m
Deal found 8/8![American Airlines logo]()
$394
This Delta deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” 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 11/177:43 pm -
2 stops10h 03m
Thu 12/1012:58 pm -
1 stop8h 05m
Deal found 8/11![Delta logo]()
$262
This Southwest deal was found by Cheapflights users on 8/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/2812:05 pm -
2 stops8h 00m
Wed 11/45:30 am -
2 stops9h 30m
Deal found 8/10![Southwest logo]()
$263
This United Airlines deal was found by Cheapflights users on 8/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/11:37 pm -
1 stop6h 22m
Sat 9/59:15 am -
Nonstop4h 23m
Deal found 8/10![United Airlines logo]()
$265
This Delta deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” 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 9/312:36 pm -
1 stop9h 21m
Sat 9/512:54 pm -
1 stop8h 38m
Deal found 8/11![Delta logo]()
$282
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.
Sat 10/317:20 am -
1 stop9h 00m
Tue 11/36:33 pm -
1 stop7h 26m
Deal found 8/7![Alaska Airlines logo]()
$331
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.
Thu 11/511:20 am -
2 stops11h 30m
Sun 11/85:05 am -
2 stops10h 50m
Deal found 8/7![Southwest logo]()
$323
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.
Sat 10/1011:59 pm -
1 stop8h 11m
Wed 10/148:00 am -
2 stops14h 37m
Deal found 8/7![United Airlines logo]()
$332
This Alaska Airlines deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” 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 9/612:16 am -
Nonstop4h 04m
Sat 9/196:00 am -
Nonstop4h 30m
Deal found 8/11![Alaska Airlines logo]()
$337
This Delta deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” 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 9/2511:45 am -
Nonstop4h 16m
Fri 10/27:00 am -
Nonstop4h 35m
Deal found 8/11![Delta logo]()
$307
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.
Thu 9/36:30 am -
2 stops8h 35m
Sun 9/611:10 am -
Nonstop3h 45m
Deal found 8/7![Southwest logo]()
$329
This United Airlines deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/1611:00 pm -
Nonstop4h 06m
Sun 9/204:29 pm -
Nonstop4h 45m
Deal found 8/11![United Airlines logo]()
$333
This Delta deal was found by Cheapflights users on 8/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/56:00 am -
1 stop6h 45m
Thu 11/127:00 pm -
1 stop6h 57m
Deal found 8/10![Delta logo]()
$313
This Alaska Airlines deal was found by Cheapflights users on 8/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/167:09 am -
1 stop9h 29m
Tue 9/226:08 pm -
Nonstop4h 12m
Deal found 8/10![Alaska Airlines logo]()
$347
This Southwest deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” 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 10/187:50 pm -
1 stop8h 00m
Wed 10/216:05 am -
1 stop6h 10m
Deal found 8/11![Southwest logo]()
$332
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.
Thu 10/2210:43 am -
Nonstop4h 15m
Sun 10/257:45 pm -
Nonstop4h 42m
Deal found 8/7![United Airlines logo]()
$357
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.
Sat 10/107:09 am -
1 stop6h 35m
Tue 10/137:02 am -
1 stop8h 22m
Deal found 8/7![Alaska Airlines logo]()
$357
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 9/55:30 am -
2 stops9h 29m
Fri 9/119:59 am -
2 stops8h 22m
Deal found 8/8![Delta logo]()
$327
This Southwest deal was found by Cheapflights users on 8/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/286:15 am -
Nonstop3h 50m
Sat 10/3111:00 am -
Nonstop4h 25m
Deal found 8/10![Southwest logo]()
$333
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.
Mon 9/2111:02 pm -
Nonstop4h 01m
Fri 9/254:20 pm -
Nonstop4h 33m
Deal found 8/7![United Airlines logo]()
$357
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.
Tue 12/15:22 pm -
1 stop5h 08m
Tue 12/87:00 pm -
1 stop6h 53m
Deal found 8/7![Delta logo]()
$337
This Southwest deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/1011:30 pm -
Nonstop3h 55m
Sun 9/139:20 pm -
Nonstop4h 15m
Deal found 8/11![Southwest logo]()
$341
This Alaska Airlines deal was found by Cheapflights users on 8/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/68:33 am -
Nonstop4h 14m
Sun 9/136:00 am -
Nonstop4h 30m
Deal found 8/10![Alaska Airlines logo]()
$383
This United Airlines deal was found by Cheapflights users on 8/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/811:00 pm -
1 stop9h 07m
Tue 9/152:05 pm -
1 stop7h 10m
Deal found 8/10![United Airlines logo]()
$359
This Southwest deal was found by Cheapflights users on 8/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/266:25 am -
2 stops10h 05m
Tue 12/14:40 pm -
1 stop8h 40m
Deal found 8/10![Southwest logo]()
$341
Last-minute flights from Washington to IllinoisDiscover last-minute flight deals from Washington to Illinois. Data last updated August 12, 2026 and is based on user searches.
Discover last-minute flight deals from Washington to Illinois. Data last updated August 12, 2026 and is based on user searches.
This CheapOair deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” 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 8/262:37 pm -
1 stop26h 36m
Tue 9/86:45 pm -
1 stop16h 57m
Deal found 8/11![Frontier logo]()
$261
This CheapOair deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” 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 8/2712:20 pm -
1 stop28h 53m
Mon 8/317:58 pm -
1 stop23h 13m
Deal found 8/11![Frontier logo]()
$226
This American Airlines deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” 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 9/27:39 am -
1 stop7h 02m
Sat 9/195:18 pm -
1 stop8h 49m
Deal found 8/11![American Airlines logo]()
$229
This Southwest deal was found by Cheapflights users on 8/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/512:45 pm -
1 stop6h 05m
Sat 9/125:40 am -
1 stop7h 05m
Deal found 8/10![Southwest logo]()
$251
This Southwest deal was found by Cheapflights users on 8/12. Clicking the “Pick Dates” 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 9/51:40 pm -
1 stop6h 40m
Mon 9/78:50 pm -
Nonstop3h 55m
Deal found 8/12![Southwest logo]()
$259
This Delta deal was found by Cheapflights users on 8/12. Clicking the “Pick Dates” 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 9/95:10 am -
1 stop6h 19m
Wed 9/165:44 pm -
1 stop8h 15m
Deal found 8/12![Delta logo]()
$257
This United Airlines deal was found by Cheapflights users on 8/12. Clicking the “Pick Dates” 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 9/117:02 am -
1 stop8h 04m
Tue 9/151:36 pm -
1 stop6h 33m
Deal found 8/12![United Airlines logo]()
$254
This Southwest deal was found by Cheapflights users on 8/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/111:30 pm -
1 stop7h 45m
Mon 9/146:15 pm -
1 stop6h 55m
Deal found 8/9![Southwest logo]()
$259
This Delta deal was found by Cheapflights users on 8/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/127:05 am -
1 stop8h 55m
Sat 9/197:00 am -
1 stop7h 20m
Deal found 8/10![Delta logo]()
$239
This Delta deal was found by Cheapflights users on 8/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/167:30 pm -
2 stops11h 37m
Sat 9/192:00 pm -
1 stop7h 32m
Deal found 8/10![Delta logo]()
$244
This Delta deal was found by Cheapflights users on 8/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/165:10 am -
2 stops10h 54m
Sat 9/1912:29 pm -
2 stops11h 26m
Deal found 8/10![Delta logo]()
$249
This Southwest deal was found by Cheapflights users on 8/12. Clicking the “Pick Dates” 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 9/231:05 pm -
1 stop7h 45m
Tue 9/295:35 am -
2 stops11h 50m
Deal found 8/12![Southwest logo]()
$240
One-way flights from Washington to IllinoisSearch for one-way flight options from Washington to Illinois. Find affordable one-way fares based on user searches. Data last updated August 12, 2026.
Search for one-way flight options from Washington to Illinois. Find affordable one-way fares based on user searches. Data last updated August 12, 2026.
This Super.com deal was found by Cheapflights users on 8/12. Clicking the “Pick Dates” 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.
Wed 9/99:45 pm -
1 stop11h 32m
Deal found 8/12![Frontier logo]()
$77
This Frontier deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” 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.
Sat 9/129:45 pm -
1 stop11h 32m
Deal found 8/11![Frontier logo]()
$78
This Kiwi.com deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” 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 9/154:27 pm -
1 stop24h 50m
Deal found 8/11![Frontier logo]()
$80
This Jetabroad deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Jetabroad is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/109:16 pm -
1 stop23h 23m
Deal found 8/11![Frontier logo]()
$81
This Kiwi.com deal was found by Cheapflights users on 8/12. Clicking the “Pick Dates” 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 10/97:41 pm -
1 stop21h 16m
Deal found 8/12![Frontier logo]()
$83
This Kiwi.com deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” 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 9/104:27 pm -
1 stop24h 50m
Deal found 8/11![Frontier logo]()
$85
This Kiwi.com deal was found by Cheapflights users on 8/12. Clicking the “Pick Dates” 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 11/99:16 pm -
1 stop23h 23m
Deal found 8/12![Frontier logo]()
$89
This CheapOair deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” 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 9/1012:38 pm -
1 stop28h 39m
Deal found 8/11![Frontier logo]()
$89
This Kiwi.com deal was found by Cheapflights users on 8/12. Clicking the “Pick Dates” 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 10/89:16 pm -
1 stop26h 01m
Deal found 8/12![Frontier logo]()
$91
This Southwest deal was found by Cheapflights users on 8/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/94:15 pm -
1 stop5h 30m
Deal found 8/10![Southwest logo]()
$92
This CheapOair deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” 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 10/199:34 pm -
1 stop25h 43m
Deal found 8/11![Frontier logo]()
$93
This Southwest deal was found by Cheapflights users on 8/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/1012:50 pm -
2 stops9h 50m
Deal found 8/11![Southwest logo]()
$97
Find flight deals from Washington to Illinois
Keep the following information in mind while searching for Washington to Illinois flight deals. Data was last updated August 12, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $174 (CheapOair) |
One-way from | $77 (Super.com) |
Popular in | June |
Cheapest in | February |
Average price | $369 |
Good round-trip deal | $365 or less |
Good one-way deal | $208 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Washington to Illinois 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 12, 2026.
Use the filters below to find and compare flights from Washington to Illinois that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
PortlandSt. Louis
PDX Portland - STL Lambert-St Louis
PDXSTL
Portland
Wed 9/9
2:27 pm-10:59 pm
1 stop6h 32m
Lambert-St Louis
Wed 9/16
4:40 pm-10:53 pm
1 stop8h 13m
$229
PortlandSt. Louis
PDX Portland - STL Lambert-St Louis
PDXSTL
Portland
Wed 9/23
1:05 pm-10:50 pm
1 stop7h 45m
Lambert-St Louis
Tue 9/29
5:35 am-3:25 pm
2 stops11h 50m
$240
PortlandSt. Louis
PDX Portland - STL Lambert-St Louis
PDXSTL
Portland
Fri 11/6
3:22 pm-11:21 pm
1 stop5h 59m
Lambert-St Louis
Mon 11/9
5:30 pm-11:59 pm
1 stop8h 29m
$259
SpokaneChicago
GEG Spokane - ORD Chicago O'Hare Intl
GEGORD
Spokane
Tue 11/17
7:43 pm-7:46 am
2 stops10h 03m
Chicago O'Hare Intl
Thu 12/10
12:58 pm-7:03 pm
1 stop8h 05m
$262
SeattleSt. Louis
SEA Seattle/Tacoma Intl - STL Lambert-St Louis
SEASTL
Seattle/Tacoma Intl
Wed 10/28
12:05 pm-10:05 pm
2 stops8h 00m
Lambert-St Louis
Wed 11/4
5:30 am-1:00 pm
2 stops9h 30m
$263
SpokaneChicago
GEG Spokane - ORD Chicago O'Hare Intl
GEGORD
Spokane
Tue 9/1
1:37 pm-9:59 pm
1 stop6h 22m
Chicago O'Hare Intl
Sat 9/5
9:15 am-11:38 am
Nonstop4h 23m
$265
SpokaneChicago
GEG Spokane - ORD Chicago O'Hare Intl
GEGORD
Spokane
Thu 9/3
12:36 pm-11:57 pm
1 stop9h 21m
Chicago O'Hare Intl
Sat 9/5
12:54 pm-7:32 pm
1 stop8h 38m
$282
SeattleChicago
SEA Seattle/Tacoma Intl - ORD Chicago O'Hare Intl
SEAORD
Seattle/Tacoma Intl
Fri 9/25
11:45 am-6:01 pm
Nonstop4h 16m
Chicago O'Hare Intl
Fri 10/2
7:00 am-9:35 am
Nonstop4h 35m
$307
SeattleSt. Louis
SEA Seattle/Tacoma Intl - STL Lambert-St Louis
SEASTL
Seattle/Tacoma Intl
Thu 11/5
6:00 am-2:45 pm
1 stop6h 45m
Lambert-St Louis
Thu 11/12
7:00 pm-11:57 pm
1 stop6h 57m
$313
SeattleChicago
SEA Seattle/Tacoma Intl - ORD Chicago O'Hare Intl
SEAORD
Seattle/Tacoma Intl
Tue 9/22
8:41 am-7:21 pm
1 stop8h 40m
Chicago O'Hare Intl
Sat 9/26
2:18 pm-9:40 pm
1 stop9h 22m
$317
Showing 1-10 of 60 resultsSorted by cheapest first
Best time to book a flight from Washington to Illinois
Have a flexible travel schedule? Discover the best time to fly to Illinois from Washington with our price prediction graph.
SEA-STL
PDX-STL
GEG-ORD
GEG-MDW
SEA-MLI
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 Illinois
USWA-USIL
SEA-STL
PDX-STL
GEG-ORD
GEG-MDW
What is the cheapest month to book a flight from State of Washington to Illinois?
Currently, February is the cheapest month in which you can book a flight from State of Washington to Illinois (average of $275). Flying from State of Washington to Illinois in June is currently the most expensive (average of $421). 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 IL?
Find hourly flight availability from Washington to Illinois. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated August 12, 2026.
When flying from State of Washington to Illinois, the time of day you fly usually plays a role in the price. Save by searching for a flight at noon, which can drop the price by up to 27% versus a flight in the evening.
Weekly flight availability from State of Washington to Illinois
Explore weekly flight availability from Washington to Illinois. 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 12, 2026.
The most flights from USWA to USIL are scheduled on a Monday (61 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (27 on average).
How much does it cost to fly round-trip from State of Washington to Illinois?
Airfare is below average for this route at the moment.
State of Washington to Illinois flights typically cost between $311 and $475 in November.The cheapest round-trip price found within the last 5 days was $281 on Frontier (Nov 6-Nov 8).
How far ahead should I book a flight from State of Washington to Illinois?
To ensure you get the cheapest price possible for a flight from State of Washington to Illinois, you should look to book at least 60 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 State of Washington to Illinois?
Use this chart to determine the cheapest time to fly round-trip from Washington to Illinois. Price data was last updated on August 8, 2026.
Travelers seeking maximum savings on their State of Washington to Illinois flight should consider departing on Tuesday at noon when fares are most often at their lowest. Monday mornings flights should be avoided if possible as fares are typically the most expensive at this time.
Reviews of airlines servicing Illinois
Get insights into the airlines that provide service to Illinois. 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 Illinois. Reviews last updated August 12, 2026.
Get a feel of what it's like to fly with Southwest,Alaska Airlines, andDelta from Washington to Illinois by reading reviews from past customers. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Boarding
8.1
Crew
8.6
Food
7.0
Overall
8.0
Entertainment
7.5
Comfort
8.0
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Boarding
8.1
Crew
8.6
Food
7.0
Overall
8.0
Entertainment
7.5
Comfort
8.0
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Boarding
8.1
Crew
8.6
Food
7.0
Overall
8.0
Entertainment
7.5
Comfort
8.0
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Boarding
8.1
Crew
8.6
Food
7.0
Overall
8.0
Entertainment
7.5
Comfort
8.0
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Boarding
8.1
Crew
8.6
Food
7.0
Overall
8.0
Entertainment
7.5
Comfort
8.0
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Boarding
8.1
Crew
8.6
Food
7.0
Overall
8.0
Entertainment
7.5
Comfort
8.0
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Related info for your journey
Find useful and relevant information for your journey from Washington to Illinois. 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 Washington to Illinois
See prices for flight routes from nearby airports that may be better suited for you.
Complete your trip
Complete your trip to Illinois by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Washington to Illinois by cabin class
Find flights from Washington to Illinois, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Washington and Illinois flights
Browse other Washington and Illinois flight options. Last updated on August 12, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Find a return flight route from Illinois
Find the right flight back to Washington after your stay in Illinois
Washington to Illinois flights
Consider these flights traveling from Washington to Illinois.
Top 6 airlines flying from Washington to Illinois
Discover the top 6 airlines that operate flights from Washington to Illinois. 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 12, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$137 | Average$404 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$177 | Average$450 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$182 | Average$421 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$184 | Average$435 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$193 | Average$310 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$239 | Average$421 | FlexibilityNo cancel fee | On-time63% |