$104+ Cheap flights from Oregon 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 12/8. Fares are subject to change and may not be available on all flights or dates of travel.
PDX — ORD
Jul 15 — Jul 221
Round-trip
1 adult, Economy
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Find cheap flights from Oregon to Illinois with Cheapflights
1. Tell us where you want to go
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Cheapest flights from Oregon to IllinoisExplore the most affordable flight options available from Oregon to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 15, 2026.
Explore the most affordable flight options available from Oregon to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 15, 2026.
This Delta deal was found by Cheapflights users on 6/10. 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.
Tue 12/86:15 am
PDX
- STL
1 stop6h 16m
Delta
Tue 12/155:30 pm
STL
- PDX
1 stop8h 17m
Delta
Deal found 6/10![Delta logo]()
$211
This Southwest deal was found by Cheapflights users on 6/11. 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.
Wed 9/211:30 pm
PDX
- STL
1 stop9h 00m
Southwest
Sat 9/58:30 am
STL
- PDX
Nonstop4h 10m
Southwest
Deal found 6/11![Southwest logo]()
$222
This Delta deal was found by Cheapflights users on 6/10. 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 12/93:10 pm
PDX
- STL
1 stop6h 08m
Delta
Wed 12/167:55 pm
STL
- PDX
1 stop5h 56m
Delta
Deal found 6/10![Delta logo]()
$231
This American Airlines deal was found by Cheapflights users on 6/11. 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.
Tue 9/16:27 am
PDX
- STL
1 stop9h 38m
American Airlines
Fri 9/115:00 am
STL
- PDX
1 stop7h 55m
American Airlines
Deal found 6/11![American Airlines logo]()
$251
This Southwest deal was found by Cheapflights users on 6/11. 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 9/311:30 pm
PDX
- STL
1 stop9h 00m
Southwest
Mon 9/76:05 am
STL
- PDX
1 stop10h 55m
Southwest
Deal found 6/11![Southwest logo]()
$252
This Southwest deal was found by Cheapflights users on 6/11. 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.
Tue 12/86:55 am
PDX
- STL
2 stops8h 25m
Southwest
Tue 12/151:50 pm
STL
- PDX
2 stops9h 30m
Southwest
Deal found 6/11![Southwest logo]()
$257
This Southwest deal was found by Cheapflights users on 6/10. 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 12/911:40 am
PDX
- STL
1 stop6h 05m
Southwest
Tue 12/158:25 am
STL
- PDX
2 stops8h 35m
Southwest
Deal found 6/10![Southwest logo]()
$264
This Southwest deal was found by Cheapflights users on 6/10. 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 12/911:40 am
PDX
- STL
2 stops8h 15m
Southwest
Wed 12/161:50 pm
STL
- PDX
2 stops9h 30m
Southwest
Deal found 6/10![Southwest logo]()
$269
This United Airlines deal was found by Cheapflights users on 6/10. 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.
Fri 8/2810:50 am
PDX
- STL
1 stop7h 56m
United Airlines
Mon 8/315:10 am
STL
- PDX
1 stop6h 22m
United Airlines
Deal found 6/10![United Airlines logo]()
$271
This CheapOair deal was found by Cheapflights users on 6/12. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/295:21 pm
PDX
- STL
1 stop24h 02m
Frontier
Tue 8/48:08 pm
STL
- PDX
1 stop22h 28m
Frontier
Deal found 6/12![Frontier logo]()
$275
This Southwest deal was found by Cheapflights users on 6/11. 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 9/103:25 pm
PDX
- STL
1 stop6h 25m
Southwest
Sun 9/139:55 pm
STL
- PDX
Nonstop4h 10m
Southwest
Deal found 6/11![Southwest logo]()
$276
This Southwest deal was found by Cheapflights users on 6/11. 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.
Mon 8/3112:20 pm
EUG
- MDW
1 stop5h 55m
Southwest
Wed 9/96:00 pm
MDW
- EUG
1 stop6h 30m
Southwest
Deal found 6/11![Southwest logo]()
$278
Best flights from Oregon to IllinoisDiscover carefully curated flight deals from Oregon to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated June 15, 2026.
Discover carefully curated flight deals from Oregon to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated June 15, 2026.
This Southwest deal was found by Cheapflights users on 6/11. 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.
Tue 12/810:15 am
PDX
- STL
2 stops9h 45m
Southwest
Tue 12/156:00 am
STL
- PDX
1 stop6h 55m
Southwest
Deal found 6/11![Southwest logo]()
$252
This Delta deal was found by Cheapflights users on 6/10. 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.
Tue 9/296:10 am
EUG
- ORD
1 stop9h 03m
Delta
Fri 10/27:40 pm
ORD
- EUG
1 stop6h 17m
Delta
Deal found 6/10![Delta logo]()
$297
This United Airlines deal was found by Cheapflights users on 6/14. Clicking the “Pick Dates” 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 10/79:00 am
PDX
- STL
1 stop7h 43m
United Airlines
Wed 10/141:36 pm
STL
- PDX
1 stop6h 10m
United Airlines
Deal found 6/14![United Airlines logo]()
$319
This Alaska Airlines deal was found by Cheapflights users on 6/12. 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.
Wed 8/510:59 pm
PDX
- ORD
Nonstop4h 01m
Alaska Airlines
Tue 8/188:20 pm
ORD
- PDX
1 stop13h 51m
Alaska Airlines
Deal found 6/12![Alaska Airlines logo]()
$325
This Southwest deal was found by Cheapflights users on 6/11. 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.
Mon 8/3112:20 pm
EUG
- MDW
1 stop5h 55m
Southwest
Wed 9/96:00 pm
MDW
- EUG
1 stop6h 30m
Southwest
Deal found 6/11![Southwest logo]()
$278
This Delta deal was found by Cheapflights users on 6/12. 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.
Mon 8/315:20 am
EUG
- MDW
2 stops10h 41m
Delta
Wed 9/92:00 pm
MDW
- EUG
2 stops10h 51m
Delta
Deal found 6/12![Delta logo]()
$307
This Southwest deal was found by Cheapflights users on 6/11. 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.
Wed 9/211:30 pm
PDX
- STL
1 stop9h 00m
Southwest
Sat 9/52:25 pm
STL
- PDX
2 stops8h 40m
Southwest
Deal found 6/11![Southwest logo]()
$290
This United Airlines deal was found by Cheapflights users on 6/13. Clicking the “Pick Dates” 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 7/2811:40 pm
PDX
- STL
1 stop7h 09m
United Airlines
Sat 8/17:23 pm
STL
- PDX
1 stop7h 27m
United Airlines
Deal found 6/13![United Airlines logo]()
$319
This Alaska Airlines deal was found by Cheapflights users on 6/10. 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 10/147:00 am
PDX
- ORD
Nonstop4h 21m
Alaska Airlines
Sat 10/172:17 pm
ORD
- PDX
Nonstop4h 37m
Alaska Airlines
Deal found 6/10![Alaska Airlines logo]()
$333
This Delta deal was found by Cheapflights users on 6/10. 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.
Tue 7/216:15 am
PDX
- STL
1 stop6h 58m
Delta
Thu 7/237:55 pm
STL
- PDX
1 stop5h 49m
Delta
Deal found 6/10![Delta logo]()
$319
This United Airlines deal was found by Cheapflights users on 6/12. 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.
Thu 10/82:15 pm
EUG
- ORD
Nonstop4h 11m
United Airlines
Mon 10/129:05 am
ORD
- EUG
Nonstop4h 45m
United Airlines
Deal found 6/12![United Airlines logo]()
$329
This Alaska Airlines deal was found by Cheapflights users on 6/14. Clicking the “Pick Dates” 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 8/310:59 pm
PDX
- ORD
Nonstop4h 01m
Alaska Airlines
Mon 8/177:20 am
ORD
- PDX
Nonstop4h 25m
Alaska Airlines
Deal found 6/14![Alaska Airlines logo]()
$337
This Southwest deal was found by Cheapflights users on 6/13. Clicking the “Pick Dates” 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 8/276:05 am
PDX
- STL
1 stop8h 15m
Southwest
Sun 8/306:00 am
STL
- PDX
1 stop8h 45m
Southwest
Deal found 6/13![Southwest logo]()
$319
This Delta deal was found by Cheapflights users on 6/14. Clicking the “Pick Dates” 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 7/143:00 pm
PDX
- STL
1 stop6h 22m
Delta
Wed 7/297:55 pm
STL
- PDX
1 stop5h 49m
Delta
Deal found 6/14![Delta logo]()
$319
This United Airlines deal was found by Cheapflights users on 6/10. 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.
Wed 9/164:07 pm
PDX
- ORD
1 stop5h 52m
United Airlines
Mon 9/218:12 pm
ORD
- PDX
Nonstop4h 40m
United Airlines
Deal found 6/10![United Airlines logo]()
$332
This Alaska Airlines deal was found by Cheapflights users on 6/13. Clicking the “Pick Dates” 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 8/610:59 pm
PDX
- ORD
Nonstop4h 01m
Alaska Airlines
Mon 8/108:20 pm
ORD
- PDX
1 stop13h 17m
Alaska Airlines
Deal found 6/13![Alaska Airlines logo]()
$347
This Southwest deal was found by Cheapflights users on 6/13. Clicking the “Pick Dates” 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 8/1311:30 pm
PDX
- STL
1 stop7h 45m
Southwest
Sun 8/166:10 am
STL
- PDX
1 stop6h 25m
Southwest
Deal found 6/13![Southwest logo]()
$319
This Delta deal was found by Cheapflights users on 6/10. 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 8/2710:55 pm
PDX
- MDW
1 stop9h 04m
Delta
Mon 8/316:05 am
MDW
- PDX
1 stop8h 53m
Delta
Deal found 6/10![Delta logo]()
$321
This United Airlines deal was found by Cheapflights users on 6/14. Clicking the “Pick Dates” 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 7/155:46 pm
BOI
- ORD
1 stop5h 58m
United Airlines
Tue 7/218:40 am
ORD
- BOI
Nonstop3h 52m
United Airlines
Deal found 6/14![United Airlines logo]()
$335
This Alaska Airlines deal was found by Cheapflights users on 6/13. Clicking the “Pick Dates” 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 8/134:00 pm
EUG
- ORD
1 stop11h 00m
Alaska Airlines
Mon 8/175:42 pm
ORD
- EUG
1 stop8h 17m
Alaska Airlines
Deal found 6/13![Alaska Airlines logo]()
$349
This Southwest deal was found by Cheapflights users on 6/11. 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.
Wed 7/85:15 am
PDX
- STL
1 stop9h 05m
Southwest
Wed 7/155:55 pm
STL
- PDX
1 stop7h 40m
Southwest
Deal found 6/11![Southwest logo]()
$319
This Delta deal was found by Cheapflights users on 6/14. Clicking the “Pick Dates” 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 8/123:25 pm
PDX
- ORD
1 stop6h 04m
Delta
Wed 8/197:44 pm
ORD
- PDX
1 stop5h 55m
Delta
Deal found 6/14![Delta logo]()
$335
This United Airlines deal was found by Cheapflights users on 6/14. Clicking the “Pick Dates” 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 9/252:27 pm
PDX
- ORD
Nonstop4h 13m
United Airlines
Sat 10/38:40 am
ORD
- PDX
1 stop7h 46m
United Airlines
Deal found 6/14![United Airlines logo]()
$336
This Alaska Airlines deal was found by Cheapflights users on 6/11. 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.
Wed 7/2912:34 pm
EUG
- ORD
1 stop14h 26m
Alaska Airlines
Tue 8/46:00 am
ORD
- EUG
1 stop9h 01m
Alaska Airlines
Deal found 6/11![Alaska Airlines logo]()
$349
This Southwest deal was found by Cheapflights users on 6/12. 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 7/295:15 am
PDX
- STL
1 stop9h 05m
Southwest
Wed 7/295:55 pm
STL
- PDX
1 stop7h 40m
Southwest
Deal found 6/12![Southwest logo]()
$319
This United Airlines deal was found by Cheapflights users on 6/14. Clicking the “Pick Dates” 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 8/2011:02 pm
PDX
- ORD
Nonstop4h 01m
United Airlines
Sun 8/238:50 am
ORD
- PDX
Nonstop4h 38m
United Airlines
Deal found 6/14![United Airlines logo]()
$337
This Delta deal was found by Cheapflights users on 6/13. Clicking the “Pick Dates” 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 9/231:25 pm
PDX
- ORD
1 stop7h 56m
Delta
Sun 9/276:15 am
ORD
- PDX
1 stop8h 32m
Delta
Deal found 6/13![Delta logo]()
$346
This Alaska Airlines deal was found by Cheapflights users on 6/15. Clicking the “Pick Dates” 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 7/287:50 am
EUG
- ORD
1 stop9h 07m
Alaska Airlines
Tue 8/46:00 am
ORD
- EUG
1 stop9h 01m
Alaska Airlines
Deal found 6/15![Alaska Airlines logo]()
$349
This Southwest deal was found by Cheapflights users on 6/11. 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 9/176:20 am
PDX
- MDW
2 stops8h 40m
Southwest
Mon 9/215:00 pm
MDW
- PDX
2 stops7h 45m
Southwest
Deal found 6/11![Southwest logo]()
$321
This Delta deal was found by Cheapflights users on 6/13. Clicking the “Pick Dates” 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 8/271:15 pm
PDX
- ORD
1 stop6h 15m
Delta
Tue 9/16:00 am
ORD
- PDX
1 stop6h 41m
Delta
Deal found 6/13![Delta logo]()
$346
Last-minute flights from Oregon to IllinoisDiscover last-minute flight deals from Oregon to Illinois. Data last updated June 15, 2026 and is based on user searches.
Discover last-minute flight deals from Oregon to Illinois. Data last updated June 15, 2026 and is based on user searches.
This United Airlines deal was found by Cheapflights users on 6/11. 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.
Thu 7/212:50 pm
EUG
- ORD
Nonstop4h 10m
United Airlines
Sun 7/58:53 am
ORD
- EUG
Nonstop4h 44m
United Airlines
Deal found 6/11![United Airlines logo]()
$309
This United Airlines deal was found by Cheapflights users on 6/14. Clicking the “Pick Dates” 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 7/612:50 pm
EUG
- ORD
Nonstop4h 10m
United Airlines
Sat 7/119:00 am
ORD
- EUG
Nonstop4h 44m
United Airlines
Deal found 6/14![United Airlines logo]()
$319
This United Airlines deal was found by Cheapflights users on 6/10. 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.
Wed 7/811:40 pm
PDX
- STL
1 stop6h 59m
United Airlines
Fri 8/144:40 pm
STL
- PDX
1 stop6h 25m
United Airlines
Deal found 6/10![United Airlines logo]()
$305
This CheapOair deal was found by Cheapflights users on 6/12. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/85:21 pm
PDX
- STL
1 stop24h 02m
Frontier
Wed 7/157:03 pm
STL
- PDX
1 stop25h 01m
Frontier
Deal found 6/12![Frontier logo]()
$315
This Alaska Airlines deal was found by Cheapflights users on 6/11. 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.
Sat 7/1110:59 pm
PDX
- ORD
Nonstop4h 01m
Alaska Airlines
Sun 7/127:20 am
ORD
- PDX
Nonstop4h 25m
Alaska Airlines
Deal found 6/11![Alaska Airlines logo]()
$321
This Delta deal was found by Cheapflights users on 6/14. Clicking the “Pick Dates” 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 7/1312:33 am
PDX
- STL
1 stop6h 13m
Delta
Mon 7/207:55 pm
STL
- PDX
1 stop5h 49m
Delta
Deal found 6/14![Delta logo]()
$319
This Delta deal was found by Cheapflights users on 6/11. 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 7/1412:32 pm
EUG
- ORD
1 stop9h 06m
Delta
Wed 7/226:55 am
ORD
- EUG
1 stop8h 03m
Delta
Deal found 6/11![Delta logo]()
$297
This United Airlines deal was found by Cheapflights users on 6/11. 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.
Tue 7/1411:40 pm
PDX
- STL
1 stop7h 09m
United Airlines
Wed 7/157:23 pm
STL
- PDX
1 stop7h 27m
United Airlines
Deal found 6/11![United Airlines logo]()
$314
This Alaska Airlines deal was found by Cheapflights users on 6/10. 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.
Tue 7/1410:59 pm
PDX
- ORD
Nonstop4h 01m
Alaska Airlines
Sat 7/187:20 am
ORD
- PDX
Nonstop4h 25m
Alaska Airlines
Deal found 6/10![Alaska Airlines logo]()
$320
This Travelocity deal was found by Cheapflights users on 6/10. 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 Travelocity is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/1710:59 pm
PDX
- ORD
Nonstop4h 01m
Alaska Airlines
Fri 8/78:20 pm
ORD
- PDX
1 stop13h 17m
Alaska Airlines
Deal found 6/10![Alaska Airlines logo]()
$322
This Southwest deal was found by Cheapflights users on 6/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/1811:30 pm
PDX
- MDW
Nonstop3h 50m
Southwest
Sat 7/258:25 pm
MDW
- PDX
Nonstop4h 25m
Southwest
Deal found 6/14![Southwest logo]()
$320
This CheapOair deal was found by Cheapflights users on 6/12. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/295:21 pm
PDX
- STL
1 stop24h 02m
Frontier
Tue 8/48:08 pm
STL
- PDX
1 stop22h 28m
Frontier
Deal found 6/12![Frontier logo]()
$275
One-way flights from Oregon to IllinoisSearch for one-way flight options from Oregon to Illinois. Find affordable one-way fares based on user searches. Data last updated June 15, 2026.
Search for one-way flight options from Oregon to Illinois. Find affordable one-way fares based on user searches. Data last updated June 15, 2026.
This American Airlines deal was found by Cheapflights users on 6/11. 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.
Tue 12/81:36 pm
BOI
- ORD
Nonstop3h 43m
American Airlines
Deal found 6/11![American Airlines logo]()
$104
This Delta deal was found by Cheapflights users on 6/10. 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 8/55:08 pm
PDX
- STL
1 stop5h 33m
Delta
Deal found 6/10![Delta logo]()
$106
This Delta deal was found by Cheapflights users on 6/11. 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.
Wed 9/95:40 am
BOI
- MDW
1 stop6h 31m
Delta
Deal found 6/11![Delta logo]()
$114
This Delta deal was found by Cheapflights users on 6/10. 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.
Tue 9/81:15 pm
BOI
- ORD
1 stop7h 43m
Delta
Deal found 6/10![Delta logo]()
$114
This Delta deal was found by Cheapflights users on 6/10. 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 9/98:40 am
BOI
- ORD
2 stops12h 18m
Delta
Deal found 6/10![Delta logo]()
$119
This Southwest deal was found by Cheapflights users on 6/11. 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.
Tue 9/83:40 pm
BOI
- MDW
1 stop13h 10m
Southwest
Deal found 6/11![Southwest logo]()
$122
This Frontier deal was found by Cheapflights users on 6/12. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/81:04 pm
BOI
- ORD
1 stop6h 49m
Frontier
Deal found 6/12![Frontier logo]()
$125
This American Airlines deal was found by Cheapflights users on 6/11. 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.
Sat 8/82:58 pm
BOI
- ORD
Nonstop3h 51m
American Airlines
Deal found 6/11![American Airlines logo]()
$126
This Delta deal was found by Cheapflights users on 6/10. 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 8/65:08 pm
PDX
- STL
1 stop5h 33m
Delta
Deal found 6/10![Delta logo]()
$126
This Kiwi.com deal was found by Cheapflights users on 6/12. 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.
Tue 8/115:16 pm
PDX
- STL
1 stop24h 07m
Frontier
Deal found 6/12![Frontier logo]()
$128
This Southwest deal was found by Cheapflights users on 6/11. 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.
Tue 12/86:55 am
PDX
- STL
2 stops8h 25m
Southwest
Deal found 6/11![Southwest logo]()
$129
This CheapOair deal was found by Cheapflights users on 6/12. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/36:19 pm
PDX
- STL
1 stop17h 47m
Frontier
Deal found 6/12![Frontier logo]()
$131
Find flight deals from Oregon to Illinois
Keep the following information in mind while searching for Oregon to Illinois flight deals. Data was last updated June 15, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $211 (Delta) |
One-way from | $104 (American Airlines) |
Popular in | November |
Cheapest in | January |
Average price | $384 |
Good round-trip deal | $390 or less |
Good one-way deal | $216 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Oregon 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 June 15, 2026.
Use the filters below to find and compare flights from Oregon to Illinois that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
PortlandSt. Louis
PDX - STL
PDXSTL
Portland
Tue 12/8
10:15 am-10:00 pm
2 stops9h 45m
Lambert-St Louis
Tue 12/15
6:00 am-10:55 am
1 stop6h 55m
$252
EugeneChicago
EUG - MDW
EUGMDW
Eugene
Mon 8/31
12:20 pm-8:15 pm
1 stop5h 55m
Chicago Midway
Wed 9/9
6:00 pm-10:30 pm
1 stop6h 30m
$278
PortlandSt. Louis
PDX - STL
PDXSTL
Portland
Wed 9/2
11:30 pm-10:30 am
1 stop9h 00m
Lambert-St Louis
Sat 9/5
2:25 pm-9:05 pm
2 stops8h 40m
$290
EugeneChicago
EUG - ORD
EUGORD
Eugene
Tue 9/29
6:10 am-5:13 pm
1 stop9h 03m
Chicago O'Hare Intl
Fri 10/2
7:40 pm-11:57 pm
1 stop6h 17m
$297
EugeneChicago
EUG - MDW
EUGMDW
Eugene
Mon 8/31
5:20 am-6:01 pm
2 stops10h 41m
Chicago Midway
Wed 9/9
2:00 pm-10:51 pm
2 stops10h 51m
$307
PortlandSt. Louis
PDX - STL
PDXSTL
Portland
Wed 10/7
9:00 am-6:43 pm
1 stop7h 43m
Lambert-St Louis
Wed 10/14
1:36 pm-5:46 pm
1 stop6h 10m
$319
PortlandSt. Louis
PDX - STL
PDXSTL
Portland
Tue 7/28
11:40 pm-8:49 am
1 stop7h 09m
Lambert-St Louis
Sat 8/1
7:23 pm-12:50 am
1 stop7h 27m
$319
PortlandSt. Louis
PDX - STL
PDXSTL
Portland
Tue 7/21
6:15 am-3:13 pm
1 stop6h 58m
Lambert-St Louis
Thu 7/23
7:55 pm-11:44 pm
1 stop5h 49m
$319
PortlandSt. Louis
PDX - STL
PDXSTL
Portland
Thu 8/27
6:05 am-4:20 pm
1 stop8h 15m
Lambert-St Louis
Sun 8/30
6:00 am-12:45 pm
1 stop8h 45m
$319
PortlandSt. Louis
PDX - STL
PDXSTL
Portland
Tue 7/14
3:00 pm-11:22 pm
1 stop6h 22m
Lambert-St Louis
Wed 7/29
7:55 pm-11:44 pm
1 stop5h 49m
$319
Showing 1-10 of 60 resultsSorted by cheapest first
Best time to book a flight from Oregon to Illinois
Have a flexible travel schedule? Discover the best time to fly to Illinois from Oregon with our price prediction graph.
PDX-STL
EUG-ORD
PDX-ORD
PDX-MDW
EUG-MDW
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 Oregon to Illinois
USOR-USIL
PDX-STL
EUG-ORD
PDX-ORD
PDX-MDW
What is the cheapest month to book a flight from Oregon to Illinois?
Currently, April is the cheapest month in which you can book a flight from Oregon to Illinois (average of $108). Flying from Oregon to Illinois in November is currently the most expensive (average of $797). 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 OR to IL?
Find hourly flight availability from Oregon 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 June 15, 2026.
It’s optimal to fly from Oregon to Illinois in the afternoon. By choosing this option you can save up to 35% on the cost of your flight, compared to a flight at noon.
Weekly flight availability from Oregon to Illinois
Explore weekly flight availability from Oregon 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 June 15, 2026.
The most flights from USOR to USIL are scheduled on a Friday (35 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (25 on average).
How much does it cost to fly round-trip from Oregon to Illinois?
How far ahead should I book a flight from Oregon to Illinois?
The best time to book flights from Oregon to Illinois is 42 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.
What is the cheapest day to fly from Oregon to Illinois?
Use this chart to determine the cheapest time to fly round-trip from Oregon to Illinois. Price data was last updated on June 13, 2026.
Travelers seeking maximum savings on their Oregon to Illinois flight should consider departing on Saturday at noon 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 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 June 15, 2026.
Peruse reviews from past customers who have flown with Alaska Airlines,Southwest, andDelta from Oregon to Illinois to help guide your decision. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Boarding
8.1
Crew
8.5
Overall
7.9
Entertainment
7.0
Comfort
7.8
Food
7.0
Reviews
1 / 20
4.0
OkayAnonymous,Jun 2026
SEA - RNO
Boarding
8.1
Crew
8.5
Overall
7.9
Entertainment
7.0
Comfort
7.8
Food
7.0
Reviews
1 / 20
4.0
OkayAnonymous,Jun 2026
SEA - RNO
Boarding
8.1
Crew
8.5
Overall
7.9
Entertainment
7.0
Comfort
7.8
Food
7.0
Reviews
1 / 20
4.0
OkayAnonymous,Jun 2026
SEA - RNO
Boarding
8.1
Crew
8.5
Overall
7.9
Entertainment
7.0
Comfort
7.8
Food
7.0
Reviews
1 / 20
4.0
OkayAnonymous,Jun 2026
SEA - RNO
Boarding
8.1
Crew
8.5
Overall
7.9
Entertainment
7.0
Comfort
7.8
Food
7.0
Reviews
1 / 20
4.0
OkayAnonymous,Jun 2026
SEA - RNO
Boarding
8.1
Crew
8.5
Overall
7.9
Entertainment
7.0
Comfort
7.8
Food
7.0
Reviews
1 / 20
4.0
OkayAnonymous,Jun 2026
SEA - RNO
Related info for your journey
Find useful and relevant information for your journey from Oregon to Illinois. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
Browse thousands of different options on Cheapflights for your next trip
Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.
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Alternative routes for Oregon 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 Oregon to Illinois by cabin class
Find flights from Oregon to Illinois, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Oregon and Illinois flights
Browse other Oregon and Illinois flight options. Last updated on June 15, 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 Oregon after your stay in Illinois
Oregon to Illinois flights
Consider these flights traveling from Oregon to Illinois.
Top 7 airlines flying from Oregon to Illinois
Discover the top 7 airlines that operate flights from Oregon 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 June 15, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$93 | Average$249 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$96 | Average$238 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$108 | Average$352 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$171 | Average$441 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$179 | Average$386 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$198 | Average$402 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$216 | Average$456 | FlexibilityNo cancel fee | On-time69% |