$94+ 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 4/2. Fares are subject to change and may not be available on all flights or dates of travel.
PDX — ORD
Apr 17 — Apr 241
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
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
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Cheapest flights from 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 March 18, 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 March 18, 2026.
This American Airlines deal was found by Cheapflights users on 3/15. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/2211:47 pm
PDX
- STL
1 stop6h 37m
American Airlines
Wed 4/295:20 am
STL
- PDX
1 stop7h 41m
American Airlines
Deal found 3/15![American Airlines logo]()
$217
This Kiwi.com deal was found by Cheapflights users on 3/14. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/1512:28 pm
PDX
- ORD
2 stops19h 55m
Multiple Airlines
Wed 5/69:42 pm
ORD
- PDX
1 stop21h 04m
Multiple Airlines
Deal found 3/14![Multiple Airlines logo]()
$219
This CheapOair deal was found by Cheapflights users on 3/13. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/303:05 pm
PDX
- ORD
1 stop13h 15m
Frontier
Sat 5/27:21 pm
ORD
- PDX
1 stop18h 29m
Frontier
Deal found 3/13![Frontier logo]()
$221
This CheapOair deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” 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 5/118:46 pm
PDX
- STL
1 stop19h 20m
Frontier
Sat 5/169:18 pm
STL
- PDX
1 stop25h 33m
Frontier
Deal found 3/16![Frontier logo]()
$221
This Kiwi.com deal was found by Cheapflights users on 3/14. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/1512:28 pm
PDX
- ORD
1 stop19h 22m
Frontier
Sat 5/27:21 pm
ORD
- PDX
1 stop18h 29m
Frontier
Deal found 3/14![Frontier logo]()
$222
This Booking.com deal was found by Cheapflights users on 3/14. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/169:54 am
PDX
- ORD
1 stop17h 56m
Frontier
Fri 4/1710:55 am
ORD
- PDX
1 stop26h 47m
Frontier
Deal found 3/14![Frontier logo]()
$223
This Kiwi.com deal was found by Cheapflights users on 3/13. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/1011:58 am
PDX
- STL
1 stop19h 50m
Frontier
Fri 4/178:06 pm
STL
- PDX
1 stop17h 36m
Frontier
Deal found 3/13![Frontier logo]()
$223
This Kiwi.com deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” 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 5/212:27 pm
PDX
- ORD
2 stops15h 41m
Frontier
Wed 5/69:42 pm
ORD
- PDX
1 stop21h 04m
Frontier
Deal found 3/16![Frontier logo]()
$224
This Mytrip deal was found by Cheapflights users on 3/15. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/1812:27 pm
PDX
- ORD
1 stop19h 18m
Frontier
Sat 4/257:21 pm
ORD
- PDX
1 stop18h 29m
Frontier
Deal found 3/15![Frontier logo]()
$225
This Kiwi.com deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” 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 4/2912:38 pm
PDX
- ORD
2 stops21h 35m
Frontier
Wed 5/69:42 pm
ORD
- PDX
1 stop21h 04m
Frontier
Deal found 3/16![Frontier logo]()
$230
This Kiwi.com deal was found by Cheapflights users on 3/14. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/1512:28 pm
PDX
- ORD
1 stop19h 22m
Frontier
Sat 4/187:21 pm
ORD
- PDX
1 stop18h 29m
Frontier
Deal found 3/14![Frontier logo]()
$233
This Kiwi.com deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” 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 4/2512:27 pm
PDX
- ORD
2 stops15h 53m
Frontier
Wed 5/69:42 pm
ORD
- PDX
1 stop21h 04m
Frontier
Deal found 3/17![Frontier logo]()
$237
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 March 18, 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 March 18, 2026.
This American Airlines deal was found by Cheapflights users on 3/13. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/163:16 pm
PDX
- STL
1 stop6h 30m
American Airlines
Sat 4/185:21 pm
STL
- PDX
1 stop8h 36m
American Airlines
Deal found 3/13![American Airlines logo]()
$237
This Alaska Airlines deal was found by Cheapflights users on 3/13. 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.
Fri 5/18:38 pm
EUG
- ORD
1 stop8h 02m
Alaska Airlines
Fri 5/88:48 pm
ORD
- EUG
1 stop17h 58m
Alaska Airlines
Deal found 3/13![Alaska Airlines logo]()
$257
This Southwest deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” 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 5/2711:20 am
EUG
- ORD
1 stop9h 35m
Southwest
Mon 6/16:15 pm
ORD
- EUG
1 stop6h 30m
Southwest
Deal found 3/17![Southwest logo]()
$257
This Delta deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” 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 4/146:30 am
EUG
- ORD
2 stops12h 48m
Delta
Tue 4/216:00 pm
ORD
- EUG
1 stop7h 58m
Delta
Deal found 3/16![Delta logo]()
$262
This United Airlines deal was found by Cheapflights users on 3/14. 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.
Sat 4/1811:59 pm
PDX
- ORD
Nonstop4h 04m
United Airlines
Sat 4/256:20 pm
ORD
- PDX
1 stop8h 24m
United Airlines
Deal found 3/14![United Airlines logo]()
$281
This Southwest deal was found by Cheapflights users on 3/13. 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.
Tue 4/285:20 pm
EUG
- MDW
1 stop9h 40m
Southwest
Tue 5/56:30 am
MDW
- EUG
1 stop6h 15m
Southwest
Deal found 3/13![Southwest logo]()
$257
This Delta deal was found by Cheapflights users on 3/13. 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.
Tue 4/286:30 am
EUG
- ORD
2 stops9h 34m
Delta
Tue 5/57:10 pm
ORD
- EUG
1 stop6h 37m
Delta
Deal found 3/13![Delta logo]()
$262
This Alaska Airlines deal was found by Cheapflights users on 3/13. 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.
Tue 4/142:22 pm
BOI
- STL
1 stop8h 37m
Alaska Airlines
Wed 4/157:00 am
STL
- BOI
1 stop9h 29m
Alaska Airlines
Deal found 3/13![Alaska Airlines logo]()
$277
This United Airlines deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” 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 5/164:15 pm
PDX
- ORD
1 stop6h 43m
United Airlines
Wed 5/277:05 am
ORD
- PDX
Nonstop4h 34m
United Airlines
Deal found 3/17![United Airlines logo]()
$288
This Southwest deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” 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 5/2711:20 am
EUG
- MDW
2 stops10h 00m
Southwest
Mon 6/15:15 pm
MDW
- EUG
1 stop7h 30m
Southwest
Deal found 3/17![Southwest logo]()
$262
This Alaska Airlines deal was found by Cheapflights users on 3/13. 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.
Sat 4/257:35 am
MFR
- ORD
1 stop9h 28m
Alaska Airlines
Tue 5/58:48 pm
ORD
- MFR
1 stop18h 04m
Alaska Airlines
Deal found 3/13![Alaska Airlines logo]()
$277
This Delta deal was found by Cheapflights users on 3/13. 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.
Mon 4/2711:15 pm
PDX
- STL
1 stop8h 27m
Delta
Mon 5/46:45 pm
STL
- PDX
1 stop7h 08m
Delta
Deal found 3/13![Delta logo]()
$277
This United Airlines deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” 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 5/611:59 pm
PDX
- STL
1 stop7h 31m
United Airlines
Fri 5/85:59 pm
STL
- PDX
1 stop6h 55m
United Airlines
Deal found 3/17![United Airlines logo]()
$288
This Southwest deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” 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 4/1811:55 pm
PDX
- MDW
Nonstop3h 55m
Southwest
Sat 4/256:05 pm
MDW
- PDX
Nonstop4h 20m
Southwest
Deal found 3/17![Southwest logo]()
$271
This Delta deal was found by Cheapflights users on 3/18. Clicking the “Pick Dates” 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 4/286:30 am
EUG
- ORD
2 stops12h 48m
Delta
Thu 4/306:00 pm
ORD
- EUG
1 stop7h 58m
Delta
Deal found 3/18![Delta logo]()
$293
This United Airlines deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” 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 4/188:40 am
PDX
- STL
2 stops10h 33m
United Airlines
Thu 4/236:05 pm
STL
- PDX
1 stop6h 49m
United Airlines
Deal found 3/17![United Airlines logo]()
$298
This Alaska Airlines deal was found by Cheapflights users on 3/14. 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.
Tue 4/141:35 pm
PDX
- STL
1 stop8h 24m
Alaska Airlines
Wed 4/157:00 am
STL
- PDX
1 stop7h 35m
Alaska Airlines
Deal found 3/14![Alaska Airlines logo]()
$312
This Southwest deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” 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 4/181:35 pm
PDX
- ORD
1 stop6h 45m
Southwest
Sat 4/257:00 am
ORD
- PDX
2 stops13h 45m
Southwest
Deal found 3/16![Southwest logo]()
$296
This Delta deal was found by Cheapflights users on 3/14. 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 4/216:16 pm
BOI
- STL
1 stop5h 09m
Delta
Tue 4/286:45 pm
STL
- BOI
1 stop6h 12m
Delta
Deal found 3/14![Delta logo]()
$297
This United Airlines deal was found by Cheapflights users on 3/13. 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.
Mon 5/1110:55 pm
PDX
- ORD
Nonstop4h 07m
United Airlines
Wed 5/138:00 pm
ORD
- PDX
Nonstop4h 35m
United Airlines
Deal found 3/13![United Airlines logo]()
$299
This Alaska Airlines deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” 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 4/181:22 pm
MFR
- ORD
1 stop8h 37m
Alaska Airlines
Tue 4/216:00 am
ORD
- MFR
1 stop8h 45m
Alaska Airlines
Deal found 3/16![Alaska Airlines logo]()
$317
This Southwest deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” 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 6/102:40 pm
EUG
- MDW
1 stop5h 45m
Southwest
Tue 6/167:00 am
MDW
- EUG
2 stops8h 00m
Southwest
Deal found 3/16![Southwest logo]()
$298
This Delta deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” 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 4/156:05 am
RDM
- ORD
2 stops9h 59m
Delta
Wed 4/227:35 am
ORD
- RDM
2 stops11h 26m
Delta
Deal found 3/16![Delta logo]()
$307
This United Airlines deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” 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 4/174:15 pm
PDX
- ORD
1 stop6h 15m
United Airlines
Wed 4/229:10 am
ORD
- PDX
Nonstop4h 36m
United Airlines
Deal found 3/17![United Airlines logo]()
$309
This Southwest deal was found by Cheapflights users on 3/13. 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.
Sat 5/97:10 am
PDX
- ORD
2 stops13h 10m
Southwest
Sat 5/164:15 pm
ORD
- PDX
1 stop7h 30m
Southwest
Deal found 3/13![Southwest logo]()
$306
This United Airlines deal was found by Cheapflights users on 3/13. 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.
Mon 5/2511:40 pm
PDX
- ORD
Nonstop4h 05m
United Airlines
Wed 5/271:29 pm
ORD
- PDX
Nonstop4h 27m
United Airlines
Deal found 3/13![United Airlines logo]()
$316
This Delta deal was found by Cheapflights users on 3/13. 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.
Tue 4/711:15 pm
PDX
- STL
1 stop8h 31m
Delta
Wed 4/157:00 am
STL
- PDX
2 stops12h 10m
Delta
Deal found 3/13![Delta logo]()
$316
This Alaska Airlines deal was found by Cheapflights users on 3/15. 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.
Fri 4/245:56 pm
BOI
- ORD
1 stop18h 17m
Alaska Airlines
Sun 4/266:00 am
ORD
- BOI
1 stop7h 35m
Alaska Airlines
Deal found 3/15![Alaska Airlines logo]()
$356
This Southwest deal was found by Cheapflights users on 3/13. 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.
Mon 5/255:10 am
PDX
- MDW
Nonstop3h 55m
Southwest
Wed 5/278:50 pm
MDW
- PDX
Nonstop4h 20m
Southwest
Deal found 3/13![Southwest logo]()
$316
This United Airlines deal was found by Cheapflights users on 3/15. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/711:55 pm
PDX
- ORD
Nonstop4h 05m
United Airlines
Sun 5/109:20 pm
ORD
- PDX
Nonstop4h 35m
United Airlines
Deal found 3/15![United Airlines logo]()
$327
Last-minute flights from Oregon to IllinoisDiscover last-minute flight deals from Oregon to Illinois. Data last updated March 18, 2026 and is based on user searches.
Discover last-minute flight deals from Oregon to Illinois. Data last updated March 18, 2026 and is based on user searches.
This Kiwi.com deal was found by Cheapflights users on 3/13. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/1011:58 am
PDX
- STL
1 stop19h 50m
Frontier
Fri 4/178:06 pm
STL
- PDX
1 stop17h 36m
Frontier
Deal found 3/13![Frontier logo]()
$223
This Kiwi.com deal was found by Cheapflights users on 3/14. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/141:48 pm
PDX
- ORD
2 stops25h 12m
Frontier
Mon 4/2010:55 am
ORD
- PDX
1 stop26h 57m
Frontier
Deal found 3/14![Frontier logo]()
$238
This Kiwi.com deal was found by Cheapflights users on 3/14. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/1512:28 pm
PDX
- ORD
2 stops19h 55m
Multiple Airlines
Wed 5/69:42 pm
ORD
- PDX
1 stop21h 04m
Multiple Airlines
Deal found 3/14![Multiple Airlines logo]()
$219
This Kiwi.com deal was found by Cheapflights users on 3/14. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/1512:28 pm
PDX
- ORD
1 stop19h 22m
Frontier
Mon 4/208:58 pm
ORD
- PDX
2 stops16h 54m
Frontier
Deal found 3/14![Frontier logo]()
$222
This Kiwi.com deal was found by Cheapflights users on 3/14. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/1512:28 pm
PDX
- ORD
1 stop19h 22m
Frontier
Sat 4/187:21 pm
ORD
- PDX
1 stop18h 29m
Frontier
Deal found 3/14![Frontier logo]()
$233
This Booking.com deal was found by Cheapflights users on 3/14. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/169:54 am
PDX
- ORD
1 stop17h 56m
Frontier
Fri 4/1710:55 am
ORD
- PDX
1 stop26h 47m
Frontier
Deal found 3/14![Frontier logo]()
$223
This Delta deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” 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 4/169:55 am
PDX
- STL
1 stop5h 31m
Delta
Sat 4/186:19 am
STL
- PDX
1 stop8h 30m
Delta
Deal found 3/17![Delta logo]()
$237
This Mytrip deal was found by Cheapflights users on 3/15. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/1812:27 pm
PDX
- ORD
1 stop19h 18m
Frontier
Sat 4/257:21 pm
ORD
- PDX
1 stop18h 29m
Frontier
Deal found 3/15![Frontier logo]()
$224
This American Airlines deal was found by Cheapflights users on 3/15. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/2211:47 pm
PDX
- STL
1 stop6h 37m
American Airlines
Wed 4/295:20 am
STL
- PDX
1 stop7h 41m
American Airlines
Deal found 3/15![American Airlines logo]()
$217
This Kiwi.com deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” 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 4/2512:27 pm
PDX
- ORD
2 stops15h 53m
Frontier
Wed 5/69:42 pm
ORD
- PDX
1 stop21h 04m
Frontier
Deal found 3/17![Frontier logo]()
$237
This Kiwi.com deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” 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 4/2912:38 pm
PDX
- ORD
2 stops21h 35m
Frontier
Wed 5/69:42 pm
ORD
- PDX
1 stop21h 04m
Frontier
Deal found 3/16![Frontier logo]()
$230
This CheapOair deal was found by Cheapflights users on 3/13. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/303:05 pm
PDX
- ORD
1 stop13h 15m
Frontier
Sat 5/27:21 pm
ORD
- PDX
1 stop18h 29m
Frontier
Deal found 3/13![Frontier logo]()
$221
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 March 18, 2026.
Search for one-way flight options from Oregon to Illinois. Find affordable one-way fares based on user searches. Data last updated March 18, 2026.
This Kiwi.com deal was found by Cheapflights users on 3/18. Clicking the “Pick Dates” 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 4/212:03 pm
BOI
- STL
1 stop20h 45m
Frontier
Deal found 3/18![Frontier logo]()
$94
This Kiwi.com deal was found by Cheapflights users on 3/13. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/1011:58 am
PDX
- STL
1 stop19h 50m
Frontier
Deal found 3/13![Frontier logo]()
$94
This Kiwi.com deal was found by Cheapflights users on 3/13. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/1512:28 pm
PDX
- STL
1 stop28h 53m
Frontier
Deal found 3/13![Frontier logo]()
$104
This Frontier deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” 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 5/121:22 pm
BOI
- ORD
1 stop6h 15m
Frontier
Deal found 3/16![Frontier logo]()
$105
This Super.com deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/75:31 pm
PDX
- ORD
1 stop11h 08m
Frontier
Deal found 3/17![Frontier logo]()
$109
This American Airlines deal was found by Cheapflights users on 3/15. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/286:00 am
PDX
- STL
1 stop9h 21m
American Airlines
Deal found 3/15![American Airlines logo]()
$109
This Frontier deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” 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 5/145:31 pm
PDX
- ORD
1 stop11h 08m
Frontier
Deal found 3/17![Frontier logo]()
$111
This Kiwi.com deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” 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 5/1812:35 pm
PDX
- ORD
1 stop30h 02m
Frontier
Deal found 3/17![Frontier logo]()
$116
This Gotogate deal was found by Cheapflights users on 3/15. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/316:19 pm
PDX
- STL
1 stop24h 07m
Frontier
Deal found 3/15![Frontier logo]()
$116
This Kiwi.com deal was found by Cheapflights users on 3/14. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/141:48 pm
PDX
- ORD
2 stops25h 12m
Frontier
Deal found 3/14![Frontier logo]()
$117
This Kiwi.com deal was found by Cheapflights users on 3/14. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/141:48 pm
PDX
- MDW
2 stops30h 26m
Frontier
Deal found 3/14![Frontier logo]()
$118
This Alaska Airlines deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” 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 5/1510:37 am
PDX
- STL
Nonstop4h 00m
Alaska Airlines
Deal found 3/16![Alaska Airlines logo]()
$119
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 March 18, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $217 (American Airlines) |
One-way from | $94 (Kiwi.com) |
Popular in | November |
Cheapest in | January |
Average price | $389 |
Good round-trip deal | $304 or less |
Good one-way deal | $168 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 March 18, 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
Thu 4/16
3:16 pm-11:46 pm
1 stop6h 30m
Lambert-St Louis
Sat 4/18
5:21 pm-11:57 pm
1 stop8h 36m
$237
EugeneChicago
EUG - ORD
EUGORD
Eugene
Fri 5/1
8:38 pm-6:40 am
1 stop8h 02m
Chicago O'Hare Intl
Fri 5/8
8:48 pm-12:46 pm
1 stop17h 58m
$257
EugeneChicago
EUG - ORD
EUGORD
Eugene
Wed 5/27
11:20 am-10:55 pm
1 stop9h 35m
Chicago O'Hare Intl
Mon 6/1
6:15 pm-10:45 pm
1 stop6h 30m
$257
EugeneChicago
EUG - MDW
EUGMDW
Eugene
Tue 4/28
5:20 pm-5:00 am
1 stop9h 40m
Chicago Midway
Tue 5/5
6:30 am-10:45 am
1 stop6h 15m
$257
EugeneChicago
EUG - ORD
EUGORD
Eugene
Tue 4/14
6:30 am-9:18 pm
2 stops12h 48m
Chicago O'Hare Intl
Tue 4/21
6:00 pm-11:58 pm
1 stop7h 58m
$262
EugeneChicago
EUG - ORD
EUGORD
Eugene
Tue 4/28
6:30 am-6:04 pm
2 stops9h 34m
Chicago O'Hare Intl
Tue 5/5
7:10 pm-11:47 pm
1 stop6h 37m
$262
EugeneChicago
EUG - MDW
EUGMDW
Eugene
Wed 5/27
11:20 am-11:20 pm
2 stops10h 00m
Chicago Midway
Mon 6/1
5:15 pm-10:45 pm
1 stop7h 30m
$262
Quickest round-trip
PortlandChicago
PDX - MDW
PDXMDW
Portland
Sat 4/18
11:55 pm-5:50 am
Nonstop3h 55m
Chicago Midway
Sat 4/25
6:05 pm-8:25 pm
Nonstop4h 20m
$271
BoiseSt. Louis
BOI - STL
BOISTL
Boise Air Term. Gowen Fld
Tue 4/14
2:22 pm-11:59 pm
1 stop8h 37m
Lambert-St Louis
Wed 4/15
7:00 am-3:29 pm
1 stop9h 29m
$277
MedfordChicago
MFR - ORD
MFRORD
Medford
Sat 4/25
7:35 am-7:03 pm
1 stop9h 28m
Chicago O'Hare Intl
Tue 5/5
8:48 pm-12:52 pm
1 stop18h 04m
$277
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
PDX-MDW
PDX-ORD
BOI-STL
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
PDX-MDW
PDX-ORD
BOI-STL
What is the cheapest month to book a flight from Oregon to Illinois?
Currently, December is the cheapest month in which you can book a flight from Oregon to Illinois (average of $120). Flying from Oregon to Illinois in November is currently the most expensive (average of $237). 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 March 18, 2026.
It’s optimal to fly from Oregon to Illinois in the afternoon. By choosing this option you can save up to 37% on the cost of your flight, compared to a flight at noon.
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 March 14, 2026.
Travelers seeking maximum savings on their Oregon to Illinois flight should consider departing on Wednesday afternoons when fares are most often at their lowest. Sunday at noon flights should be avoided if possible as fares are typically the most expensive at this time.
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 March 18, 2026.
The most flights from USOR to USIL are scheduled on a Monday (20 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (11 on average).
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 March 18, 2026.
Peruse reviews from past customers who have flown with Southwest,Alaska Airlines, 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.
Entertainment
7.5
Comfort
8.0
Overall
8.0
Crew
8.6
Boarding
8.1
Food
7.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
Entertainment
7.5
Comfort
8.0
Overall
8.0
Crew
8.6
Boarding
8.1
Food
7.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
Entertainment
7.5
Comfort
8.0
Overall
8.0
Crew
8.6
Boarding
8.1
Food
7.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
Entertainment
7.5
Comfort
8.0
Overall
8.0
Crew
8.6
Boarding
8.1
Food
7.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
Entertainment
7.5
Comfort
8.0
Overall
8.0
Crew
8.6
Boarding
8.1
Food
7.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
Entertainment
7.5
Comfort
8.0
Overall
8.0
Crew
8.6
Boarding
8.1
Food
7.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
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.
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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 March 18, 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 8 airlines flying from Oregon to Illinois
Discover the top 8 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 March 18, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$93 | Average$184 | FlexibilityNo cancel fee | On-time65% | |
| Cheapest$96 | Average$238 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$99 | Average$352 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$125 | Average$317 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$176 | Average$453 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$179 | Average$411 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$201 | Average$451 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$209 | Average$395 | FlexibilityNo cancel fee | On-time75% |