$82+ 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 5/26. Fares are subject to change and may not be available on all flights or dates of travel.
PDX — ORD
May 30 — Jun 61
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 April 30, 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 April 30, 2026.
This CheapOair deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” 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 5/149:46 pm
PDX
- STL
1 stop20h 37m
Frontier
Wed 5/206:51 pm
STL
- PDX
1 stop17h 29m
Frontier
Deal found 4/29![Frontier logo]()
$216
This CheapOair deal was found by Cheapflights users on 4/26. Clicking the “Pick Dates” 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.
Sun 5/109:46 pm
PDX
- STL
1 stop20h 37m
Frontier
Wed 5/206:51 pm
STL
- PDX
1 stop17h 29m
Frontier
Deal found 4/26![Frontier logo]()
$221
This CheapOair deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/2312:35 pm
PDX
- STL
1 stop28h 48m
Frontier
Sat 5/306:30 pm
STL
- PDX
1 stop17h 50m
Frontier
Deal found 4/29![Frontier logo]()
$236
This CheapOair deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” 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 5/2812:35 pm
PDX
- STL
1 stop28h 48m
Frontier
Sun 5/318:08 pm
STL
- PDX
1 stop22h 38m
Frontier
Deal found 4/30![Frontier logo]()
$241
This Expedia deal was found by Cheapflights users on 4/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/111:15 am
PDX
- STL
1 stop6h 56m
Multiple Airlines
Sat 6/65:33 pm
STL
- PDX
Nonstop4h 17m
Multiple Airlines
Deal found 4/25![Multiple Airlines logo]()
$244
This CheapOair deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” 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 5/2112:35 pm
PDX
- STL
1 stop28h 48m
Frontier
Sat 5/236:30 pm
STL
- PDX
1 stop17h 50m
Frontier
Deal found 4/30![Frontier logo]()
$261
This Expedia deal was found by Cheapflights users on 4/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/411:15 am
PDX
- STL
1 stop6h 56m
Multiple Airlines
Sat 6/65:33 pm
STL
- PDX
Nonstop4h 17m
Multiple Airlines
Deal found 4/28![Multiple Airlines logo]()
$270
This Expedia deal was found by Cheapflights users on 4/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/2912:35 pm
PDX
- STL
1 stop28h 48m
Multiple Airlines
Fri 6/55:33 pm
STL
- PDX
Nonstop4h 17m
Multiple Airlines
Deal found 4/28![Multiple Airlines logo]()
$275
This CheapOair deal was found by Cheapflights users on 4/28. Clicking the “Pick Dates” 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 6/310:37 am
PDX
- STL
Nonstop4h 00m
Alaska Airlines
Sat 6/65:33 pm
STL
- PDX
Nonstop4h 17m
Alaska Airlines
Deal found 4/28![Alaska Airlines logo]()
$277
This Trip.com deal was found by Cheapflights users on 4/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/245:31 pm
PDX
- ORD
1 stop11h 03m
Frontier
Sat 5/308:46 pm
ORD
- PDX
1 stop17h 04m
Frontier
Deal found 4/25![Frontier logo]()
$280
This CheapOair deal was found by Cheapflights users on 4/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/215:16 pm
PDX
- ORD
1 stop25h 36m
Frontier
Fri 7/249:57 pm
ORD
- PDX
1 stop20h 56m
Frontier
Deal found 4/25![Frontier logo]()
$281
This CheapOair deal was found by Cheapflights users on 4/28. Clicking the “Pick Dates” 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 6/196:19 pm
PDX
- STL
1 stop17h 47m
Frontier
Mon 6/298:08 pm
STL
- PDX
1 stop22h 27m
Frontier
Deal found 4/28![Frontier logo]()
$281
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 April 30, 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 April 30, 2026.
This Delta deal was found by Cheapflights users on 4/26. Clicking the “Pick Dates” 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 5/213:10 pm
PDX
- STL
1 stop6h 11m
Delta
Wed 5/277:59 pm
STL
- PDX
1 stop5h 45m
Delta
Deal found 4/26![Delta logo]()
$303
This United Airlines deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” 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 5/282:27 pm
PDX
- ORD
Nonstop4h 13m
United Airlines
Wed 6/38:57 am
ORD
- PDX
Nonstop4h 41m
United Airlines
Deal found 4/29![United Airlines logo]()
$305
This Southwest deal was found by Cheapflights users on 4/25. Clicking the “Pick Dates” 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 6/99:20 pm
PDX
- MDW
1 stop9h 20m
Southwest
Tue 6/165:35 pm
MDW
- PDX
Nonstop4h 20m
Southwest
Deal found 4/25![Southwest logo]()
$315
This Alaska Airlines deal was found by Cheapflights users on 4/26. Clicking the “Pick Dates” 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 5/279:44 am
PDX
- ORD
1 stop7h 19m
Alaska Airlines
Mon 6/157:20 am
ORD
- PDX
Nonstop4h 25m
Alaska Airlines
Deal found 4/26![Alaska Airlines logo]()
$326
This United Airlines deal was found by Cheapflights users on 4/26. Clicking the “Pick Dates” 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 6/62:12 pm
PDX
- ORD
Nonstop4h 14m
United Airlines
Sat 6/137:56 pm
ORD
- PDX
Nonstop4h 35m
United Airlines
Deal found 4/26![United Airlines logo]()
$305
This Delta deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” 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 5/2711:12 pm
PDX
- STL
1 stop8h 17m
Delta
Tue 6/21:59 pm
STL
- PDX
1 stop10h 03m
Delta
Deal found 4/29![Delta logo]()
$317
This Southwest deal was found by Cheapflights users on 4/28. Clicking the “Pick Dates” 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 7/2111:30 pm
PDX
- MDW
Nonstop3h 50m
Southwest
Thu 7/305:00 am
MDW
- PDX
1 stop6h 55m
Southwest
Deal found 4/28![Southwest logo]()
$322
This Delta deal was found by Cheapflights users on 4/28. Clicking the “Pick Dates” 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 6/3011:47 am
PDX
- ORD
1 stop7h 38m
Delta
Tue 7/77:40 pm
ORD
- PDX
1 stop6h 04m
Delta
Deal found 4/28![Delta logo]()
$325
This United Airlines deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” 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 5/264:15 pm
PDX
- ORD
1 stop6h 29m
United Airlines
Wed 5/278:57 am
ORD
- PDX
Nonstop4h 41m
United Airlines
Deal found 4/29![United Airlines logo]()
$326
This Alaska Airlines deal was found by Cheapflights users on 4/28. Clicking the “Pick Dates” 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 5/231:53 pm
RDM
- ORD
1 stop8h 06m
Alaska Airlines
Sun 5/247:40 am
ORD
- RDM
1 stop7h 19m
Alaska Airlines
Deal found 4/28![Alaska Airlines logo]()
$368
This Southwest deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” 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 7/223:00 pm
BOI
- MDW
1 stop7h 35m
Southwest
Sat 8/82:05 pm
MDW
- BOI
1 stop8h 55m
Southwest
Deal found 4/29![Southwest logo]()
$335
This United Airlines deal was found by Cheapflights users on 4/28. Clicking the “Pick Dates” 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 6/45:00 pm
PDX
- ORD
Nonstop4h 13m
United Airlines
Mon 6/87:05 am
ORD
- PDX
Nonstop4h 34m
United Airlines
Deal found 4/28![United Airlines logo]()
$327
This Delta deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” 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 7/226:15 am
PDX
- STL
1 stop6h 58m
Delta
Tue 7/282:30 pm
STL
- PDX
1 stop5h 48m
Delta
Deal found 4/29![Delta logo]()
$329
This Alaska Airlines deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” 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 7/304:00 pm
RDM
- ORD
1 stop11h 00m
Alaska Airlines
Wed 8/58:05 pm
ORD
- RDM
1 stop14h 59m
Alaska Airlines
Deal found 4/29![Alaska Airlines logo]()
$369
This Southwest deal was found by Cheapflights users on 4/28. Clicking the “Pick Dates” 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 6/81:05 pm
PDX
- MDW
1 stop8h 20m
Southwest
Fri 6/122:30 pm
MDW
- PDX
1 stop7h 30m
Southwest
Deal found 4/28![Southwest logo]()
$347
This United Airlines deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/1710:40 pm
PDX
- ORD
Nonstop4h 05m
United Airlines
Sun 7/197:00 am
ORD
- PDX
Nonstop4h 34m
United Airlines
Deal found 4/27![United Airlines logo]()
$327
This Delta deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” 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 6/2310:29 am
BOI
- MDW
1 stop6h 49m
Delta
Tue 6/301:49 pm
MDW
- BOI
1 stop8h 06m
Delta
Deal found 4/29![Delta logo]()
$335
This Alaska Airlines deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” 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 5/2110:37 am
PDX
- STL
Nonstop4h 00m
Alaska Airlines
Wed 5/275:33 pm
STL
- PDX
Nonstop4h 17m
Alaska Airlines
Deal found 4/27![Alaska Airlines logo]()
$378
This Southwest deal was found by Cheapflights users on 4/25. Clicking the “Pick Dates” 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 5/305:15 pm
EUG
- MDW
1 stop9h 45m
Southwest
Mon 6/16:00 am
MDW
- EUG
1 stop6h 30m
Southwest
Deal found 4/25![Southwest logo]()
$349
This United Airlines deal was found by Cheapflights users on 4/25. Clicking the “Pick Dates” 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 5/1811:55 pm
PDX
- ORD
Nonstop4h 05m
United Airlines
Wed 5/271:29 pm
ORD
- PDX
Nonstop4h 27m
United Airlines
Deal found 4/25![United Airlines logo]()
$336
This Delta deal was found by Cheapflights users on 4/25. Clicking the “Pick Dates” 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 7/211:25 pm
PDX
- ORD
1 stop7h 53m
Delta
Mon 7/276:55 am
ORD
- PDX
1 stop6h 46m
Delta
Deal found 4/25![Delta logo]()
$336
This Southwest deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” 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 7/215:55 pm
EUG
- MDW
1 stop9h 05m
Southwest
Mon 7/275:15 am
MDW
- EUG
1 stop6h 20m
Southwest
Deal found 4/27![Southwest logo]()
$349
This United Airlines deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” 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 8/2212:25 pm
EUG
- ORD
Nonstop4h 09m
United Airlines
Sun 9/66:00 am
ORD
- EUG
1 stop7h 58m
United Airlines
Deal found 4/27![United Airlines logo]()
$339
This Delta deal was found by Cheapflights users on 4/26. Clicking the “Pick Dates” 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 7/810:29 am
BOI
- MDW
1 stop6h 49m
Delta
Tue 7/141:49 pm
MDW
- BOI
2 stops11h 16m
Delta
Deal found 4/26![Delta logo]()
$340
This Alaska Airlines deal was found by Cheapflights users on 4/26. Clicking the “Pick Dates” 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 7/253:52 pm
MFR
- ORD
1 stop11h 08m
Alaska Airlines
Wed 8/56:00 am
ORD
- MFR
1 stop8h 50m
Alaska Airlines
Deal found 4/26![Alaska Airlines logo]()
$413
This Southwest deal was found by Cheapflights users on 4/26. Clicking the “Pick Dates” 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 5/275:20 pm
EUG
- MDW
1 stop9h 40m
Southwest
Wed 6/310:40 am
MDW
- EUG
1 stop8h 00m
Southwest
Deal found 4/26![Southwest logo]()
$349
This Delta deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” 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 5/285:20 am
BOI
- ORD
2 stops11h 45m
Delta
Tue 6/27:12 am
ORD
- BOI
1 stop8h 29m
Delta
Deal found 4/29![Delta logo]()
$340
This Alaska Airlines deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” 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 7/254:00 pm
EUG
- ORD
1 stop11h 00m
Alaska Airlines
Sat 8/17:17 pm
ORD
- EUG
1 stop6h 42m
Alaska Airlines
Deal found 4/29![Alaska Airlines logo]()
$417
This Southwest deal was found by Cheapflights users on 4/25. Clicking the “Pick Dates” 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 5/315:10 pm
EUG
- MDW
1 stop9h 50m
Southwest
Tue 6/210:40 am
MDW
- EUG
1 stop8h 00m
Southwest
Deal found 4/25![Southwest logo]()
$354
This United Airlines deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” 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 5/201:07 pm
EUG
- ORD
Nonstop3h 52m
United Airlines
Tue 5/268:53 am
ORD
- EUG
Nonstop4h 44m
United Airlines
Deal found 4/27![United Airlines logo]()
$372
Last-minute flights from Oregon to IllinoisDiscover last-minute flight deals from Oregon to Illinois. Data last updated April 30, 2026 and is based on user searches.
Discover last-minute flight deals from Oregon to Illinois. Data last updated April 30, 2026 and is based on user searches.
This CheapOair deal was found by Cheapflights users on 4/26. Clicking the “Pick Dates” 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.
Sun 5/109:46 pm
PDX
- STL
1 stop20h 37m
Frontier
Wed 5/206:51 pm
STL
- PDX
1 stop17h 29m
Frontier
Deal found 4/26![Frontier logo]()
$221
This CheapOair deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” 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 5/149:46 pm
PDX
- STL
1 stop20h 37m
Frontier
Wed 5/206:51 pm
STL
- PDX
1 stop17h 29m
Frontier
Deal found 4/29![Frontier logo]()
$216
This CheapOair deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” 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 5/2112:35 pm
PDX
- STL
1 stop28h 48m
Frontier
Sat 5/236:30 pm
STL
- PDX
1 stop17h 50m
Frontier
Deal found 4/30![Frontier logo]()
$261
This CheapOair deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/2312:35 pm
PDX
- STL
1 stop28h 48m
Frontier
Sat 5/306:30 pm
STL
- PDX
1 stop17h 50m
Frontier
Deal found 4/29![Frontier logo]()
$236
This Trip.com deal was found by Cheapflights users on 4/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/245:31 pm
PDX
- ORD
1 stop11h 03m
Frontier
Sat 5/308:46 pm
ORD
- PDX
1 stop17h 04m
Frontier
Deal found 4/25![Frontier logo]()
$280
This Trip.com deal was found by Cheapflights users on 4/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/247:00 am
PDX
- ORD
Nonstop4h 22m
Multiple Airlines
Sat 5/308:46 pm
ORD
- PDX
1 stop17h 04m
Multiple Airlines
Deal found 4/25![Multiple Airlines logo]()
$281
This Super.com deal was found by Cheapflights users on 4/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/265:46 pm
PDX
- ORD
1 stop24h 46m
Frontier
Sat 5/308:46 pm
ORD
- PDX
1 stop17h 04m
Frontier
Deal found 4/25![Frontier logo]()
$282
This CheapOair deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” 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 5/2812:35 pm
PDX
- STL
1 stop28h 48m
Frontier
Sun 5/318:08 pm
STL
- PDX
1 stop22h 38m
Frontier
Deal found 4/30![Frontier logo]()
$241
This CheapOair deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” 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 5/2812:35 pm
PDX
- STL
1 stop28h 48m
Frontier
Mon 6/18:08 pm
STL
- PDX
1 stop22h 53m
Frontier
Deal found 4/27![Frontier logo]()
$281
This Kiwi.com deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” 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 5/2812:35 pm
PDX
- ORD
2 stops17h 20m
Frontier
Sat 5/308:46 pm
ORD
- PDX
1 stop17h 04m
Frontier
Deal found 4/27![Frontier logo]()
$284
This Expedia deal was found by Cheapflights users on 4/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/2912:35 pm
PDX
- STL
1 stop28h 48m
Multiple Airlines
Fri 6/55:33 pm
STL
- PDX
Nonstop4h 17m
Multiple Airlines
Deal found 4/28![Multiple Airlines logo]()
$275
This Alaska Airlines deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” 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 5/2910:37 am
PDX
- STL
Nonstop4h 00m
Alaska Airlines
Sat 5/305:33 pm
STL
- PDX
Nonstop4h 17m
Alaska Airlines
Deal found 4/27![Alaska Airlines logo]()
$283
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 April 30, 2026.
Search for one-way flight options from Oregon to Illinois. Find affordable one-way fares based on user searches. Data last updated April 30, 2026.
This Kiwi.com deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” 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 5/265:46 pm
PDX
- STL
1 stop23h 37m
Frontier
Deal found 4/29![Frontier logo]()
$82
This Kiwi.com deal was found by Cheapflights users on 4/26. Clicking the “Pick Dates” 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 5/261:25 pm
BOI
- ORD
1 stop30h 07m
Frontier
Deal found 4/26![Frontier logo]()
$96
This Frontier deal was found by Cheapflights users on 4/25. Clicking the “Pick Dates” 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 6/91:25 pm
BOI
- ORD
1 stop6h 18m
Frontier
Deal found 4/25![Frontier logo]()
$105
This Frontier deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” 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.
Fri 5/2911:15 am
PDX
- STL
1 stop6h 56m
Frontier
Deal found 4/29![Frontier logo]()
$105
This Trip.com deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/118:46 pm
PDX
- STL
1 stop19h 20m
Frontier
Deal found 4/27![Frontier logo]()
$109
This CheapOair deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 6/612:35 pm
PDX
- STL
1 stop28h 48m
Frontier
Deal found 4/29![Frontier logo]()
$117
This Priceline deal was found by Cheapflights users on 4/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/241:25 pm
BOI
- ORD
1 stop6h 07m
Frontier
Deal found 4/26![Frontier logo]()
$125
This Kiwi.com deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” 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 5/2512:35 pm
PDX
- STL
1 stop28h 48m
Frontier
Deal found 4/29![Frontier logo]()
$129
This Kiwi.com deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” 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 5/2312:35 pm
PDX
- STL
2 stops26h 58m
Frontier
Deal found 4/29![Frontier logo]()
$131
This Trip.com deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/79:46 pm
PDX
- STL
1 stop20h 37m
Frontier
Deal found 4/29![Frontier logo]()
$134
This Kiwi.com deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/2412:35 pm
PDX
- STL
2 stops18h 20m
Frontier
Deal found 4/29![Frontier logo]()
$136
This CheapOair deal was found by Cheapflights users on 4/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/3012:35 pm
PDX
- STL
1 stop28h 48m
Frontier
Deal found 4/26![Frontier logo]()
$137
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 April 30, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $216 (CheapOair) |
One-way from | $82 (Kiwi.com) |
Popular in | November |
Cheapest in | January |
Average price | $379 |
Good round-trip deal | $371 or less |
Good one-way deal | $143 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 April 30, 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 5/21
3:10 pm-11:21 pm
1 stop6h 11m
Lambert-St Louis
Wed 5/27
7:59 pm-11:44 pm
1 stop5h 45m
$303
PortlandChicago
PDX - ORD
PDXORD
Portland
Thu 5/28
2:27 pm-8:40 pm
Nonstop4h 13m
Chicago O'Hare Intl
Wed 6/3
8:57 am-11:38 am
Nonstop4h 41m
$305
PortlandChicago
PDX - ORD
PDXORD
Portland
Sat 6/6
2:12 pm-8:26 pm
Nonstop4h 14m
Chicago O'Hare Intl
Sat 6/13
7:56 pm-10:31 pm
Nonstop4h 35m
$305
PortlandChicago
PDX - MDW
PDXMDW
Portland
Tue 6/9
9:20 pm-8:40 am
1 stop9h 20m
Chicago Midway
Tue 6/16
5:35 pm-7:55 pm
Nonstop4h 20m
$315
PortlandSt. Louis
PDX - STL
PDXSTL
Portland
Wed 5/27
11:12 pm-9:29 am
1 stop8h 17m
Lambert-St Louis
Tue 6/2
1:59 pm-10:02 pm
1 stop10h 03m
$317
PortlandChicago
PDX - MDW
PDXMDW
Portland
Tue 7/21
11:30 pm-5:20 am
Nonstop3h 50m
Chicago Midway
Thu 7/30
5:00 am-9:55 am
1 stop6h 55m
$322
PortlandChicago
PDX - ORD
PDXORD
Portland
Tue 6/30
11:47 am-9:25 pm
1 stop7h 38m
Chicago O'Hare Intl
Tue 7/7
7:40 pm-11:44 pm
1 stop6h 04m
$325
PortlandChicago
PDX - ORD
PDXORD
Portland
Wed 5/27
9:44 am-7:03 pm
1 stop7h 19m
Chicago O'Hare Intl
Mon 6/15
7:20 am-9:45 am
Nonstop4h 25m
$326
PortlandChicago
PDX - ORD
PDXORD
Portland
Tue 5/26
4:15 pm-12:44 am
1 stop6h 29m
Chicago O'Hare Intl
Wed 5/27
8:57 am-11:38 am
Nonstop4h 41m
$326
PortlandChicago
PDX - ORD
PDXORD
Portland
Thu 6/4
5:00 pm-11:13 pm
Nonstop4h 13m
Chicago O'Hare Intl
Mon 6/8
7:05 am-9:39 am
Nonstop4h 34m
$327
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-ORD
BOI-ORD
PDX-MDW
RDM-ORD
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-ORD
BOI-ORD
PDX-MDW
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 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 $844). 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 April 30, 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 April 25, 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 afternoons 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 April 30, 2026.
The most flights from USOR to USIL are scheduled on a Wednesday (24 on average). You will have fewer flight options on Thursday, which is when the least amount of flights are scheduled (6 on average).
How much does it cost to fly round-trip from Oregon to Illinois?
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 April 30, 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.
Boarding
8.1
Crew
8.6
Food
7.0
Comfort
8.0
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Boarding
8.1
Crew
8.6
Food
7.0
Comfort
8.0
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Boarding
8.1
Crew
8.6
Food
7.0
Comfort
8.0
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Boarding
8.1
Crew
8.6
Food
7.0
Comfort
8.0
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Boarding
8.1
Crew
8.6
Food
7.0
Comfort
8.0
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Boarding
8.1
Crew
8.6
Food
7.0
Comfort
8.0
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
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 April 30, 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 April 30, 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$349 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$113 | Average$313 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$170 | Average$447 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$179 | Average$387 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$204 | Average$453 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$207 | Average$388 | FlexibilityNo cancel fee | On-time75% |