$104+ Cheap flights from Idaho 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 8/12. Fares are subject to change and may not be available on all flights or dates of travel.
BOI — ORD
Jul 10 — Jul 171
Round-trip
1 adult, Economy
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Cheapest flights from Idaho to IllinoisExplore the most affordable flight options available from Idaho to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 10, 2026.
Explore the most affordable flight options available from Idaho to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 10, 2026.
This American Airlines deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/122:27 pm
GEG
- ORD
Nonstop4h 01m
American Airlines
Wed 9/211:30 am
ORD
- GEG
Nonstop4h 07m
American Airlines
Deal found 6/8![American Airlines logo]()
$213
This Delta deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/11:00 pm
GEG
- ORD
1 stop8h 29m
Delta
Tue 9/226:15 am
ORD
- GEG
1 stop8h 38m
Delta
Deal found 6/9![Delta logo]()
$233
This Delta deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/15:15 am
GEG
- ORD
2 stops11h 04m
Delta
Wed 9/237:25 am
ORD
- GEG
1 stop10h 14m
Delta
Deal found 6/9![Delta logo]()
$238
This Delta deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/127:05 am
GEG
- ORD
2 stops12h 25m
Delta
Wed 9/21:50 pm
ORD
- GEG
2 stops11h 19m
Delta
Deal found 6/8![Delta logo]()
$243
This Delta deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/55:15 am
GEG
- ORD
1 stop6h 08m
Delta
Tue 9/226:15 am
ORD
- GEG
1 stop8h 38m
Delta
Deal found 6/9![Delta logo]()
$256
This American Airlines deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/282:09 pm
GEG
- ORD
Nonstop4h 06m
American Airlines
Wed 9/3011:10 am
ORD
- GEG
Nonstop4h 09m
American Airlines
Deal found 6/9![American Airlines logo]()
$258
This Delta deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/115:15 am
GEG
- ORD
2 stops11h 04m
Delta
Sat 8/158:28 am
ORD
- GEG
1 stop6h 30m
Delta
Deal found 6/9![Delta logo]()
$261
This Delta deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/296:00 am
BOI
- STL
1 stop6h 33m
Delta
Tue 9/296:55 pm
STL
- BOI
1 stop6h 03m
Delta
Deal found 6/8![Delta logo]()
$263
This Southwest deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/286:00 am
GEG
- MDW
Nonstop3h 30m
Southwest
Wed 9/306:40 am
MDW
- GEG
1 stop5h 35m
Southwest
Deal found 6/9![Southwest logo]()
$269
This Southwest deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/93:40 pm
BOI
- STL
1 stop5h 55m
Southwest
Tue 9/157:00 am
STL
- BOI
2 stops7h 40m
Southwest
Deal found 6/9![Southwest logo]()
$270
This American Airlines deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/161:58 pm
IDA
- ORD
Nonstop3h 37m
American Airlines
Tue 9/2210:45 am
ORD
- IDA
Nonstop3h 43m
American Airlines
Deal found 6/9![American Airlines logo]()
$271
This Delta deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/1912:36 pm
GEG
- MDW
1 stop8h 00m
Delta
Mon 8/246:05 am
MDW
- GEG
1 stop7h 16m
Delta
Deal found 6/8![Delta logo]()
$278
Best flights from Idaho to IllinoisDiscover carefully curated flight deals from Idaho to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated June 10, 2026.
Discover carefully curated flight deals from Idaho to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated June 10, 2026.
This Delta deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/127:05 am
GEG
- ORD
2 stops12h 25m
Delta
Wed 9/21:50 pm
ORD
- GEG
2 stops11h 19m
Delta
Deal found 6/8![Delta logo]()
$243
This American Airlines deal was found by Cheapflights users on 6/5. Clicking the “Pick Dates” 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 10/141:43 pm
IDA
- ORD
Nonstop3h 17m
American Airlines
Wed 10/219:40 am
ORD
- IDA
Nonstop3h 40m
American Airlines
Deal found 6/5![American Airlines logo]()
$271
This Southwest deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/191:55 pm
GEG
- MDW
1 stop6h 55m
Southwest
Tue 8/254:45 pm
MDW
- GEG
1 stop7h 20m
Southwest
Deal found 6/8![Southwest logo]()
$294
This CheapOair deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/21:25 pm
BOI
- STL
1 stop28h 28m
Frontier
Wed 7/88:08 pm
STL
- BOI
1 stop17h 21m
Frontier
Deal found 6/9![Frontier logo]()
$299
This United Airlines deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/45:57 pm
IDA
- ORD
1 stop5h 00m
United Airlines
Tue 11/105:00 am
ORD
- IDA
1 stop5h 28m
United Airlines
Deal found 6/8![United Airlines logo]()
$306
This Alaska Airlines deal was found by Cheapflights users on 6/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/311:46 pm
IDA
- ORD
1 stop9h 13m
Alaska Airlines
Wed 11/43:59 pm
ORD
- IDA
1 stop8h 43m
Alaska Airlines
Deal found 6/7![Alaska Airlines logo]()
$310
This Delta deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/187:54 pm
GEG
- ORD
2 stops10h 36m
Delta
Tue 8/252:00 pm
ORD
- GEG
2 stops9h 16m
Delta
Deal found 6/9![Delta logo]()
$315
This Southwest deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/146:55 am
GEG
- MDW
2 stops8h 05m
Southwest
Mon 9/218:50 pm
MDW
- GEG
Nonstop3h 50m
Southwest
Deal found 6/8![Southwest logo]()
$319
This Alaska Airlines deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/292:01 pm
IDA
- ORD
1 stop8h 58m
Alaska Airlines
Sat 9/53:43 pm
ORD
- IDA
1 stop8h 13m
Alaska Airlines
Deal found 6/9![Alaska Airlines logo]()
$329
This United Airlines deal was found by Cheapflights users on 6/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/284:05 pm
IDA
- ORD
1 stop5h 41m
United Airlines
Mon 10/55:00 am
ORD
- IDA
1 stop5h 53m
United Airlines
Deal found 6/5![United Airlines logo]()
$329
This Delta deal was found by Cheapflights users on 6/5. Clicking the “Pick Dates” 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 10/146:00 am
IDA
- ORD
1 stop5h 25m
Delta
Wed 10/2111:30 am
ORD
- IDA
2 stops11h 49m
Delta
Deal found 6/5![Delta logo]()
$316
This Southwest deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/133:50 pm
BOI
- MDW
1 stop6h 25m
Southwest
Fri 8/2111:40 am
MDW
- BOI
Nonstop3h 30m
Southwest
Deal found 6/9![Southwest logo]()
$333
This United Airlines deal was found by Cheapflights users on 6/6. Clicking the “Pick Dates” 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 8/2512:24 pm
BOI
- ORD
Nonstop3h 39m
United Airlines
Tue 9/15:51 pm
ORD
- BOI
1 stop5h 49m
United Airlines
Deal found 6/6![United Airlines logo]()
$335
This American Airlines deal was found by Cheapflights users on 6/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/113:41 pm
JAC
- ORD
Nonstop3h 29m
American Airlines
Sun 9/139:45 am
ORD
- JAC
Nonstop3h 22m
American Airlines
Deal found 6/6![American Airlines logo]()
$374
This Expedia deal was found by Cheapflights users on 6/5. Clicking the “Pick Dates” 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.
Wed 7/154:14 pm
IDA
- ORD
1 stop11h 46m
Alaska Airlines
Fri 7/177:20 am
ORD
- IDA
1 stop6h 46m
Alaska Airlines
Deal found 6/5![Alaska Airlines logo]()
$355
This Delta deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/93:05 pm
GEG
- ORD
1 stop6h 41m
Delta
Tue 10/137:00 am
ORD
- GEG
1 stop9h 45m
Delta
Deal found 6/8![Delta logo]()
$324
This Southwest deal was found by Cheapflights users on 6/5. Clicking the “Pick Dates” 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 7/1511:30 am
BOI
- MDW
1 stop8h 50m
Southwest
Wed 7/225:25 am
MDW
- BOI
1 stop6h 40m
Southwest
Deal found 6/5![Southwest logo]()
$335
This United Airlines deal was found by Cheapflights users on 6/5. Clicking the “Pick Dates” 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 7/112:40 pm
BOI
- ORD
1 stop7h 09m
United Airlines
Thu 7/168:40 am
ORD
- BOI
Nonstop3h 52m
United Airlines
Deal found 6/5![United Airlines logo]()
$355
This Alaska Airlines deal was found by Cheapflights users on 6/6. Clicking the “Pick Dates” 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 10/97:43 pm
GEG
- ORD
1 stop8h 37m
Alaska Airlines
Tue 10/132:21 pm
ORD
- GEG
1 stop9h 19m
Alaska Airlines
Deal found 6/6![Alaska Airlines logo]()
$357
This Southwest deal was found by Cheapflights users on 6/6. Clicking the “Pick Dates” 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 7/147:10 am
BOI
- MDW
Nonstop3h 20m
Southwest
Tue 7/216:10 am
MDW
- BOI
1 stop8h 15m
Southwest
Deal found 6/6![Southwest logo]()
$335
This Delta deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/2111:30 pm
BOI
- MLI
1 stop9h 56m
Delta
Thu 10/295:55 am
MLI
- BOI
1 stop7h 44m
Delta
Deal found 6/9![Delta logo]()
$339
This American Airlines deal was found by Cheapflights users on 6/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/111:55 pm
BOI
- STL
2 stops8h 47m
American Airlines
Tue 8/1812:45 pm
STL
- BOI
2 stops10h 55m
American Airlines
Deal found 6/7![American Airlines logo]()
$417
This Delta deal was found by Cheapflights users on 6/5. Clicking the “Pick Dates” 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 10/711:30 pm
BOI
- MLI
1 stop9h 56m
Delta
Sat 10/175:55 am
MLI
- BOI
1 stop7h 44m
Delta
Deal found 6/5![Delta logo]()
$339
This Alaska Airlines deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/2412:42 pm
GEG
- ORD
1 stop14h 18m
Alaska Airlines
Mon 7/278:20 pm
ORD
- GEG
1 stop14h 06m
Alaska Airlines
Deal found 6/8![Alaska Airlines logo]()
$387
This Southwest deal was found by Cheapflights users on 6/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/228:00 am
GEG
- MDW
1 stop7h 35m
Southwest
Thu 8/278:50 pm
MDW
- GEG
Nonstop3h 50m
Southwest
Deal found 6/5![Southwest logo]()
$354
This United Airlines deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/15:44 pm
BOI
- STL
1 stop4h 56m
United Airlines
Wed 9/28:42 am
STL
- BOI
1 stop7h 49m
United Airlines
Deal found 6/9![United Airlines logo]()
$393
This American Airlines deal was found by Cheapflights users on 6/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/31:57 pm
BOI
- STL
1 stop9h 01m
American Airlines
Fri 7/107:07 am
STL
- BOI
1 stop8h 39m
American Airlines
Deal found 6/5![American Airlines logo]()
$435
This Delta deal was found by Cheapflights users on 6/5. Clicking the “Pick Dates” 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 8/55:15 am
GEG
- ORD
2 stops11h 04m
Delta
Wed 8/197:25 am
ORD
- GEG
1 stop10h 11m
Delta
Deal found 6/5![Delta logo]()
$346
This Southwest deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/2912:35 pm
BOI
- STL
2 stops8h 05m
Southwest
Tue 10/68:35 am
STL
- BOI
2 stops8h 25m
Southwest
Deal found 6/8![Southwest logo]()
$356
This United Airlines deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/31:45 pm
GEG
- STL
2 stops8h 49m
United Airlines
Wed 11/41:27 pm
STL
- GEG
2 stops12h 11m
United Airlines
Deal found 6/9![United Airlines logo]()
$399
Last-minute flights from Idaho to IllinoisDiscover last-minute flight deals from Idaho to Illinois. Data last updated June 10, 2026 and is based on user searches.
Discover last-minute flight deals from Idaho to Illinois. Data last updated June 10, 2026 and is based on user searches.
This Expedia deal was found by Cheapflights users on 6/5. Clicking the “Pick Dates” 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 6/2912:31 pm
GEG
- ORD
1 stop6h 12m
Multiple Airlines
Sat 7/47:20 am
ORD
- GEG
1 stop6h 25m
Multiple Airlines
Deal found 6/5![Multiple Airlines logo]()
$333
This American Airlines deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/12:01 pm
GEG
- ORD
Nonstop3h 58m
American Airlines
Sat 7/411:00 am
ORD
- GEG
Nonstop4h 09m
American Airlines
Deal found 6/9![American Airlines logo]()
$323
This Frontier deal was found by Cheapflights users on 6/6. Clicking the “Pick Dates” 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 7/21:25 pm
BOI
- STL
1 stop28h 28m
Frontier
Wed 7/88:08 pm
STL
- BOI
1 stop17h 21m
Frontier
Deal found 6/6![Frontier logo]()
$289
This United Airlines deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/34:14 pm
IDA
- ORD
1 stop5h 35m
United Airlines
Sun 7/55:00 am
ORD
- IDA
1 stop5h 50m
United Airlines
Deal found 6/9![United Airlines logo]()
$329
This Southwest deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/87:10 am
BOI
- MDW
Nonstop3h 20m
Southwest
Tue 7/146:40 pm
MDW
- BOI
1 stop6h 50m
Southwest
Deal found 6/8![Southwest logo]()
$335
This Priceline deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/152:11 pm
JAC
- ORD
1 stop8h 25m
Alaska Airlines
Wed 7/227:20 am
ORD
- JAC
1 stop7h 11m
Alaska Airlines
Deal found 6/9![Alaska Airlines logo]()
$339
This Southwest deal was found by Cheapflights users on 6/5. Clicking the “Pick Dates” 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 7/155:30 am
BOI
- MDW
2 stops8h 05m
Southwest
Wed 7/226:40 pm
MDW
- BOI
1 stop6h 50m
Southwest
Deal found 6/5![Southwest logo]()
$340
This American Airlines deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/212:29 pm
GEG
- ORD
Nonstop4h 03m
American Airlines
Tue 7/2811:30 am
ORD
- GEG
Nonstop4h 09m
American Airlines
Deal found 6/9![American Airlines logo]()
$311
This Priceline deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/217:45 pm
GEG
- ORD
1 stop8h 35m
Alaska Airlines
Tue 7/286:00 am
ORD
- GEG
1 stop8h 29m
Alaska Airlines
Deal found 6/8![Alaska Airlines logo]()
$315
This Delta deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/215:25 am
GEG
- ORD
1 stop6h 03m
Delta
Tue 7/282:07 pm
ORD
- GEG
2 stops10h 59m
Delta
Deal found 6/9![Delta logo]()
$336
This American Airlines deal was found by Cheapflights users on 6/5. Clicking the “Pick Dates” 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 7/292:29 pm
GEG
- ORD
Nonstop4h 03m
American Airlines
Tue 8/411:30 am
ORD
- GEG
Nonstop4h 09m
American Airlines
Deal found 6/5![American Airlines logo]()
$332
This CheapOair deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/301:24 pm
BOI
- STL
1 stop4h 59m
Frontier
Sat 8/88:08 pm
STL
- BOI
1 stop17h 21m
Frontier
Deal found 6/9![Frontier logo]()
$313
One-way flights from Idaho to IllinoisSearch for one-way flight options from Idaho to Illinois. Find affordable one-way fares based on user searches. Data last updated June 10, 2026.
Search for one-way flight options from Idaho to Illinois. Find affordable one-way fares based on user searches. Data last updated June 10, 2026.
This American Airlines deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/123:16 pm
BOI
- ORD
Nonstop3h 51m
American Airlines
Deal found 6/9![American Airlines logo]()
$104
This American Airlines deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/302:09 pm
GEG
- ORD
Nonstop4h 06m
American Airlines
Deal found 6/9![American Airlines logo]()
$107
This Delta deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/52:02 pm
BOI
- MDW
1 stop7h 34m
Delta
Deal found 6/9![Delta logo]()
$114
This Delta deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/43:29 pm
BOI
- ORD
1 stop7h 00m
Delta
Deal found 6/8![Delta logo]()
$114
This Southwest deal was found by Cheapflights users on 6/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/44:55 pm
GEG
- MDW
1 stop10h 05m
Southwest
Deal found 6/7![Southwest logo]()
$117
This Delta deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/86:30 am
GEG
- ORD
1 stop9h 00m
Delta
Deal found 6/8![Delta logo]()
$117
This Delta deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/96:00 am
BOI
- MDW
2 stops11h 05m
Delta
Deal found 6/9![Delta logo]()
$119
This Delta deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/98:40 am
BOI
- ORD
2 stops12h 18m
Delta
Deal found 6/8![Delta logo]()
$119
This Delta deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/305:40 pm
GEG
- ORD
2 stops12h 22m
Delta
Deal found 6/8![Delta logo]()
$122
This American Airlines deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/53:21 pm
BOI
- ORD
Nonstop3h 51m
American Airlines
Deal found 6/8![American Airlines logo]()
$126
This American Airlines deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/52:27 pm
GEG
- ORD
Nonstop4h 01m
American Airlines
Deal found 6/8![American Airlines logo]()
$130
This Frontier deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/141:24 pm
BOI
- ORD
1 stop6h 28m
Frontier
Deal found 6/9![Frontier logo]()
$135
Find flight deals from Idaho to Illinois
Keep the following information in mind while searching for Idaho to Illinois flight deals. Data was last updated June 10, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $213 (American Airlines) |
One-way from | $104 (American Airlines) |
Popular in | March |
Cheapest in | February |
Average price | $411 |
Good round-trip deal | $417 or less |
Good one-way deal | $236 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Idaho 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 10, 2026.
Use the filters below to find and compare flights from Idaho to Illinois that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
SpokaneChicago
GEG - ORD
GEGORD
Spokane
Wed 8/12
7:05 am-9:30 pm
2 stops12h 25m
Chicago O'Hare Intl
Wed 9/2
1:50 pm-11:09 pm
2 stops11h 19m
$243
Idaho FallsChicago
IDA - ORD
IDAORD
Idaho Falls Fanning Field
Wed 10/14
1:43 pm-6:00 pm
Nonstop3h 17m
Chicago O'Hare Intl
Wed 10/21
9:40 am-12:20 pm
Nonstop3h 40m
$271
SpokaneChicago
GEG - MDW
GEGMDW
Spokane
Wed 8/19
1:55 pm-10:50 pm
1 stop6h 55m
Chicago Midway
Tue 8/25
4:45 pm-10:05 pm
1 stop7h 20m
$294
BoiseSt. Louis
BOI - STL
BOISTL
Boise Air Term. Gowen Fld
Thu 7/2
1:25 pm-6:53 pm
1 stop28h 28m
Lambert-St Louis
Wed 7/8
8:08 pm-12:29 pm
1 stop17h 21m
$299
Idaho FallsChicago
IDA - ORD
IDAORD
Idaho Falls Fanning Field
Wed 11/4
5:57 pm-11:57 pm
1 stop5h 00m
Chicago O'Hare Intl
Tue 11/10
5:00 am-9:28 am
1 stop5h 28m
$306
Idaho FallsChicago
IDA - ORD
IDAORD
Idaho Falls Fanning Field
Sat 10/31
1:46 pm-11:59 pm
1 stop9h 13m
Chicago O'Hare Intl
Wed 11/4
3:59 pm-11:42 pm
1 stop8h 43m
$310
SpokaneChicago
GEG - ORD
GEGORD
Spokane
Tue 8/18
7:54 pm-8:30 am
2 stops10h 36m
Chicago O'Hare Intl
Tue 8/25
2:00 pm-9:16 pm
2 stops9h 16m
$315
Idaho FallsChicago
IDA - ORD
IDAORD
Idaho Falls Fanning Field
Wed 10/14
6:00 am-12:25 pm
1 stop5h 25m
Chicago O'Hare Intl
Wed 10/21
11:30 am-10:19 pm
2 stops11h 49m
$316
SpokaneChicago
GEG - MDW
GEGMDW
Spokane
Mon 9/14
6:55 am-5:00 pm
2 stops8h 05m
Chicago Midway
Mon 9/21
8:50 pm-10:40 pm
Nonstop3h 50m
$319
SpokaneChicago
GEG - ORD
GEGORD
Spokane
Fri 10/9
3:05 pm-11:46 pm
1 stop6h 41m
Chicago O'Hare Intl
Tue 10/13
7:00 am-2:45 pm
1 stop9h 45m
$324
Showing 1-10 of 60 resultsSorted by cheapest first
Best time to book a flight from Idaho to Illinois
Have a flexible travel schedule? Discover the best time to fly to Illinois from Idaho with our price prediction graph.
BOI-MDW
GEG-ORD
JAC-ORD
GEG-STL
BOI-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 Idaho to Illinois
USID-USIL
BOI-MDW
GEG-ORD
JAC-ORD
GEG-STL
What is the cheapest month to book a flight from Idaho to Illinois?
Currently, July is the cheapest month in which you can book a flight from Idaho to Illinois (average of $87). Flying from Idaho to Illinois in March is currently the most expensive (average of $268). 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 ID to IL?
Find hourly flight availability from Idaho 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 10, 2026.
It’s optimal to fly from Idaho to Illinois in the afternoon. By choosing this option you can save up to 24% on the cost of your flight, compared to a flight in the morning.
Weekly flight availability from Idaho to Illinois
Explore weekly flight availability from Idaho 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 10, 2026.
The most flights from USID to USIL are scheduled on a Monday (9 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (9 on average).
How much does it cost to fly round-trip from Idaho to Illinois?
How far ahead should I book a flight from Idaho to Illinois?
Booking 90 days in advance of your planned departure date is, on average, the best time to get cheap flights from Idaho to Illinois. The general trend is that the closer you book to the departure date, the more expensive your flight will be.
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 10, 2026.
Read through reviews of airlines operating flights from Idaho to Illinois, such as Alaska Airlines,Southwest, andDelta. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Crew
8.5
Comfort
7.8
Boarding
8.1
Food
7.0
Entertainment
7.0
Overall
7.9
Reviews
1 / 20
4.0
OkayAnonymous,Jun 2026
SEA - RNO
Crew
8.5
Comfort
7.8
Boarding
8.1
Food
7.0
Entertainment
7.0
Overall
7.9
Reviews
1 / 20
4.0
OkayAnonymous,Jun 2026
SEA - RNO
Crew
8.5
Comfort
7.8
Boarding
8.1
Food
7.0
Entertainment
7.0
Overall
7.9
Reviews
1 / 20
4.0
OkayAnonymous,Jun 2026
SEA - RNO
Crew
8.5
Comfort
7.8
Boarding
8.1
Food
7.0
Entertainment
7.0
Overall
7.9
Reviews
1 / 20
4.0
OkayAnonymous,Jun 2026
SEA - RNO
Crew
8.5
Comfort
7.8
Boarding
8.1
Food
7.0
Entertainment
7.0
Overall
7.9
Reviews
1 / 20
4.0
OkayAnonymous,Jun 2026
SEA - RNO
Crew
8.5
Comfort
7.8
Boarding
8.1
Food
7.0
Entertainment
7.0
Overall
7.9
Reviews
1 / 20
4.0
OkayAnonymous,Jun 2026
SEA - RNO
Related info for your journey
Find useful and relevant information for your journey from Idaho 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 Idaho 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 Idaho to Illinois by cabin class
Find flights from Idaho to Illinois, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Idaho and Illinois flights
Browse other Idaho and Illinois flight options. Last updated on June 10, 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 Idaho after your stay in Illinois
Idaho to Illinois flights
Consider these flights traveling from Idaho to Illinois.
Top 5 airlines flying from Idaho to Illinois
Discover the top 5 airlines that operate flights from Idaho 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 10, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$144 | Average$419 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$234 | Average$395 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$243 | Average$465 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$269 | Average$402 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$298 | Average$390 | FlexibilityNo cancel fee | On-time75% |