$121+ Cheap flights from Illinois to Idaho
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.
ORD — BOI
Aug 24 — Aug 311
Round-trip
1 adult, Economy
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Find cheap flights from Illinois to Idaho with Cheapflights
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Cheapest flights from Illinois to IdahoExplore the most affordable flight options available from Illinois to Idaho. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 25, 2026.
Explore the most affordable flight options available from Illinois to Idaho. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 25, 2026.
This Kiwi.com deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” 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 8/128:08 pm
STL
- BOI
1 stop17h 21m
Frontier
Thu 8/2012:24 pm
BOI
- STL
1 stop5h 49m
Frontier
Deal found 7/22![Frontier logo]()
$221
This Priceline deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” 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.
Mon 9/286:50 am
ORD
- BOI
1 stop9h 07m
Frontier
Tue 9/2912:59 pm
BOI
- ORD
1 stop7h 36m
Frontier
Deal found 7/22![Frontier logo]()
$250
This Frontier deal was found by Cheapflights users on 7/20. Clicking the “Pick Dates” 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.
Mon 9/216:50 am
ORD
- BOI
1 stop9h 07m
Frontier
Mon 9/283:52 pm
BOI
- ORD
1 stop12h 50m
Frontier
Deal found 7/20![Frontier logo]()
$254
This CheapOair deal was found by Cheapflights users on 7/24. Clicking the “Pick Dates” 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 9/2311:06 am
ORD
- BOI
1 stop25h 58m
Frontier
Tue 10/2012:23 pm
BOI
- ORD
1 stop20h 38m
Frontier
Deal found 7/24![Frontier logo]()
$257
This Frontier deal was found by Cheapflights users on 7/21. Clicking the “Pick Dates” 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.
Mon 9/146:50 am
ORD
- BOI
1 stop9h 07m
Frontier
Fri 9/183:52 pm
BOI
- ORD
1 stop12h 50m
Frontier
Deal found 7/21![Frontier logo]()
$260
This Kiwi.com deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” 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 8/128:08 pm
STL
- BOI
1 stop17h 21m
Frontier
Tue 8/181:24 pm
BOI
- STL
2 stops50h 58m
Frontier
Deal found 7/22![Frontier logo]()
$263
This Kiwi.com deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” 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 10/711:06 am
ORD
- BOI
2 stops28h 51m
Frontier
Tue 10/1312:23 pm
BOI
- ORD
1 stop20h 38m
Frontier
Deal found 7/23![Frontier logo]()
$267
This Frontier deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” 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.
Mon 9/216:50 am
ORD
- BOI
1 stop9h 07m
Frontier
Sun 9/273:52 pm
BOI
- ORD
1 stop12h 50m
Frontier
Deal found 7/22![Frontier logo]()
$270
This CheapOair deal was found by Cheapflights users on 7/24. Clicking the “Pick Dates” 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 9/1611:06 am
ORD
- BOI
1 stop25h 58m
Frontier
Fri 9/183:52 pm
BOI
- ORD
1 stop12h 50m
Frontier
Deal found 7/24![Frontier logo]()
$272
This CheapOair deal was found by Cheapflights users on 7/24. Clicking the “Pick Dates” 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 9/911:06 am
ORD
- BOI
1 stop25h 58m
Frontier
Mon 9/143:52 pm
BOI
- ORD
1 stop12h 50m
Frontier
Deal found 7/24![Frontier logo]()
$275
This Frontier deal was found by Cheapflights users on 7/21. Clicking the “Pick Dates” 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 9/116:50 am
ORD
- BOI
1 stop9h 07m
Frontier
Sun 9/133:52 pm
BOI
- ORD
1 stop12h 50m
Frontier
Deal found 7/21![Frontier logo]()
$276
This Kiwi.com deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” 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 8/158:08 pm
STL
- BOI
1 stop17h 21m
Frontier
Thu 8/2012:24 pm
BOI
- STL
1 stop5h 49m
Frontier
Deal found 7/22![Frontier logo]()
$280
Best flights from Illinois to IdahoDiscover carefully curated flight deals from Illinois to Idaho that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated July 25, 2026.
Discover carefully curated flight deals from Illinois to Idaho that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated July 25, 2026.
This Southwest deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/248:50 pm
MDW
- GEG
Nonstop3h 55m
Southwest
Mon 9/286:00 am
GEG
- MDW
Nonstop3h 30m
Southwest
Deal found 7/23![Southwest logo]()
$297
This United Airlines deal was found by Cheapflights users on 7/21. Clicking the “Pick Dates” 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 9/125:00 am
ORD
- IDA
1 stop5h 53m
United Airlines
Sat 9/195:53 pm
IDA
- ORD
1 stop5h 06m
United Airlines
Deal found 7/21![United Airlines logo]()
$301
This Alaska Airlines deal was found by Cheapflights users on 7/21. Clicking the “Pick Dates” 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 11/246:07 am
ORD
- BOI
1 stop7h 16m
Alaska Airlines
Tue 12/11:00 pm
BOI
- ORD
1 stop9h 59m
Alaska Airlines
Deal found 7/21![Alaska Airlines logo]()
$315
This Delta deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” 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 9/152:05 pm
ORD
- IDA
1 stop5h 12m
Delta
Sun 9/206:00 am
IDA
- ORD
1 stop4h 55m
Delta
Deal found 7/23![Delta logo]()
$320
This American Airlines deal was found by Cheapflights users on 7/20. Clicking the “Pick Dates” 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 9/145:43 am
STL
- JAC
1 stop5h 36m
American Airlines
Thu 9/174:30 pm
JAC
- STL
1 stop6h 13m
American Airlines
Deal found 7/20![American Airlines logo]()
$419
This Southwest deal was found by Cheapflights users on 7/21. Clicking the “Pick Dates” 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 8/208:50 pm
MDW
- GEG
Nonstop3h 50m
Southwest
Sat 8/221:40 pm
GEG
- MDW
1 stop6h 35m
Southwest
Deal found 7/21![Southwest logo]()
$307
This Alaska Airlines deal was found by Cheapflights users on 7/20. Clicking the “Pick Dates” 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 11/173:59 pm
ORD
- BOI
1 stop7h 21m
Alaska Airlines
Wed 11/184:21 pm
BOI
- ORD
1 stop6h 36m
Alaska Airlines
Deal found 7/20![Alaska Airlines logo]()
$315
This United Airlines deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” 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 8/195:00 am
ORD
- IDA
1 stop5h 51m
United Airlines
Wed 8/264:04 pm
IDA
- ORD
1 stop6h 55m
United Airlines
Deal found 7/22![United Airlines logo]()
$320
This Delta deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” 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 8/192:00 pm
ORD
- IDA
1 stop5h 20m
Delta
Wed 8/263:17 pm
IDA
- ORD
1 stop5h 16m
Delta
Deal found 7/22![Delta logo]()
$320
This Alaska Airlines deal was found by Cheapflights users on 7/21. Clicking the “Pick Dates” 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 1/195:55 pm
ORD
- BOI
1 stop7h 16m
Alaska Airlines
Sat 1/239:53 am
BOI
- ORD
1 stop9h 02m
Alaska Airlines
Deal found 7/21![Alaska Airlines logo]()
$315
This Southwest deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/1311:40 am
MDW
- BOI
Nonstop3h 30m
Southwest
Thu 8/202:55 pm
BOI
- MDW
1 stop7h 50m
Southwest
Deal found 7/23![Southwest logo]()
$317
This Delta deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” 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 1/195:35 pm
MDW
- BOI
1 stop7h 20m
Delta
Sat 1/231:43 pm
BOI
- MDW
1 stop7h 27m
Delta
Deal found 7/23![Delta logo]()
$327
This United Airlines deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” 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 11/58:40 am
ORD
- BOI
Nonstop4h 01m
United Airlines
Mon 11/912:32 pm
BOI
- ORD
Nonstop3h 24m
United Airlines
Deal found 7/22![United Airlines logo]()
$332
This Alaska Airlines deal was found by Cheapflights users on 7/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/196:00 am
ORD
- BOI
1 stop7h 36m
Alaska Airlines
Tue 8/257:20 am
BOI
- ORD
1 stop11h 01m
Alaska Airlines
Deal found 7/20![Alaska Airlines logo]()
$315
This Southwest deal was found by Cheapflights users on 7/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/1710:20 am
MDW
- BOI
1 stop6h 55m
Southwest
Thu 8/2012:10 pm
BOI
- MDW
Nonstop3h 20m
Southwest
Deal found 7/20![Southwest logo]()
$317
This Delta deal was found by Cheapflights users on 7/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/245:57 pm
ORD
- GEG
1 stop7h 12m
Delta
Mon 8/311:00 pm
GEG
- ORD
1 stop8h 29m
Delta
Deal found 7/24![Delta logo]()
$327
This Southwest deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” 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 10/196:05 am
MDW
- GEG
1 stop5h 55m
Southwest
Tue 10/271:55 pm
GEG
- MDW
1 stop7h 15m
Southwest
Deal found 7/22![Southwest logo]()
$317
This Delta deal was found by Cheapflights users on 7/20. Clicking the “Pick Dates” 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 10/237:35 am
ORD
- IDA
1 stop5h 47m
Delta
Mon 10/266:00 am
IDA
- ORD
1 stop4h 55m
Delta
Deal found 7/20![Delta logo]()
$329
This Alaska Airlines deal was found by Cheapflights users on 7/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/86:00 am
ORD
- GEG
1 stop8h 39m
Alaska Airlines
Tue 9/151:36 pm
GEG
- ORD
1 stop8h 23m
Alaska Airlines
Deal found 7/24![Alaska Airlines logo]()
$334
This Southwest deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” 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 9/84:45 pm
MDW
- BOI
1 stop6h 40m
Southwest
Fri 9/1112:10 pm
BOI
- MDW
Nonstop3h 20m
Southwest
Deal found 7/22![Southwest logo]()
$322
This Delta deal was found by Cheapflights users on 7/24. Clicking the “Pick Dates” 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 9/87:00 am
ORD
- GEG
1 stop7h 20m
Delta
Tue 9/155:10 am
GEG
- ORD
2 stops10h 54m
Delta
Deal found 7/24![Delta logo]()
$332
This Alaska Airlines deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/136:00 am
ORD
- GEG
1 stop8h 39m
Alaska Airlines
Sat 9/1912:17 pm
GEG
- ORD
1 stop9h 42m
Alaska Airlines
Deal found 7/22![Alaska Airlines logo]()
$338
This United Airlines deal was found by Cheapflights users on 7/20. Clicking the “Pick Dates” 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 9/148:00 am
STL
- JAC
2 stops8h 28m
United Airlines
Thu 9/177:00 am
JAC
- STL
1 stop4h 40m
United Airlines
Deal found 7/20![United Airlines logo]()
$435
This Southwest deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” 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 9/84:45 pm
MDW
- BOI
1 stop6h 40m
Southwest
Thu 9/106:30 am
BOI
- MDW
1 stop9h 30m
Southwest
Deal found 7/22![Southwest logo]()
$327
This Delta deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/2412:50 pm
ORD
- GEG
1 stop6h 19m
Delta
Mon 9/2810:50 pm
GEG
- ORD
2 stops9h 47m
Delta
Deal found 7/22![Delta logo]()
$332
This Alaska Airlines deal was found by Cheapflights users on 7/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/186:00 am
ORD
- BOI
1 stop7h 35m
Alaska Airlines
Sat 10/317:20 am
BOI
- ORD
1 stop10h 33m
Alaska Airlines
Deal found 7/20![Alaska Airlines logo]()
$345
This Delta deal was found by Cheapflights users on 7/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/41:59 pm
ORD
- IDA
2 stops9h 33m
Delta
Mon 9/76:00 am
IDA
- ORD
1 stop4h 59m
Delta
Deal found 7/19![Delta logo]()
$334
This Southwest deal was found by Cheapflights users on 7/20. Clicking the “Pick Dates” 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 8/193:50 pm
MDW
- GEG
1 stop8h 35m
Southwest
Tue 8/256:15 am
GEG
- MDW
1 stop6h 50m
Southwest
Deal found 7/20![Southwest logo]()
$341
This United Airlines deal was found by Cheapflights users on 7/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/94:30 pm
ORD
- JAC
Nonstop3h 21m
United Airlines
Tue 10/64:28 pm
JAC
- ORD
1 stop6h 31m
United Airlines
Deal found 7/21![United Airlines logo]()
$455
This Alaska Airlines deal was found by Cheapflights users on 7/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/67:36 pm
STL
- BOI
1 stop15h 16m
Alaska Airlines
Mon 9/288:25 pm
BOI
- STL
1 stop19h 45m
Alaska Airlines
Deal found 7/24![Alaska Airlines logo]()
$368
Last-minute flights from Illinois to IdahoDiscover last-minute flight deals from Illinois to Idaho. Data last updated July 25, 2026 and is based on user searches.
Discover last-minute flight deals from Illinois to Idaho. Data last updated July 25, 2026 and is based on user searches.
This Kiwi.com deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” 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 8/108:08 pm
STL
- BOI
1 stop17h 21m
Frontier
Thu 8/2012:24 pm
BOI
- STL
1 stop5h 49m
Frontier
Deal found 7/22![Frontier logo]()
$281
This Kiwi.com deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” 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 8/128:08 pm
STL
- BOI
1 stop17h 21m
Frontier
Thu 8/2012:24 pm
BOI
- STL
1 stop5h 49m
Frontier
Deal found 7/22![Frontier logo]()
$221
This Kiwi.com deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” 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 8/128:08 pm
STL
- BOI
1 stop17h 21m
Frontier
Tue 8/181:24 pm
BOI
- STL
2 stops50h 58m
Frontier
Deal found 7/22![Frontier logo]()
$263
This Southwest deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/1311:40 am
MDW
- BOI
Nonstop3h 30m
Southwest
Thu 8/2012:10 pm
BOI
- MDW
Nonstop3h 20m
Southwest
Deal found 7/23![Southwest logo]()
$307
This Kiwi.com deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” 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 8/158:08 pm
STL
- BOI
1 stop17h 21m
Frontier
Thu 8/2012:24 pm
BOI
- STL
1 stop5h 49m
Frontier
Deal found 7/22![Frontier logo]()
$280
This American Airlines deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/1511:30 am
ORD
- GEG
Nonstop4h 07m
American Airlines
Thu 8/202:27 pm
GEG
- ORD
Nonstop4h 01m
American Airlines
Deal found 7/22![American Airlines logo]()
$297
This Expedia deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” 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.
Sat 8/156:00 am
ORD
- BOI
1 stop7h 47m
Alaska Airlines
Sat 8/227:20 am
BOI
- ORD
1 stop11h 01m
Alaska Airlines
Deal found 7/23![Alaska Airlines logo]()
$306
This Southwest deal was found by Cheapflights users on 7/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/178:50 pm
MDW
- GEG
Nonstop3h 50m
Southwest
Mon 8/246:00 am
GEG
- MDW
Nonstop3h 30m
Southwest
Deal found 7/20![Southwest logo]()
$297
This Alaska Airlines deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” 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 8/226:00 am
ORD
- GEG
1 stop7h 03m
Alaska Airlines
Sat 8/297:03 am
GEG
- ORD
1 stop10h 18m
Alaska Airlines
Deal found 7/22![Alaska Airlines logo]()
$301
This Vliegwinkel deal was found by Cheapflights users on 7/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Vliegwinkel is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/242:18 pm
ORD
- GEG
1 stop10h 31m
Alaska Airlines
Mon 8/317:03 am
GEG
- ORD
1 stop10h 18m
Alaska Airlines
Deal found 7/24![Alaska Airlines logo]()
$296
This American Airlines deal was found by Cheapflights users on 7/24. Clicking the “Pick Dates” 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 8/2411:30 am
ORD
- GEG
Nonstop4h 07m
American Airlines
Mon 8/312:27 pm
GEG
- ORD
Nonstop4h 01m
American Airlines
Deal found 7/24![American Airlines logo]()
$298
This Expedia deal was found by Cheapflights users on 7/20. Clicking the “Pick Dates” 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.
Sat 8/296:00 am
ORD
- BOI
1 stop7h 36m
Alaska Airlines
Sat 9/52:17 pm
BOI
- ORD
1 stop8h 42m
Alaska Airlines
Deal found 7/20![Alaska Airlines logo]()
$301
One-way flights from Illinois to IdahoSearch for one-way flight options from Illinois to Idaho. Find affordable one-way fares based on user searches. Data last updated July 25, 2026.
Search for one-way flight options from Illinois to Idaho. Find affordable one-way fares based on user searches. Data last updated July 25, 2026.
This Kiwi.com deal was found by Cheapflights users on 7/21. Clicking the “Pick Dates” 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 8/129:57 pm
ORD
- BOI
1 stop15h 32m
Frontier
Deal found 7/21![Frontier logo]()
$121
This Kiwi.com deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” 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 9/2110:40 pm
ORD
- BOI
1 stop14h 24m
Frontier
Deal found 7/22![Frontier logo]()
$123
This Kiwi.com deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” 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 9/2310:40 pm
ORD
- BOI
1 stop14h 24m
Frontier
Deal found 7/22![Frontier logo]()
$124
This Kiwi.com deal was found by Cheapflights users on 7/24. Clicking the “Pick Dates” 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 8/262:41 pm
ORD
- BOI
1 stop21h 48m
Frontier
Deal found 7/24![Frontier logo]()
$125
This Kiwi.com deal was found by Cheapflights users on 7/24. Clicking the “Pick Dates” 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 8/242:41 pm
ORD
- BOI
1 stop22h 48m
Frontier
Deal found 7/24![Frontier logo]()
$126
This Expedia deal was found by Cheapflights users on 7/20. Clicking the “Pick Dates” 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 10/1911:06 am
ORD
- BOI
1 stop25h 22m
Frontier
Deal found 7/20![Frontier logo]()
$133
This CheapOair deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” 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 8/222:41 pm
ORD
- BOI
1 stop21h 48m
Frontier
Deal found 7/23![Frontier logo]()
$135
This Priceline deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” 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 9/206:50 am
ORD
- BOI
1 stop9h 07m
Frontier
Deal found 7/22![Frontier logo]()
$138
This Trip.com deal was found by Cheapflights users on 7/21. Clicking the “Pick Dates” 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.
Sat 8/159:57 pm
ORD
- BOI
1 stop15h 32m
Frontier
Deal found 7/21![Frontier logo]()
$140
This Priceline deal was found by Cheapflights users on 7/24. Clicking the “Pick Dates” 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.
Sat 9/56:00 am
ORD
- GEG
1 stop8h 31m
Alaska Airlines
Deal found 7/24![Alaska Airlines logo]()
$144
This Southwest deal was found by Cheapflights users on 7/21. Clicking the “Pick Dates” 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 8/208:50 pm
MDW
- GEG
Nonstop3h 50m
Southwest
Deal found 7/21![Southwest logo]()
$149
This American Airlines deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/111:30 am
ORD
- GEG
Nonstop4h 07m
American Airlines
Deal found 7/22![American Airlines logo]()
$149
Find flight deals from Illinois to Idaho
Keep the following information in mind while searching for Illinois to Idaho flight deals. Data was last updated July 25, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $221 (Kiwi.com) |
One-way from | $121 (Kiwi.com) |
Popular in | June |
Cheapest in | February |
Average price | $387 |
Good round-trip deal | $346 or less |
Good one-way deal | $225 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Illinois to Idaho 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 July 25, 2026.
Use the filters below to find and compare flights from Illinois to Idaho that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
Quickest round-trip
ChicagoSpokane
MDW - GEG
MDWGEG
Chicago Midway
Thu 9/24
8:50 pm-10:45 pm
Nonstop3h 55m
Spokane
Mon 9/28
6:00 am-11:30 am
Nonstop3h 30m
$297
ChicagoIdaho Falls
ORD - IDA
ORDIDA
Chicago O'Hare Intl
Sat 9/12
5:00 am-9:53 am
1 stop5h 53m
Idaho Falls Fanning Field
Sat 9/19
5:53 pm-11:59 pm
1 stop5h 06m
$301
ChicagoSpokane
MDW - GEG
MDWGEG
Chicago Midway
Thu 8/20
8:50 pm-10:40 pm
Nonstop3h 50m
Spokane
Sat 8/22
1:40 pm-10:15 pm
1 stop6h 35m
$307
ChicagoBoise
ORD - BOI
ORDBOI
Chicago O'Hare Intl
Tue 11/24
6:07 am-12:23 pm
1 stop7h 16m
Boise Air Term. Gowen Fld
Tue 12/1
1:00 pm-11:59 pm
1 stop9h 59m
$315
ChicagoBoise
ORD - BOI
ORDBOI
Chicago O'Hare Intl
Tue 11/17
3:59 pm-10:20 pm
1 stop7h 21m
Boise Air Term. Gowen Fld
Wed 11/18
4:21 pm-11:57 pm
1 stop6h 36m
$315
ChicagoBoise
ORD - BOI
ORDBOI
Chicago O'Hare Intl
Tue 1/19
5:55 pm-12:11 am
1 stop7h 16m
Boise Air Term. Gowen Fld
Sat 1/23
9:53 am-7:55 pm
1 stop9h 02m
$315
ChicagoBoise
ORD - BOI
ORDBOI
Chicago O'Hare Intl
Wed 8/19
6:00 am-12:36 pm
1 stop7h 36m
Boise Air Term. Gowen Fld
Tue 8/25
7:20 am-7:21 pm
1 stop11h 01m
$315
ChicagoBoise
MDW - BOI
MDWBOI
Chicago Midway
Thu 8/13
11:40 am-2:10 pm
Nonstop3h 30m
Boise Air Term. Gowen Fld
Thu 8/20
2:55 pm-11:45 pm
1 stop7h 50m
$317
ChicagoBoise
MDW - BOI
MDWBOI
Chicago Midway
Mon 8/17
10:20 am-4:15 pm
1 stop6h 55m
Boise Air Term. Gowen Fld
Thu 8/20
12:10 pm-4:30 pm
Nonstop3h 20m
$317
ChicagoSpokane
MDW - GEG
MDWGEG
Chicago Midway
Mon 10/19
6:05 am-10:00 am
1 stop5h 55m
Spokane
Tue 10/27
1:55 pm-11:10 pm
1 stop7h 15m
$317
Showing 1-10 of 60 resultsSorted by cheapest first
Best time to book a flight from Illinois to Idaho
Have a flexible travel schedule? Discover the best time to fly to Idaho from Illinois with our price prediction graph.
MDW-GEG
ORD-IDA
ORD-BOI
STL-JAC
MDW-BOI
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 Illinois to Idaho
USIL-USID
MDW-GEG
ORD-IDA
ORD-BOI
STL-JAC
What is the cheapest month to book a flight from Illinois to Idaho?
Currently, February is the cheapest month in which you can book a flight from Illinois to Idaho (average of $323). Flying from Illinois to Idaho in December is currently the most expensive (average of $545). 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 IL to ID?
Find hourly flight availability from Illinois to Idaho. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated July 25, 2026.
It’s typically best to fly out from Illinois to Idaho at noon. Doing so could potentially save you 29% on the flight price compared to flying in the afternoon, which is usually more expensive.
Weekly flight availability from Illinois to Idaho
Explore weekly flight availability from Illinois to Idaho. 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 July 25, 2026.
The most flights from USIL to USID are scheduled on a Monday (7 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (6 on average).
How much does it cost to fly round-trip from Illinois to Idaho?
Airfare is below average for this route at the moment.
Illinois to Idaho flights typically cost between $328 and $442 in September.The cheapest round-trip price found within the last 5 days was $250 on Frontier (Sep 28-Sep 29).
How far ahead should I book a flight from Illinois to Idaho?
The best time to book flights from Illinois to Idaho is 74 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.
Reviews of airlines servicing Idaho
Get insights into the airlines that provide service to Idaho. 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 Idaho. Reviews last updated July 25, 2026.
Read reviews from past customers who have flown Southwest,Alaska Airlines, andDelta from Illinois to Idaho. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Food
7.0
Boarding
8.1
Overall
8.0
Comfort
8.0
Crew
8.6
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Food
7.0
Boarding
8.1
Overall
8.0
Comfort
8.0
Crew
8.6
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Food
7.0
Boarding
8.1
Overall
8.0
Comfort
8.0
Crew
8.6
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Food
7.0
Boarding
8.1
Overall
8.0
Comfort
8.0
Crew
8.6
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Food
7.0
Boarding
8.1
Overall
8.0
Comfort
8.0
Crew
8.6
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Food
7.0
Boarding
8.1
Overall
8.0
Comfort
8.0
Crew
8.6
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Related info for your journey
Find useful and relevant information for your journey from Illinois to Idaho. 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 Illinois to Idaho
See prices for flight routes from nearby airports that may be better suited for you.
Complete your trip
Complete your trip to Idaho by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Illinois to Idaho by cabin class
Find flights from Illinois to Idaho, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Illinois and Idaho flights
Browse other Illinois and Idaho flight options. Last updated on July 25, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Find a return flight route from Idaho
Find the right flight back to Illinois after your stay in Idaho
Illinois to Idaho flights
Consider these flights traveling from Illinois to Idaho.
Top 5 airlines flying from Illinois to Idaho
Discover the top 5 airlines that operate flights from Illinois to Idaho. 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 July 25, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$263 | Average$510 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$268 | Average$470 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$268 | Average$403 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$288 | Average$458 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$348 | Average$364 | FlexibilityNo cancel fee | On-time75% |