$114+ 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 4/14. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — BOI
Apr 16 — Apr 231
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 March 17, 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 March 17, 2026.
This Frontier deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/48:16 pm
STL
- BOI
1 stop15h 52m
Frontier
Sun 4/1212:03 pm
BOI
- STL
1 stop20h 45m
Frontier
Deal found 3/12![Frontier logo]()
$240
This Trip.com deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/186:00 am
ORD
- BOI
1 stop7h 22m
Multiple Airlines
Sat 4/252:57 pm
BOI
- ORD
1 stop8h 02m
Multiple Airlines
Deal found 3/15![Multiple Airlines logo]()
$260
This CheapOair deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/83:29 pm
ORD
- BOI
1 stop20h 39m
Frontier
Sun 4/1212:03 pm
BOI
- ORD
1 stop24h 16m
Frontier
Deal found 3/15![Frontier logo]()
$261
This Expedia deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/306:00 am
ORD
- GEG
1 stop6h 38m
Multiple Airlines
Wed 5/612:33 pm
GEG
- ORD
1 stop6h 04m
Multiple Airlines
Deal found 3/12![Multiple Airlines logo]()
$271
This Alaska Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/158:20 am
ORD
- BOI
1 stop16h 27m
Alaska Airlines
Sat 4/182:22 pm
BOI
- ORD
1 stop8h 37m
Alaska Airlines
Deal found 3/12![Alaska Airlines logo]()
$273
This Expedia deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/88:48 pm
ORD
- BOI
1 stop13h 54m
Multiple Airlines
Tue 5/121:22 pm
BOI
- ORD
1 stop6h 15m
Multiple Airlines
Deal found 3/15![Multiple Airlines logo]()
$275
This Expedia deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/184:10 pm
ORD
- GEG
1 stop9h 49m
Alaska Airlines
Sat 4/255:05 am
GEG
- ORD
1 stop7h 03m
Alaska Airlines
Deal found 3/12![Alaska Airlines logo]()
$275
This Alaska Airlines deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/226:00 am
ORD
- BOI
1 stop7h 35m
Alaska Airlines
Tue 4/286:00 am
BOI
- ORD
1 stop9h 56m
Alaska Airlines
Deal found 3/16![Alaska Airlines logo]()
$277
This Alaska Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/73:50 pm
STL
- BOI
1 stop8h 07m
Alaska Airlines
Wed 4/82:22 pm
BOI
- STL
1 stop8h 37m
Alaska Airlines
Deal found 3/12![Alaska Airlines logo]()
$277
This Alaska Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/285:52 pm
ORD
- GEG
1 stop7h 19m
Alaska Airlines
Sat 5/22:45 pm
GEG
- ORD
1 stop7h 14m
Alaska Airlines
Deal found 3/12![Alaska Airlines logo]()
$277
This Expedia deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/154:10 pm
ORD
- BOI
1 stop8h 37m
Alaska Airlines
Wed 4/226:00 am
BOI
- ORD
1 stop9h 56m
Alaska Airlines
Deal found 3/16![Alaska Airlines logo]()
$280
This CheapOair deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/239:42 pm
ORD
- BOI
1 stop15h 48m
Frontier
Tue 5/261:25 pm
BOI
- ORD
1 stop6h 12m
Frontier
Deal found 3/15![Frontier logo]()
$281
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 March 17, 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 March 17, 2026.
This Alaska Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/73:50 pm
STL
- BOI
1 stop8h 07m
Alaska Airlines
Wed 4/82:22 pm
BOI
- STL
1 stop8h 37m
Alaska Airlines
Deal found 3/12![Alaska Airlines logo]()
$277
This Delta deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/76:12 pm
STL
- BOI
1 stop4h 59m
Delta
Sat 4/118:00 am
BOI
- STL
1 stop5h 43m
Delta
Deal found 3/12![Delta logo]()
$297
This Southwest deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/296:25 pm
MDW
- BOI
1 stop7h 20m
Southwest
Fri 6/58:45 am
BOI
- MDW
Nonstop3h 20m
Southwest
Deal found 3/12![Southwest logo]()
$299
This United Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/244:35 pm
ORD
- GEG
Nonstop4h 16m
United Airlines
Sun 4/261:46 pm
GEG
- ORD
1 stop7h 42m
United Airlines
Deal found 3/12![United Airlines logo]()
$319
This Alaska Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/285:52 pm
ORD
- GEG
1 stop7h 19m
Alaska Airlines
Sat 5/22:45 pm
GEG
- ORD
1 stop7h 14m
Alaska Airlines
Deal found 3/12![Alaska Airlines logo]()
$277
This Delta deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/156:20 pm
ORD
- BOI
1 stop6h 35m
Delta
Mon 5/2511:39 pm
BOI
- ORD
1 stop9h 37m
Delta
Deal found 3/12![Delta logo]()
$309
This Alaska Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/104:10 pm
ORD
- BOI
1 stop8h 37m
Alaska Airlines
Tue 4/142:22 pm
BOI
- ORD
1 stop8h 37m
Alaska Airlines
Deal found 3/12![Alaska Airlines logo]()
$283
This Southwest deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/105:15 pm
MDW
- BOI
2 stops8h 45m
Southwest
Mon 4/134:20 pm
BOI
- MDW
1 stop6h 20m
Southwest
Deal found 3/12![Southwest logo]()
$314
This Delta deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/97:25 am
ORD
- BOI
1 stop9h 38m
Delta
Thu 4/168:30 am
BOI
- ORD
2 stops11h 55m
Delta
Deal found 3/12![Delta logo]()
$314
This United Airlines deal was found by Cheapflights users on 3/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/184:30 pm
ORD
- JAC
Nonstop3h 22m
United Airlines
Fri 8/212:30 pm
JAC
- ORD
1 stop7h 11m
United Airlines
Deal found 3/14![United Airlines logo]()
$349
This Southwest deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/277:30 am
MDW
- GEG
1 stop8h 15m
Southwest
Sun 6/76:40 pm
GEG
- MDW
1 stop8h 30m
Southwest
Deal found 3/12![Southwest logo]()
$323
This Delta deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/235:41 pm
ORD
- BOI
1 stop7h 05m
Delta
Mon 5/2511:39 pm
BOI
- ORD
2 stops9h 48m
Delta
Deal found 3/12![Delta logo]()
$314
This United Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/175:00 am
ORD
- JAC
1 stop5h 33m
United Airlines
Fri 8/281:45 pm
JAC
- ORD
1 stop6h 27m
United Airlines
Deal found 3/12![United Airlines logo]()
$357
This Southwest deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/157:30 am
MDW
- BOI
2 stops10h 10m
Southwest
Sat 4/183:25 pm
BOI
- MDW
2 stops12h 10m
Southwest
Deal found 3/12![Southwest logo]()
$325
This Alaska Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/103:09 pm
ORD
- IDA
1 stop8h 30m
Alaska Airlines
Sat 9/194:00 pm
IDA
- ORD
1 stop6h 41m
Alaska Airlines
Deal found 3/12![Alaska Airlines logo]()
$330
This United Airlines deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/25:00 am
ORD
- JAC
1 stop5h 46m
United Airlines
Fri 6/54:23 pm
JAC
- ORD
1 stop7h 21m
United Airlines
Deal found 3/16![United Airlines logo]()
$359
This Southwest deal was found by Cheapflights users on 3/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 4/195:10 am
MDW
- GEG
1 stop7h 25m
Southwest
Mon 4/202:50 pm
GEG
- MDW
1 stop6h 50m
Southwest
Deal found 3/13![Southwest logo]()
$329
This Delta deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/112:05 pm
MDW
- BOI
1 stop8h 04m
Delta
Tue 4/148:30 am
BOI
- MDW
2 stops9h 06m
Delta
Deal found 3/12![Delta logo]()
$334
This Alaska Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 6/206:22 am
ORD
- JAC
1 stop9h 45m
Alaska Airlines
Wed 6/242:11 pm
JAC
- ORD
1 stop8h 28m
Alaska Airlines
Deal found 3/12![Alaska Airlines logo]()
$344
This Southwest deal was found by Cheapflights users on 3/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/255:30 pm
MDW
- GEG
1 stop5h 45m
Southwest
Wed 4/295:10 am
GEG
- MDW
1 stop7h 00m
Southwest
Deal found 3/14![Southwest logo]()
$329
This United Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/78:54 am
STL
- BOI
2 stops12h 19m
United Airlines
Wed 4/85:00 am
BOI
- STL
1 stop7h 08m
United Airlines
Deal found 3/12![United Airlines logo]()
$362
This Delta deal was found by Cheapflights users on 3/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/146:20 pm
ORD
- BOI
1 stop6h 35m
Delta
Mon 5/183:14 pm
BOI
- ORD
1 stop7h 43m
Delta
Deal found 3/14![Delta logo]()
$345
This Alaska Airlines deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 4/127:59 pm
ORD
- BOI
1 stop28h 48m
Alaska Airlines
Tue 4/218:28 pm
BOI
- ORD
1 stop9h 12m
Alaska Airlines
Deal found 3/16![Alaska Airlines logo]()
$350
This Southwest deal was found by Cheapflights users on 3/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/68:15 pm
MDW
- GEG
1 stop7h 10m
Southwest
Thu 4/91:30 pm
GEG
- MDW
1 stop8h 25m
Southwest
Deal found 3/11![Southwest logo]()
$329
This United Airlines deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/115:00 am
ORD
- IDA
1 stop5h 50m
United Airlines
Sat 7/185:54 pm
IDA
- ORD
1 stop5h 50m
United Airlines
Deal found 3/15![United Airlines logo]()
$374
This Delta deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/92:20 pm
ORD
- BOI
1 stop8h 44m
Delta
Mon 4/138:40 pm
BOI
- ORD
2 stops10h 21m
Delta
Deal found 3/12![Delta logo]()
$351
This Alaska Airlines deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/292:20 pm
ORD
- GEG
1 stop10h 50m
Alaska Airlines
Sat 8/88:12 am
GEG
- ORD
1 stop8h 48m
Alaska Airlines
Deal found 3/16![Alaska Airlines logo]()
$355
This Southwest deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/182:05 pm
ORD
- GEG
2 stops9h 10m
Southwest
Sat 4/256:45 am
GEG
- ORD
2 stops13h 35m
Southwest
Deal found 3/12![Southwest logo]()
$339
This Delta deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/167:13 pm
MDW
- BOI
1 stop5h 33m
Delta
Tue 5/2611:39 pm
BOI
- MDW
1 stop9h 21m
Delta
Deal found 3/16![Delta logo]()
$355
This United Airlines deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 3/288:55 am
ORD
- JAC
Nonstop3h 29m
United Airlines
Wed 4/112:20 pm
JAC
- ORD
Nonstop3h 11m
United Airlines
Deal found 3/16![United Airlines logo]()
$399
Last-minute flights from Illinois to IdahoDiscover last-minute flight deals from Illinois to Idaho. Data last updated March 17, 2026 and is based on user searches.
Discover last-minute flight deals from Illinois to Idaho. Data last updated March 17, 2026 and is based on user searches.
This Frontier deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/48:16 pm
STL
- BOI
1 stop15h 52m
Frontier
Sun 4/1212:03 pm
BOI
- STL
1 stop20h 45m
Frontier
Deal found 3/12![Frontier logo]()
$240
This Alaska Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/73:50 pm
STL
- BOI
1 stop8h 07m
Alaska Airlines
Wed 4/82:22 pm
BOI
- STL
1 stop8h 37m
Alaska Airlines
Deal found 3/12![Alaska Airlines logo]()
$277
This CheapOair deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/83:29 pm
ORD
- BOI
1 stop20h 39m
Frontier
Sun 4/1212:03 pm
BOI
- ORD
1 stop24h 16m
Frontier
Deal found 3/15![Frontier logo]()
$261
This Booking.com deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/83:29 pm
ORD
- GEG
1 stop20h 52m
Frontier
Sun 4/1211:06 am
GEG
- ORD
1 stop24h 13m
Frontier
Deal found 3/15![Frontier logo]()
$283
This Alaska Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/104:10 pm
ORD
- BOI
1 stop8h 37m
Alaska Airlines
Tue 4/142:22 pm
BOI
- ORD
1 stop8h 37m
Alaska Airlines
Deal found 3/12![Alaska Airlines logo]()
$283
This Alaska Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/158:20 am
ORD
- BOI
1 stop16h 27m
Alaska Airlines
Sat 4/182:22 pm
BOI
- ORD
1 stop8h 37m
Alaska Airlines
Deal found 3/12![Alaska Airlines logo]()
$273
This Expedia deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/154:10 pm
ORD
- BOI
1 stop8h 37m
Alaska Airlines
Wed 4/226:00 am
BOI
- ORD
1 stop9h 56m
Alaska Airlines
Deal found 3/16![Alaska Airlines logo]()
$280
This Trip.com deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/186:00 am
ORD
- BOI
1 stop7h 22m
Multiple Airlines
Sat 4/252:57 pm
BOI
- ORD
1 stop8h 02m
Multiple Airlines
Deal found 3/15![Multiple Airlines logo]()
$260
This Expedia deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/184:10 pm
ORD
- GEG
1 stop9h 49m
Alaska Airlines
Sat 4/255:05 am
GEG
- ORD
1 stop7h 03m
Alaska Airlines
Deal found 3/12![Alaska Airlines logo]()
$275
This Alaska Airlines deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/226:00 am
ORD
- BOI
1 stop7h 35m
Alaska Airlines
Tue 4/286:00 am
BOI
- ORD
1 stop9h 56m
Alaska Airlines
Deal found 3/16![Alaska Airlines logo]()
$277
This Alaska Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/285:52 pm
ORD
- GEG
1 stop7h 19m
Alaska Airlines
Sat 5/22:45 pm
GEG
- ORD
1 stop7h 14m
Alaska Airlines
Deal found 3/12![Alaska Airlines logo]()
$277
This Expedia deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/306:00 am
ORD
- GEG
1 stop6h 38m
Multiple Airlines
Wed 5/612:33 pm
GEG
- ORD
1 stop6h 04m
Multiple Airlines
Deal found 3/12![Multiple Airlines logo]()
$271
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 March 17, 2026.
Search for one-way flight options from Illinois to Idaho. Find affordable one-way fares based on user searches. Data last updated March 17, 2026.
This Kiwi.com deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/143:27 pm
ORD
- BOI
2 stops44h 41m
Frontier
Deal found 3/12![Frontier logo]()
$114
This Gotogate deal was found by Cheapflights users on 3/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/83:29 pm
ORD
- BOI
1 stop20h 39m
Frontier
Deal found 3/14![Frontier logo]()
$115
This Booking.com deal was found by Cheapflights users on 3/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/115:53 pm
ORD
- BOI
1 stop18h 15m
Frontier
Deal found 3/14![Frontier logo]()
$116
This Kiwi.com deal was found by Cheapflights users on 3/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/139:42 pm
ORD
- BOI
1 stop15h 45m
Frontier
Deal found 3/13![Frontier logo]()
$122
This Kiwi.com deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/153:27 pm
ORD
- BOI
2 stops20h 41m
Frontier
Deal found 3/12![Frontier logo]()
$127
This Kiwi.com deal was found by Cheapflights users on 3/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/152:15 pm
MDW
- BOI
2 stops21h 53m
Frontier
Deal found 3/13![Frontier logo]()
$128
This Trip.com deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/156:39 pm
ORD
- GEG
1 stop7h 20m
Alaska Airlines
Deal found 3/12![Alaska Airlines logo]()
$133
This Alaska Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/104:10 pm
ORD
- BOI
1 stop8h 37m
Alaska Airlines
Deal found 3/12![Alaska Airlines logo]()
$135
This Mytrip deal was found by Cheapflights users on 3/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/83:29 pm
ORD
- GEG
1 stop20h 52m
Frontier
Deal found 3/14![Frontier logo]()
$135
This Alaska Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/93:52 pm
ORD
- GEG
1 stop8h 28m
Alaska Airlines
Deal found 3/12![Alaska Airlines logo]()
$138
This Alaska Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/148:00 am
ORD
- BOI
1 stop8h 29m
Alaska Airlines
Deal found 3/12![Alaska Airlines logo]()
$139
This Alaska Airlines deal was found by Cheapflights users on 3/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/285:52 pm
ORD
- GEG
1 stop7h 19m
Alaska Airlines
Deal found 3/14![Alaska Airlines logo]()
$139
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 March 17, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $240 (Frontier) |
One-way from | $114 (Kiwi.com) |
Popular in | June |
Cheapest in | February |
Average price | $397 |
Good round-trip deal | $281 or less |
Good one-way deal | $239 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 March 17, 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
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Tue 4/7
3:50 pm-10:57 pm
1 stop8h 07m
Boise Air Term. Gowen Fld
Wed 4/8
2:22 pm-11:59 pm
1 stop8h 37m
$277
ChicagoSpokane
ORD - GEG
ORDGEG
Chicago O'Hare Intl
Tue 4/28
5:52 pm-11:11 pm
1 stop7h 19m
Spokane
Sat 5/2
2:45 pm-11:59 pm
1 stop7h 14m
$277
ChicagoBoise
ORD - BOI
ORDBOI
Chicago O'Hare Intl
Fri 4/10
4:10 pm-11:47 pm
1 stop8h 37m
Boise Air Term. Gowen Fld
Tue 4/14
2:22 pm-11:59 pm
1 stop8h 37m
$283
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Tue 4/7
6:12 pm-10:11 pm
1 stop4h 59m
Boise Air Term. Gowen Fld
Sat 4/11
8:00 am-2:43 pm
1 stop5h 43m
$297
ChicagoBoise
MDW - BOI
MDWBOI
Chicago Midway
Fri 5/29
6:25 pm-12:45 am
1 stop7h 20m
Boise Air Term. Gowen Fld
Fri 6/5
8:45 am-1:05 pm
Nonstop3h 20m
$299
ChicagoBoise
ORD - BOI
ORDBOI
Chicago O'Hare Intl
Fri 5/15
6:20 pm-11:55 pm
1 stop6h 35m
Boise Air Term. Gowen Fld
Mon 5/25
11:39 pm-10:16 am
1 stop9h 37m
$309
ChicagoBoise
MDW - BOI
MDWBOI
Chicago Midway
Fri 4/10
5:15 pm-1:00 am
2 stops8h 45m
Boise Air Term. Gowen Fld
Mon 4/13
4:20 pm-11:40 pm
1 stop6h 20m
$314
ChicagoBoise
ORD - BOI
ORDBOI
Chicago O'Hare Intl
Thu 4/9
7:25 am-4:03 pm
1 stop9h 38m
Boise Air Term. Gowen Fld
Thu 4/16
8:30 am-9:25 pm
2 stops11h 55m
$314
ChicagoBoise
ORD - BOI
ORDBOI
Chicago O'Hare Intl
Sat 5/23
5:41 pm-11:46 pm
1 stop7h 05m
Boise Air Term. Gowen Fld
Mon 5/25
11:39 pm-10:27 am
2 stops9h 48m
$314
ChicagoSpokane
ORD - GEG
ORDGEG
Chicago O'Hare Intl
Fri 4/24
4:35 pm-6:51 pm
Nonstop4h 16m
Spokane
Sun 4/26
1:46 pm-11:28 pm
1 stop7h 42m
$319
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.
STL-BOI
ORD-BOI
ORD-GEG
MDW-BOI
ORD-JAC
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
STL-BOI
ORD-BOI
ORD-GEG
MDW-BOI
What is the cheapest month to book a flight from Illinois to Idaho?
Currently, July is the cheapest month in which you can book a flight from Illinois to Idaho (average of $158). Flying from Illinois to Idaho in March is currently the most expensive (average of $383). 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 March 17, 2026.
It’s typically best to fly out from Illinois to Idaho at noon. Doing so could potentially save you 27% 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 March 17, 2026.
The most flights from USIL to USID are scheduled on a Monday (6 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (6 on average).
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 March 17, 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.
Boarding
8.1
Comfort
8.0
Entertainment
7.5
Crew
8.6
Overall
8.0
Food
7.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
Boarding
8.1
Comfort
8.0
Entertainment
7.5
Crew
8.6
Overall
8.0
Food
7.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
Boarding
8.1
Comfort
8.0
Entertainment
7.5
Crew
8.6
Overall
8.0
Food
7.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
Boarding
8.1
Comfort
8.0
Entertainment
7.5
Crew
8.6
Overall
8.0
Food
7.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
Boarding
8.1
Comfort
8.0
Entertainment
7.5
Crew
8.6
Overall
8.0
Food
7.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
Boarding
8.1
Comfort
8.0
Entertainment
7.5
Crew
8.6
Overall
8.0
Food
7.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
Related info for your journey
Find useful and relevant information for your journey from 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 March 17, 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 4 airlines flying from Illinois to Idaho
Discover the top 4 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 March 17, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$174 | Average$327 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$248 | Average$477 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$254 | Average$368 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$255 | Average$450 | FlexibilityNo cancel fee | On-time71% |