$109+ 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 5/13. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — BOI
May 24 — May 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 April 24, 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 April 24, 2026.
This Southwest deal was found by Cheapflights users on 4/22. 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 8/1810:20 am
MDW
- GEG
1 stop7h 55m
Southwest
Tue 8/254:55 pm
GEG
- MDW
1 stop10h 05m
Southwest
Deal found 4/22![Southwest logo]()
$221
This Southwest deal was found by Cheapflights users on 4/23. 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.
Wed 8/126:40 am
MDW
- BOI
1 stop5h 15m
Southwest
Wed 8/193:40 pm
BOI
- MDW
1 stop13h 10m
Southwest
Deal found 4/23![Southwest logo]()
$227
This CheapOair deal was found by Cheapflights users on 4/21. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/139:37 pm
ORD
- BOI
1 stop15h 50m
Frontier
Sun 5/171:22 pm
BOI
- ORD
1 stop6h 10m
Frontier
Deal found 4/21![Frontier logo]()
$236
This Southwest deal was found by Cheapflights users on 4/20. 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.
Sat 5/306:00 am
MDW
- BOI
1 stop5h 25m
Southwest
Tue 6/24:05 pm
BOI
- MDW
1 stop6h 15m
Southwest
Deal found 4/20![Southwest logo]()
$243
This Southwest deal was found by Cheapflights users on 4/20. 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.
Thu 8/138:50 pm
MDW
- GEG
Nonstop3h 50m
Southwest
Tue 8/184:55 pm
GEG
- MDW
1 stop10h 05m
Southwest
Deal found 4/20![Southwest logo]()
$248
This Southwest deal was found by Cheapflights users on 4/23. 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.
Sat 9/125:40 am
MDW
- GEG
1 stop7h 05m
Southwest
Wed 9/164:55 pm
GEG
- MDW
1 stop10h 05m
Southwest
Deal found 4/23![Southwest logo]()
$258
This CheapOair deal was found by Cheapflights users on 4/20. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/239:37 pm
ORD
- BOI
1 stop15h 53m
Frontier
Tue 5/261:25 pm
BOI
- ORD
1 stop6h 07m
Frontier
Deal found 4/20![Frontier logo]()
$261
This American Airlines deal was found by Cheapflights users on 4/20. 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.
Tue 6/27:00 am
STL
- BOI
1 stop8h 20m
American Airlines
Tue 6/93:11 pm
BOI
- STL
1 stop7h 45m
American Airlines
Deal found 4/20![American Airlines logo]()
$263
This Southwest deal was found by Cheapflights users on 4/20. 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.
Thu 9/36:15 am
MDW
- GEG
1 stop12h 40m
Southwest
Wed 9/94:55 pm
GEG
- MDW
1 stop10h 05m
Southwest
Deal found 4/20![Southwest logo]()
$263
This Southwest deal was found by Cheapflights users on 4/20. 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.
Sat 8/155:40 am
MDW
- BOI
1 stop8h 20m
Southwest
Mon 8/1712:10 pm
BOI
- MDW
Nonstop3h 20m
Southwest
Deal found 4/20![Southwest logo]()
$269
This Expedia deal was found by Cheapflights users on 4/22. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/22:10 pm
ORD
- GEG
1 stop9h 35m
Multiple Airlines
Fri 6/1212:28 pm
GEG
- ORD
1 stop6h 15m
Multiple Airlines
Deal found 4/22![Multiple Airlines logo]()
$273
This Southwest deal was found by Cheapflights users on 4/21. 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.
Wed 8/124:40 pm
MDW
- GEG
2 stops7h 45m
Southwest
Sat 8/151:40 pm
GEG
- MDW
1 stop6h 35m
Southwest
Deal found 4/21![Southwest logo]()
$274
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 April 24, 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 April 24, 2026.
This Alaska Airlines deal was found by Cheapflights users on 4/22. 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 8/227:00 am
ORD
- GEG
1 stop6h 52m
Alaska Airlines
Sat 8/297:00 am
GEG
- ORD
1 stop14h 57m
Alaska Airlines
Deal found 4/22![Alaska Airlines logo]()
$305
This Southwest deal was found by Cheapflights users on 4/22. 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 8/45:00 pm
STL
- BOI
1 stop7h 20m
Southwest
Tue 8/182:20 pm
BOI
- STL
1 stop7h 25m
Southwest
Deal found 4/22![Southwest logo]()
$335
This Delta deal was found by Cheapflights users on 4/20. 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.
Tue 5/265:41 pm
ORD
- GEG
1 stop7h 25m
Delta
Thu 5/281:11 pm
GEG
- ORD
1 stop8h 46m
Delta
Deal found 4/20![Delta logo]()
$335
This United Airlines deal was found by Cheapflights users on 4/23. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/28:40 am
ORD
- BOI
Nonstop3h 52m
United Airlines
Tue 7/75:46 pm
BOI
- ORD
1 stop5h 58m
United Airlines
Deal found 4/23![United Airlines logo]()
$345
This Alaska Airlines deal was found by Cheapflights users on 4/23. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/309:00 am
ORD
- GEG
1 stop14h 45m
Alaska Airlines
Tue 6/27:01 am
GEG
- ORD
1 stop9h 49m
Alaska Airlines
Deal found 4/23![Alaska Airlines logo]()
$305
This Alaska Airlines deal was found by Cheapflights users on 4/21. 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 6/22:10 pm
ORD
- GEG
1 stop9h 35m
Alaska Airlines
Thu 6/47:01 am
GEG
- ORD
1 stop14h 54m
Alaska Airlines
Deal found 4/21![Alaska Airlines logo]()
$305
This Delta deal was found by Cheapflights users on 4/19. 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.
Tue 6/167:45 am
ORD
- GEG
2 stops9h 57m
Delta
Wed 6/171:19 pm
GEG
- ORD
1 stop6h 38m
Delta
Deal found 4/19![Delta logo]()
$340
This Southwest deal was found by Cheapflights users on 4/22. 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.
Thu 7/24:55 pm
MDW
- BOI
1 stop9h 10m
Southwest
Tue 7/74:05 pm
BOI
- MDW
1 stop5h 20m
Southwest
Deal found 4/22![Southwest logo]()
$355
This United Airlines deal was found by Cheapflights users on 4/19. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/233:47 pm
ORD
- BOI
1 stop7h 18m
United Airlines
Sun 5/315:46 pm
BOI
- ORD
1 stop5h 58m
United Airlines
Deal found 4/19![United Airlines logo]()
$355
This Alaska Airlines deal was found by Cheapflights users on 4/23. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/127:59 pm
ORD
- GEG
1 stop29h 08m
Alaska Airlines
Sat 8/227:00 am
GEG
- ORD
1 stop14h 57m
Alaska Airlines
Deal found 4/23![Alaska Airlines logo]()
$308
This Delta deal was found by Cheapflights users on 4/19. 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 5/296:20 pm
ORD
- GEG
1 stop6h 31m
Delta
Sat 6/65:39 pm
GEG
- ORD
2 stops12h 26m
Delta
Deal found 4/19![Delta logo]()
$340
This United Airlines deal was found by Cheapflights users on 4/19. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/195:00 am
ORD
- BOI
1 stop5h 45m
United Airlines
Sat 6/275:46 pm
BOI
- ORD
1 stop5h 58m
United Airlines
Deal found 4/19![United Airlines logo]()
$355
This Southwest deal was found by Cheapflights users on 4/20. 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.
Sat 5/166:15 am
MDW
- GEG
1 stop8h 10m
Southwest
Tue 5/197:00 am
GEG
- MDW
1 stop6h 55m
Southwest
Deal found 4/20![Southwest logo]()
$361
This Delta deal was found by Cheapflights users on 4/20. 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 5/297:13 pm
MDW
- GEG
1 stop5h 53m
Delta
Sat 6/66:10 am
GEG
- MDW
2 stops9h 46m
Delta
Deal found 4/20![Delta logo]()
$340
This United Airlines deal was found by Cheapflights users on 4/22. 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.
Sat 6/209:00 am
ORD
- IDA
Nonstop3h 45m
United Airlines
Sat 6/275:54 pm
IDA
- ORD
1 stop5h 50m
United Airlines
Deal found 4/22![United Airlines logo]()
$364
This Alaska Airlines deal was found by Cheapflights users on 4/20. 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 5/265:33 pm
STL
- GEG
1 stop7h 33m
Alaska Airlines
Wed 5/275:00 am
GEG
- STL
1 stop8h 16m
Alaska Airlines
Deal found 4/20![Alaska Airlines logo]()
$341
This Southwest deal was found by Cheapflights users on 4/19. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/165:30 am
MDW
- BOI
1 stop5h 35m
Southwest
Tue 6/237:10 am
BOI
- MDW
Nonstop3h 20m
Southwest
Deal found 4/19![Southwest logo]()
$377
This Delta deal was found by Cheapflights users on 4/21. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/318:55 am
ORD
- JAC
2 stops11h 02m
Delta
Fri 9/41:10 pm
JAC
- ORD
1 stop7h 48m
Delta
Deal found 4/21![Delta logo]()
$344
This United Airlines deal was found by Cheapflights users on 4/22. 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.
Sun 5/249:05 am
ORD
- JAC
Nonstop3h 30m
United Airlines
Sun 5/314:23 pm
JAC
- ORD
1 stop7h 21m
United Airlines
Deal found 4/22![United Airlines logo]()
$365
This Southwest deal was found by Cheapflights users on 4/21. 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.
Fri 6/55:15 am
MDW
- GEG
1 stop5h 55m
Southwest
Fri 6/1212:55 pm
GEG
- MDW
1 stop8h 30m
Southwest
Deal found 4/21![Southwest logo]()
$378
This Alaska Airlines deal was found by Cheapflights users on 4/22. 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.
Thu 5/282:10 pm
ORD
- BOI
1 stop9h 27m
Alaska Airlines
Sun 5/318:51 pm
BOI
- ORD
1 stop8h 29m
Alaska Airlines
Deal found 4/22![Alaska Airlines logo]()
$347
This Delta deal was found by Cheapflights users on 4/23. 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.
Thu 5/287:13 pm
MDW
- BOI
1 stop5h 33m
Delta
Sun 5/315:20 am
BOI
- MDW
1 stop6h 59m
Delta
Deal found 4/23![Delta logo]()
$355
This Southwest deal was found by Cheapflights users on 4/19. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/315:20 am
MDW
- BOI
1 stop7h 25m
Southwest
Mon 8/3112:10 pm
BOI
- MDW
Nonstop3h 20m
Southwest
Deal found 4/19![Southwest logo]()
$387
This United Airlines deal was found by Cheapflights users on 4/20. 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.
Thu 6/255:00 am
ORD
- IDA
1 stop5h 50m
United Airlines
Mon 6/294:10 pm
IDA
- ORD
1 stop5h 39m
United Airlines
Deal found 4/20![United Airlines logo]()
$388
This Delta deal was found by Cheapflights users on 4/23. 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.
Thu 5/287:13 pm
MDW
- BOI
1 stop5h 33m
Delta
Mon 6/15:20 am
BOI
- MDW
1 stop6h 59m
Delta
Deal found 4/23![Delta logo]()
$355
This Alaska Airlines deal was found by Cheapflights users on 4/21. 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 9/13:00 pm
STL
- BOI
1 stop9h 44m
Alaska Airlines
Wed 9/26:20 am
BOI
- STL
1 stop6h 44m
Alaska Airlines
Deal found 4/21![Alaska Airlines logo]()
$358
This United Airlines deal was found by Cheapflights users on 4/20. 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.
Tue 9/19:00 am
STL
- BOI
2 stops8h 48m
United Airlines
Wed 9/212:23 pm
BOI
- STL
1 stop7h 59m
United Airlines
Deal found 4/20![United Airlines logo]()
$388
This Delta deal was found by Cheapflights users on 4/23. 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 7/76:05 am
MDW
- BOI
1 stop7h 48m
Delta
Sun 7/1211:42 pm
BOI
- MDW
1 stop9h 21m
Delta
Deal found 4/23![Delta logo]()
$355
This Southwest deal was found by Cheapflights users on 4/22. 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.
Sat 5/306:15 am
MDW
- GEG
1 stop8h 10m
Southwest
Thu 6/49:50 am
GEG
- MDW
1 stop13h 35m
Southwest
Deal found 4/22![Southwest logo]()
$393
This Alaska Airlines deal was found by Cheapflights users on 4/22. 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.
Mon 9/211:03 pm
ORD
- IDA
1 stop10h 53m
Alaska Airlines
Sat 9/266:18 am
IDA
- ORD
1 stop7h 52m
Alaska Airlines
Deal found 4/22![Alaska Airlines logo]()
$374
Last-minute flights from Illinois to IdahoDiscover last-minute flight deals from Illinois to Idaho. Data last updated April 24, 2026 and is based on user searches.
Discover last-minute flight deals from Illinois to Idaho. Data last updated April 24, 2026 and is based on user searches.
This CheapOair deal was found by Cheapflights users on 4/21. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/139:37 pm
ORD
- BOI
1 stop15h 50m
Frontier
Sun 5/171:22 pm
BOI
- ORD
1 stop6h 10m
Frontier
Deal found 4/21![Frontier logo]()
$236
This CheapOair deal was found by Cheapflights users on 4/20. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/239:37 pm
ORD
- BOI
1 stop15h 53m
Frontier
Tue 5/261:25 pm
BOI
- ORD
1 stop6h 07m
Frontier
Deal found 4/20![Frontier logo]()
$261
This Alaska Airlines deal was found by Cheapflights users on 4/23. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/239:00 am
ORD
- GEG
1 stop14h 45m
Alaska Airlines
Sat 5/307:01 am
GEG
- ORD
1 stop9h 49m
Alaska Airlines
Deal found 4/23![Alaska Airlines logo]()
$295
This Kiwi.com deal was found by Cheapflights users on 4/21. 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 5/279:37 pm
ORD
- BOI
1 stop15h 53m
Frontier
Thu 6/41:25 pm
BOI
- ORD
2 stops17h 30m
Frontier
Deal found 4/21![Frontier logo]()
$279
This Kiwi.com deal was found by Cheapflights users on 4/21. 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 5/279:37 pm
ORD
- BOI
1 stop15h 53m
Frontier
Tue 6/91:25 pm
BOI
- ORD
2 stops34h 23m
Frontier
Deal found 4/21![Frontier logo]()
$292
This Southwest deal was found by Cheapflights users on 4/20. 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.
Thu 5/284:35 pm
MDW
- GEG
2 stops9h 55m
Southwest
Tue 6/22:40 pm
GEG
- MDW
1 stop12h 45m
Southwest
Deal found 4/20![Southwest logo]()
$268
This Southwest deal was found by Cheapflights users on 4/20. 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.
Thu 5/284:50 pm
ORD
- GEG
1 stop9h 45m
Southwest
Tue 6/25:10 am
GEG
- ORD
1 stop6h 45m
Southwest
Deal found 4/20![Southwest logo]()
$278
This Expedia deal was found by Cheapflights users on 4/20. 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.
Thu 5/282:10 pm
ORD
- GEG
1 stop9h 35m
Multiple Airlines
Mon 6/112:33 pm
GEG
- ORD
1 stop5h 59m
Multiple Airlines
Deal found 4/20![Multiple Airlines logo]()
$293
This Alaska Airlines deal was found by Cheapflights users on 4/21. 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.
Thu 5/282:10 pm
ORD
- GEG
1 stop9h 35m
Alaska Airlines
Tue 6/27:01 am
GEG
- ORD
1 stop28h 13m
Alaska Airlines
Deal found 4/21![Alaska Airlines logo]()
$298
This Alaska Airlines deal was found by Cheapflights users on 4/21. 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.
Fri 5/299:00 am
ORD
- GEG
1 stop14h 45m
Alaska Airlines
Sat 6/67:01 am
GEG
- ORD
1 stop14h 54m
Alaska Airlines
Deal found 4/21![Alaska Airlines logo]()
$305
This Southwest deal was found by Cheapflights users on 4/20. 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.
Sat 5/306:00 am
MDW
- BOI
1 stop5h 25m
Southwest
Tue 6/24:05 pm
BOI
- MDW
1 stop6h 15m
Southwest
Deal found 4/20![Southwest logo]()
$243
This Southwest deal was found by Cheapflights users on 4/20. 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.
Sat 5/304:15 pm
ORD
- BOI
1 stop6h 50m
Southwest
Tue 6/24:05 pm
BOI
- ORD
1 stop6h 50m
Southwest
Deal found 4/20![Southwest logo]()
$278
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 April 24, 2026.
Search for one-way flight options from Illinois to Idaho. Find affordable one-way fares based on user searches. Data last updated April 24, 2026.
This Trip.com deal was found by Cheapflights users on 4/24. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/139:37 pm
ORD
- BOI
1 stop15h 50m
Frontier
Deal found 4/24![Frontier logo]()
$109
This Southwest deal was found by Cheapflights users on 4/20. 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.
Tue 6/24:50 pm
ORD
- BOI
1 stop8h 35m
Southwest
Deal found 4/20![Southwest logo]()
$111
This Southwest deal was found by Cheapflights users on 4/20. 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 6/34:50 pm
ORD
- GEG
1 stop8h 35m
Southwest
Deal found 4/20![Southwest logo]()
$111
This Trip.com deal was found by Cheapflights users on 4/20. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/99:37 pm
ORD
- BOI
1 stop15h 50m
Frontier
Deal found 4/20![Frontier logo]()
$115
This CheapOair deal was found by Cheapflights users on 4/21. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/209:37 pm
ORD
- BOI
1 stop15h 53m
Frontier
Deal found 4/21![Frontier logo]()
$117
This CheapOair deal was found by Cheapflights users on 4/20. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/278:08 pm
STL
- BOI
1 stop17h 22m
Frontier
Deal found 4/20![Frontier logo]()
$117
This Southwest deal was found by Cheapflights users on 4/20. 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.
Tue 6/24:00 pm
MDW
- BOI
2 stops9h 25m
Southwest
Deal found 4/20![Southwest logo]()
$128
This Southwest deal was found by Cheapflights users on 4/20. 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 6/34:00 pm
MDW
- GEG
2 stops9h 25m
Southwest
Deal found 4/20![Southwest logo]()
$128
This Southwest deal was found by Cheapflights users on 4/21. 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.
Tue 5/194:50 pm
ORD
- GEG
1 stop8h 35m
Southwest
Deal found 4/21![Southwest logo]()
$132
This Kiwi.com deal was found by Cheapflights users on 4/21. 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.
Sat 5/239:37 pm
ORD
- BOI
1 stop15h 53m
Frontier
Deal found 4/21![Frontier logo]()
$134
This Southwest deal was found by Cheapflights users on 4/21. 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.
Tue 5/124:50 pm
ORD
- BOI
1 stop8h 35m
Southwest
Deal found 4/21![Southwest logo]()
$137
This Kiwi.com deal was found by Cheapflights users on 4/23. 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.
Tue 5/199:37 pm
ORD
- GEG
2 stops48h 18m
Multiple Airlines
Deal found 4/23![Multiple 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 April 24, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $227 (Southwest) |
One-way from | $109 (Trip.com) |
Popular in | November |
Cheapest in | February |
Average price | $370 |
Good round-trip deal | $369 or less |
Good one-way deal | $201 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 April 24, 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
ChicagoSpokane
ORD - GEG
ORDGEG
Chicago O'Hare Intl
Sat 8/22
7:00 am-11:52 am
1 stop6h 52m
Spokane
Sat 8/29
7:00 am-11:57 pm
1 stop14h 57m
$305
ChicagoSpokane
ORD - GEG
ORDGEG
Chicago O'Hare Intl
Sat 5/30
9:00 am-9:45 pm
1 stop14h 45m
Spokane
Tue 6/2
7:01 am-6:50 pm
1 stop9h 49m
$305
ChicagoSpokane
ORD - GEG
ORDGEG
Chicago O'Hare Intl
Tue 6/2
2:10 pm-9:45 pm
1 stop9h 35m
Spokane
Thu 6/4
7:01 am-11:55 pm
1 stop14h 54m
$305
ChicagoSpokane
ORD - GEG
ORDGEG
Chicago O'Hare Intl
Wed 8/12
7:59 pm-11:07 pm
1 stop29h 08m
Spokane
Sat 8/22
7:00 am-11:57 pm
1 stop14h 57m
$308
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Tue 8/4
5:00 pm-11:20 pm
1 stop7h 20m
Boise Air Term. Gowen Fld
Tue 8/18
2:20 pm-10:45 pm
1 stop7h 25m
$335
ChicagoSpokane
ORD - GEG
ORDGEG
Chicago O'Hare Intl
Tue 5/26
5:41 pm-11:06 pm
1 stop7h 25m
Spokane
Thu 5/28
1:11 pm-11:57 pm
1 stop8h 46m
$335
ChicagoSpokane
ORD - GEG
ORDGEG
Chicago O'Hare Intl
Tue 6/16
7:45 am-3:42 pm
2 stops9h 57m
Spokane
Wed 6/17
1:19 pm-9:57 pm
1 stop6h 38m
$340
ChicagoSpokane
ORD - GEG
ORDGEG
Chicago O'Hare Intl
Fri 5/29
6:20 pm-10:51 pm
1 stop6h 31m
Spokane
Sat 6/6
5:39 pm-8:05 am
2 stops12h 26m
$340
ChicagoSpokane
MDW - GEG
MDWGEG
Chicago Midway
Fri 5/29
7:13 pm-11:06 pm
1 stop5h 53m
Spokane
Sat 6/6
6:10 am-5:56 pm
2 stops9h 46m
$340
St. LouisSpokane
STL - GEG
STLGEG
Lambert-St Louis
Tue 5/26
5:33 pm-11:06 pm
1 stop7h 33m
Spokane
Wed 5/27
5:00 am-3:16 pm
1 stop8h 16m
$341
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.
ORD-GEG
STL-BOI
ORD-BOI
MDW-BOI
MDW-GEG
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
ORD-GEG
STL-BOI
ORD-BOI
MDW-BOI
How far ahead should I book a flight from Illinois to Idaho?
The best time to book flights from Illinois to Idaho is 70 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.
What is the cheapest month to book a flight from Illinois to Idaho?
Currently, May is the cheapest month in which you can book a flight from Illinois to Idaho (average of $87). Flying from Illinois to Idaho 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 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 April 24, 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 April 24, 2026.
The most flights from USIL to USID are scheduled on a Monday (8 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (3 on average).
How much does it cost to fly round-trip from Illinois to Idaho?
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 April 24, 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
Entertainment
7.5
Comfort
8.0
Crew
8.6
Overall
8.0
Boarding
8.1
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Food
7.0
Entertainment
7.5
Comfort
8.0
Crew
8.6
Overall
8.0
Boarding
8.1
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Food
7.0
Entertainment
7.5
Comfort
8.0
Crew
8.6
Overall
8.0
Boarding
8.1
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Food
7.0
Entertainment
7.5
Comfort
8.0
Crew
8.6
Overall
8.0
Boarding
8.1
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Food
7.0
Entertainment
7.5
Comfort
8.0
Crew
8.6
Overall
8.0
Boarding
8.1
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Food
7.0
Entertainment
7.5
Comfort
8.0
Crew
8.6
Overall
8.0
Boarding
8.1
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
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.
Browse thousands of different options on Cheapflights for your next trip
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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 April 24, 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 April 24, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$174 | Average$337 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$249 | Average$490 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$254 | Average$378 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$268 | Average$440 | FlexibilityNo cancel fee | On-time71% |