$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 25 — Jun 11
Round-trip
1 adult, Economy
We work with more than 300 partners to bring you better travel deals
Find cheap flights from Illinois to Idaho with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.3. Compare prices and book
Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheap flight deals from Illinois to Idaho
Cheapest
Best
Last-minute
One-way
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 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 April 25, 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 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 4/23. 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 8/127:50 am
MDW
- BOI
2 stops12h 55m
Southwest
Wed 8/193:40 pm
BOI
- MDW
1 stop13h 10m
Southwest
Deal found 4/23![Southwest logo]()
$238
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 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 April 25, 2026.
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.
Thu 9/107:10 am
MDW
- GEG
1 stop8h 05m
Southwest
Tue 9/297:30 am
GEG
- MDW
2 stops9h 30m
Southwest
Deal found 4/23![Southwest logo]()
$263
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 6/205:00 am
ORD
- IDA
1 stop5h 50m
United Airlines
Sat 6/275:54 pm
IDA
- ORD
1 stop5h 50m
United Airlines
Deal found 4/22![United Airlines logo]()
$302
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.
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 4/21![Alaska Airlines logo]()
$305
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/16:55 am
ORD
- GEG
1 stop6h 57m
Delta
Wed 7/87:08 pm
GEG
- ORD
2 stops10h 51m
Delta
Deal found 4/24![Delta logo]()
$331
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.
Thu 8/136:15 am
MDW
- GEG
1 stop12h 40m
Southwest
Tue 8/187:30 am
GEG
- MDW
2 stops9h 30m
Southwest
Deal found 4/21![Southwest logo]()
$268
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 4/20. 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 4/24. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/88:40 am
ORD
- BOI
Nonstop3h 52m
United Airlines
Sat 8/152:44 pm
BOI
- ORD
1 stop5h 58m
United Airlines
Deal found 4/24![United Airlines logo]()
$347
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 9/126:45 am
MDW
- GEG
2 stops9h 50m
Southwest
Wed 9/164:55 pm
GEG
- MDW
1 stop10h 05m
Southwest
Deal found 4/23![Southwest logo]()
$318
This Alaska Airlines 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 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 6/21:59 pm
GEG
- ORD
1 stop7h 00m
Alaska Airlines
Deal found 4/24![Alaska Airlines logo]()
$321
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/88:27 am
ORD
- BOI
2 stops11h 33m
Delta
Sat 8/155:40 am
BOI
- ORD
1 stop4h 49m
Delta
Deal found 4/24![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.
Fri 7/248:40 am
ORD
- BOI
Nonstop3h 52m
United Airlines
Fri 7/3112:38 pm
BOI
- ORD
Nonstop3h 34m
United Airlines
Deal found 4/22![United Airlines 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 9/16:00 am
ORD
- BOI
1 stop7h 35m
Alaska Airlines
Wed 9/22:16 pm
BOI
- ORD
1 stop8h 43m
Alaska Airlines
Deal found 4/21![Alaska Airlines logo]()
$335
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/162:07 pm
ORD
- GEG
2 stops11h 52m
Delta
Wed 6/171:19 pm
GEG
- ORD
1 stop6h 38m
Delta
Deal found 4/22![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 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 5/295:41 pm
ORD
- GEG
2 stops7h 54m
Delta
Sat 6/65:00 am
GEG
- ORD
1 stop6h 52m
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.
Thu 7/25:00 am
ORD
- BOI
1 stop5h 53m
United Airlines
Tue 7/75:46 pm
BOI
- ORD
1 stop5h 58m
United Airlines
Deal found 4/22![United Airlines logo]()
$377
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 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 4/22. 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 7/2212:27 pm
ORD
- BOI
2 stops11h 03m
Delta
Wed 7/296:42 pm
BOI
- ORD
2 stops12h 17m
Delta
Deal found 4/22![Delta logo]()
$345
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 4/24. 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.
Wed 7/155:54 pm
ORD
- GEG
2 stops8h 01m
Delta
Tue 7/215:41 am
GEG
- ORD
2 stops11h 49m
Delta
Deal found 4/24![Delta logo]()
$345
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.
Tue 9/19:00 am
STL
- BOI
2 stops8h 48m
United Airlines
Wed 9/210:37 am
BOI
- STL
1 stop4h 54m
United Airlines
Deal found 4/22![United Airlines logo]()
$388
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/245:35 am
MDW
- BOI
2 stops10h 05m
Southwest
Mon 6/294:25 pm
BOI
- MDW
1 stop6h 45m
Southwest
Deal found 4/24![Southwest logo]()
$402
This Alaska Airlines 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/207:20 am
ORD
- IDA
1 stop6h 46m
Alaska Airlines
Sat 7/254:14 pm
IDA
- ORD
1 stop11h 46m
Alaska Airlines
Deal found 4/24![Alaska Airlines logo]()
$429
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/37:13 pm
MDW
- BOI
1 stop6h 35m
Delta
Sun 6/711:45 pm
BOI
- MDW
1 stop9h 22m
Delta
Deal found 4/22![Delta logo]()
$355
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 7/259:00 am
ORD
- IDA
Nonstop3h 45m
United Airlines
Sat 8/15:54 pm
IDA
- ORD
1 stop5h 50m
United Airlines
Deal found 4/22![United Airlines logo]()
$395
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/245:45 pm
MDW
- BOI
1 stop6h 40m
Southwest
Sun 5/313:25 pm
BOI
- MDW
1 stop8h 25m
Southwest
Deal found 4/24![Southwest logo]()
$407
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 7/77:06 pm
MDW
- BOI
1 stop5h 40m
Delta
Sun 7/1211:42 pm
BOI
- MDW
1 stop9h 21m
Delta
Deal found 4/20![Delta logo]()
$355
This Alaska Airlines 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/47:41 pm
STL
- BOI
1 stop16h 22m
Alaska Airlines
Sun 6/79:00 am
BOI
- STL
1 stop6h 37m
Alaska Airlines
Deal found 4/24![Alaska Airlines logo]()
$452
Last-minute flights from Illinois to IdahoDiscover last-minute flight deals from Illinois to Idaho. Data last updated April 25, 2026 and is based on user searches.
Discover last-minute flight deals from Illinois to Idaho. Data last updated April 25, 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 25, 2026.
Search for one-way flight options from Illinois to Idaho. Find affordable one-way fares based on user searches. Data last updated April 25, 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 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 Kiwi.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 Kiwi.com 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]()
$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 25, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $221 (Southwest) |
One-way from | $109 (Trip.com) |
Popular in | November |
Cheapest in | February |
Average price | $372 |
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 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
ChicagoSpokane
MDW - GEG
MDWGEG
Chicago Midway
Thu 9/10
7:10 am-1:15 pm
1 stop8h 05m
Spokane
Tue 9/29
7:30 am-7:00 pm
2 stops9h 30m
$263
ChicagoSpokane
MDW - GEG
MDWGEG
Chicago Midway
Thu 8/13
6:15 am-4:55 pm
1 stop12h 40m
Spokane
Tue 8/18
7:30 am-7:00 pm
2 stops9h 30m
$268
ChicagoIdaho Falls
ORD - IDA
ORDIDA
Chicago O'Hare Intl
Sat 6/20
5:00 am-9:50 am
1 stop5h 50m
Idaho Falls Fanning Field
Sat 6/27
5:54 pm-12:44 am
1 stop5h 50m
$302
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
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
ChicagoSpokane
MDW - GEG
MDWGEG
Chicago Midway
Sat 9/12
6:45 am-2:35 pm
2 stops9h 50m
Spokane
Wed 9/16
4:55 pm-5:00 am
1 stop10h 05m
$318
ChicagoSpokane
ORD - GEG
ORDGEG
Chicago O'Hare Intl
Sat 5/30
9:00 am-9:45 pm
1 stop14h 45m
Spokane
Tue 6/2
1:59 pm-10:59 pm
1 stop7h 00m
$321
ChicagoSpokane
ORD - GEG
ORDGEG
Chicago O'Hare Intl
Wed 7/1
6:55 am-11:52 am
1 stop6h 57m
Spokane
Wed 7/8
7:08 pm-7:59 am
2 stops10h 51m
$331
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
ChicagoBoise
ORD - BOI
ORDBOI
Chicago O'Hare Intl
Tue 9/1
6:00 am-12:35 pm
1 stop7h 35m
Boise Air Term. Gowen Fld
Wed 9/2
2:16 pm-11:59 pm
1 stop8h 43m
$335
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-BOI
ORD-GEG
MDW-BOI
MDW-GEG
STL-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
ORD-BOI
ORD-GEG
MDW-BOI
MDW-GEG
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 25, 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 25, 2026.
The most flights from USIL to USID are scheduled on a Monday (7 on average). You will have fewer flight options on Thursday, 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 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.
Entertainment
7.5
Comfort
8.0
Food
7.0
Overall
8.0
Boarding
8.1
Crew
8.6
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Entertainment
7.5
Comfort
8.0
Food
7.0
Overall
8.0
Boarding
8.1
Crew
8.6
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Entertainment
7.5
Comfort
8.0
Food
7.0
Overall
8.0
Boarding
8.1
Crew
8.6
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Entertainment
7.5
Comfort
8.0
Food
7.0
Overall
8.0
Boarding
8.1
Crew
8.6
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Entertainment
7.5
Comfort
8.0
Food
7.0
Overall
8.0
Boarding
8.1
Crew
8.6
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Entertainment
7.5
Comfort
8.0
Food
7.0
Overall
8.0
Boarding
8.1
Crew
8.6
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
Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.
Alternative routes
Complete your trip
Flights by cabin class
Other flight options
Popular flights
Return Flight Options
Top destinations
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 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 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 25, 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% |