$101+ Cheap flights from Idaho to Illinois
This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 4/26. Fares are subject to change and may not be available on all flights or dates of travel.
BOI — ORD
Apr 4 — Apr 111
Round-trip
1 adult, Economy
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Find cheap flights from Idaho to Illinois with Cheapflights
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Cheapest flights from Idaho to IllinoisExplore the most affordable flight options available from Idaho to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 5, 2026.
Explore the most affordable flight options available from Idaho to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 5, 2026.
This CheapOair deal was found by Cheapflights users on 3/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/912:03 pm
BOI
- STL
1 stop20h 45m
Frontier
Sat 4/188:17 pm
STL
- BOI
1 stop15h 51m
Frontier
Deal found 3/3![Frontier logo]()
$201
This Trip.com deal was found by Cheapflights users on 3/2. Clicking the “Pick Dates” 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.
Thu 4/168:28 pm
BOI
- ORD
1 stop9h 11m
Alaska Airlines
Thu 4/236:00 am
ORD
- BOI
1 stop8h 52m
Alaska Airlines
Deal found 3/2![Alaska Airlines logo]()
$214
This Alaska Airlines deal was found by Cheapflights users on 3/1. Clicking the “Pick Dates” 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 4/206:04 pm
BOI
- ORD
1 stop11h 35m
Alaska Airlines
Sat 5/26:00 am
ORD
- BOI
1 stop7h 35m
Alaska Airlines
Deal found 3/1![Alaska Airlines logo]()
$229
This Alaska Airlines deal was found by Cheapflights users on 3/3. Clicking the “Pick Dates” 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 4/157:43 pm
GEG
- ORD
1 stop8h 56m
Alaska Airlines
Wed 4/223:37 pm
ORD
- GEG
1 stop7h 54m
Alaska Airlines
Deal found 3/3![Alaska Airlines logo]()
$235
This Trip.com deal was found by Cheapflights users on 3/1. Clicking the “Pick Dates” 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.
Fri 5/17:41 pm
GEG
- ORD
1 stop8h 59m
Alaska Airlines
Tue 5/56:00 am
ORD
- GEG
1 stop9h 23m
Alaska Airlines
Deal found 3/1![Alaska Airlines logo]()
$240
This Kiwi.com deal was found by Cheapflights users on 3/3. Clicking the “Pick Dates” 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.
Thu 3/1212:15 pm
BOI
- STL
1 stop20h 34m
Frontier
Sat 3/148:12 pm
STL
- BOI
1 stop16h 08m
Frontier
Deal found 3/3![Frontier logo]()
$244
This Expedia deal was found by Cheapflights users on 3/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/273:12 pm
GEG
- ORD
1 stop6h 47m
Alaska Airlines
Tue 5/58:00 am
ORD
- GEG
1 stop7h 23m
Alaska Airlines
Deal found 3/5![Alaska Airlines logo]()
$246
This Alaska Airlines deal was found by Cheapflights users on 3/4. Clicking the “Pick Dates” 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 4/292:57 pm
BOI
- ORD
1 stop8h 02m
Alaska Airlines
Fri 5/18:48 pm
ORD
- BOI
1 stop13h 54m
Alaska Airlines
Deal found 3/4![Alaska Airlines logo]()
$249
This Kiwi.com deal was found by Cheapflights users on 3/4. Clicking the “Pick Dates” 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.
Sun 4/269:19 pm
GEG
- ORD
2 stops24h 08m
Multiple Airlines
Wed 4/298:58 pm
ORD
- GEG
1 stop25h 31m
Multiple Airlines
Deal found 3/4![Multiple Airlines logo]()
$249
This Southwest deal was found by Cheapflights users on 3/1. Clicking the “Pick Dates” 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 4/152:25 pm
GEG
- MDW
1 stop6h 55m
Southwest
Sat 4/186:00 am
MDW
- GEG
1 stop6h 05m
Southwest
Deal found 3/1![Southwest logo]()
$252
This Southwest deal was found by Cheapflights users on 3/1. Clicking the “Pick Dates” 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 4/152:25 pm
GEG
- ORD
1 stop7h 30m
Southwest
Sat 4/184:15 pm
ORD
- GEG
1 stop7h 20m
Southwest
Deal found 3/1![Southwest logo]()
$252
This Alaska Airlines deal was found by Cheapflights users on 3/2. Clicking the “Pick Dates” 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 4/147:19 am
GEG
- ORD
1 stop9h 21m
Alaska Airlines
Wed 4/226:00 am
ORD
- GEG
1 stop9h 23m
Alaska Airlines
Deal found 3/2![Alaska Airlines logo]()
$255
Best flights from Idaho to IllinoisDiscover carefully curated flight deals from Idaho to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated March 5, 2026.
Discover carefully curated flight deals from Idaho to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated March 5, 2026.
This Southwest deal was found by Cheapflights users on 3/1. Clicking the “Pick Dates” 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 4/152:25 pm
GEG
- MDW
1 stop6h 55m
Southwest
Sat 4/186:00 am
MDW
- GEG
1 stop6h 05m
Southwest
Deal found 3/1![Southwest logo]()
$252
This Alaska Airlines deal was found by Cheapflights users on 2/28. Clicking the “Pick Dates” 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 4/147:19 am
GEG
- ORD
1 stop9h 21m
Alaska Airlines
Wed 4/226:00 am
ORD
- GEG
1 stop9h 23m
Alaska Airlines
Deal found 2/28![Alaska Airlines logo]()
$255
This Delta deal was found by Cheapflights users on 3/1. Clicking the “Pick Dates” 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 3/315:30 am
BOI
- MDW
2 stops11h 24m
Delta
Tue 4/79:30 am
MDW
- BOI
1 stop5h 35m
Delta
Deal found 3/1![Delta logo]()
$274
This American Airlines deal was found by Cheapflights users on 3/2. Clicking the “Pick Dates” 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 4/216:00 am
GEG
- STL
1 stop9h 21m
American Airlines
Tue 4/289:34 am
STL
- GEG
1 stop9h 21m
American Airlines
Deal found 3/2![American Airlines logo]()
$277
This United Airlines deal was found by Cheapflights users on 3/4. Clicking the “Pick Dates” 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 6/411:09 am
GEG
- ORD
Nonstop3h 51m
United Airlines
Sat 6/68:05 pm
ORD
- GEG
Nonstop4h 25m
United Airlines
Deal found 3/4![United Airlines logo]()
$316
This Southwest deal was found by Cheapflights users on 3/1. Clicking the “Pick Dates” 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 4/152:25 pm
GEG
- ORD
1 stop7h 30m
Southwest
Sat 4/184:15 pm
ORD
- GEG
1 stop7h 20m
Southwest
Deal found 3/1![Southwest logo]()
$252
This Delta deal was found by Cheapflights users on 2/28. Clicking the “Pick Dates” 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 3/316:55 pm
IDA
- ORD
2 stops12h 35m
Delta
Sun 4/57:20 am
ORD
- IDA
1 stop6h 07m
Delta
Deal found 2/28![Delta logo]()
$274
This Southwest deal was found by Cheapflights users on 3/1. Clicking the “Pick Dates” 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 4/155:15 pm
BOI
- MDW
1 stop11h 10m
Southwest
Tue 4/215:35 pm
MDW
- BOI
1 stop6h 55m
Southwest
Deal found 3/1![Southwest logo]()
$275
This Delta deal was found by Cheapflights users on 3/1. Clicking the “Pick Dates” 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 5/610:41 am
BOI
- ORD
2 stops9h 37m
Delta
Mon 7/133:50 pm
ORD
- BOI
2 stops9h 06m
Delta
Deal found 3/1![Delta logo]()
$279
This Alaska Airlines deal was found by Cheapflights users on 3/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/119:55 am
GEG
- ORD
1 stop7h 57m
Alaska Airlines
Wed 5/132:10 pm
ORD
- GEG
1 stop9h 35m
Alaska Airlines
Deal found 3/5![Alaska Airlines logo]()
$326
This Southwest deal was found by Cheapflights users on 3/3. Clicking the “Pick Dates” 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 5/57:00 am
GEG
- MDW
1 stop8h 05m
Southwest
Wed 5/136:10 am
MDW
- GEG
1 stop9h 35m
Southwest
Deal found 3/3![Southwest logo]()
$275
This Delta deal was found by Cheapflights users on 3/1. Clicking the “Pick Dates” 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 3/315:30 am
BOI
- ORD
2 stops12h 04m
Delta
Tue 4/71:57 pm
ORD
- BOI
2 stops11h 02m
Delta
Deal found 3/1![Delta logo]()
$279
This United Airlines deal was found by Cheapflights users on 3/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/1512:04 pm
BOI
- ORD
Nonstop3h 50m
United Airlines
Fri 4/178:40 am
ORD
- BOI
Nonstop4h 09m
United Airlines
Deal found 3/3![United Airlines logo]()
$346
This Southwest deal was found by Cheapflights users on 3/2. Clicking the “Pick Dates” 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 4/216:00 am
BOI
- STL
1 stop6h 30m
Southwest
Sat 4/256:05 am
STL
- BOI
1 stop9h 05m
Southwest
Deal found 3/2![Southwest logo]()
$277
This Alaska Airlines deal was found by Cheapflights users on 3/1. Clicking the “Pick Dates” 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 5/74:06 pm
IDA
- ORD
1 stop6h 53m
Alaska Airlines
Tue 5/128:48 pm
ORD
- IDA
1 stop19h 38m
Alaska Airlines
Deal found 3/1![Alaska Airlines logo]()
$337
This Delta deal was found by Cheapflights users on 2/28. Clicking the “Pick Dates” 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 6/45:00 am
GEG
- ORD
1 stop6h 45m
Delta
Wed 6/106:00 pm
ORD
- GEG
1 stop7h 44m
Delta
Deal found 2/28![Delta logo]()
$282
This Southwest deal was found by Cheapflights users on 3/2. Clicking the “Pick Dates” 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 4/162:50 pm
GEG
- MDW
1 stop6h 50m
Southwest
Sun 4/195:10 am
MDW
- GEG
1 stop7h 25m
Southwest
Deal found 3/2![Southwest logo]()
$282
This United Airlines deal was found by Cheapflights users on 3/2. Clicking the “Pick Dates” 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 5/215:46 pm
BOI
- ORD
1 stop5h 58m
United Airlines
Mon 5/255:00 am
ORD
- BOI
1 stop5h 45m
United Airlines
Deal found 3/2![United Airlines logo]()
$379
This Delta deal was found by Cheapflights users on 3/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/165:00 am
GEG
- ORD
1 stop6h 23m
Delta
Wed 4/227:15 am
ORD
- GEG
1 stop7h 12m
Delta
Deal found 3/5![Delta logo]()
$286
This Alaska Airlines deal was found by Cheapflights users on 2/28. Clicking the “Pick Dates” 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 4/106:04 pm
BOI
- STL
1 stop28h 55m
Alaska Airlines
Thu 4/167:00 am
STL
- BOI
1 stop9h 29m
Alaska Airlines
Deal found 2/28![Alaska Airlines logo]()
$365
This Southwest deal was found by Cheapflights users on 3/1. Clicking the “Pick Dates” 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 5/12:50 pm
GEG
- MDW
1 stop6h 50m
Southwest
Tue 5/52:55 pm
MDW
- GEG
1 stop10h 00m
Southwest
Deal found 3/1![Southwest logo]()
$282
This United Airlines deal was found by Cheapflights users on 2/28. Clicking the “Pick Dates” 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 4/214:15 pm
JAC
- ORD
1 stop7h 15m
United Airlines
Sat 4/2510:49 am
ORD
- JAC
1 stop5h 35m
United Airlines
Deal found 2/28![United Airlines logo]()
$384
This Delta deal was found by Cheapflights users on 3/1. Clicking the “Pick Dates” 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 5/111:25 am
GEG
- ORD
2 stops7h 53m
Delta
Tue 5/511:00 am
ORD
- GEG
2 stops12h 05m
Delta
Deal found 3/1![Delta logo]()
$293
This Alaska Airlines deal was found by Cheapflights users on 3/3. Clicking the “Pick Dates” 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 4/94:15 pm
BOI
- STL
1 stop6h 44m
Alaska Airlines
Fri 4/177:00 am
STL
- BOI
1 stop7h 58m
Alaska Airlines
Deal found 3/3![Alaska Airlines logo]()
$377
This Southwest deal was found by Cheapflights users on 3/3. Clicking the “Pick Dates” 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 4/83:15 pm
BOI
- STL
1 stop5h 30m
Southwest
Sat 4/116:10 am
STL
- BOI
2 stops11h 05m
Southwest
Deal found 3/3![Southwest logo]()
$288
This United Airlines deal was found by Cheapflights users on 3/1. Clicking the “Pick Dates” 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 6/184:23 pm
JAC
- STL
1 stop6h 34m
United Airlines
Mon 6/221:38 pm
STL
- JAC
1 stop5h 16m
United Airlines
Deal found 3/1![United Airlines logo]()
$389
This Delta deal was found by Cheapflights users on 3/4. Clicking the “Pick Dates” 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 4/91:45 pm
BOI
- ORD
1 stop9h 07m
Delta
Thu 4/161:36 pm
ORD
- BOI
2 stops7h 53m
Delta
Deal found 3/4![Delta logo]()
$294
This American Airlines deal was found by Cheapflights users on 3/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/81:25 pm
JAC
- STL
1 stop8h 34m
American Airlines
Mon 5/118:03 pm
STL
- JAC
2 stops17h 38m
American Airlines
Deal found 3/1![American Airlines logo]()
$569
This United Airlines deal was found by Cheapflights users on 3/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/155:20 pm
IDA
- ORD
1 stop6h 10m
United Airlines
Sun 4/197:00 am
ORD
- IDA
1 stop7h 24m
United Airlines
Deal found 3/2![United Airlines logo]()
$393
This Southwest deal was found by Cheapflights users on 3/3. Clicking the “Pick Dates” 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 4/245:50 am
GEG
- ORD
1 stop11h 00m
Southwest
Mon 4/276:15 pm
ORD
- GEG
1 stop6h 05m
Southwest
Deal found 3/3![Southwest logo]()
$297
Last-minute flights from Idaho to IllinoisDiscover last-minute flight deals from Idaho to Illinois. Data last updated March 5, 2026 and is based on user searches.
Discover last-minute flight deals from Idaho to Illinois. Data last updated March 5, 2026 and is based on user searches.
This Kiwi.com deal was found by Cheapflights users on 3/3. Clicking the “Pick Dates” 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.
Thu 3/1212:15 pm
BOI
- STL
1 stop20h 34m
Frontier
Sat 3/148:12 pm
STL
- BOI
1 stop16h 08m
Frontier
Deal found 3/3![Frontier logo]()
$244
This CheapOair deal was found by Cheapflights users on 3/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/912:03 pm
BOI
- STL
1 stop20h 45m
Frontier
Sat 4/188:17 pm
STL
- BOI
1 stop15h 51m
Frontier
Deal found 3/3![Frontier logo]()
$201
This Alaska Airlines deal was found by Cheapflights users on 3/2. Clicking the “Pick Dates” 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 4/147:19 am
GEG
- ORD
1 stop9h 21m
Alaska Airlines
Wed 4/226:00 am
ORD
- GEG
1 stop9h 23m
Alaska Airlines
Deal found 3/2![Alaska Airlines logo]()
$255
This American Airlines deal was found by Cheapflights users on 3/4. Clicking the “Pick Dates” 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 4/141:22 pm
GEG
- ORD
Nonstop3h 57m
American Airlines
Wed 4/2210:30 am
ORD
- GEG
Nonstop4h 02m
American Airlines
Deal found 3/4![American Airlines logo]()
$257
This Alaska Airlines deal was found by Cheapflights users on 3/3. Clicking the “Pick Dates” 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 4/157:43 pm
GEG
- ORD
1 stop8h 56m
Alaska Airlines
Wed 4/223:37 pm
ORD
- GEG
1 stop7h 54m
Alaska Airlines
Deal found 3/3![Alaska Airlines logo]()
$235
This Southwest deal was found by Cheapflights users on 3/1. Clicking the “Pick Dates” 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 4/152:25 pm
GEG
- MDW
1 stop6h 55m
Southwest
Sat 4/186:00 am
MDW
- GEG
1 stop6h 05m
Southwest
Deal found 3/1![Southwest logo]()
$252
This Southwest deal was found by Cheapflights users on 3/1. Clicking the “Pick Dates” 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 4/152:25 pm
GEG
- ORD
1 stop7h 30m
Southwest
Sat 4/184:15 pm
ORD
- GEG
1 stop7h 20m
Southwest
Deal found 3/1![Southwest logo]()
$252
This Trip.com deal was found by Cheapflights users on 3/2. Clicking the “Pick Dates” 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.
Thu 4/168:28 pm
BOI
- ORD
1 stop9h 11m
Alaska Airlines
Thu 4/236:00 am
ORD
- BOI
1 stop8h 52m
Alaska Airlines
Deal found 3/2![Alaska Airlines logo]()
$214
This Alaska Airlines deal was found by Cheapflights users on 3/1. Clicking the “Pick Dates” 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 4/206:04 pm
BOI
- ORD
1 stop11h 35m
Alaska Airlines
Sat 5/26:00 am
ORD
- BOI
1 stop7h 35m
Alaska Airlines
Deal found 3/1![Alaska Airlines logo]()
$229
This Kiwi.com deal was found by Cheapflights users on 3/4. Clicking the “Pick Dates” 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.
Sun 4/269:19 pm
GEG
- ORD
2 stops24h 08m
Multiple Airlines
Wed 4/298:58 pm
ORD
- GEG
1 stop25h 31m
Multiple Airlines
Deal found 3/4![Multiple Airlines logo]()
$249
This Expedia deal was found by Cheapflights users on 3/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/273:12 pm
GEG
- ORD
1 stop6h 47m
Alaska Airlines
Tue 5/58:00 am
ORD
- GEG
1 stop7h 23m
Alaska Airlines
Deal found 3/5![Alaska Airlines logo]()
$246
This Alaska Airlines deal was found by Cheapflights users on 3/4. Clicking the “Pick Dates” 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 4/292:57 pm
BOI
- ORD
1 stop8h 02m
Alaska Airlines
Fri 5/18:48 pm
ORD
- BOI
1 stop13h 54m
Alaska Airlines
Deal found 3/4![Alaska Airlines logo]()
$249
One-way flights from Idaho to IllinoisSearch for one-way flight options from Idaho to Illinois. Find affordable one-way fares based on user searches. Data last updated March 5, 2026.
Search for one-way flight options from Idaho to Illinois. Find affordable one-way fares based on user searches. Data last updated March 5, 2026.
This Kiwi.com deal was found by Cheapflights users on 2/28. Clicking the “Pick Dates” 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.
Sun 4/269:19 pm
GEG
- ORD
1 stop30h 49m
Multiple Airlines
Deal found 2/28![Multiple Airlines logo]()
$101
This Kiwi.com deal was found by Cheapflights users on 3/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/410:21 pm
IDA
- ORD
1 stop31h 26m
Multiple Airlines
Deal found 3/3![Multiple Airlines logo]()
$104
This Kiwi.com deal was found by Cheapflights users on 3/2. Clicking the “Pick Dates” 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 3/242:22 pm
BOI
- ORD
1 stop8h 37m
Hawaiian Airlines
Deal found 3/2![Hawaiian Airlines logo]()
$105
This Trip.com deal was found by Cheapflights users on 3/2. Clicking the “Pick Dates” 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.
Tue 5/52:57 pm
BOI
- ORD
1 stop8h 02m
Alaska Airlines
Deal found 3/2![Alaska Airlines logo]()
$108
This Kiwi.com deal was found by Cheapflights users on 3/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/2710:21 pm
IDA
- ORD
1 stop30h 47m
Multiple Airlines
Deal found 3/1![Multiple Airlines logo]()
$108
This Trip.com deal was found by Cheapflights users on 3/1. Clicking the “Pick Dates” 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 4/157:43 pm
GEG
- ORD
1 stop8h 56m
Hawaiian Airlines
Deal found 3/1![Hawaiian Airlines logo]()
$110
This Kiwi.com deal was found by Cheapflights users on 3/3. Clicking the “Pick Dates” 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.
Sun 5/39:19 pm
GEG
- ORD
1 stop31h 28m
Multiple Airlines
Deal found 3/3![Multiple Airlines logo]()
$114
This Alaska Airlines deal was found by Cheapflights users on 3/2. Clicking the “Pick Dates” 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 3/308:28 pm
BOI
- ORD
1 stop9h 11m
Alaska Airlines
Deal found 3/2![Alaska Airlines logo]()
$115
This Priceline deal was found by Cheapflights users on 3/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/1411:53 am
BOI
- STL
1 stop6h 19m
Frontier
Deal found 3/5![Frontier logo]()
$116
This Alaska Airlines deal was found by Cheapflights users on 3/2. Clicking the “Pick Dates” 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 4/292:45 pm
GEG
- ORD
1 stop7h 14m
Alaska Airlines
Deal found 3/2![Alaska Airlines logo]()
$118
This Alaska Airlines deal was found by Cheapflights users on 3/2. Clicking the “Pick Dates” 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 4/166:04 pm
BOI
- ORD
1 stop11h 35m
Alaska Airlines
Deal found 3/2![Alaska Airlines logo]()
$120
This Alaska Airlines deal was found by Cheapflights users on 3/3. Clicking the “Pick Dates” 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 5/12:57 pm
BOI
- ORD
1 stop8h 02m
Alaska Airlines
Deal found 3/3![Alaska Airlines logo]()
$125
Find flight deals from Idaho to Illinois
Keep the following information in mind while searching for Idaho to Illinois flight deals. Data was last updated March 5, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $201 (CheapOair) |
One-way from | $101 (Kiwi.com) |
Popular in | March |
Cheapest in | September |
Average price | $403 |
Good round-trip deal | $340 or less |
Good one-way deal | $199 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Idaho to Illinois that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated March 5, 2026.
Use the filters below to find and compare flights from Idaho to Illinois that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
SpokaneChicago
GEG - MDW
GEGMDW
Spokane
Wed 4/15
2:25 pm-11:20 pm
1 stop6h 55m
Chicago Midway
Sat 4/18
6:00 am-10:05 am
1 stop6h 05m
$252
SpokaneChicago
GEG - ORD
GEGORD
Spokane
Wed 4/15
2:25 pm-11:55 pm
1 stop7h 30m
Chicago O'Hare Intl
Sat 4/18
4:15 pm-9:35 pm
1 stop7h 20m
$252
SpokaneChicago
GEG - ORD
GEGORD
Spokane
Tue 4/14
7:19 am-6:40 pm
1 stop9h 21m
Chicago O'Hare Intl
Wed 4/22
6:00 am-1:23 pm
1 stop9h 23m
$255
BoiseChicago
BOI - MDW
BOIMDW
Boise Air Term. Gowen Fld
Tue 3/31
5:30 am-5:54 pm
2 stops11h 24m
Chicago Midway
Tue 4/7
9:30 am-2:05 pm
1 stop5h 35m
$274
Idaho FallsChicago
IDA - ORD
IDAORD
Idaho Falls Fanning Field
Tue 3/31
6:55 pm-8:30 am
2 stops12h 35m
Chicago O'Hare Intl
Sun 4/5
7:20 am-12:27 pm
1 stop6h 07m
$274
BoiseChicago
BOI - MDW
BOIMDW
Boise Air Term. Gowen Fld
Wed 4/15
5:15 pm-5:25 am
1 stop11h 10m
Chicago Midway
Tue 4/21
5:35 pm-11:30 pm
1 stop6h 55m
$275
SpokaneChicago
GEG - MDW
GEGMDW
Spokane
Tue 5/5
7:00 am-5:05 pm
1 stop8h 05m
Chicago Midway
Wed 5/13
6:10 am-1:45 pm
1 stop9h 35m
$275
SpokaneSt. Louis
GEG - STL
GEGSTL
Spokane
Tue 4/21
6:00 am-5:21 pm
1 stop9h 21m
Lambert-St Louis
Tue 4/28
9:34 am-4:55 pm
1 stop9h 21m
$277
BoiseSt. Louis
BOI - STL
BOISTL
Boise Air Term. Gowen Fld
Tue 4/21
6:00 am-1:30 pm
1 stop6h 30m
Lambert-St Louis
Sat 4/25
6:05 am-2:10 pm
1 stop9h 05m
$277
BoiseChicago
BOI - ORD
BOIORD
Boise Air Term. Gowen Fld
Wed 5/6
10:41 am-9:18 pm
2 stops9h 37m
Chicago O'Hare Intl
Mon 7/13
3:50 pm-11:56 pm
2 stops9h 06m
$279
Showing 1-10 of 60 resultsSorted by cheapest first
Best time to book a flight from Idaho to Illinois
Have a flexible travel schedule? Discover the best time to fly to Illinois from Idaho with our price prediction graph.
GEG-ORD
IDA-ORD
BOI-ORD
BOI-STL
GEG-MDW
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.
Cheapflights Insights
Everything you need to know about your flight from Idaho to Illinois
USID-USIL
GEG-ORD
IDA-ORD
BOI-ORD
BOI-STL
What is the cheapest month to book a flight from Idaho to Illinois?
Currently, May is the cheapest month in which you can book a flight from Idaho to Illinois (average of $87). Flying from Idaho to Illinois in December is currently the most expensive (average of $276). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.
What is the cheapest time of day to fly from ID to IL?
Find hourly flight availability from Idaho to Illinois. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated March 5, 2026.
It’s optimal to fly from Idaho to Illinois in the afternoon. By choosing this option you can save up to 41% on the cost of your flight, compared to a flight in the evening.
Reviews of airlines servicing Illinois
Get insights into the airlines that provide service to Illinois. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Illinois. Reviews last updated March 5, 2026.
Read through reviews of airlines operating flights from Idaho to Illinois, such as Alaska Airlines, Southwest, and Delta. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Entertainment
7.0
Comfort
7.8
Overall
8.0
Crew
8.5
Food
7.1
Boarding
8.1
Reviews
1 / 20
10.0
Excellentrobert,Feb 2026
LAS - SAN
Entertainment
7.0
Comfort
7.8
Overall
8.0
Crew
8.5
Food
7.1
Boarding
8.1
Reviews
1 / 20
10.0
Excellentrobert,Feb 2026
LAS - SAN
Entertainment
7.0
Comfort
7.8
Overall
8.0
Crew
8.5
Food
7.1
Boarding
8.1
Reviews
1 / 20
10.0
Excellentrobert,Feb 2026
LAS - SAN
Entertainment
7.0
Comfort
7.8
Overall
8.0
Crew
8.5
Food
7.1
Boarding
8.1
Reviews
1 / 20
10.0
Excellentrobert,Feb 2026
LAS - SAN
Entertainment
7.0
Comfort
7.8
Overall
8.0
Crew
8.5
Food
7.1
Boarding
8.1
Reviews
1 / 20
10.0
Excellentrobert,Feb 2026
LAS - SAN
Entertainment
7.0
Comfort
7.8
Overall
8.0
Crew
8.5
Food
7.1
Boarding
8.1
Reviews
1 / 20
10.0
Excellentrobert,Feb 2026
LAS - SAN
Related info for your journey
Find useful and relevant information for your journey from Idaho to Illinois. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
Browse thousands of different options on Cheapflights for your next trip
Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.
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Alternative routes for Idaho to Illinois
See prices for flight routes from nearby airports that may be better suited for you.
Complete your trip
Complete your trip to Illinois by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Idaho to Illinois by cabin class
Find flights from Idaho to Illinois, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Idaho and Illinois flights
Browse other Idaho and Illinois flight options. Last updated on March 5, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Find a return flight route from Illinois
Find the right flight back to Idaho after your stay in Illinois
Idaho to Illinois flights
Consider these flights traveling from Idaho to Illinois.
Top 5 airlines flying from Idaho to Illinois
Discover the top 5 airlines that operate flights from Idaho to Illinois. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated March 5, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$87 | Average$280 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$219 | Average$520 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$224 | Average$358 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$233 | Average$378 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$255 | Average$440 | FlexibilityNo cancel fee | On-time71% |