$165+ Cheap flights from St. Louis (STL) to Idaho
This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 8/3. Fares are subject to change and may not be available on all flights or dates of travel.
STL — BOI
Jul 11 — Jul 181
Round-trip
1 adult, Economy
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Cheapest flights from St. Louis to IdahoExplore the most affordable flight options available from St. Louis to Idaho. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 11, 2026.
Explore the most affordable flight options available from St. Louis to Idaho. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 11, 2026.
This CheapOair deal was found by Cheapflights users on 6/7. Clicking the “Pick Dates” 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 7/158:08 pm
STL
- BOI
1 stop17h 21m
Frontier
Tue 7/211:24 pm
BOI
- STL
1 stop4h 59m
Frontier
Deal found 6/7![Frontier logo]()
$280
This Expedia deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” 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 8/207:36 pm
STL
- BOI
1 stop15h 16m
Multiple Airlines
Tue 8/251:04 pm
BOI
- STL
1 stop5h 19m
Multiple Airlines
Deal found 6/10![Multiple Airlines logo]()
$290
This Delta deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/246:55 pm
STL
- BOI
1 stop6h 03m
Delta
Tue 9/296:40 pm
BOI
- STL
1 stop4h 54m
Delta
Deal found 6/11![Delta logo]()
$291
This CheapOair deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” 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 7/47:38 pm
STL
- BOI
1 stop17h 51m
Frontier
Tue 7/71:24 pm
BOI
- STL
1 stop4h 59m
Frontier
Deal found 6/10![Frontier logo]()
$294
This American Airlines deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” 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.
Thu 8/205:42 am
STL
- BOI
1 stop6h 34m
American Airlines
Tue 8/258:01 am
BOI
- STL
2 stops11h 25m
American Airlines
Deal found 6/10![American Airlines logo]()
$296
This Delta deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/125:34 pm
STL
- GEG
1 stop7h 35m
Delta
Wed 8/195:00 pm
GEG
- STL
1 stop5h 41m
Delta
Deal found 6/9![Delta logo]()
$299
This Kiwi.com deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/42:56 pm
STL
- IDA
2 stops18h 59m
Multiple Airlines
Fri 7/1010:47 pm
IDA
- STL
1 stop18h 28m
Multiple Airlines
Deal found 6/11![Multiple Airlines logo]()
$317
This Alaska Airlines deal was found by Cheapflights users on 6/7. Clicking the “Pick Dates” 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 11/147:00 am
STL
- IDA
1 stop9h 17m
Alaska Airlines
Wed 11/186:04 am
IDA
- STL
1 stop7h 11m
Alaska Airlines
Deal found 6/7![Alaska Airlines logo]()
$319
This CheapOair deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/18:08 pm
STL
- BOI
1 stop17h 22m
Frontier
Thu 7/161:24 pm
BOI
- STL
1 stop4h 59m
Frontier
Deal found 6/11![Frontier logo]()
$319
This Booking.com deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 6/287:38 pm
STL
- GEG
1 stop17h 58m
Frontier
Wed 7/112:31 pm
GEG
- STL
1 stop28h 22m
Frontier
Deal found 6/9![Frontier logo]()
$323
This American Airlines deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/295:42 am
STL
- BOI
2 stops8h 42m
American Airlines
Sat 9/58:01 am
BOI
- STL
1 stop8h 36m
American Airlines
Deal found 6/10![American Airlines logo]()
$324
This American Airlines deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” 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.
Thu 9/247:27 am
STL
- BOI
1 stop8h 04m
American Airlines
Tue 9/291:52 pm
BOI
- STL
2 stops9h 35m
American Airlines
Deal found 6/9![American Airlines logo]()
$330
Best flights from St. Louis to IdahoDiscover carefully curated flight deals from St. Louis to Idaho that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated June 11, 2026.
Discover carefully curated flight deals from St. Louis to Idaho that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated June 11, 2026.
This Delta deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” 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 8/207:45 pm
STL
- GEG
1 stop6h 08m
Delta
Tue 8/255:00 pm
GEG
- STL
1 stop5h 41m
Delta
Deal found 6/9![Delta logo]()
$331
This Alaska Airlines deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” 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 9/16:08 pm
STL
- GEG
1 stop7h 03m
Alaska Airlines
Wed 9/25:52 am
GEG
- STL
1 stop6h 14m
Alaska Airlines
Deal found 6/8![Alaska Airlines logo]()
$331
This CheapOair deal was found by Cheapflights users on 6/7. Clicking the “Pick Dates” 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 6/248:08 pm
STL
- BOI
1 stop17h 22m
Frontier
Thu 7/301:24 pm
BOI
- STL
1 stop4h 59m
Frontier
Deal found 6/7![Frontier logo]()
$339
This United Airlines deal was found by Cheapflights users on 6/7. Clicking the “Pick Dates” 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 7/155:10 am
STL
- IDA
1 stop5h 40m
United Airlines
Wed 7/224:14 pm
IDA
- STL
1 stop6h 43m
United Airlines
Deal found 6/7![United Airlines logo]()
$365
This Southwest deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” 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 8/146:25 pm
STL
- BOI
1 stop6h 10m
Southwest
Mon 8/173:50 pm
BOI
- STL
1 stop7h 45m
Southwest
Deal found 6/8![Southwest logo]()
$394
This Delta deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” 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 7/297:55 pm
STL
- GEG
1 stop6h 00m
Delta
Wed 8/126:45 am
GEG
- STL
1 stop7h 59m
Delta
Deal found 6/10![Delta logo]()
$341
This Alaska Airlines deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” 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 8/256:35 am
STL
- BOI
1 stop8h 47m
Alaska Airlines
Wed 8/266:23 am
BOI
- STL
1 stop6h 43m
Alaska Airlines
Deal found 6/10![Alaska Airlines logo]()
$362
This United Airlines deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” 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 7/411:25 am
STL
- BOI
2 stops11h 04m
United Airlines
Tue 7/75:46 pm
BOI
- STL
1 stop5h 11m
United Airlines
Deal found 6/10![United Airlines logo]()
$408
This Delta deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” 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 9/162:27 pm
STL
- JAC
1 stop5h 54m
Delta
Mon 9/215:54 pm
JAC
- STL
1 stop5h 40m
Delta
Deal found 6/9![Delta logo]()
$389
This Southwest deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” 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 7/233:20 pm
STL
- GEG
2 stops11h 15m
Southwest
Tue 7/2810:20 am
GEG
- STL
2 stops11h 15m
Southwest
Deal found 6/8![Southwest logo]()
$452
This United Airlines deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/111:38 pm
STL
- JAC
1 stop5h 15m
United Airlines
Fri 7/178:00 am
JAC
- STL
1 stop9h 17m
United Airlines
Deal found 6/11![United Airlines logo]()
$415
This Alaska Airlines deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” 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 8/116:02 am
STL
- GEG
1 stop8h 27m
Alaska Airlines
Wed 8/125:07 am
GEG
- STL
1 stop6h 45m
Alaska Airlines
Deal found 6/9![Alaska Airlines logo]()
$425
This Delta deal was found by Cheapflights users on 6/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/192:32 pm
STL
- JAC
1 stop5h 23m
Delta
Mon 8/246:01 pm
JAC
- STL
1 stop5h 40m
Delta
Deal found 6/7![Delta logo]()
$399
This Southwest deal was found by Cheapflights users on 6/7. Clicking the “Pick Dates” 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 8/285:55 am
STL
- GEG
1 stop7h 45m
Southwest
Tue 9/11:55 pm
GEG
- STL
1 stop5h 15m
Southwest
Deal found 6/7![Southwest logo]()
$467
This United Airlines deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/251:36 pm
STL
- BOI
2 stops8h 48m
United Airlines
Wed 8/2612:24 pm
BOI
- STL
1 stop8h 36m
United Airlines
Deal found 6/10![United Airlines logo]()
$430
This Alaska Airlines deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/27:56 pm
STL
- GEG
1 stop14h 30m
Alaska Airlines
Thu 8/135:00 am
GEG
- STL
1 stop9h 37m
Alaska Airlines
Deal found 6/11![Alaska Airlines logo]()
$443
This Delta deal was found by Cheapflights users on 6/6. Clicking the “Pick Dates” 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 6/306:21 am
STL
- BOI
1 stop5h 37m
Delta
Tue 7/76:42 pm
BOI
- STL
1 stop4h 59m
Delta
Deal found 6/6![Delta logo]()
$405
This Southwest deal was found by Cheapflights users on 6/6. Clicking the “Pick Dates” 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 9/116:25 pm
STL
- BOI
1 stop6h 10m
Southwest
Mon 9/1412:10 pm
BOI
- STL
1 stop5h 55m
Southwest
Deal found 6/6![Southwest logo]()
$467
This United Airlines deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/115:10 am
STL
- JAC
1 stop5h 36m
United Airlines
Tue 7/144:23 pm
JAC
- STL
1 stop6h 34m
United Airlines
Deal found 6/9![United Airlines logo]()
$436
This Delta deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” 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 7/16:21 am
STL
- GEG
1 stop7h 19m
Delta
Sat 7/47:00 am
GEG
- STL
1 stop7h 46m
Delta
Deal found 6/8![Delta logo]()
$411
This Southwest deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/207:45 pm
STL
- BOI
1 stop6h 30m
Southwest
Sat 7/256:00 pm
BOI
- STL
1 stop6h 05m
Southwest
Deal found 6/9![Southwest logo]()
$467
This Alaska Airlines deal was found by Cheapflights users on 6/7. Clicking the “Pick Dates” 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 7/35:37 pm
STL
- IDA
1 stop20h 29m
Alaska Airlines
Thu 7/97:15 am
IDA
- STL
1 stop10h 42m
Alaska Airlines
Deal found 6/7![Alaska Airlines logo]()
$474
This Delta deal was found by Cheapflights users on 6/7. Clicking the “Pick Dates” 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 7/1511:18 am
STL
- IDA
2 stops8h 00m
Delta
Wed 7/227:00 pm
IDA
- STL
1 stop4h 41m
Delta
Deal found 6/7![Delta logo]()
$452
This United Airlines deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/15:10 am
STL
- JAC
1 stop5h 24m
United Airlines
Sat 7/118:00 am
JAC
- STL
1 stop9h 17m
United Airlines
Deal found 6/11![United Airlines logo]()
$501
This United Airlines deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” 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 11/214:30 pm
STL
- JAC
1 stop5h 32m
United Airlines
Fri 11/272:40 pm
JAC
- STL
2 stops8h 54m
United Airlines
Deal found 6/9![United Airlines logo]()
$506
This Alaska Airlines deal was found by Cheapflights users on 6/7. Clicking the “Pick Dates” 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 7/315:37 pm
STL
- IDA
1 stop20h 29m
Alaska Airlines
Sun 8/24:14 pm
IDA
- STL
1 stop23h 23m
Alaska Airlines
Deal found 6/7![Alaska Airlines logo]()
$589
This United Airlines deal was found by Cheapflights users on 6/6. Clicking the “Pick Dates” 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 11/174:30 pm
STL
- JAC
1 stop5h 32m
United Airlines
Wed 11/182:40 pm
JAC
- STL
1 stop5h 19m
United Airlines
Deal found 6/6![United Airlines logo]()
$509
This Delta deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” 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 8/102:32 pm
STL
- LWS
2 stops10h 27m
Delta
Mon 8/1712:23 pm
LWS
- STL
2 stops9h 03m
Delta
Deal found 6/9![Delta logo]()
$527
This United Airlines deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/169:13 am
STL
- JAC
1 stop6h 59m
United Airlines
Wed 11/187:00 am
JAC
- STL
1 stop4h 43m
United Airlines
Deal found 6/9![United Airlines logo]()
$509
This United Airlines deal was found by Cheapflights users on 6/7. Clicking the “Pick Dates” 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 7/155:10 am
STL
- JAC
2 stops9h 38m
United Airlines
Tue 7/214:23 pm
JAC
- STL
1 stop6h 34m
United Airlines
Deal found 6/7![United Airlines logo]()
$515
Last-minute flights from St. Louis to IdahoDiscover last-minute flight deals from St. Louis to Idaho. Data last updated June 11, 2026 and is based on user searches.
Discover last-minute flight deals from St. Louis to Idaho. Data last updated June 11, 2026 and is based on user searches.
This Delta deal was found by Cheapflights users on 6/7. Clicking the “Pick Dates” 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 6/232:28 pm
STL
- JAC
1 stop6h 14m
Delta
Mon 6/296:05 pm
JAC
- STL
1 stop5h 38m
Delta
Deal found 6/7![Delta logo]()
$359
This CheapOair deal was found by Cheapflights users on 6/7. Clicking the “Pick Dates” 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 6/248:08 pm
STL
- BOI
1 stop17h 22m
Frontier
Thu 7/301:24 pm
BOI
- STL
1 stop4h 59m
Frontier
Deal found 6/7![Frontier logo]()
$339
This Booking.com deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 6/287:38 pm
STL
- GEG
1 stop17h 58m
Frontier
Wed 7/112:31 pm
GEG
- STL
1 stop28h 22m
Frontier
Deal found 6/9![Frontier logo]()
$323
This CheapOair deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/18:08 pm
STL
- BOI
1 stop17h 22m
Frontier
Thu 7/161:24 pm
BOI
- STL
1 stop4h 59m
Frontier
Deal found 6/11![Frontier logo]()
$319
This Expedia deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/37:56 pm
STL
- BOI
1 stop14h 44m
Multiple Airlines
Tue 7/71:24 pm
BOI
- STL
1 stop4h 59m
Multiple Airlines
Deal found 6/9![Multiple Airlines logo]()
$342
This CheapOair deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” 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 7/47:38 pm
STL
- BOI
1 stop17h 51m
Frontier
Tue 7/71:24 pm
BOI
- STL
1 stop4h 59m
Frontier
Deal found 6/10![Frontier logo]()
$294
This Kiwi.com deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/42:56 pm
STL
- IDA
2 stops18h 59m
Multiple Airlines
Fri 7/1010:47 pm
IDA
- STL
1 stop18h 28m
Multiple Airlines
Deal found 6/11![Multiple Airlines logo]()
$317
This United Airlines deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/49:11 am
STL
- IDA
1 stop5h 14m
United Airlines
Fri 7/105:54 pm
IDA
- STL
1 stop5h 03m
United Airlines
Deal found 6/11![United Airlines logo]()
$361
This Booking.com deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/88:08 pm
STL
- BOI
1 stop17h 21m
Multiple Airlines
Wed 7/154:27 pm
BOI
- STL
1 stop6h 32m
Multiple Airlines
Deal found 6/10![Multiple Airlines logo]()
$351
This CheapOair deal was found by Cheapflights users on 6/7. Clicking the “Pick Dates” 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 7/158:08 pm
STL
- BOI
1 stop17h 21m
Frontier
Tue 7/211:24 pm
BOI
- STL
1 stop4h 59m
Frontier
Deal found 6/7![Frontier logo]()
$280
This United Airlines deal was found by Cheapflights users on 6/7. Clicking the “Pick Dates” 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 7/155:10 am
STL
- IDA
1 stop5h 40m
United Airlines
Wed 7/224:14 pm
IDA
- STL
1 stop6h 43m
United Airlines
Deal found 6/7![United Airlines logo]()
$365
This Delta deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” 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 7/297:55 pm
STL
- GEG
1 stop6h 00m
Delta
Wed 8/126:45 am
GEG
- STL
1 stop7h 59m
Delta
Deal found 6/9![Delta logo]()
$341
One-way flights from St. Louis to IdahoSearch for one-way flight options from St. Louis to Idaho. Find affordable one-way fares based on user searches. Data last updated June 11, 2026.
Search for one-way flight options from St. Louis to Idaho. Find affordable one-way fares based on user searches. Data last updated June 11, 2026.
This CheapOair deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/38:08 pm
STL
- BOI
1 stop17h 21m
Frontier
Deal found 6/11![Frontier logo]()
$165
This CheapOair deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/18:08 pm
STL
- BOI
1 stop17h 22m
Frontier
Deal found 6/11![Frontier logo]()
$166
This Kiwi.com deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” 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 7/88:08 pm
STL
- BOI
1 stop17h 21m
Frontier
Deal found 6/8![Frontier logo]()
$184
This Alaska Airlines deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/266:29 am
STL
- JAC
1 stop29h 53m
Alaska Airlines
Deal found 6/11![Alaska Airlines logo]()
$185
This United Airlines deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/205:10 am
STL
- IDA
1 stop5h 40m
United Airlines
Deal found 6/9![United Airlines logo]()
$192
This Delta deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” 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 7/77:55 pm
STL
- BOI
1 stop5h 10m
Delta
Deal found 6/10![Delta logo]()
$202
This American Airlines deal was found by Cheapflights users on 6/7. Clicking the “Pick Dates” 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 7/75:32 am
STL
- BOI
1 stop6h 47m
American Airlines
Deal found 6/7![American Airlines logo]()
$204
This American Airlines deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 7/125:32 am
STL
- JAC
1 stop5h 42m
American Airlines
Deal found 6/11![American Airlines logo]()
$210
This Kiwi.com deal was found by Cheapflights users on 6/7. Clicking the “Pick Dates” 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 8/167:10 pm
STL
- IDA
1 stop21h 55m
Multiple Airlines
Deal found 6/7![Multiple Airlines logo]()
$212
This American Airlines deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” 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 11/66:00 am
STL
- GEG
1 stop8h 32m
American Airlines
Deal found 6/9![American Airlines logo]()
$213
This Kiwi.com deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/274:57 pm
STL
- BOI
2 stops20h 32m
Frontier
Deal found 6/11![Frontier logo]()
$213
This United Airlines deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/235:10 am
STL
- IDA
1 stop5h 40m
United Airlines
Deal found 6/11![United Airlines logo]()
$230
Find flight deals from St. Louis to Idaho
Keep the following information in mind while searching for St. Louis to Idaho flight deals. Data was last updated June 11, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $280 (CheapOair) |
One-way from | $165 (CheapOair) |
Popular in | February |
Cheapest in | January |
Average price | $503 |
Cheapflights Fare Finder
Customize your flight search to find flights from St. Louis 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 June 11, 2026.
Use the filters below to find and compare flights from St. Louis to Idaho that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
St. LouisSpokane
STL - GEG
STLGEG
Lambert-St Louis
Thu 8/20
7:45 pm-11:53 pm
1 stop6h 08m
Spokane
Tue 8/25
5:00 pm-12:41 am
1 stop5h 41m
$331
St. LouisSpokane
STL - GEG
STLGEG
Lambert-St Louis
Tue 9/1
6:08 pm-11:11 pm
1 stop7h 03m
Spokane
Wed 9/2
5:52 am-2:06 pm
1 stop6h 14m
$331
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Wed 6/24
8:08 pm-12:30 pm
1 stop17h 22m
Boise Air Term. Gowen Fld
Thu 7/30
1:24 pm-7:23 pm
1 stop4h 59m
$339
St. LouisSpokane
STL - GEG
STLGEG
Lambert-St Louis
Wed 7/29
7:55 pm-11:55 pm
1 stop6h 00m
Spokane
Wed 8/12
6:45 am-4:44 pm
1 stop7h 59m
$341
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Tue 8/25
6:35 am-2:22 pm
1 stop8h 47m
Boise Air Term. Gowen Fld
Wed 8/26
6:23 am-2:06 pm
1 stop6h 43m
$362
St. LouisIdaho Falls
STL - IDA
STLIDA
Lambert-St Louis
Wed 7/15
5:10 am-9:50 am
1 stop5h 40m
Idaho Falls Fanning Field
Wed 7/22
4:14 pm-11:57 pm
1 stop6h 43m
$365
St. LouisJackson
STL - JAC
STLJAC
Lambert-St Louis
Wed 9/16
2:27 pm-7:21 pm
1 stop5h 54m
Jackson Hole
Mon 9/21
5:54 pm-12:34 am
1 stop5h 40m
$389
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Fri 8/14
6:25 pm-11:35 pm
1 stop6h 10m
Boise Air Term. Gowen Fld
Mon 8/17
3:50 pm-12:35 am
1 stop7h 45m
$394
St. LouisJackson
STL - JAC
STLJAC
Lambert-St Louis
Wed 8/19
2:32 pm-6:55 pm
1 stop5h 23m
Jackson Hole
Mon 8/24
6:01 pm-12:41 am
1 stop5h 40m
$399
Quickest round-trip
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Tue 6/30
6:21 am-10:58 am
1 stop5h 37m
Boise Air Term. Gowen Fld
Tue 7/7
6:42 pm-12:41 am
1 stop4h 59m
$405
Showing 1-10 of 60 resultsSorted by cheapest first
Best time to book a flight from St. Louis to Idaho
Have a flexible travel schedule? Discover the best time to fly to Idaho from St. Louis with our price prediction graph.
STL-BOI
STL-JAC
STL-IDA
STL-GEG
STL-LWS
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 St. Louis to Idaho
STL-USID
STL-BOI
STL-JAC
STL-IDA
STL-GEG
What is the cheapest month to book a flight from St. Louis to Idaho?
Currently, September is the cheapest month in which you can book a flight from St. Louis to Idaho (average of $186). Flying from St. Louis to Idaho in February is currently the most expensive (average of $553). 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.
How much does it cost to fly round-trip from St. Louis 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 June 11, 2026.
Peruse reviews from past customers who have flown with Southwest,Delta, andUnited Airlines from St. Louis to Idaho to help guide your decision. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Entertainment
7.5
Boarding
8.1
Crew
8.6
Food
7.0
Overall
7.9
Comfort
8.0
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Entertainment
7.5
Boarding
8.1
Crew
8.6
Food
7.0
Overall
7.9
Comfort
8.0
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Entertainment
7.5
Boarding
8.1
Crew
8.6
Food
7.0
Overall
7.9
Comfort
8.0
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Entertainment
7.5
Boarding
8.1
Crew
8.6
Food
7.0
Overall
7.9
Comfort
8.0
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Entertainment
7.5
Boarding
8.1
Crew
8.6
Food
7.0
Overall
7.9
Comfort
8.0
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Related info for your journey
Find useful and relevant information for your journey from St. Louis to Idaho. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
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Alternative routes for St. Louis 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.
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Find flights from St. Louis to Idaho, based on your preferred cabin class, be it economy, premium economy, business, or first class.
St. Louis and Idaho flights
Browse other St. Louis and Idaho flight options. Last updated on June 11, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
St. Louis to Idaho flights
Consider these flights traveling from St. Louis to Idaho.
Top 4 airlines flying from St. Louis to Idaho
Discover the top 4 airlines that operate flights from St. Louis 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 June 11, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$186 | Average$391 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$240 | Average$396 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$290 | Average$519 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$296 | Average$462 | FlexibilityNo cancel fee | On-time63% |