$159+ 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 4/25. Fares are subject to change and may not be available on all flights or dates of travel.
STL — BOI
May 2 — May 91
Round-trip
1 adult, Economy
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Find cheap flights from St. Louis to Idaho with Cheapflights
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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
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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 April 2, 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 April 2, 2026.
This CheapOair deal was found by Cheapflights users on 3/29. Clicking the “Pick Dates” 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 01m
Frontier
Tue 6/301:04 pm
BOI
- STL
1 stop5h 19m
Frontier
Deal found 3/29![Frontier logo]()
$241
This Alaska Airlines deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 5/27:00 am
STL
- BOI
1 stop9h 33m
Alaska Airlines
Tue 5/52:57 pm
BOI
- STL
1 stop8h 02m
Alaska Airlines
Deal found 3/30![Alaska Airlines logo]()
$317
This Delta deal was found by Cheapflights users on 3/29. Clicking the “Pick Dates” 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 8/247:30 am
STL
- WYS
1 stop5h 51m
Delta
Sat 8/2911:29 am
WYS
- STL
2 stops11h 08m
Delta
Deal found 3/29![Delta logo]()
$334
This American Airlines deal was found by Cheapflights users on 4/1. 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.
Wed 5/67:05 am
STL
- GEG
1 stop7h 27m
American Airlines
Wed 5/131:13 pm
GEG
- STL
1 stop8h 43m
American Airlines
Deal found 4/1![American Airlines logo]()
$347
This Expedia deal was found by Cheapflights users on 4/1. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/304:46 pm
STL
- GEG
1 stop9h 09m
Multiple Airlines
Sun 5/311:44 am
GEG
- STL
1 stop5h 37m
Multiple Airlines
Deal found 4/1![Multiple Airlines logo]()
$348
This American Airlines deal was found by Cheapflights users on 4/2. 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.
Sat 5/25:51 am
STL
- GEG
1 stop8h 41m
American Airlines
Sat 5/306:30 am
GEG
- STL
1 stop9h 04m
American Airlines
Deal found 4/2![American Airlines logo]()
$352
This Delta deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/146:45 pm
STL
- IDA
1 stop4h 55m
Delta
Sat 4/186:58 pm
IDA
- STL
2 stops12h 32m
Delta
Deal found 3/30![Delta logo]()
$354
This United Airlines deal was found by Cheapflights users on 4/2. 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.
Sat 5/26:30 am
STL
- GEG
2 stops10h 48m
United Airlines
Sat 5/301:41 pm
GEG
- STL
1 stop5h 16m
United Airlines
Deal found 4/2![United Airlines logo]()
$357
This American Airlines deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 4/247:12 am
STL
- JAC
1 stop6h 29m
American Airlines
Mon 4/271:25 pm
JAC
- STL
1 stop8h 34m
American Airlines
Deal found 3/30![American Airlines logo]()
$359
This American Airlines deal was found by Cheapflights users on 3/28. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/305:51 am
STL
- GEG
1 stop8h 41m
American Airlines
Sat 5/21:22 pm
GEG
- STL
1 stop6h 55m
American Airlines
Deal found 3/28![American Airlines logo]()
$361
This Delta deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 4/276:45 pm
STL
- BOI
1 stop6h 12m
Delta
Wed 5/62:18 pm
BOI
- STL
1 stop8h 17m
Delta
Deal found 3/30![Delta logo]()
$361
This United Airlines deal was found by Cheapflights users on 4/2. 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.
Sat 5/29:00 am
STL
- JAC
2 stops12h 58m
United Airlines
Sat 5/97:00 am
JAC
- STL
1 stop6h 28m
United Airlines
Deal found 4/2![United Airlines logo]()
$364
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 April 2, 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 April 2, 2026.
This Alaska Airlines deal was found by Cheapflights users on 3/28. 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.
Sat 5/27:00 am
STL
- BOI
1 stop9h 33m
Alaska Airlines
Tue 5/52:57 pm
BOI
- STL
1 stop8h 02m
Alaska Airlines
Deal found 3/28![Alaska Airlines logo]()
$317
This Delta deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/146:45 pm
STL
- IDA
1 stop4h 55m
Delta
Sat 4/186:58 pm
IDA
- STL
2 stops12h 32m
Delta
Deal found 3/30![Delta logo]()
$354
This United Airlines deal was found by Cheapflights users on 4/2. 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.
Sat 5/26:30 am
STL
- GEG
2 stops10h 48m
United Airlines
Sat 5/301:41 pm
GEG
- STL
1 stop5h 16m
United Airlines
Deal found 4/2![United Airlines logo]()
$357
This Southwest deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/66:35 am
STL
- GEG
2 stops9h 10m
Southwest
Fri 5/85:50 am
GEG
- STL
2 stops8h 00m
Southwest
Deal found 3/30![Southwest logo]()
$397
This American Airlines deal was found by Cheapflights users on 3/31. Clicking the “Pick Dates” 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 6/65:25 am
STL
- IDA
1 stop7h 49m
American Airlines
Tue 6/912:44 pm
IDA
- STL
1 stop10h 10m
American Airlines
Deal found 3/31![American Airlines logo]()
$447
This Kiwi.com deal was found by Cheapflights users on 4/1. 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.
Thu 4/169:55 pm
STL
- IDA
1 stop18h 32m
Multiple Airlines
Mon 4/2010:21 pm
IDA
- STL
2 stops31h 29m
Multiple Airlines
Deal found 4/1![Multiple Airlines logo]()
$496
This Delta deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 4/276:45 pm
STL
- BOI
1 stop6h 12m
Delta
Wed 5/62:18 pm
BOI
- STL
1 stop8h 17m
Delta
Deal found 3/30![Delta logo]()
$361
This United Airlines deal was found by Cheapflights users on 3/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/210:25 am
STL
- BOI
2 stops11h 52m
United Airlines
Tue 5/52:26 pm
BOI
- STL
1 stop5h 17m
United Airlines
Deal found 3/29![United Airlines logo]()
$412
This Southwest deal was found by Cheapflights users on 4/2. 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.
Sat 5/28:45 am
STL
- GEG
2 stops9h 20m
Southwest
Sat 5/306:15 am
GEG
- STL
2 stops9h 55m
Southwest
Deal found 4/2![Southwest logo]()
$425
This Delta deal was found by Cheapflights users on 3/29. Clicking the “Pick Dates” 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 5/205:36 pm
STL
- BOI
1 stop7h 10m
Delta
Thu 5/286:41 pm
BOI
- STL
1 stop4h 49m
Delta
Deal found 3/29![Delta logo]()
$405
This United Airlines deal was found by Cheapflights users on 3/28. 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.
Wed 5/275:10 am
STL
- IDA
1 stop5h 40m
United Airlines
Thu 6/114:10 pm
IDA
- STL
1 stop6h 47m
United Airlines
Deal found 3/28![United Airlines logo]()
$414
This Alaska Airlines deal was found by Cheapflights users on 3/31. Clicking the “Pick Dates” 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 5/97:00 am
STL
- GEG
2 stops13h 55m
Alaska Airlines
Wed 5/1312:46 pm
GEG
- STL
1 stop9h 08m
Alaska Airlines
Deal found 3/31![Alaska Airlines logo]()
$469
This United Airlines deal was found by Cheapflights users on 4/1. 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.
Tue 4/284:30 pm
STL
- BOI
1 stop5h 52m
United Airlines
Wed 4/292:37 pm
BOI
- STL
1 stop5h 17m
United Airlines
Deal found 4/1![United Airlines logo]()
$417
This Southwest deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 5/187:20 pm
STL
- GEG
1 stop7h 15m
Southwest
Thu 5/215:50 am
GEG
- STL
2 stops10h 30m
Southwest
Deal found 3/30![Southwest logo]()
$462
This Delta deal was found by Cheapflights users on 4/1. 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.
Thu 6/46:21 am
STL
- BOI
1 stop7h 57m
Delta
Sun 6/77:53 pm
BOI
- STL
2 stops11h 49m
Delta
Deal found 4/1![Delta logo]()
$425
This Alaska Airlines deal was found by Cheapflights users on 3/28. 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.
Thu 4/304:46 pm
STL
- GEG
2 stops17h 54m
Alaska Airlines
Sat 5/22:45 pm
GEG
- STL
1 stop7h 14m
Alaska Airlines
Deal found 3/28![Alaska Airlines logo]()
$471
This Southwest deal was found by Cheapflights users on 3/31. Clicking the “Pick Dates” 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 6/15:15 pm
STL
- GEG
2 stops9h 20m
Southwest
Mon 6/82:15 pm
GEG
- STL
2 stops7h 50m
Southwest
Deal found 3/31![Southwest logo]()
$467
This Delta deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/76:00 am
STL
- IDA
2 stops9h 34m
Delta
Sun 5/106:00 am
IDA
- STL
1 stop6h 32m
Delta
Deal found 3/30![Delta logo]()
$434
This Alaska Airlines deal was found by Cheapflights users on 3/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 6/65:33 pm
STL
- IDA
1 stop20h 44m
Alaska Airlines
Tue 6/94:03 pm
IDA
- STL
2 stops30h 53m
Alaska Airlines
Deal found 3/31![Alaska Airlines logo]()
$501
This United Airlines deal was found by Cheapflights users on 3/28. 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.
Sat 6/65:10 am
STL
- IDA
1 stop5h 40m
United Airlines
Tue 6/95:54 pm
IDA
- STL
1 stop5h 03m
United Airlines
Deal found 3/28![United Airlines logo]()
$465
This Delta deal was found by Cheapflights users on 3/31. Clicking the “Pick Dates” 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.
Sun 6/288:00 am
STL
- GEG
1 stop6h 15m
Delta
Fri 7/1010:48 pm
GEG
- STL
1 stop8h 18m
Delta
Deal found 3/31![Delta logo]()
$462
This United Airlines deal was found by Cheapflights users on 3/28. 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.
Sat 5/24:15 pm
STL
- IDA
1 stop5h 48m
United Airlines
Mon 5/42:31 pm
IDA
- STL
1 stop5h 12m
United Airlines
Deal found 3/28![United Airlines logo]()
$469
This Expedia deal was found by Cheapflights users on 3/28. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/287:41 pm
STL
- IDA
1 stop20h 45m
Alaska Airlines
Thu 6/114:14 pm
IDA
- STL
1 stop23h 19m
Alaska Airlines
Deal found 3/28![Alaska Airlines logo]()
$534
This United Airlines deal was found by Cheapflights users on 4/1. 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.
Mon 5/185:59 pm
STL
- WYS
1 stop20h 29m
United Airlines
Sun 5/245:45 pm
WYS
- STL
1 stop5h 12m
United Airlines
Deal found 4/1![United Airlines logo]()
$483
This Delta deal was found by Cheapflights users on 3/29. Clicking the “Pick Dates” 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 5/153:11 pm
STL
- JAC
1 stop6h 04m
Delta
Thu 5/215:59 pm
JAC
- STL
1 stop5h 31m
Delta
Deal found 3/29![Delta logo]()
$505
This United Airlines deal was found by Cheapflights users on 3/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/910:25 am
STL
- GEG
2 stops12h 51m
United Airlines
Wed 5/135:00 am
GEG
- STL
1 stop6h 13m
United Airlines
Deal found 3/29![United Airlines logo]()
$501
This Delta deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 8/107:30 am
STL
- LWS
1 stop6h 12m
Delta
Mon 8/1712:30 pm
LWS
- STL
2 stops8h 31m
Delta
Deal found 3/30![Delta logo]()
$522
This United Airlines deal was found by Cheapflights users on 4/2. 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.
Sat 5/231:38 pm
STL
- JAC
1 stop5h 16m
United Airlines
Sun 5/314:23 pm
JAC
- STL
1 stop6h 34m
United Airlines
Deal found 4/2![United Airlines logo]()
$507
This Delta deal was found by Cheapflights users on 3/29. Clicking the “Pick Dates” 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 8/48:00 am
STL
- WYS
1 stop5h 27m
Delta
Sat 8/811:29 am
WYS
- STL
2 stops11h 11m
Delta
Deal found 3/29![Delta logo]()
$534
This United Airlines deal was found by Cheapflights users on 4/1. 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.
Sat 5/234:45 pm
STL
- WYS
1 stop24h 17m
United Airlines
Sun 5/315:45 pm
WYS
- STL
1 stop5h 12m
United Airlines
Deal found 4/1![United Airlines logo]()
$547
Last-minute flights from St. Louis to IdahoDiscover last-minute flight deals from St. Louis to Idaho. Data last updated April 2, 2026 and is based on user searches.
Discover last-minute flight deals from St. Louis to Idaho. Data last updated April 2, 2026 and is based on user searches.
This Delta deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/146:45 pm
STL
- IDA
1 stop4h 55m
Delta
Sat 4/186:58 pm
IDA
- STL
2 stops12h 32m
Delta
Deal found 3/30![Delta logo]()
$354
This American Airlines deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 4/247:12 am
STL
- JAC
1 stop6h 29m
American Airlines
Mon 4/271:25 pm
JAC
- STL
1 stop8h 34m
American Airlines
Deal found 3/30![American Airlines logo]()
$359
This Delta deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 4/276:45 pm
STL
- BOI
1 stop6h 12m
Delta
Wed 5/62:18 pm
BOI
- STL
1 stop8h 17m
Delta
Deal found 3/30![Delta logo]()
$361
This Southwest deal was found by Cheapflights users on 3/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/275:15 pm
STL
- BOI
2 stops8h 30m
Southwest
Wed 5/64:05 pm
BOI
- STL
1 stop6h 10m
Southwest
Deal found 3/29![Southwest logo]()
$366
This Expedia deal was found by Cheapflights users on 4/1. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/304:46 pm
STL
- GEG
1 stop9h 09m
Multiple Airlines
Sun 5/311:44 am
GEG
- STL
1 stop5h 37m
Multiple Airlines
Deal found 4/1![Multiple Airlines logo]()
$348
This American Airlines deal was found by Cheapflights users on 3/28. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/305:51 am
STL
- GEG
1 stop8h 41m
American Airlines
Sat 5/21:22 pm
GEG
- STL
1 stop6h 55m
American Airlines
Deal found 3/28![American Airlines logo]()
$361
This Alaska Airlines deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 5/27:00 am
STL
- BOI
1 stop9h 33m
Alaska Airlines
Tue 5/52:57 pm
BOI
- STL
1 stop8h 02m
Alaska Airlines
Deal found 3/30![Alaska Airlines logo]()
$317
This American Airlines deal was found by Cheapflights users on 4/2. 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.
Sat 5/25:51 am
STL
- GEG
1 stop8h 41m
American Airlines
Sat 5/306:30 am
GEG
- STL
1 stop9h 04m
American Airlines
Deal found 4/2![American Airlines logo]()
$352
This United Airlines deal was found by Cheapflights users on 4/2. 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.
Sat 5/26:30 am
STL
- GEG
2 stops10h 48m
United Airlines
Sat 5/301:41 pm
GEG
- STL
1 stop5h 16m
United Airlines
Deal found 4/2![United Airlines logo]()
$357
This United Airlines deal was found by Cheapflights users on 4/2. 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.
Sat 5/29:00 am
STL
- JAC
2 stops12h 58m
United Airlines
Sat 5/97:00 am
JAC
- STL
1 stop6h 28m
United Airlines
Deal found 4/2![United Airlines logo]()
$364
This American Airlines deal was found by Cheapflights users on 4/1. 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.
Wed 5/67:05 am
STL
- GEG
1 stop7h 27m
American Airlines
Wed 5/131:13 pm
GEG
- STL
1 stop8h 43m
American Airlines
Deal found 4/1![American Airlines logo]()
$347
This Delta deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 5/256:45 am
STL
- JAC
2 stops11h 14m
Delta
Tue 6/21:15 pm
JAC
- STL
2 stops9h 06m
Delta
Deal found 3/30![Delta logo]()
$369
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 April 2, 2026.
Search for one-way flight options from St. Louis to Idaho. Find affordable one-way fares based on user searches. Data last updated April 2, 2026.
This American Airlines deal was found by Cheapflights users on 3/28. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/255:51 am
STL
- GEG
1 stop8h 41m
American Airlines
Deal found 3/28![American Airlines logo]()
$159
This United Airlines deal was found by Cheapflights users on 3/28. 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.
Sat 4/257:45 am
STL
- GEG
2 stops9h 30m
United Airlines
Deal found 3/28![United Airlines logo]()
$164
This CheapOair deal was found by Cheapflights users on 3/28. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/118:16 pm
STL
- BOI
1 stop15h 52m
Frontier
Deal found 3/28![Frontier logo]()
$167
This United Airlines deal was found by Cheapflights users on 3/31. Clicking the “Pick Dates” 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 6/35:10 am
STL
- IDA
1 stop5h 40m
United Airlines
Deal found 3/31![United Airlines logo]()
$170
This American Airlines deal was found by Cheapflights users on 3/31. Clicking the “Pick Dates” 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.
Wed 5/135:51 am
STL
- GEG
1 stop8h 32m
American Airlines
Deal found 3/31![American Airlines logo]()
$174
This Southwest deal was found by Cheapflights users on 3/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/136:35 am
STL
- GEG
2 stops9h 10m
Southwest
Deal found 3/31![Southwest logo]()
$179
This Kiwi.com deal was found by Cheapflights users on 4/1. 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.
Sat 5/167:08 pm
STL
- GEG
2 stops27h 21m
Multiple Airlines
Deal found 4/1![Multiple Airlines logo]()
$182
This Kiwi.com deal was found by Cheapflights users on 3/28. 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 5/1712:16 pm
STL
- GEG
1 stop10h 13m
Multiple Airlines
Deal found 3/28![Multiple Airlines logo]()
$193
This deal was found by Cheapflights users on 4/1. 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 is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/195:33 pm
STL
- GEG
1 stop7h 33m
Alaska Airlines
Deal found 4/1![Alaska Airlines logo]()
$194
This Kiwi.com deal was found by Cheapflights users on 4/1. 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.
Thu 4/168:06 pm
STL
- IDA
2 stops20h 21m
Multiple Airlines
Deal found 4/1![Multiple Airlines logo]()
$199
This Expedia deal was found by Cheapflights users on 4/1. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/165:33 pm
STL
- GEG
1 stop16h 55m
Alaska Airlines
Deal found 4/1![Alaska Airlines logo]()
$199
This Kiwi.com deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/144:59 pm
STL
- BOI
2 stops43h 09m
Frontier
Deal found 3/30![Frontier logo]()
$225
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 April 2, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $241 (CheapOair) |
One-way from | $159 (American Airlines) |
Popular in | February |
Cheapest in | January |
Average price | $396 |
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 April 2, 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. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Sat 5/2
7:00 am-3:33 pm
1 stop9h 33m
Boise Air Term. Gowen Fld
Tue 5/5
2:57 pm-11:59 pm
1 stop8h 02m
$317
St. LouisIdaho Falls
STL - IDA
STLIDA
Lambert-St Louis
Tue 4/14
6:45 pm-10:40 pm
1 stop4h 55m
Idaho Falls Fanning Field
Sat 4/18
6:58 pm-8:30 am
2 stops12h 32m
$354
St. LouisSpokane
STL - GEG
STLGEG
Lambert-St Louis
Sat 5/2
6:30 am-3:18 pm
2 stops10h 48m
Spokane
Sat 5/30
1:41 pm-8:57 pm
1 stop5h 16m
$357
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Mon 4/27
6:45 pm-11:57 pm
1 stop6h 12m
Boise Air Term. Gowen Fld
Wed 5/6
2:18 pm-11:35 pm
1 stop8h 17m
$361
St. LouisSpokane
STL - GEG
STLGEG
Lambert-St Louis
Wed 5/6
6:35 am-1:45 pm
2 stops9h 10m
Spokane
Fri 5/8
5:50 am-3:50 pm
2 stops8h 00m
$397
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Wed 5/20
5:36 pm-11:46 pm
1 stop7h 10m
Boise Air Term. Gowen Fld
Thu 5/28
6:41 pm-12:30 am
1 stop4h 49m
$405
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Sat 5/2
10:25 am-9:17 pm
2 stops11h 52m
Boise Air Term. Gowen Fld
Tue 5/5
2:26 pm-8:43 pm
1 stop5h 17m
$412
St. LouisIdaho Falls
STL - IDA
STLIDA
Lambert-St Louis
Wed 5/27
5:10 am-9:50 am
1 stop5h 40m
Idaho Falls Fanning Field
Thu 6/11
4:10 pm-11:57 pm
1 stop6h 47m
$414
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Tue 4/28
4:30 pm-9:22 pm
1 stop5h 52m
Boise Air Term. Gowen Fld
Wed 4/29
2:37 pm-8:54 pm
1 stop5h 17m
$417
St. LouisSpokane
STL - GEG
STLGEG
Lambert-St Louis
Sat 5/2
8:45 am-4:05 pm
2 stops9h 20m
Spokane
Sat 5/30
6:15 am-6:10 pm
2 stops9h 55m
$425
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-WYS
STL-GEG
STL-IDA
STL-JAC
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.
Cheapflights Insights
Everything you need to know about your flight from St. Louis to Idaho
STL-USID
STL-BOI
STL-WYS
STL-GEG
STL-IDA
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 $556). 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 April 2, 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.
Comfort
8.0
Entertainment
7.5
Boarding
8.1
Overall
8.0
Crew
8.6
Food
7.0
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Comfort
8.0
Entertainment
7.5
Boarding
8.1
Overall
8.0
Crew
8.6
Food
7.0
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Comfort
8.0
Entertainment
7.5
Boarding
8.1
Overall
8.0
Crew
8.6
Food
7.0
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Comfort
8.0
Entertainment
7.5
Boarding
8.1
Overall
8.0
Crew
8.6
Food
7.0
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Comfort
8.0
Entertainment
7.5
Boarding
8.1
Overall
8.0
Crew
8.6
Food
7.0
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
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
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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 April 2, 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 April 2, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$163 | Average$375 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$186 | Average$366 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$290 | Average$468 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$296 | Average$421 | FlexibilityNo cancel fee | On-time63% |