$117+ 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 5/27. Fares are subject to change and may not be available on all flights or dates of travel.
STL — BOI
May 25 — Jun 11
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 April 25, 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 25, 2026.
This American Airlines deal was found by Cheapflights users on 4/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/27:00 am
STL
- BOI
1 stop8h 20m
American Airlines
Tue 6/93:11 pm
BOI
- STL
1 stop7h 45m
American Airlines
Deal found 4/20![American Airlines logo]()
$263
This Delta deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/35:36 pm
STL
- BOI
1 stop8h 12m
Delta
Mon 6/811:45 pm
BOI
- STL
1 stop7h 31m
Delta
Deal found 4/22![Delta logo]()
$290
This Southwest deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/32:30 pm
STL
- BOI
2 stops8h 40m
Southwest
Mon 6/85:55 pm
BOI
- STL
1 stop6h 55m
Southwest
Deal found 4/22![Southwest logo]()
$311
This Southwest deal was found by Cheapflights users on 4/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/25:40 pm
STL
- BOI
2 stops7h 45m
Southwest
Tue 6/94:05 pm
BOI
- STL
1 stop6h 50m
Southwest
Deal found 4/20![Southwest logo]()
$316
This Delta deal was found by Cheapflights users on 4/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/277:00 am
STL
- WYS
1 stop6h 25m
Delta
Mon 6/11:10 pm
WYS
- STL
1 stop4h 53m
Delta
Deal found 4/24![Delta logo]()
$324
This Kiwi.com deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/36:51 pm
STL
- BOI
2 stops18h 47m
Frontier
Sun 6/71:33 pm
BOI
- STL
1 stop28h 50m
Frontier
Deal found 4/22![Frontier logo]()
$330
This Delta deal was found by Cheapflights users on 4/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/277:00 am
STL
- WYS
1 stop6h 25m
Delta
Tue 6/21:10 pm
WYS
- STL
2 stops9h 11m
Delta
Deal found 4/24![Delta logo]()
$334
This Southwest deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/45:00 pm
STL
- BOI
1 stop7h 20m
Southwest
Tue 8/182:20 pm
BOI
- STL
1 stop7h 25m
Southwest
Deal found 4/22![Southwest logo]()
$335
This Delta deal was found by Cheapflights users on 4/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/207:59 pm
STL
- BOI
1 stop5h 05m
Delta
Thu 5/2811:39 pm
BOI
- STL
1 stop9h 05m
Delta
Deal found 4/23![Delta logo]()
$337
This United Airlines deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/275:10 am
STL
- IDA
1 stop5h 40m
United Airlines
Sat 5/305:54 pm
IDA
- STL
1 stop5h 03m
United Airlines
Deal found 4/22![United Airlines logo]()
$339
This Alaska Airlines deal was found by Cheapflights users on 4/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/265:33 pm
STL
- GEG
1 stop7h 33m
Alaska Airlines
Wed 5/275:00 am
GEG
- STL
1 stop8h 16m
Alaska Airlines
Deal found 4/20![Alaska Airlines logo]()
$341
This American Airlines deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/297:00 am
STL
- GEG
1 stop8h 14m
American Airlines
Tue 6/212:51 pm
GEG
- STL
1 stop6h 51m
American Airlines
Deal found 4/22![American Airlines logo]()
$354
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 25, 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 25, 2026.
This Alaska Airlines deal was found by Cheapflights users on 4/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/265:33 pm
STL
- GEG
1 stop7h 33m
Alaska Airlines
Wed 5/2712:46 pm
GEG
- STL
1 stop9h 08m
Alaska Airlines
Deal found 4/21![Alaska Airlines logo]()
$343
This Delta deal was found by Cheapflights users on 4/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/121:30 pm
STL
- JAC
1 stop7h 53m
Delta
Fri 9/185:30 pm
JAC
- STL
1 stop6h 06m
Delta
Deal found 4/19![Delta logo]()
$359
This United Airlines deal was found by Cheapflights users on 4/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/286:00 am
STL
- BOI
1 stop6h 32m
United Airlines
Sun 5/315:46 pm
BOI
- STL
1 stop5h 11m
United Airlines
Deal found 4/21![United Airlines logo]()
$392
This American Airlines deal was found by Cheapflights users on 4/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/307:00 am
STL
- BOI
1 stop8h 20m
American Airlines
Tue 7/73:06 pm
BOI
- STL
1 stop7h 50m
American Airlines
Deal found 4/19![American Airlines logo]()
$407
This Southwest deal was found by Cheapflights users on 4/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/46:40 pm
STL
- GEG
2 stops8h 40m
Southwest
Mon 6/85:10 pm
GEG
- STL
1 stop6h 45m
Southwest
Deal found 4/20![Southwest logo]()
$425
This Alaska Airlines deal was found by Cheapflights users on 4/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/155:33 pm
STL
- IDA
1 stop20h 44m
Alaska Airlines
Fri 5/224:03 pm
IDA
- STL
1 stop23h 34m
Alaska Airlines
Deal found 4/21![Alaska Airlines logo]()
$379
This Delta deal was found by Cheapflights users on 4/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/238:49 am
STL
- JAC
2 stops9h 10m
Delta
Mon 6/296:06 pm
JAC
- STL
1 stop5h 33m
Delta
Deal found 4/23![Delta logo]()
$380
This Delta deal was found by Cheapflights users on 4/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/207:59 pm
STL
- BOI
1 stop5h 05m
Delta
Thu 5/289:16 pm
BOI
- STL
2 stops12h 16m
Delta
Deal found 4/23![Delta logo]()
$386
This Alaska Airlines deal was found by Cheapflights users on 4/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/27:41 pm
STL
- GEG
1 stop6h 18m
Alaska Airlines
Wed 6/312:46 pm
GEG
- STL
1 stop9h 08m
Alaska Airlines
Deal found 4/19![Alaska Airlines logo]()
$390
This Southwest deal was found by Cheapflights users on 4/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/1012:40 pm
STL
- BOI
1 stop5h 35m
Southwest
Wed 7/154:05 pm
BOI
- STL
1 stop5h 05m
Southwest
Deal found 4/19![Southwest logo]()
$437
This United Airlines deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/55:10 am
STL
- IDA
1 stop5h 40m
United Airlines
Mon 8/102:30 pm
IDA
- STL
1 stop5h 13m
United Airlines
Deal found 4/22![United Airlines logo]()
$450
This Southwest deal was found by Cheapflights users on 4/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/236:05 am
STL
- GEG
1 stop9h 40m
Southwest
Sat 5/3010:45 am
GEG
- STL
2 stops7h 35m
Southwest
Deal found 4/19![Southwest logo]()
$445
This United Airlines deal was found by Cheapflights users on 4/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/234:48 pm
STL
- JAC
1 stop5h 10m
United Airlines
Mon 6/298:00 am
JAC
- STL
1 stop9h 17m
United Airlines
Deal found 4/19![United Airlines logo]()
$454
This Delta deal was found by Cheapflights users on 4/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/2711:25 am
STL
- WYS
2 stops26h 00m
Delta
Tue 6/21:10 pm
WYS
- STL
2 stops9h 11m
Delta
Deal found 4/24![Delta logo]()
$414
This Expedia deal was found by Cheapflights users on 4/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/147:41 pm
STL
- IDA
1 stop20h 45m
Alaska Airlines
Sun 5/176:00 am
IDA
- STL
1 stop8h 16m
Alaska Airlines
Deal found 4/24![Alaska Airlines logo]()
$434
This United Airlines deal was found by Cheapflights users on 4/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/155:10 am
STL
- JAC
1 stop5h 36m
United Airlines
Mon 6/224:23 pm
JAC
- STL
1 stop6h 34m
United Airlines
Deal found 4/19![United Airlines logo]()
$456
This Southwest deal was found by Cheapflights users on 4/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/34:00 pm
STL
- BOI
1 stop7h 55m
Southwest
Fri 7/103:25 pm
BOI
- STL
2 stops7h 45m
Southwest
Deal found 4/23![Southwest logo]()
$458
This Delta deal was found by Cheapflights users on 4/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/38:49 am
STL
- BOI
1 stop6h 02m
Delta
Fri 7/1011:42 pm
BOI
- STL
1 stop8h 24m
Delta
Deal found 4/23![Delta logo]()
$437
This United Airlines deal was found by Cheapflights users on 4/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/911:15 am
STL
- BOI
2 stops11h 02m
United Airlines
Sat 5/162:33 pm
BOI
- STL
1 stop5h 10m
United Airlines
Deal found 4/19![United Airlines logo]()
$457
This Southwest deal was found by Cheapflights users on 4/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/84:00 pm
STL
- BOI
2 stops8h 20m
Southwest
Sat 7/116:40 am
BOI
- STL
2 stops12h 20m
Southwest
Deal found 4/21![Southwest logo]()
$458
This Delta deal was found by Cheapflights users on 4/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/28:00 am
STL
- PIH
2 stops11h 25m
Delta
Wed 7/87:00 pm
PIH
- STL
1 stop4h 37m
Delta
Deal found 4/20![Delta logo]()
$462
This Southwest deal was found by Cheapflights users on 4/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 7/122:10 pm
STL
- GEG
2 stops12h 35m
Southwest
Wed 7/152:55 pm
GEG
- STL
1 stop7h 00m
Southwest
Deal found 4/21![Southwest logo]()
$467
This United Airlines deal was found by Cheapflights users on 4/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/225:10 am
STL
- IDA
1 stop5h 40m
United Airlines
Mon 7/274:10 pm
IDA
- STL
1 stop6h 47m
United Airlines
Deal found 4/19![United Airlines logo]()
$471
This Alaska Airlines deal was found by Cheapflights users on 4/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/155:33 pm
STL
- IDA
1 stop20h 44m
Alaska Airlines
Tue 5/196:00 am
IDA
- STL
2 stops9h 37m
Alaska Airlines
Deal found 4/24![Alaska Airlines logo]()
$554
This Delta deal was found by Cheapflights users on 4/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/22:28 pm
STL
- JAC
1 stop8h 01m
Delta
Fri 8/76:06 pm
JAC
- STL
1 stop5h 31m
Delta
Deal found 4/23![Delta logo]()
$468
This Southwest deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 6/204:45 pm
STL
- GEG
2 stops9h 20m
Southwest
Fri 6/262:15 pm
GEG
- STL
2 stops8h 20m
Southwest
Deal found 4/22![Southwest logo]()
$481
This United Airlines deal was found by Cheapflights users on 4/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/25:10 am
STL
- IDA
1 stop5h 40m
United Airlines
Wed 7/82:30 pm
IDA
- STL
1 stop5h 13m
United Airlines
Deal found 4/20![United Airlines logo]()
$497
This Delta deal was found by Cheapflights users on 4/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/21:30 pm
STL
- JAC
1 stop7h 53m
Delta
Sun 9/65:30 pm
JAC
- STL
1 stop6h 06m
Delta
Deal found 4/23![Delta logo]()
$477
This Southwest deal was found by Cheapflights users on 4/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/233:10 pm
STL
- GEG
2 stops9h 05m
Southwest
Sat 6/272:20 pm
GEG
- STL
1 stop7h 25m
Southwest
Deal found 4/19![Southwest logo]()
$502
This United Airlines deal was found by Cheapflights users on 4/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 6/204:45 pm
STL
- JAC
1 stop5h 13m
United Airlines
Wed 6/244:23 pm
JAC
- STL
1 stop6h 34m
United Airlines
Deal found 4/21![United Airlines logo]()
$510
Last-minute flights from St. Louis to IdahoDiscover last-minute flight deals from St. Louis to Idaho. Data last updated April 25, 2026 and is based on user searches.
Discover last-minute flight deals from St. Louis to Idaho. Data last updated April 25, 2026 and is based on user searches.
This Delta deal was found by Cheapflights users on 4/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/137:00 am
STL
- GEG
1 stop7h 01m
Delta
Thu 5/1410:40 pm
GEG
- STL
1 stop7h 30m
Delta
Deal found 4/23![Delta logo]()
$363
This Delta deal was found by Cheapflights users on 4/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/147:00 am
STL
- BOI
1 stop5h 56m
Delta
Tue 5/196:41 pm
BOI
- STL
1 stop4h 49m
Delta
Deal found 4/23![Delta logo]()
$366
This Delta deal was found by Cheapflights users on 4/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/207:59 pm
STL
- BOI
1 stop5h 05m
Delta
Thu 5/2811:39 pm
BOI
- STL
1 stop9h 05m
Delta
Deal found 4/23![Delta logo]()
$337
This United Airlines deal was found by Cheapflights users on 4/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/239:06 am
STL
- GEG
1 stop8h 06m
United Airlines
Sat 5/301:41 pm
GEG
- STL
1 stop5h 16m
United Airlines
Deal found 4/19![United Airlines logo]()
$357
This United Airlines deal was found by Cheapflights users on 4/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/241:38 pm
STL
- JAC
1 stop5h 16m
United Airlines
Sat 5/308:00 am
JAC
- STL
1 stop9h 17m
United Airlines
Deal found 4/19![United Airlines logo]()
$359
This Alaska Airlines deal was found by Cheapflights users on 4/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/265:33 pm
STL
- GEG
1 stop7h 33m
Alaska Airlines
Wed 5/275:00 am
GEG
- STL
1 stop8h 16m
Alaska Airlines
Deal found 4/20![Alaska Airlines logo]()
$341
This Delta deal was found by Cheapflights users on 4/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/277:00 am
STL
- WYS
1 stop6h 25m
Delta
Mon 6/11:10 pm
WYS
- STL
1 stop4h 53m
Delta
Deal found 4/24![Delta logo]()
$324
This Delta deal was found by Cheapflights users on 4/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/277:00 am
STL
- WYS
1 stop6h 25m
Delta
Tue 6/21:10 pm
WYS
- STL
2 stops9h 11m
Delta
Deal found 4/24![Delta logo]()
$334
This United Airlines deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/275:10 am
STL
- IDA
1 stop5h 40m
United Airlines
Sat 5/305:54 pm
IDA
- STL
1 stop5h 03m
United Airlines
Deal found 4/22![United Airlines logo]()
$339
This Delta deal was found by Cheapflights users on 4/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/277:00 am
STL
- JAC
1 stop6h 20m
Delta
Thu 6/45:59 pm
JAC
- STL
1 stop5h 31m
Delta
Deal found 4/24![Delta logo]()
$375
This American Airlines deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/297:00 am
STL
- GEG
1 stop8h 14m
American Airlines
Tue 6/212:51 pm
GEG
- STL
1 stop6h 51m
American Airlines
Deal found 4/22![American Airlines logo]()
$354
This Southwest deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/295:15 pm
STL
- GEG
1 stop7h 05m
Southwest
Tue 6/210:55 am
GEG
- STL
2 stops9h 05m
Southwest
Deal found 4/22![Southwest logo]()
$361
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 25, 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 25, 2026.
This CheapOair deal was found by Cheapflights users on 4/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/278:08 pm
STL
- BOI
1 stop17h 22m
Frontier
Deal found 4/20![Frontier logo]()
$117
This CheapOair deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/48:08 pm
STL
- BOI
1 stop17h 01m
Frontier
Deal found 4/22![Frontier logo]()
$151
This CheapOair deal was found by Cheapflights users on 4/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/168:08 pm
STL
- BOI
1 stop17h 19m
Frontier
Deal found 4/23![Frontier logo]()
$157
This Alaska Airlines deal was found by Cheapflights users on 4/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/115:37 pm
STL
- JAC
1 stop20h 54m
Alaska Airlines
Deal found 4/23![Alaska Airlines logo]()
$185
This Expedia deal was found by Cheapflights users on 4/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/145:37 pm
STL
- JAC
2 stops22h 30m
Alaska Airlines
Deal found 4/19![Alaska Airlines logo]()
$191
This Kiwi.com deal was found by Cheapflights users on 4/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/247:46 pm
STL
- GEG
1 stop26h 11m
Multiple Airlines
Deal found 4/21![Multiple Airlines logo]()
$192
This Kiwi.com deal was found by Cheapflights users on 4/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/154:19 pm
STL
- GEG
2 stops54h 10m
Multiple Airlines
Deal found 4/21![Multiple Airlines logo]()
$198
This Southwest deal was found by Cheapflights users on 4/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/202:30 pm
STL
- BOI
1 stop10h 55m
Southwest
Deal found 4/21![Southwest logo]()
$202
This United Airlines deal was found by Cheapflights users on 4/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/138:46 am
STL
- IDA
1 stop7h 57m
United Airlines
Deal found 4/20![United Airlines logo]()
$203
This American Airlines deal was found by Cheapflights users on 4/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/78:36 am
STL
- BOI
1 stop7h 12m
American Airlines
Deal found 4/21![American Airlines logo]()
$204
This United Airlines deal was found by Cheapflights users on 4/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/152:35 pm
STL
- GEG
1 stop8h 41m
United Airlines
Deal found 4/21![United Airlines logo]()
$208
This Southwest deal was found by Cheapflights users on 4/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/165:20 pm
STL
- BOI
2 stops8h 05m
Southwest
Deal found 4/23![Southwest logo]()
$209
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 25, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $263 (American Airlines) |
One-way from | $117 (CheapOair) |
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 25, 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
Tue 5/26
5:33 pm-11:06 pm
1 stop7h 33m
Spokane
Wed 5/27
12:46 pm-11:54 pm
1 stop9h 08m
$343
St. LouisJackson
STL - JAC
STLJAC
Lambert-St Louis
Sat 9/12
1:30 pm-8:23 pm
1 stop7h 53m
Jackson Hole
Fri 9/18
5:30 pm-12:36 am
1 stop6h 06m
$359
St. LouisIdaho Falls
STL - IDA
STLIDA
Lambert-St Louis
Fri 5/15
5:33 pm-1:17 pm
1 stop20h 44m
Idaho Falls Fanning Field
Fri 5/22
4:03 pm-4:37 pm
1 stop23h 34m
$379
St. LouisJackson
STL - JAC
STLJAC
Lambert-St Louis
Tue 6/23
8:49 am-4:59 pm
2 stops9h 10m
Jackson Hole
Mon 6/29
6:06 pm-12:39 am
1 stop5h 33m
$380
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Wed 5/20
7:59 pm-12:04 am
1 stop5h 05m
Boise Air Term. Gowen Fld
Thu 5/28
9:16 pm-10:32 am
2 stops12h 16m
$386
St. LouisSpokane
STL - GEG
STLGEG
Lambert-St Louis
Tue 6/2
7:41 pm-11:59 pm
1 stop6h 18m
Spokane
Wed 6/3
12:46 pm-11:54 pm
1 stop9h 08m
$390
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Thu 5/28
6:00 am-11:32 am
1 stop6h 32m
Boise Air Term. Gowen Fld
Sun 5/31
5:46 pm-11:57 pm
1 stop5h 11m
$392
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Tue 6/30
7:00 am-2:20 pm
1 stop8h 20m
Boise Air Term. Gowen Fld
Tue 7/7
3:06 pm-11:56 pm
1 stop7h 50m
$407
St. LouisWest Yellowstone
STL - WYS
STLWYS
Lambert-St Louis
Wed 5/27
11:25 am-12:25 pm
2 stops26h 00m
West Yellowstone
Tue 6/2
1:10 pm-11:21 pm
2 stops9h 11m
$414
St. LouisSpokane
STL - GEG
STLGEG
Lambert-St Louis
Thu 6/4
6:40 pm-1:20 am
2 stops8h 40m
Spokane
Mon 6/8
5:10 pm-1:55 am
1 stop6h 45m
$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-IDA
STL-BOI
STL-GEG
STL-JAC
STL-WYS
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-IDA
STL-BOI
STL-GEG
STL-JAC
How far ahead should I book a flight from St. Louis to Idaho?
The price you pay for your flight from St. Louis to Idaho may vary depending on when you book. For the best chance of a lower fare, look to book 60 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.
What is the cheapest month to book a flight from St. Louis to Idaho?
Currently, July is the cheapest month in which you can book a flight from St. Louis to Idaho (average of $104). 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 April 25, 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
Comfort
8.0
Boarding
8.1
Food
7.0
Crew
8.6
Overall
8.0
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Entertainment
7.5
Comfort
8.0
Boarding
8.1
Food
7.0
Crew
8.6
Overall
8.0
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Entertainment
7.5
Comfort
8.0
Boarding
8.1
Food
7.0
Crew
8.6
Overall
8.0
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Entertainment
7.5
Comfort
8.0
Boarding
8.1
Food
7.0
Crew
8.6
Overall
8.0
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Entertainment
7.5
Comfort
8.0
Boarding
8.1
Food
7.0
Crew
8.6
Overall
8.0
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
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St. Louis and Idaho flights
Browse other St. Louis and Idaho flight options. Last updated on April 25, 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 25, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$163 | Average$373 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$186 | Average$366 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$290 | Average$461 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$296 | Average$442 | FlexibilityNo cancel fee | On-time63% |