$112+ 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 4/8. Fares are subject to change and may not be available on all flights or dates of travel.
STL — BOI
Apr 17 — Apr 241
Round-trip
1 adult, Economy
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Find cheap flights from St. Louis to Idaho with Cheapflights
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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 March 18, 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 March 18, 2026.
This Gotogate deal was found by Cheapflights users on 3/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/88:16 pm
STL
- GEG
1 stop16h 05m
Frontier
Sun 4/1211:06 am
GEG
- STL
1 stop20h 42m
Frontier
Deal found 3/14![Frontier logo]()
$239
This Alaska Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/73:50 pm
STL
- BOI
1 stop8h 07m
Alaska Airlines
Wed 4/82:22 pm
BOI
- STL
1 stop8h 37m
Alaska Airlines
Deal found 3/12![Alaska Airlines logo]()
$277
This Southwest deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” 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 5/65:30 am
STL
- BOI
2 stops8h 00m
Southwest
Wed 5/134:05 pm
BOI
- STL
1 stop6h 10m
Southwest
Deal found 3/15![Southwest logo]()
$282
This Delta deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” 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
- GEG
1 stop6h 49m
Delta
Sat 4/185:30 am
GEG
- STL
1 stop7h 31m
Delta
Deal found 3/17![Delta logo]()
$331
This Southwest deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/156:35 am
STL
- GEG
1 stop5h 40m
Southwest
Sat 4/1810:45 am
GEG
- STL
2 stops7h 35m
Southwest
Deal found 3/17![Southwest logo]()
$336
This American Airlines deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” 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 4/295:20 am
STL
- JAC
1 stop8h 21m
American Airlines
Wed 5/61:25 pm
JAC
- STL
1 stop8h 34m
American Airlines
Deal found 3/15![American Airlines logo]()
$336
This Delta deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” 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 5/36:45 pm
STL
- IDA
1 stop4h 55m
Delta
Sat 5/93:16 pm
IDA
- STL
1 stop4h 50m
Delta
Deal found 3/16![Delta logo]()
$339
This American Airlines deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” 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.
Mon 4/135:20 am
STL
- JAC
1 stop8h 21m
American Airlines
Mon 4/201:25 pm
JAC
- STL
1 stop8h 34m
American Airlines
Deal found 3/15![American Airlines logo]()
$339
This Delta deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” 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 5/36:45 pm
STL
- IDA
1 stop4h 55m
Delta
Tue 5/123:16 pm
IDA
- STL
2 stops7h 05m
Delta
Deal found 3/16![Delta logo]()
$344
This CheapOair deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” 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 4/18:16 pm
STL
- BOI
1 stop15h 52m
Frontier
Sun 4/512:03 pm
BOI
- STL
1 stop20h 45m
Frontier
Deal found 3/16![Frontier logo]()
$347
This Delta deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/56:45 pm
STL
- IDA
1 stop4h 55m
Delta
Sat 5/96:00 am
IDA
- STL
1 stop6h 32m
Delta
Deal found 3/16![Delta logo]()
$348
This Kiwi.com deal was found by Cheapflights users on 3/13. Clicking the “Pick Dates” 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 4/88:16 pm
STL
- GEG
1 stop16h 05m
Multiple Airlines
Sun 4/129:19 pm
GEG
- STL
2 stops48h 00m
Multiple Airlines
Deal found 3/13![Multiple Airlines logo]()
$350
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 March 18, 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 March 18, 2026.
This Alaska Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/73:50 pm
STL
- BOI
1 stop8h 07m
Alaska Airlines
Wed 4/82:22 pm
BOI
- STL
1 stop8h 37m
Alaska Airlines
Deal found 3/12![Alaska Airlines logo]()
$277
This United Airlines deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” 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 7/201:13 pm
STL
- JAC
1 stop6h 29m
United Airlines
Sat 7/258:00 am
JAC
- STL
1 stop9h 17m
United Airlines
Deal found 3/15![United Airlines logo]()
$359
This Southwest deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/228:25 am
STL
- BOI
2 stops9h 00m
Southwest
Sun 4/264:10 pm
BOI
- STL
1 stop6h 35m
Southwest
Deal found 3/12![Southwest logo]()
$369
This Delta deal was found by Cheapflights users on 3/13. Clicking the “Pick Dates” 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 5/26:48 am
STL
- JAC
2 stops10h 25m
Delta
Fri 5/81:15 pm
JAC
- STL
2 stops9h 06m
Delta
Deal found 3/13![Delta logo]()
$397
This United Airlines deal was found by Cheapflights users on 3/13. Clicking the “Pick Dates” 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 6/95:10 am
STL
- JAC
1 stop5h 36m
United Airlines
Tue 6/164:23 pm
JAC
- STL
1 stop6h 34m
United Airlines
Deal found 3/13![United Airlines logo]()
$359
This Southwest deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” 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 5/16:45 pm
STL
- GEG
1 stop5h 35m
Southwest
Sat 5/1610:45 am
GEG
- STL
2 stops7h 40m
Southwest
Deal found 3/16![Southwest logo]()
$372
This United Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” 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 4/78:54 am
STL
- BOI
2 stops12h 19m
United Airlines
Wed 4/85:00 am
BOI
- STL
1 stop7h 08m
United Airlines
Deal found 3/12![United Airlines logo]()
$362
This Alaska Airlines deal was found by Cheapflights users on 3/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/284:46 pm
STL
- GEG
1 stop6h 45m
Alaska Airlines
Wed 4/296:00 am
GEG
- STL
1 stop7h 50m
Alaska Airlines
Deal found 3/14![Alaska Airlines logo]()
$417
This Delta deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/97:15 am
STL
- GEG
1 stop7h 30m
Delta
Mon 4/1310:40 pm
GEG
- STL
1 stop7h 50m
Delta
Deal found 3/17![Delta logo]()
$425
This Southwest deal was found by Cheapflights users on 3/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/105:15 pm
STL
- BOI
2 stops8h 45m
Southwest
Wed 4/153:15 pm
BOI
- STL
1 stop5h 30m
Southwest
Deal found 3/14![Southwest logo]()
$407
This Delta deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” 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 4/54:21 pm
STL
- BOI
1 stop7h 14m
Delta
Sat 4/116:00 am
BOI
- STL
1 stop7h 43m
Delta
Deal found 3/17![Delta logo]()
$442
This United Airlines deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” 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 4/289:10 am
STL
- GEG
2 stops14h 01m
United Airlines
Wed 4/291:46 pm
GEG
- STL
1 stop5h 08m
United Airlines
Deal found 3/16![United Airlines logo]()
$402
This Southwest deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/176:45 pm
STL
- BOI
1 stop5h 45m
Southwest
Mon 4/204:20 pm
BOI
- STL
1 stop6h 30m
Southwest
Deal found 3/16![Southwest logo]()
$417
This Alaska Airlines deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” 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 8/135:07 am
GEG
- STL
1 stop6h 48m
Alaska Airlines
Deal found 3/15![Alaska Airlines logo]()
$462
This Delta deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/3012:23 pm
STL
- BOI
2 stops10h 01m
Delta
Mon 5/41:52 pm
BOI
- STL
2 stops9h 33m
Delta
Deal found 3/16![Delta logo]()
$442
This United Airlines deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” 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 6/31:38 pm
STL
- GEG
2 stops12h 13m
United Airlines
Wed 6/174:08 pm
GEG
- STL
1 stop5h 49m
United Airlines
Deal found 3/17![United Airlines logo]()
$425
This Delta deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” 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 4/16:32 am
STL
- IDA
2 stops12h 43m
Delta
Sun 4/55:45 am
IDA
- STL
1 stop6h 32m
Delta
Deal found 3/16![Delta logo]()
$445
This Southwest deal was found by Cheapflights users on 3/13. Clicking the “Pick Dates” 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 6/117:45 pm
STL
- BOI
1 stop6h 20m
Southwest
Mon 6/153:25 pm
BOI
- STL
2 stops7h 45m
Southwest
Deal found 3/13![Southwest logo]()
$446
This United Airlines deal was found by Cheapflights users on 3/13. Clicking the “Pick Dates” 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 9/125:10 am
STL
- JAC
2 stops9h 40m
United Airlines
Thu 9/179:45 am
JAC
- STL
1 stop7h 39m
United Airlines
Deal found 3/13![United Airlines logo]()
$444
This Southwest deal was found by Cheapflights users on 3/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/175:45 am
STL
- GEG
2 stops9h 05m
Southwest
Sun 4/192:55 pm
GEG
- STL
1 stop9h 00m
Southwest
Deal found 3/13![Southwest logo]()
$447
This Delta deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” 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 3/17![Delta logo]()
$450
This Delta deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” 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 7/45:30 pm
STL
- IDA
1 stop5h 44m
Delta
Thu 7/96:50 pm
IDA
- STL
1 stop4h 46m
Delta
Deal found 3/16![Delta logo]()
$459
This United Airlines deal was found by Cheapflights users on 3/14. Clicking the “Pick Dates” 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 5/58:46 am
STL
- IDA
1 stop5h 39m
United Airlines
Sat 5/92:31 pm
IDA
- STL
1 stop5h 12m
United Airlines
Deal found 3/14![United Airlines logo]()
$465
This Southwest deal was found by Cheapflights users on 3/13. Clicking the “Pick Dates” 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 6/174:00 pm
STL
- GEG
2 stops8h 40m
Southwest
Sun 6/216:40 pm
GEG
- STL
1 stop13h 10m
Southwest
Deal found 3/13![Southwest logo]()
$473
This Southwest deal was found by Cheapflights users on 3/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/75:15 pm
STL
- GEG
2 stops9h 15m
Southwest
Sun 5/106:25 am
GEG
- STL
2 stops8h 55m
Southwest
Deal found 3/14![Southwest logo]()
$487
This Delta deal was found by Cheapflights users on 3/18. Clicking the “Pick Dates” 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 9/512:10 pm
STL
- JAC
2 stops7h 47m
Delta
Sun 9/135:30 pm
JAC
- STL
1 stop6h 06m
Delta
Deal found 3/18![Delta logo]()
$490
This United Airlines deal was found by Cheapflights users on 3/13. Clicking the “Pick Dates” 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 8/35:10 am
STL
- IDA
1 stop5h 40m
United Airlines
Sat 8/810:35 am
IDA
- STL
1 stop4h 58m
United Airlines
Deal found 3/13![United Airlines logo]()
$525
This Delta deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” 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 8/21:30 pm
STL
- JAC
1 stop7h 46m
Delta
Fri 8/75:30 pm
JAC
- STL
1 stop6h 06m
Delta
Deal found 3/15![Delta logo]()
$501
This United Airlines deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/249:06 am
STL
- IDA
1 stop7h 28m
United Airlines
Sat 7/255:54 pm
IDA
- STL
1 stop5h 03m
United Airlines
Deal found 3/17![United Airlines logo]()
$545
This Delta deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” 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 3/17![Delta logo]()
$522
Last-minute flights from St. Louis to IdahoDiscover last-minute flight deals from St. Louis to Idaho. Data last updated March 18, 2026 and is based on user searches.
Discover last-minute flight deals from St. Louis to Idaho. Data last updated March 18, 2026 and is based on user searches.
This American Airlines deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” 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 3/317:00 am
STL
- JAC
1 stop6h 38m
American Airlines
Sat 4/41:44 pm
JAC
- STL
1 stop6h 27m
American Airlines
Deal found 3/16![American Airlines logo]()
$359
This CheapOair deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” 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 4/18:16 pm
STL
- BOI
1 stop15h 52m
Frontier
Sun 4/512:03 pm
BOI
- STL
1 stop20h 45m
Frontier
Deal found 3/16![Frontier logo]()
$347
This Alaska Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/73:50 pm
STL
- BOI
1 stop8h 07m
Alaska Airlines
Wed 4/82:22 pm
BOI
- STL
1 stop8h 37m
Alaska Airlines
Deal found 3/12![Alaska Airlines logo]()
$277
This United Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” 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 4/78:54 am
STL
- BOI
2 stops12h 19m
United Airlines
Wed 4/85:00 am
BOI
- STL
1 stop7h 08m
United Airlines
Deal found 3/12![United Airlines logo]()
$362
This Gotogate deal was found by Cheapflights users on 3/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/88:16 pm
STL
- GEG
1 stop16h 05m
Frontier
Sun 4/1211:06 am
GEG
- STL
1 stop20h 42m
Frontier
Deal found 3/14![Frontier logo]()
$239
This Kiwi.com deal was found by Cheapflights users on 3/13. Clicking the “Pick Dates” 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 4/88:16 pm
STL
- GEG
1 stop16h 05m
Multiple Airlines
Sun 4/129:19 pm
GEG
- STL
2 stops48h 00m
Multiple Airlines
Deal found 3/13![Multiple Airlines logo]()
$350
This American Airlines deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” 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.
Mon 4/135:20 am
STL
- JAC
1 stop8h 21m
American Airlines
Mon 4/201:25 pm
JAC
- STL
1 stop8h 34m
American Airlines
Deal found 3/15![American Airlines logo]()
$339
This Delta deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” 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
- GEG
1 stop6h 49m
Delta
Sat 4/185:30 am
GEG
- STL
1 stop7h 31m
Delta
Deal found 3/17![Delta logo]()
$331
This Southwest deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/142:30 pm
STL
- GEG
1 stop10h 55m
Southwest
Sat 4/1810:45 am
GEG
- STL
2 stops7h 35m
Southwest
Deal found 3/17![Southwest logo]()
$352
This United Airlines deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” 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 4/1411:15 am
STL
- GEG
2 stops11h 56m
United Airlines
Sat 4/187:00 am
GEG
- STL
2 stops11h 54m
United Airlines
Deal found 3/17![United Airlines logo]()
$357
This Southwest deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/156:35 am
STL
- GEG
1 stop5h 40m
Southwest
Sat 4/1810:45 am
GEG
- STL
2 stops7h 35m
Southwest
Deal found 3/17![Southwest logo]()
$336
This American Airlines deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” 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 4/295:20 am
STL
- JAC
1 stop8h 21m
American Airlines
Wed 5/61:25 pm
JAC
- STL
1 stop8h 34m
American Airlines
Deal found 3/15![American Airlines logo]()
$336
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 March 18, 2026.
Search for one-way flight options from St. Louis to Idaho. Find affordable one-way fares based on user searches. Data last updated March 18, 2026.
This Kiwi.com deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” 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 4/88:16 pm
STL
- BOI
1 stop15h 52m
Frontier
Deal found 3/17![Frontier logo]()
$112
This Mytrip deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/318:08 pm
STL
- GEG
1 stop17h 30m
Frontier
Deal found 3/15![Frontier logo]()
$155
This Expedia deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” 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 9/103:24 pm
STL
- IDA
1 stop8h 15m
Alaska Airlines
Deal found 3/16![Alaska Airlines logo]()
$170
This Southwest deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/85:45 am
STL
- BOI
2 stops8h 35m
Southwest
Deal found 3/17![Southwest logo]()
$189
This Expedia deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” 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 7/257:56 pm
STL
- JAC
2 stops20h 11m
Alaska Airlines
Deal found 3/15![Alaska Airlines logo]()
$191
This Mytrip deal was found by Cheapflights users on 3/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/258:12 pm
STL
- BOI
1 stop16h 08m
Frontier
Deal found 3/13![Frontier logo]()
$211
This Mytrip deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/218:08 pm
STL
- GEG
1 stop17h 30m
Frontier
Deal found 3/15![Frontier logo]()
$220
This American Airlines deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” 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.
Mon 7/276:00 am
STL
- JAC
1 stop6h 59m
American Airlines
Deal found 3/15![American Airlines logo]()
$222
This United Airlines deal was found by Cheapflights users on 3/14. Clicking the “Pick Dates” 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 5/305:10 am
STL
- BOI
1 stop5h 35m
United Airlines
Deal found 3/14![United Airlines logo]()
$223
This United Airlines deal was found by Cheapflights users on 3/13. Clicking the “Pick Dates” 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 4/36:30 am
STL
- BOI
1 stop6h 19m
United Airlines
Deal found 3/13![United Airlines logo]()
$226
This Southwest deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” 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 7/306:45 pm
STL
- GEG
1 stop8h 35m
Southwest
Deal found 3/16![Southwest logo]()
$229
This United Airlines deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” 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 7/261:13 pm
STL
- JAC
1 stop6h 29m
United Airlines
Deal found 3/15![United Airlines logo]()
$232
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 March 18, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $239 (Gotogate) |
One-way from | $112 (Kiwi.com) |
Popular in | February |
Cheapest in | January |
Average price | $538 |
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 March 18, 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
Tue 4/7
3:50 pm-10:57 pm
1 stop8h 07m
Boise Air Term. Gowen Fld
Wed 4/8
2:22 pm-11:59 pm
1 stop8h 37m
$277
St. LouisJackson
STL - JAC
STLJAC
Lambert-St Louis
Mon 7/20
1:13 pm-6:42 pm
1 stop6h 29m
Jackson Hole
Sat 7/25
8:00 am-6:17 pm
1 stop9h 17m
$359
St. LouisJackson
STL - JAC
STLJAC
Lambert-St Louis
Tue 6/9
5:10 am-9:46 am
1 stop5h 36m
Jackson Hole
Tue 6/16
4:23 pm-11:57 pm
1 stop6h 34m
$359
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Tue 4/7
8:54 am-8:13 pm
2 stops12h 19m
Boise Air Term. Gowen Fld
Wed 4/8
5:00 am-1:08 pm
1 stop7h 08m
$362
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Wed 4/22
8:25 am-4:25 pm
2 stops9h 00m
Boise Air Term. Gowen Fld
Sun 4/26
4:10 pm-11:45 pm
1 stop6h 35m
$369
St. LouisSpokane
STL - GEG
STLGEG
Lambert-St Louis
Fri 5/1
6:45 pm-10:20 pm
1 stop5h 35m
Spokane
Sat 5/16
10:45 am-8:25 pm
2 stops7h 40m
$372
St. LouisJackson
STL - JAC
STLJAC
Lambert-St Louis
Sat 5/2
6:48 am-4:13 pm
2 stops10h 25m
Jackson Hole
Fri 5/8
1:15 pm-11:21 pm
2 stops9h 06m
$397
St. LouisSpokane
STL - GEG
STLGEG
Lambert-St Louis
Tue 4/28
9:10 am-9:11 pm
2 stops14h 01m
Spokane
Wed 4/29
1:46 pm-8:54 pm
1 stop5h 08m
$402
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Fri 4/10
5:15 pm-1:00 am
2 stops8h 45m
Boise Air Term. Gowen Fld
Wed 4/15
3:15 pm-9:45 pm
1 stop5h 30m
$407
St. LouisSpokane
STL - GEG
STLGEG
Lambert-St Louis
Tue 4/28
4:46 pm-9:31 pm
1 stop6h 45m
Spokane
Wed 4/29
6:00 am-3:50 pm
1 stop7h 50m
$417
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-GEG
STL-BOI
STL-JAC
STL-IDA
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-GEG
STL-BOI
STL-JAC
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.
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 March 18, 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
Crew
8.6
Boarding
8.1
Food
7.0
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
Comfort
8.0
Crew
8.6
Boarding
8.1
Food
7.0
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
Comfort
8.0
Crew
8.6
Boarding
8.1
Food
7.0
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
Comfort
8.0
Crew
8.6
Boarding
8.1
Food
7.0
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
Comfort
8.0
Crew
8.6
Boarding
8.1
Food
7.0
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
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 March 18, 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 March 18, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$163 | Average$372 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$186 | Average$366 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$290 | Average$460 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$292 | Average$408 | FlexibilityNo cancel fee | On-time63% |