$119+ 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 4/29. Fares are subject to change and may not be available on all flights or dates of travel.
STL — BOI
Mar 5 — Mar 121
1 adult, Economy
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Find cheap flights from St. Louis to Idaho with Cheapflights
1. Tell us where you want to go
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 February 3, 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 February 3, 2026.
This Kiwi.com deal was found by Cheapflights users on 2/1. 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 3/78:12 pm
STL
- BOI
1 stop15h 08m
Frontier
Thu 3/1212:15 pm
BOI
- STL
1 stop20h 34m
Frontier
Deal found 2/1![Frontier logo]()
$152
This Alaska Airlines deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/37:00 am
STL
- GEG
1 stop7h 29m
Alaska Airlines
Wed 3/45:40 am
GEG
- STL
1 stop6h 11m
Alaska Airlines
Deal found 2/1![Alaska Airlines logo]()
$237
This Delta deal was found by Cheapflights users on 2/1. 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.
Sat 3/73:40 pm
STL
- BOI
1 stop6h 15m
Delta
Tue 3/106:00 am
BOI
- STL
1 stop6h 31m
Delta
Deal found 2/1![Delta logo]()
$237
This United Airlines deal was found by Cheapflights users on 2/2. 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.
Tue 3/36:25 am
STL
- BOI
2 stops8h 13m
United Airlines
Tue 3/105:31 pm
BOI
- STL
1 stop5h 03m
United Airlines
Deal found 2/2![United Airlines logo]()
$242
This Expedia deal was found by Cheapflights users on 2/2. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/234:46 pm
STL
- BOI
1 stop7h 16m
Multiple Airlines
Thu 4/3011:53 am
BOI
- STL
1 stop6h 19m
Multiple Airlines
Deal found 2/2![Multiple Airlines logo]()
$258
This American Airlines deal was found by Cheapflights users on 2/2. 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.
Thu 3/56:00 am
STL
- GEG
1 stop7h 44m
American Airlines
Tue 3/103:10 pm
GEG
- STL
1 stop6h 49m
American Airlines
Deal found 2/2![American Airlines logo]()
$264
This Delta deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/47:00 am
STL
- BOI
2 stops15h 56m
Delta
Wed 3/116:15 pm
BOI
- STL
1 stop5h 06m
Delta
Deal found 2/1![Delta logo]()
$265
This United Airlines deal was found by Cheapflights users on 2/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/52:50 pm
STL
- GEG
1 stop8h 28m
United Airlines
Tue 3/107:02 am
GEG
- STL
2 stops11h 39m
United Airlines
Deal found 2/2![United Airlines logo]()
$269
This Delta deal was found by Cheapflights users on 2/1. 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.
Sat 3/76:00 am
STL
- BOI
1 stop7h 31m
Delta
Mon 3/910:35 am
BOI
- STL
2 stops12h 46m
Delta
Deal found 2/1![Delta logo]()
$275
This United Airlines deal was found by Cheapflights users on 2/1. 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 3/38:41 am
STL
- IDA
1 stop5h 49m
United Airlines
Tue 3/105:30 pm
IDA
- STL
1 stop5h 04m
United Airlines
Deal found 2/1![United Airlines logo]()
$279
This Delta deal was found by Cheapflights users on 2/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 4/56:12 pm
STL
- BOI
1 stop6h 47m
Delta
Sat 4/118:00 am
BOI
- STL
1 stop5h 43m
Delta
Deal found 2/3![Delta logo]()
$281
This Delta deal was found by Cheapflights users on 2/1. 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.
Mon 5/117:59 pm
STL
- GEG
1 stop5h 36m
Delta
Sat 5/166:50 am
GEG
- STL
1 stop7h 59m
Delta
Deal found 2/1![Delta logo]()
$282
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 February 3, 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 February 3, 2026.
This Delta deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/65:35 pm
STL
- GEG
1 stop5h 30m
Delta
Sat 5/166:50 am
GEG
- STL
1 stop6h 29m
Delta
Deal found 2/1![Delta logo]()
$237
This Alaska Airlines deal was found by Cheapflights users on 1/31. 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.
Tue 3/37:00 am
STL
- GEG
1 stop7h 29m
Alaska Airlines
Wed 3/45:40 am
GEG
- STL
1 stop6h 11m
Alaska Airlines
Deal found 1/31![Alaska Airlines logo]()
$237
This United Airlines deal was found by Cheapflights users on 2/2. 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.
Tue 3/38:41 am
STL
- BOI
1 stop5h 57m
United Airlines
Tue 3/102:40 pm
BOI
- STL
1 stop7h 54m
United Airlines
Deal found 2/2![United Airlines logo]()
$237
This Kiwi.com deal was found by Cheapflights users on 2/1. 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 3/78:12 pm
STL
- BOI
1 stop15h 08m
Frontier
Thu 3/1212:15 pm
BOI
- STL
2 stops24h 19m
Frontier
Deal found 2/1![Frontier logo]()
$273
This Southwest deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/77:20 pm
STL
- GEG
1 stop7h 15m
Southwest
Sat 5/1611:05 am
GEG
- STL
1 stop7h 15m
Southwest
Deal found 2/1![Southwest logo]()
$307
This Delta deal was found by Cheapflights users on 2/1. 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.
Sat 3/77:00 am
STL
- BOI
1 stop6h 09m
Delta
Wed 3/115:30 am
BOI
- STL
1 stop7h 54m
Delta
Deal found 2/1![Delta logo]()
$237
This Delta deal was found by Cheapflights users on 2/1. 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.
Sat 3/73:40 pm
STL
- BOI
1 stop6h 15m
Delta
Tue 3/106:00 am
BOI
- STL
1 stop6h 31m
Delta
Deal found 2/1![Delta logo]()
$237
This United Airlines deal was found by Cheapflights users on 2/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/12:40 pm
STL
- BOI
1 stop7h 42m
United Airlines
Mon 4/67:03 pm
BOI
- STL
1 stop9h 47m
United Airlines
Deal found 2/2![United Airlines logo]()
$281
This Southwest deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/115:15 pm
STL
- GEG
2 stops9h 15m
Southwest
Sat 5/1611:05 am
GEG
- STL
1 stop7h 15m
Southwest
Deal found 2/1![Southwest logo]()
$312
This United Airlines deal was found by Cheapflights users on 2/1. 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 3/36:25 am
STL
- IDA
2 stops8h 05m
United Airlines
Tue 3/105:30 pm
IDA
- STL
1 stop5h 04m
United Airlines
Deal found 2/1![United Airlines logo]()
$284
This Delta deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/47:00 am
STL
- BOI
2 stops15h 56m
Delta
Wed 3/116:15 pm
BOI
- STL
1 stop5h 06m
Delta
Deal found 2/1![Delta logo]()
$265
This Delta deal was found by Cheapflights users on 2/1. 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.
Sun 4/56:12 pm
STL
- BOI
1 stop6h 47m
Delta
Sat 4/116:00 am
BOI
- STL
1 stop7h 43m
Delta
Deal found 2/1![Delta logo]()
$281
This United Airlines deal was found by Cheapflights users on 2/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/132:35 pm
STL
- GEG
1 stop8h 41m
United Airlines
Fri 5/224:03 pm
GEG
- STL
1 stop5h 55m
United Airlines
Deal found 2/3![United Airlines logo]()
$317
This Alaska Airlines deal was found by Cheapflights users on 1/31. 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.
Tue 3/37:00 am
STL
- IDA
1 stop17h 36m
Alaska Airlines
Wed 3/45:20 pm
IDA
- STL
1 stop19h 31m
Alaska Airlines
Deal found 1/31![Alaska Airlines logo]()
$393
This Delta deal was found by Cheapflights users on 2/2. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/296:00 am
STL
- BOI
1 stop8h 07m
Delta
Sun 5/36:16 pm
BOI
- STL
1 stop5h 09m
Delta
Deal found 2/2![Delta logo]()
$281
This Delta deal was found by Cheapflights users on 2/1. 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.
Sun 3/86:29 am
STL
- BOI
1 stop8h 35m
Delta
Wed 3/115:30 am
BOI
- STL
1 stop5h 18m
Delta
Deal found 2/1![Delta logo]()
$281
This United Airlines deal was found by Cheapflights users on 2/2. 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.
Tue 3/38:41 am
STL
- IDA
1 stop5h 49m
United Airlines
Wed 3/42:40 pm
IDA
- STL
1 stop4h 46m
United Airlines
Deal found 2/2![United Airlines logo]()
$341
This Delta deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/257:15 am
STL
- GEG
1 stop7h 30m
Delta
Thu 3/262:15 pm
GEG
- STL
1 stop7h 10m
Delta
Deal found 2/1![Delta logo]()
$282
This Delta deal was found by Cheapflights users on 2/2. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/117:59 pm
STL
- GEG
1 stop5h 36m
Delta
Sat 5/166:50 am
GEG
- STL
1 stop7h 59m
Delta
Deal found 2/2![Delta logo]()
$282
This Delta deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/139:45 am
STL
- GEG
1 stop5h 25m
Delta
Wed 3/1812:35 pm
GEG
- STL
1 stop9h 23m
Delta
Deal found 2/1![Delta logo]()
$282
This United Airlines deal was found by Cheapflights users on 2/1. 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.
Wed 3/47:41 am
STL
- IDA
2 stops8h 59m
United Airlines
Tue 3/102:35 pm
IDA
- STL
1 stop7h 59m
United Airlines
Deal found 2/1![United Airlines logo]()
$453
This Delta deal was found by Cheapflights users on 2/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/52:22 pm
STL
- BOI
2 stops8h 34m
Delta
Wed 3/115:30 am
BOI
- STL
1 stop5h 18m
Delta
Deal found 2/3![Delta logo]()
$295
This United Airlines deal was found by Cheapflights users on 2/1. 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 6/279:23 am
STL
- IDA
2 stops8h 59m
United Airlines
Sat 7/42:31 pm
IDA
- STL
1 stop5h 11m
United Airlines
Deal found 2/1![United Airlines logo]()
$460
This Delta deal was found by Cheapflights users on 2/2. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/302:20 pm
STL
- JAC
1 stop5h 41m
Delta
Sat 5/21:00 pm
JAC
- STL
1 stop7h 32m
Delta
Deal found 2/2![Delta logo]()
$299
This Delta deal was found by Cheapflights users on 2/2. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/32:12 pm
STL
- JAC
1 stop5h 50m
Delta
Tue 4/75:50 pm
JAC
- STL
1 stop5h 31m
Delta
Deal found 2/2![Delta logo]()
$299
This Delta deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/257:15 am
STL
- JAC
1 stop5h 55m
Delta
Mon 3/305:50 pm
JAC
- STL
1 stop5h 31m
Delta
Deal found 2/1![Delta logo]()
$299
This Delta deal was found by Cheapflights users on 2/1. 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 3/52:22 pm
STL
- BOI
2 stops10h 23m
Delta
Tue 3/107:30 am
BOI
- STL
2 stops8h 37m
Delta
Deal found 2/1![Delta logo]()
$303
This Delta deal was found by Cheapflights users on 2/2. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/32:22 pm
STL
- JAC
1 stop5h 42m
Delta
Tue 3/101:10 pm
JAC
- STL
2 stops9h 48m
Delta
Deal found 2/2![Delta logo]()
$304
This Delta deal was found by Cheapflights users on 2/1. 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.
Mon 3/27:00 am
STL
- GEG
1 stop7h 07m
Delta
Fri 3/612:48 pm
GEG
- STL
1 stop8h 48m
Delta
Deal found 2/1![Delta logo]()
$309
This United Airlines deal was found by Cheapflights users on 2/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/34:50 pm
STL
- WYS
1 stop21h 30m
United Airlines
Tue 7/72:02 pm
WYS
- STL
1 stop5h 40m
United Airlines
Deal found 2/3![United Airlines logo]()
$755
Last-minute flights from St. Louis to IdahoDiscover last-minute flight deals from St. Louis to Idaho. Data last updated February 3, 2026 and is based on user searches.
Discover last-minute flight deals from St. Louis to Idaho. Data last updated February 3, 2026 and is based on user searches.
This Alaska Airlines deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/37:00 am
STL
- GEG
1 stop7h 29m
Alaska Airlines
Wed 3/45:40 am
GEG
- STL
1 stop6h 11m
Alaska Airlines
Deal found 2/1![Alaska Airlines logo]()
$237
This United Airlines deal was found by Cheapflights users on 2/2. 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.
Tue 3/36:25 am
STL
- BOI
2 stops8h 13m
United Airlines
Tue 3/105:31 pm
BOI
- STL
1 stop5h 03m
United Airlines
Deal found 2/2![United Airlines logo]()
$242
This United Airlines deal was found by Cheapflights users on 2/1. 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 3/38:41 am
STL
- IDA
1 stop5h 49m
United Airlines
Tue 3/105:30 pm
IDA
- STL
1 stop5h 04m
United Airlines
Deal found 2/1![United Airlines logo]()
$279
This Delta deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/47:00 am
STL
- BOI
2 stops15h 56m
Delta
Wed 3/116:15 pm
BOI
- STL
1 stop5h 06m
Delta
Deal found 2/1![Delta logo]()
$265
This Alaska Airlines deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/47:00 am
STL
- IDA
1 stop10h 43m
Alaska Airlines
Tue 3/105:20 pm
IDA
- STL
1 stop19h 31m
Alaska Airlines
Deal found 2/1![Alaska Airlines logo]()
$287
This American Airlines deal was found by Cheapflights users on 2/2. 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.
Thu 3/56:00 am
STL
- GEG
1 stop7h 44m
American Airlines
Tue 3/103:10 pm
GEG
- STL
1 stop6h 49m
American Airlines
Deal found 2/2![American Airlines logo]()
$264
This United Airlines deal was found by Cheapflights users on 2/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/52:50 pm
STL
- GEG
1 stop8h 28m
United Airlines
Tue 3/107:02 am
GEG
- STL
2 stops11h 39m
United Airlines
Deal found 2/2![United Airlines logo]()
$269
This American Airlines deal was found by Cheapflights users on 2/2. 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.
Thu 3/56:00 am
STL
- GEG
1 stop7h 44m
American Airlines
Mon 3/93:10 pm
GEG
- STL
1 stop6h 49m
American Airlines
Deal found 2/2![American Airlines logo]()
$291
This Kiwi.com deal was found by Cheapflights users on 2/1. 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 3/78:12 pm
STL
- BOI
1 stop15h 08m
Frontier
Thu 3/1212:15 pm
BOI
- STL
1 stop20h 34m
Frontier
Deal found 2/1![Frontier logo]()
$152
This Delta deal was found by Cheapflights users on 2/1. 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.
Sat 3/77:00 am
STL
- BOI
1 stop6h 09m
Delta
Wed 3/115:30 am
BOI
- STL
1 stop7h 54m
Delta
Deal found 2/1![Delta logo]()
$237
This Delta deal was found by Cheapflights users on 2/1. 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.
Sat 3/76:00 am
STL
- BOI
1 stop7h 31m
Delta
Mon 3/910:35 am
BOI
- STL
2 stops12h 46m
Delta
Deal found 2/1![Delta logo]()
$275
This Delta deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/139:45 am
STL
- GEG
1 stop5h 25m
Delta
Wed 3/1812:35 pm
GEG
- STL
1 stop9h 23m
Delta
Deal found 2/1![Delta logo]()
$282
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 February 3, 2026.
Search for one-way flight options from St. Louis to Idaho. Find affordable one-way fares based on user searches. Data last updated February 3, 2026.
This Delta deal was found by Cheapflights users on 2/2. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/296:00 am
STL
- BOI
1 stop8h 07m
Delta
Deal found 2/2![Delta logo]()
$119
This American Airlines deal was found by Cheapflights users on 2/1. 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.
Mon 3/24:13 pm
STL
- BOI
1 stop7h 09m
American Airlines
Deal found 2/1![American Airlines logo]()
$163
This Delta deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/139:45 am
STL
- GEG
1 stop5h 25m
Delta
Deal found 2/1![Delta logo]()
$164
This United Airlines deal was found by Cheapflights users on 2/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/298:54 am
STL
- BOI
2 stops12h 19m
United Airlines
Deal found 2/2![United Airlines logo]()
$164
This Delta deal was found by Cheapflights users on 2/2. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/193:59 pm
STL
- BOI
2 stops8h 56m
Delta
Deal found 2/2![Delta logo]()
$167
This Delta deal was found by Cheapflights users on 2/1. 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.
Mon 3/22:22 pm
STL
- BOI
2 stops10h 23m
Delta
Deal found 2/1![Delta logo]()
$177
This Trip.com deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 3/148:12 pm
STL
- GEG
1 stop16h 35m
Frontier
Deal found 2/1![Frontier logo]()
$184
This American Airlines deal was found by Cheapflights users on 2/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/76:00 am
STL
- BOI
1 stop9h 08m
American Airlines
Deal found 2/3![American Airlines logo]()
$184
This United Airlines deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/122:50 pm
STL
- GEG
1 stop8h 28m
United Airlines
Deal found 2/1![United Airlines logo]()
$187
This Southwest deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/235:20 pm
STL
- BOI
2 stops8h 05m
Southwest
Deal found 2/1![Southwest logo]()
$189
This Southwest deal was found by Cheapflights users on 2/2. 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.
Wed 5/205:30 am
STL
- BOI
2 stops12h 10m
Southwest
Deal found 2/2![Southwest logo]()
$195
This United Airlines deal was found by Cheapflights users on 2/1. 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 5/251:38 pm
STL
- JAC
1 stop5h 14m
United Airlines
Deal found 2/1![United Airlines logo]()
$202
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 February 3, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $152 (Kiwi.com) |
One-way from | $119 (Delta) |
Popular in | February |
Cheapest in | November |
Average price | $553 |
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 February 3, 2026.
Use the filters below to find and compare flights from St. Louis to Idaho that are best for you.
Fly from
St. Louis
Fly to
Idaho
Route
Depart
Return
Price
St. LouisSpokane
STL - GEG
STLGEG
Lambert-St Louis
Wed 5/6
5:35 pm-9:05 pm
1 stop5h 30m
Spokane
Sat 5/16
6:50 am-3:19 pm
1 stop6h 29m
$237
St. LouisSpokane
STL - GEG
STLGEG
Lambert-St Louis
Tue 3/3
7:00 am-12:29 pm
1 stop7h 29m
Spokane
Wed 3/4
5:40 am-1:51 pm
1 stop6h 11m
$237
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Tue 3/3
8:41 am-1:38 pm
1 stop5h 57m
Boise Air Term. Gowen Fld
Tue 3/10
2:40 pm-11:34 pm
1 stop7h 54m
$237
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Sat 3/7
7:00 am-12:09 pm
1 stop6h 09m
Boise Air Term. Gowen Fld
Wed 3/11
5:30 am-2:24 pm
1 stop7h 54m
$237
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Sat 3/7
3:40 pm-8:55 pm
1 stop6h 15m
Boise Air Term. Gowen Fld
Tue 3/10
6:00 am-1:31 pm
1 stop6h 31m
$237
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Wed 3/4
7:00 am-9:56 pm
2 stops15h 56m
Boise Air Term. Gowen Fld
Wed 3/11
6:15 pm-12:21 am
1 stop5h 06m
$265
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Sat 3/7
8:12 pm-10:20 am
1 stop15h 08m
Boise Air Term. Gowen Fld
Thu 3/12
12:15 pm-1:34 pm
2 stops24h 19m
$273
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Wed 4/1
2:40 pm-9:22 pm
1 stop7h 42m
Boise Air Term. Gowen Fld
Mon 4/6
7:03 pm-5:50 am
1 stop9h 47m
$281
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Sun 4/5
6:12 pm-11:59 pm
1 stop6h 47m
Boise Air Term. Gowen Fld
Sat 4/11
6:00 am-2:43 pm
1 stop7h 43m
$281
St. LouisBoise
STL - BOI
STLBOI
Lambert-St Louis
Wed 4/29
6:00 am-1:07 pm
1 stop8h 07m
Boise Air Term. Gowen Fld
Sun 5/3
6:16 pm-12:25 am
1 stop5h 09m
$281
Showing 1-10 of 55 results
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-GEG
STL-IDA
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-BOI
STL-GEG
STL-IDA
STL-JAC
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 January is currently the most expensive (average of $359). 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 February 3, 2026.
Peruse reviews from past customers who have flown with Southwest, Delta, and United 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.
Boarding
8.1
Crew
8.6
Entertainment
7.5
Overall
8.0
Comfort
8.0
Food
7.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Boarding
8.1
Crew
8.6
Entertainment
7.5
Overall
8.0
Comfort
8.0
Food
7.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Boarding
8.1
Crew
8.6
Entertainment
7.5
Overall
8.0
Comfort
8.0
Food
7.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Boarding
8.1
Crew
8.6
Entertainment
7.5
Overall
8.0
Comfort
8.0
Food
7.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Boarding
8.1
Crew
8.6
Entertainment
7.5
Overall
8.0
Comfort
8.0
Food
7.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
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 February 3, 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 February 3, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$163 | Average$383 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$186 | Average$366 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$290 | Average$486 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$296 | Average$421 | FlexibilityNo cancel fee | On-time63% |