$80+ Cheap flights from Idaho to St. Louis (STL)
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 4/16. Fares are subject to change and may not be available on all flights or dates of travel.
BOI — STL
Apr 23 — Apr 301
Round-trip
1 adult, Economy
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Find cheap flights from Idaho to St. Louis 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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Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheap flight deals from Idaho to St. Louis
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Cheapest flights from Idaho to St. LouisExplore the most affordable flight options available from Idaho to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 24, 2026.
Explore the most affordable flight options available from Idaho to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 24, 2026.
This Southwest deal was found by Cheapflights users on 3/24. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/54:05 pm
BOI
- STL
1 stop6h 10m
Southwest
Wed 5/66:30 pm
STL
- BOI
1 stop6h 55m
Southwest
Deal found 3/24![Southwest logo]()
$263
This Expedia deal was found by Cheapflights users on 3/24. 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 4/2311:44 am
GEG
- STL
1 stop5h 37m
Multiple Airlines
Thu 4/304:46 pm
STL
- GEG
1 stop9h 09m
Multiple Airlines
Deal found 3/24![Multiple Airlines logo]()
$288
This American Airlines deal was found by Cheapflights users on 3/23. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/142:14 pm
BOI
- STL
1 stop8h 45m
American Airlines
Thu 4/235:51 am
STL
- BOI
1 stop7h 58m
American Airlines
Deal found 3/23![American Airlines logo]()
$290
This Kiwi.com deal was found by Cheapflights users on 3/20. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/71:22 pm
BOI
- STL
1 stop29h 01m
Frontier
Mon 5/118:08 pm
STL
- BOI
1 stop17h 19m
Frontier
Deal found 3/20![Frontier logo]()
$305
This Alaska Airlines deal was found by Cheapflights users on 3/19. 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 4/142:22 pm
BOI
- STL
1 stop8h 37m
Alaska Airlines
Wed 4/157:00 am
STL
- BOI
1 stop9h 29m
Alaska Airlines
Deal found 3/19![Alaska Airlines logo]()
$317
This Southwest deal was found by Cheapflights users on 3/20. 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.
Sat 4/181:45 pm
GEG
- STL
1 stop7h 15m
Southwest
Sat 4/257:00 am
STL
- GEG
1 stop7h 25m
Southwest
Deal found 3/20![Southwest logo]()
$317
This Expedia deal was found by Cheapflights users on 3/19. 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.
Thu 4/1611:53 am
BOI
- STL
1 stop6h 28m
Multiple Airlines
Thu 4/237:00 am
STL
- BOI
1 stop7h 52m
Multiple Airlines
Deal found 3/19![Multiple Airlines logo]()
$319
This Alaska Airlines deal was found by Cheapflights users on 3/22. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/204:03 pm
IDA
- STL
1 stop6h 56m
Alaska Airlines
Sat 10/246:41 am
STL
- IDA
1 stop9h 48m
Alaska Airlines
Deal found 3/22![Alaska Airlines logo]()
$319
This Delta deal was found by Cheapflights users on 3/23. 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 4/1410:41 am
BOI
- STL
2 stops12h 44m
Delta
Thu 4/239:26 am
STL
- BOI
1 stop6h 00m
Delta
Deal found 3/23![Delta logo]()
$325
This Alaska Airlines deal was found by Cheapflights users on 3/23. 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 5/54:38 pm
BOI
- STL
1 stop6h 21m
Alaska Airlines
Wed 5/64:46 pm
STL
- BOI
1 stop7h 16m
Alaska Airlines
Deal found 3/23![Alaska Airlines logo]()
$329
This American Airlines deal was found by Cheapflights users on 3/23. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/131:22 pm
GEG
- STL
1 stop8h 24m
American Airlines
Thu 4/165:51 am
STL
- GEG
1 stop8h 41m
American Airlines
Deal found 3/23![American Airlines logo]()
$331
This United Airlines deal was found by Cheapflights users on 3/21. 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 5/212:38 pm
SUN
- STL
1 stop5h 05m
United Airlines
Sun 5/244:48 pm
STL
- SUN
1 stop5h 38m
United Airlines
Deal found 3/21![United Airlines logo]()
$331
Best flights from Idaho to St. LouisDiscover carefully curated flight deals from Idaho to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated March 24, 2026.
Discover carefully curated flight deals from Idaho to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated March 24, 2026.
This Alaska Airlines deal was found by Cheapflights users on 3/19. 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 4/142:22 pm
BOI
- STL
1 stop8h 37m
Alaska Airlines
Wed 4/157:00 am
STL
- BOI
1 stop9h 29m
Alaska Airlines
Deal found 3/19![Alaska Airlines logo]()
$317
This Southwest deal was found by Cheapflights users on 3/20. 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.
Sat 4/185:45 am
GEG
- STL
2 stops10h 25m
Southwest
Sat 4/257:00 am
STL
- GEG
1 stop7h 25m
Southwest
Deal found 3/20![Southwest logo]()
$322
This United Airlines deal was found by Cheapflights users on 3/22. 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.
Tue 5/264:10 pm
IDA
- STL
1 stop6h 47m
United Airlines
Tue 6/29:06 am
STL
- IDA
1 stop5h 19m
United Airlines
Deal found 3/22![United Airlines logo]()
$353
This American Airlines deal was found by Cheapflights users on 3/20. 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.
Sat 4/181:25 pm
JAC
- STL
1 stop8h 34m
American Airlines
Sat 4/255:20 am
STL
- JAC
1 stop8h 20m
American Airlines
Deal found 3/20![American Airlines logo]()
$359
This Delta deal was found by Cheapflights users on 3/23. 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 4/77:20 am
JAC
- STL
1 stop4h 57m
Delta
Sat 4/117:15 am
STL
- JAC
1 stop5h 55m
Delta
Deal found 3/23![Delta logo]()
$391
This Alaska Airlines deal was found by Cheapflights users on 3/23. 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 5/54:38 pm
BOI
- STL
1 stop6h 21m
Alaska Airlines
Wed 5/64:46 pm
STL
- BOI
1 stop7h 16m
Alaska Airlines
Deal found 3/23![Alaska Airlines logo]()
$329
This United Airlines deal was found by Cheapflights users on 3/20. 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.
Sat 4/42:35 pm
JAC
- STL
1 stop5h 19m
United Airlines
Wed 4/89:10 am
STL
- JAC
2 stops12h 43m
United Airlines
Deal found 3/20![United Airlines logo]()
$364
This Alaska Airlines deal was found by Cheapflights users on 3/19. 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.
Sat 5/26:00 am
GEG
- STL
1 stop7h 50m
Alaska Airlines
Tue 5/57:00 am
STL
- GEG
1 stop8h 23m
Alaska Airlines
Deal found 3/19![Alaska Airlines logo]()
$357
This Southwest deal was found by Cheapflights users on 3/22. 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 6/32:00 pm
BOI
- STL
1 stop7h 00m
Southwest
Sun 6/74:45 pm
STL
- BOI
2 stops9h 35m
Southwest
Deal found 3/22![Southwest logo]()
$401
This Delta deal was found by Cheapflights users on 3/22. 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.
Mon 4/66:55 pm
IDA
- STL
1 stop4h 26m
Delta
Fri 4/106:12 pm
STL
- IDA
1 stop5h 04m
Delta
Deal found 3/22![Delta logo]()
$434
This United Airlines deal was found by Cheapflights users on 3/20. 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.
Sat 4/182:35 pm
JAC
- STL
1 stop5h 19m
United Airlines
Sat 4/258:30 am
STL
- JAC
2 stops13h 23m
United Airlines
Deal found 3/20![United Airlines logo]()
$396
This Alaska Airlines deal was found by Cheapflights users on 3/20. 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 5/264:03 pm
IDA
- STL
1 stop23h 34m
Alaska Airlines
Fri 5/295:33 pm
STL
- IDA
1 stop20h 44m
Alaska Airlines
Deal found 3/20![Alaska Airlines logo]()
$389
This Delta deal was found by Cheapflights users on 3/20. 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.
Sat 4/187:20 am
JAC
- STL
2 stops8h 30m
Delta
Sat 4/256:00 am
STL
- JAC
2 stops11h 13m
Delta
Deal found 3/20![Delta logo]()
$435
This United Airlines deal was found by Cheapflights users on 3/22. 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.
Thu 6/47:30 am
JAC
- STL
1 stop7h 16m
United Airlines
Mon 6/81:38 pm
STL
- JAC
1 stop5h 16m
United Airlines
Deal found 3/22![United Airlines logo]()
$408
This Southwest deal was found by Cheapflights users on 3/24. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/254:25 pm
BOI
- STL
1 stop6h 30m
Southwest
Mon 6/296:40 pm
STL
- BOI
2 stops8h 05m
Southwest
Deal found 3/24![Southwest logo]()
$450
This Delta deal was found by Cheapflights users on 3/19. 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.
Tue 4/2111:35 pm
BOI
- STL
1 stop7h 55m
Delta
Tue 4/282:20 pm
STL
- BOI
2 stops9h 04m
Delta
Deal found 3/19![Delta logo]()
$436
This Southwest deal was found by Cheapflights users on 3/22. 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 5/155:50 am
GEG
- STL
2 stops13h 05m
Southwest
Wed 5/206:35 am
STL
- GEG
2 stops8h 30m
Southwest
Deal found 3/22![Southwest logo]()
$452
This United Airlines deal was found by Cheapflights users on 3/19. 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 5/25:00 am
GEG
- STL
1 stop7h 28m
United Airlines
Tue 5/59:21 am
STL
- GEG
2 stops13h 55m
United Airlines
Deal found 3/19![United Airlines logo]()
$412
This Southwest deal was found by Cheapflights users on 3/23. 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 8/46:15 am
GEG
- STL
1 stop6h 50m
Southwest
Tue 8/46:30 pm
STL
- GEG
1 stop5h 55m
Southwest
Deal found 3/23![Southwest logo]()
$457
This Delta deal was found by Cheapflights users on 3/19. 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.
Thu 4/167:24 am
BOI
- STL
2 stops9h 02m
Delta
Thu 4/239:26 am
STL
- BOI
1 stop6h 00m
Delta
Deal found 3/19![Delta logo]()
$461
This United Airlines deal was found by Cheapflights users on 3/19. 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 4/147:11 am
BOI
- STL
2 stops12h 43m
United Airlines
Wed 4/158:54 am
STL
- BOI
2 stops12h 19m
United Airlines
Deal found 3/19![United Airlines logo]()
$427
This Delta deal was found by Cheapflights users on 3/22. 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.
Tue 5/127:23 pm
GEG
- STL
2 stops11h 23m
Delta
Sat 5/235:00 pm
STL
- GEG
1 stop7h 29m
Delta
Deal found 3/22![Delta logo]()
$461
This United Airlines deal was found by Cheapflights users on 3/23. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/52:26 pm
BOI
- STL
1 stop5h 17m
United Airlines
Wed 5/68:46 am
STL
- BOI
2 stops14h 30m
United Airlines
Deal found 3/23![United Airlines logo]()
$429
This Delta deal was found by Cheapflights users on 3/22. 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.
Fri 4/247:38 pm
GEG
- STL
2 stops12h 10m
Delta
Mon 4/276:00 am
STL
- GEG
1 stop7h 41m
Delta
Deal found 3/22![Delta logo]()
$461
This Alaska Airlines deal was found by Cheapflights users on 3/24. 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.
Thu 4/96:00 am
IDA
- STL
1 stop8h 20m
Alaska Airlines
Fri 4/174:20 pm
STL
- IDA
1 stop7h 32m
Alaska Airlines
Deal found 3/24![Alaska Airlines logo]()
$559
This United Airlines deal was found by Cheapflights users on 3/23. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/265:54 pm
IDA
- STL
1 stop5h 03m
United Airlines
Fri 5/295:10 am
STL
- IDA
1 stop5h 40m
United Airlines
Deal found 3/23![United Airlines logo]()
$429
This Delta deal was found by Cheapflights users on 3/24. 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.
Tue 5/2611:30 am
IDA
- STL
1 stop6h 33m
Delta
Wed 6/36:45 am
STL
- IDA
2 stops12h 29m
Delta
Deal found 3/24![Delta logo]()
$474
This United Airlines deal was found by Cheapflights users on 3/24. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/95:00 am
GEG
- STL
1 stop7h 28m
United Airlines
Sat 5/239:23 am
STL
- GEG
2 stops13h 07m
United Airlines
Deal found 3/24![United Airlines logo]()
$431
This United Airlines deal was found by Cheapflights users on 3/20. 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 7/94:23 pm
JAC
- STL
1 stop6h 34m
United Airlines
Fri 7/171:13 pm
STL
- JAC
1 stop6h 29m
United Airlines
Deal found 3/20![United Airlines logo]()
$449
This Delta deal was found by Cheapflights users on 3/23. 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 5/2611:30 am
IDA
- STL
1 stop6h 33m
Delta
Fri 5/291:59 pm
STL
- IDA
2 stops9h 43m
Delta
Deal found 3/23![Delta logo]()
$494
Last-minute flights from Idaho to St. LouisDiscover last-minute flight deals from Idaho to St. Louis. Data last updated March 24, 2026 and is based on user searches.
Discover last-minute flight deals from Idaho to St. Louis. Data last updated March 24, 2026 and is based on user searches.
This American Airlines deal was found by Cheapflights users on 3/20. 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.
Sat 4/41:44 pm
JAC
- STL
1 stop6h 27m
American Airlines
Wed 4/85:20 am
STL
- JAC
1 stop8h 21m
American Airlines
Deal found 3/20![American Airlines logo]()
$359
This United Airlines deal was found by Cheapflights users on 3/20. 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.
Sat 4/42:35 pm
JAC
- STL
1 stop5h 19m
United Airlines
Wed 4/89:10 am
STL
- JAC
2 stops12h 43m
United Airlines
Deal found 3/20![United Airlines logo]()
$364
This Delta deal was found by Cheapflights users on 3/23. 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 4/77:20 am
JAC
- STL
1 stop4h 57m
Delta
Sat 4/117:15 am
STL
- JAC
1 stop5h 55m
Delta
Deal found 3/23![Delta logo]()
$391
This American Airlines deal was found by Cheapflights users on 3/23. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/131:22 pm
GEG
- STL
1 stop8h 24m
American Airlines
Thu 4/165:51 am
STL
- GEG
1 stop8h 41m
American Airlines
Deal found 3/23![American Airlines logo]()
$331
This Delta deal was found by Cheapflights users on 3/23. 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.
Mon 4/1310:40 pm
GEG
- STL
1 stop9h 54m
Delta
Thu 4/162:20 pm
STL
- GEG
2 stops10h 55m
Delta
Deal found 3/23![Delta logo]()
$398
This American Airlines deal was found by Cheapflights users on 3/23. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/142:14 pm
BOI
- STL
1 stop8h 45m
American Airlines
Thu 4/235:51 am
STL
- BOI
1 stop7h 58m
American Airlines
Deal found 3/23![American Airlines logo]()
$290
This Alaska Airlines deal was found by Cheapflights users on 3/19. 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 4/142:22 pm
BOI
- STL
1 stop8h 37m
Alaska Airlines
Wed 4/157:00 am
STL
- BOI
1 stop9h 29m
Alaska Airlines
Deal found 3/19![Alaska Airlines logo]()
$317
This Delta deal was found by Cheapflights users on 3/23. 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 4/1410:41 am
BOI
- STL
2 stops12h 44m
Delta
Thu 4/239:26 am
STL
- BOI
1 stop6h 00m
Delta
Deal found 3/23![Delta logo]()
$325
This Expedia deal was found by Cheapflights users on 3/19. 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.
Thu 4/1611:53 am
BOI
- STL
1 stop6h 28m
Multiple Airlines
Thu 4/237:00 am
STL
- BOI
1 stop7h 52m
Multiple Airlines
Deal found 3/19![Multiple Airlines logo]()
$319
This Southwest deal was found by Cheapflights users on 3/20. 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.
Sat 4/181:45 pm
GEG
- STL
1 stop7h 15m
Southwest
Sat 4/257:00 am
STL
- GEG
1 stop7h 25m
Southwest
Deal found 3/20![Southwest logo]()
$317
This Southwest deal was found by Cheapflights users on 3/23. 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.
Mon 4/202:50 pm
GEG
- STL
1 stop7h 00m
Southwest
Mon 4/276:00 pm
STL
- GEG
1 stop8h 30m
Southwest
Deal found 3/23![Southwest logo]()
$343
This Expedia deal was found by Cheapflights users on 3/24. 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 4/2311:44 am
GEG
- STL
1 stop5h 37m
Multiple Airlines
Thu 4/304:46 pm
STL
- GEG
1 stop9h 09m
Multiple Airlines
Deal found 3/24![Multiple Airlines logo]()
$288
One-way flights from Idaho to St. LouisSearch for one-way flight options from Idaho to St. Louis. Find affordable one-way fares based on user searches. Data last updated March 24, 2026.
Search for one-way flight options from Idaho to St. Louis. Find affordable one-way fares based on user searches. Data last updated March 24, 2026.
This Priceline deal was found by Cheapflights users on 3/24. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/1611:44 am
GEG
- STL
1 stop5h 37m
Frontier
Deal found 3/24![Frontier logo]()
$80
This Frontier deal was found by Cheapflights users on 3/21. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/3011:44 am
GEG
- STL
1 stop5h 37m
Frontier
Deal found 3/21![Frontier logo]()
$105
This CheapOair deal was found by Cheapflights users on 3/21. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/912:03 pm
BOI
- STL
1 stop20h 45m
Frontier
Deal found 3/21![Frontier logo]()
$117
This Delta deal was found by Cheapflights users on 3/24. 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 4/1510:45 am
BOI
- STL
1 stop5h 41m
Delta
Deal found 3/24![Delta logo]()
$132
This American Airlines deal was found by Cheapflights users on 3/22. 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.
Wed 4/152:14 pm
BOI
- STL
1 stop8h 45m
American Airlines
Deal found 3/22![American Airlines logo]()
$159
This American Airlines deal was found by Cheapflights users on 3/21. 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.
Wed 4/291:22 pm
GEG
- STL
1 stop6h 55m
American Airlines
Deal found 3/21![American Airlines logo]()
$159
This Southwest deal was found by Cheapflights users on 3/23. 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.
Sat 5/910:45 am
GEG
- STL
2 stops7h 40m
Southwest
Deal found 3/23![Southwest logo]()
$164
This Delta deal was found by Cheapflights users on 3/20. 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 4/910:40 pm
GEG
- STL
1 stop8h 25m
Delta
Deal found 3/20![Delta logo]()
$166
This Delta deal was found by Cheapflights users on 3/20. 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.
Sat 4/111:40 pm
BOI
- STL
1 stop9h 18m
Delta
Deal found 3/20![Delta logo]()
$169
This Kiwi.com deal was found by Cheapflights users on 3/24. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/169:19 pm
GEG
- STL
2 stops44h 13m
Multiple Airlines
Deal found 3/24![Multiple Airlines logo]()
$172
This American Airlines deal was found by Cheapflights users on 3/19. 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.
Sat 4/111:53 pm
BOI
- STL
1 stop8h 06m
American Airlines
Deal found 3/19![American Airlines logo]()
$178
This Southwest deal was found by Cheapflights users on 3/23. 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.
Thu 5/72:50 pm
GEG
- STL
1 stop7h 00m
Southwest
Deal found 3/23![Southwest logo]()
$178
Find flight deals from Idaho to St. Louis
Keep the following information in mind while searching for Idaho to St. Louis flight deals. Data was last updated March 24, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $263 (Southwest) |
One-way from | $105 (Frontier) |
Popular in | November |
Cheapest in | September |
Average price | $471 |
Cheapflights Fare Finder
Customize your flight search to find flights from Idaho to St. Louis 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 24, 2026.
Use the filters below to find and compare flights from Idaho to St. Louis that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
BoiseSt. Louis
BOI - STL
BOISTL
Boise Air Term. Gowen Fld
Tue 4/14
2:22 pm-11:59 pm
1 stop8h 37m
Lambert-St Louis
Wed 4/15
7:00 am-3:29 pm
1 stop9h 29m
$317
SpokaneSt. Louis
GEG - STL
GEGSTL
Spokane
Sat 4/18
5:45 am-6:10 pm
2 stops10h 25m
Lambert-St Louis
Sat 4/25
7:00 am-12:25 pm
1 stop7h 25m
$322
BoiseSt. Louis
BOI - STL
BOISTL
Boise Air Term. Gowen Fld
Tue 5/5
4:38 pm-11:59 pm
1 stop6h 21m
Lambert-St Louis
Wed 5/6
4:46 pm-11:02 pm
1 stop7h 16m
$329
Idaho FallsSt. Louis
IDA - STL
IDASTL
Idaho Falls Fanning Field
Tue 5/26
4:10 pm-11:57 pm
1 stop6h 47m
Lambert-St Louis
Tue 6/2
9:06 am-1:25 pm
1 stop5h 19m
$353
SpokaneSt. Louis
GEG - STL
GEGSTL
Spokane
Sat 5/2
6:00 am-3:50 pm
1 stop7h 50m
Lambert-St Louis
Tue 5/5
7:00 am-1:23 pm
1 stop8h 23m
$357
JacksonSt. Louis
JAC - STL
JACSTL
Jackson Hole
Sat 4/18
1:25 pm-10:59 pm
1 stop8h 34m
Lambert-St Louis
Sat 4/25
5:20 am-12:40 pm
1 stop8h 20m
$359
JacksonSt. Louis
JAC - STL
JACSTL
Jackson Hole
Sat 4/4
2:35 pm-8:54 pm
1 stop5h 19m
Lambert-St Louis
Wed 4/8
9:10 am-8:53 pm
2 stops12h 43m
$364
Idaho FallsSt. Louis
IDA - STL
IDASTL
Idaho Falls Fanning Field
Tue 5/26
4:03 pm-4:37 pm
1 stop23h 34m
Lambert-St Louis
Fri 5/29
5:33 pm-1:17 pm
1 stop20h 44m
$389
JacksonSt. Louis
JAC - STL
JACSTL
Jackson Hole
Tue 4/7
7:20 am-1:17 pm
1 stop4h 57m
Lambert-St Louis
Sat 4/11
7:15 am-12:10 pm
1 stop5h 55m
$391
JacksonSt. Louis
JAC - STL
JACSTL
Jackson Hole
Sat 4/18
2:35 pm-8:54 pm
1 stop5h 19m
Lambert-St Louis
Sat 4/25
8:30 am-8:53 pm
2 stops13h 23m
$396
Showing 1-10 of 59 resultsSorted by cheapest first
Best time to book a flight from Idaho to St. Louis
Have a flexible travel schedule? Discover the best time to fly to St. Louis from Idaho with our price prediction graph.
GEG-STL
BOI-STL
JAC-STL
IDA-STL
SUN-STL
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 Idaho to St. Louis
USID-STL
GEG-STL
BOI-STL
JAC-STL
IDA-STL
What is the cheapest month to book a flight from Idaho to St. Louis?
Currently, April is the cheapest month in which you can book a flight from Idaho to St. Louis (average of $113). Flying from Idaho to St. Louis in February is currently the most expensive (average of $376). 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.
Related info for your journey
Find useful and relevant information for your journey from Idaho to St. Louis. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
Traveling to a place near St. Louis?
Book flights to St. Louis if you plan to visit one of these locationsEdwardsville
O'Fallon
Fenton
Swansea
Fairview Heights
Maryland Heights
Collinsville
Eureka
Wentzville
Glencoe
Chesterfield
Alton
Farmington
Festus
Browse thousands of different options on Cheapflights for your next trip
Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.
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St. Louis flight routes
Top destinations
Alternative routes for Idaho to St. Louis
See prices for flight routes from nearby airports that may be better suited for you.
Complete your trip
Complete your trip to St. Louis by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Idaho to St. Louis by cabin class
Find flights from Idaho to St. Louis, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Idaho and St. Louis flights
Browse other Idaho and St. Louis flight options. Last updated on March 24, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Other flights to St. Louis
Explore flights to St. Louis departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on March 24, 2026.
Idaho to St. Louis flights
Consider these flights traveling from Idaho to St. Louis.
Top 5 airlines flying from Idaho to St. Louis
Discover the top 5 airlines that operate flights from Idaho to St. Louis. 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 24, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$185 | Average$436 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$278 | Average$428 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$278 | Average$378 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$281 | Average$470 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$283 | Average$456 | FlexibilityNo cancel fee | On-time69% |