$150+ Cheap flights from Idaho Falls to St. Louis (IDA - 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 5/20. Fares are subject to change and may not be available on all flights or dates of travel.
IDA — STL
Apr 11 — Apr 181
Round-trip
1 adult, Economy
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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 Idaho Falls to St. LouisExplore the most affordable flight options available from Idaho Falls to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 12, 2026.
Explore the most affordable flight options available from Idaho Falls to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 12, 2026.
This Delta deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 4/41:10 pm
IDA
- STL
1 stop7h 21m
Delta
Sat 4/117:15 am
STL
- IDA
1 stop6h 12m
Delta
Deal found 3/8![Delta logo]()
$299
This Delta deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 3/296:55 pm
IDA
- STL
2 stops13h 10m
Delta
Tue 4/76:12 pm
STL
- IDA
1 stop5h 04m
Delta
Deal found 3/8![Delta logo]()
$304
This Delta deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 4/76:55 pm
IDA
- STL
1 stop4h 26m
Delta
Sat 4/117:15 am
STL
- IDA
1 stop6h 12m
Delta
Deal found 3/8![Delta logo]()
$314
This Alaska Airlines deal was found by Cheapflights users on 3/9. Clicking the “Pick Dates” 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 10/246:15 am
IDA
- STL
1 stop7h 11m
Alaska Airlines
Tue 10/273:24 pm
STL
- IDA
1 stop8h 15m
Alaska Airlines
Deal found 3/9![Alaska Airlines logo]()
$319
This Delta deal was found by Cheapflights users on 3/10. Clicking the “Pick Dates” 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 4/185:47 am
IDA
- STL
2 stops10h 03m
Delta
Wed 4/226:45 pm
STL
- IDA
1 stop4h 55m
Delta
Deal found 3/10![Delta logo]()
$324
This Delta deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 4/255:47 am
IDA
- STL
2 stops10h 03m
Delta
Sun 5/36:45 pm
STL
- IDA
1 stop4h 55m
Delta
Deal found 3/8![Delta logo]()
$334
This Kiwi.com deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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.
Mon 4/610:06 pm
IDA
- STL
2 stops34h 42m
Multiple Airlines
Thu 4/169:55 pm
STL
- IDA
1 stop18h 32m
Multiple Airlines
Deal found 3/8![Multiple Airlines logo]()
$336
This Delta deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 4/215:47 am
IDA
- STL
1 stop6h 36m
Delta
Sat 4/255:00 pm
STL
- IDA
1 stop6h 40m
Delta
Deal found 3/8![Delta logo]()
$345
This Delta deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 3/266:55 pm
IDA
- STL
1 stop4h 26m
Delta
Fri 4/32:12 pm
STL
- IDA
1 stop5h 03m
Delta
Deal found 3/8![Delta logo]()
$349
This Delta deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 4/46:55 pm
IDA
- STL
2 stops12h 52m
Delta
Tue 4/146:45 pm
STL
- IDA
1 stop4h 55m
Delta
Deal found 3/8![Delta logo]()
$354
This Delta deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 3/311:10 pm
IDA
- STL
2 stops9h 48m
Delta
Tue 4/712:28 pm
STL
- IDA
2 stops10h 48m
Delta
Deal found 3/8![Delta logo]()
$355
Best flights from Idaho Falls to St. LouisDiscover carefully curated flight deals from Idaho Falls to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated March 12, 2026.
Discover carefully curated flight deals from Idaho Falls to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated March 12, 2026.
This United Airlines deal was found by Cheapflights users on 3/11. Clicking the “Pick Dates” 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 4/32:30 pm
IDA
- STL
1 stop5h 24m
United Airlines
Sat 8/295:10 am
STL
- IDA
1 stop5h 43m
United Airlines
Deal found 3/11![United Airlines logo]()
$319
This Delta deal was found by Cheapflights users on 3/10. Clicking the “Pick Dates” 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 4/181:09 pm
IDA
- STL
1 stop7h 22m
Delta
Wed 4/226:45 pm
STL
- IDA
1 stop4h 55m
Delta
Deal found 3/10![Delta logo]()
$369
This American 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/291:43 pm
IDA
- STL
1 stop8h 16m
American Airlines
Fri 5/85:20 am
STL
- IDA
1 stop8h 53m
American Airlines
Deal found 3/12![American Airlines logo]()
$475
This Delta deal was found by Cheapflights users on 3/7. Clicking the “Pick Dates” 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 4/11:10 pm
IDA
- STL
2 stops9h 48m
Delta
Sun 4/52:12 pm
STL
- IDA
1 stop5h 03m
Delta
Deal found 3/7![Delta logo]()
$410
This Delta deal was found by Cheapflights users on 3/11. Clicking the “Pick Dates” 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 4/265:47 am
IDA
- STL
1 stop6h 36m
Delta
Fri 5/16:45 pm
STL
- IDA
1 stop4h 55m
Delta
Deal found 3/11![Delta logo]()
$447
This United Airlines deal was found by Cheapflights users on 3/7. Clicking the “Pick Dates” 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 4/16:45 am
IDA
- STL
2 stops16h 12m
United Airlines
Sun 4/57:45 am
STL
- IDA
2 stops8h 54m
United Airlines
Deal found 3/7![United Airlines logo]()
$500
This American Airlines deal was found by Cheapflights users on 3/10. Clicking the “Pick Dates” 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 4/187:48 am
IDA
- STL
2 stops14h 58m
American Airlines
Wed 4/228:54 am
STL
- IDA
2 stops15h 45m
American Airlines
Deal found 3/10![American Airlines logo]()
$559
This Delta deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 5/46:58 pm
IDA
- STL
2 stops12h 32m
Delta
Fri 5/82:27 pm
STL
- IDA
1 stop21h 20m
Delta
Deal found 3/8![Delta logo]()
$518
This United Airlines deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 4/205:20 pm
IDA
- STL
2 stops14h 05m
United Airlines
Tue 4/284:30 pm
STL
- IDA
1 stop5h 34m
United Airlines
Deal found 3/8![United Airlines logo]()
$575
This United Airlines deal was found by Cheapflights users on 3/9. Clicking the “Pick Dates” 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 4/2910:40 am
IDA
- STL
2 stops12h 17m
United Airlines
Fri 5/87:45 am
STL
- IDA
2 stops8h 58m
United Airlines
Deal found 3/9![United Airlines logo]()
$646
Last-minute flights from Idaho Falls to St. LouisDiscover last-minute flight deals from Idaho Falls to St. Louis. Data last updated March 12, 2026 and is based on user searches.
Discover last-minute flight deals from Idaho Falls to St. Louis. Data last updated March 12, 2026 and is based on user searches.
This Delta deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 3/266:55 pm
IDA
- STL
1 stop4h 26m
Delta
Fri 4/32:12 pm
STL
- IDA
1 stop5h 03m
Delta
Deal found 3/8![Delta logo]()
$349
This Delta deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 3/296:55 pm
IDA
- STL
2 stops13h 10m
Delta
Tue 4/76:12 pm
STL
- IDA
1 stop5h 04m
Delta
Deal found 3/8![Delta logo]()
$304
This Delta deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 3/311:10 pm
IDA
- STL
2 stops9h 48m
Delta
Tue 4/712:28 pm
STL
- IDA
2 stops10h 48m
Delta
Deal found 3/8![Delta logo]()
$355
This Delta deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 4/41:10 pm
IDA
- STL
1 stop7h 21m
Delta
Sat 4/117:15 am
STL
- IDA
1 stop6h 12m
Delta
Deal found 3/8![Delta logo]()
$299
This Delta deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 4/46:55 pm
IDA
- STL
2 stops12h 52m
Delta
Tue 4/146:45 pm
STL
- IDA
1 stop4h 55m
Delta
Deal found 3/8![Delta logo]()
$354
This Kiwi.com deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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.
Mon 4/610:06 pm
IDA
- STL
2 stops34h 42m
Multiple Airlines
Thu 4/169:55 pm
STL
- IDA
1 stop18h 32m
Multiple Airlines
Deal found 3/8![Multiple Airlines logo]()
$336
This Delta deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 4/76:55 pm
IDA
- STL
1 stop4h 26m
Delta
Sat 4/117:15 am
STL
- IDA
1 stop6h 12m
Delta
Deal found 3/8![Delta logo]()
$314
This Delta deal was found by Cheapflights users on 3/10. Clicking the “Pick Dates” 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 4/185:47 am
IDA
- STL
2 stops10h 03m
Delta
Wed 4/226:45 pm
STL
- IDA
1 stop4h 55m
Delta
Deal found 3/10![Delta logo]()
$324
This Delta deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 4/215:47 am
IDA
- STL
1 stop6h 36m
Delta
Sat 4/255:00 pm
STL
- IDA
1 stop6h 40m
Delta
Deal found 3/8![Delta logo]()
$345
This Delta deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 4/255:47 am
IDA
- STL
2 stops10h 03m
Delta
Tue 5/56:45 pm
STL
- IDA
1 stop4h 55m
Delta
Deal found 3/8![Delta logo]()
$319
This Delta deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 4/255:47 am
IDA
- STL
2 stops10h 03m
Delta
Sun 5/36:45 pm
STL
- IDA
1 stop4h 55m
Delta
Deal found 3/8![Delta logo]()
$334
One-way flights from Idaho Falls to St. LouisSearch for one-way flight options from Idaho Falls to St. Louis. Find affordable one-way fares based on user searches. Data last updated March 12, 2026.
Search for one-way flight options from Idaho Falls to St. Louis. Find affordable one-way fares based on user searches. Data last updated March 12, 2026.
This Delta deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 4/41:10 pm
IDA
- STL
1 stop7h 21m
Delta
Deal found 3/8![Delta logo]()
$150
This Expedia deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 6/44:03 pm
IDA
- STL
1 stop23h 34m
Alaska Airlines
Deal found 3/8![Alaska Airlines logo]()
$155
This Delta deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 4/76:55 pm
IDA
- STL
1 stop4h 26m
Delta
Deal found 3/8![Delta logo]()
$165
This American Airlines deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 5/2112:44 pm
IDA
- STL
1 stop5h 43m
American Airlines
Deal found 3/8![American Airlines logo]()
$185
This United Airlines deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/224:10 pm
IDA
- STL
1 stop6h 47m
United Airlines
Deal found 3/8![United Airlines logo]()
$190
This Kiwi.com deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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.
Mon 5/1810:21 pm
IDA
- STL
3 stops58h 16m
Multiple Airlines
Deal found 3/8![Multiple Airlines logo]()
$200
This Delta deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 5/196:00 am
IDA
- STL
2 stops9h 46m
Delta
Deal found 3/8![Delta logo]()
$201
This United Airlines deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 5/2310:35 am
IDA
- STL
2 stops11h 09m
United Airlines
Deal found 3/8![United Airlines logo]()
$210
This Alaska Airlines deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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.
Mon 5/181:54 pm
IDA
- STL
1 stop9h 00m
Alaska Airlines
Deal found 3/8![Alaska Airlines logo]()
$220
This Alaska Airlines deal was found by Cheapflights users on 3/8. Clicking the “Pick Dates” 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 5/204:03 pm
IDA
- STL
2 stops22h 13m
Alaska Airlines
Deal found 3/8![Alaska Airlines logo]()
$228
Find flight deals from Idaho Falls to St. Louis
Discover tips and strategies to find the most affordable flight options for your journey from Idaho Falls (IDA) to St. Louis (STL). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated March 12, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $299 (Delta) |
One-way from | $150 (Delta) |
Popular in | January |
Cheapest in | April |
Average price | $645 |
Cheapflights Fare Finder
Customize your flight search to find flights from Idaho Falls 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 12, 2026.
Use the filters below to find and compare flights from Idaho Falls to St. Louis that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
Quickest round-trip
Idaho FallsSt. Louis
IDA - STL
IDASTL
Idaho Falls Fanning Field
Fri 4/3
2:30 pm-8:54 pm
1 stop5h 24m
Lambert-St Louis
Sat 8/29
5:10 am-9:53 am
1 stop5h 43m
$319
Idaho FallsSt. Louis
IDA - STL
IDASTL
Idaho Falls Fanning Field
Sat 4/18
1:09 pm-9:31 pm
1 stop7h 22m
Lambert-St Louis
Wed 4/22
6:45 pm-10:40 pm
1 stop4h 55m
$369
Idaho FallsSt. Louis
IDA - STL
IDASTL
Idaho Falls Fanning Field
Wed 4/1
1:10 pm-11:58 pm
2 stops9h 48m
Lambert-St Louis
Sun 4/5
2:12 pm-6:15 pm
1 stop5h 03m
$410
Idaho FallsSt. Louis
IDA - STL
IDASTL
Idaho Falls Fanning Field
Sun 4/26
5:47 am-1:23 pm
1 stop6h 36m
Lambert-St Louis
Fri 5/1
6:45 pm-10:40 pm
1 stop4h 55m
$447
Idaho FallsSt. Louis
IDA - STL
IDASTL
Idaho Falls Fanning Field
Wed 4/29
1:43 pm-10:59 pm
1 stop8h 16m
Lambert-St Louis
Fri 5/8
5:20 am-1:13 pm
1 stop8h 53m
$475
Idaho FallsSt. Louis
IDA - STL
IDASTL
Idaho Falls Fanning Field
Wed 4/1
6:45 am-11:57 pm
2 stops16h 12m
Lambert-St Louis
Sun 4/5
7:45 am-3:39 pm
2 stops8h 54m
$500
Idaho FallsSt. Louis
IDA - STL
IDASTL
Idaho Falls Fanning Field
Mon 5/4
6:58 pm-8:30 am
2 stops12h 32m
Lambert-St Louis
Fri 5/8
2:27 pm-10:47 am
1 stop21h 20m
$518
Idaho FallsSt. Louis
IDA - STL
IDASTL
Idaho Falls Fanning Field
Sat 4/18
7:48 am-11:46 pm
2 stops14h 58m
Lambert-St Louis
Wed 4/22
8:54 am-11:39 pm
2 stops15h 45m
$559
Idaho FallsSt. Louis
IDA - STL
IDASTL
Idaho Falls Fanning Field
Mon 4/20
5:20 pm-8:25 am
2 stops14h 05m
Lambert-St Louis
Tue 4/28
4:30 pm-9:04 pm
1 stop5h 34m
$575
Idaho FallsSt. Louis
IDA - STL
IDASTL
Idaho Falls Fanning Field
Wed 4/29
10:40 am-11:57 pm
2 stops12h 17m
Lambert-St Louis
Fri 5/8
7:45 am-3:43 pm
2 stops8h 58m
$646
Showing 1-10 of 22 resultsSorted by cheapest first
Compare providers for flights from Idaho Falls to St. Louis
Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Idaho Falls to St. Louis in March.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy- | Trust Score*1 star |
- Most accurate provider: When it comes to deals on Idaho Falls-St. Louis flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Idaho Falls-St. Louis flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Idaho Falls-St. Louis flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on Idaho Falls-St. Louis flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Idaho Falls-St. Louis flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.
Best time to book a flight from Idaho Falls to St. Louis
Have a flexible travel schedule? Discover the best time to fly to St. Louis from Idaho Falls with our price prediction graph.
IDA-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 Falls to St. Louis
What is the cheapest month to book a flight from Idaho Falls to St. Louis?
Currently, July is the cheapest month in which you can book a flight from Idaho Falls to St. Louis (average of $218). Flying from Idaho Falls to St. Louis in June is currently the most expensive (average of $472). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.
How much does it cost to fly round-trip from Idaho Falls to St. Louis?
Reviews of airlines servicing St. Louis
Get insights into the airlines that provide service to St. Louis. 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 St. Louis. Reviews last updated March 12, 2026.
Read reviews from past customers who have flown United Airlines and American Airlines from Idaho Falls to St. Louis. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Entertainment
7.1
Crew
8.1
Overall
7.4
Comfort
7.3
Food
6.6
Boarding
7.7
Reviews
1 / 20
10.0
ExcellentDane,Jan 2026
TYS - IAD
Entertainment
7.1
Crew
8.1
Overall
7.4
Comfort
7.3
Food
6.6
Boarding
7.7
Reviews
1 / 20
10.0
ExcellentDane,Jan 2026
TYS - IAD
Entertainment
7.1
Crew
8.1
Overall
7.4
Comfort
7.3
Food
6.6
Boarding
7.7
Reviews
1 / 20
10.0
ExcellentDane,Jan 2026
TYS - IAD
Related info for your journey
Find useful and relevant information for your journey from Idaho Falls 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
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Idaho Falls and St. Louis flights
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Top 2 airlines flying from Idaho Falls to St. Louis
Discover the top 2 airlines that operate flights from Idaho Falls 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 12, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$326 | Average$384 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$387 | Average$510 | FlexibilityNo cancel fee | On-time69% |