$165+ 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 9/14. Fares are subject to change and may not be available on all flights or dates of travel.
IDA — STL
Aug 23 — Aug 301
Round-trip
1 adult, Economy
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Find cheap flights from Idaho Falls 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
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.3. Compare prices and book
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 Falls to St. Louis
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Best
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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 July 24, 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 July 24, 2026.
This Delta deal was found by Cheapflights users on 7/20. 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.
Wed 9/236:57 pm
IDA
- STL
1 stop4h 47m
Delta
Sat 9/268:00 am
STL
- IDA
1 stop5h 15m
Delta
Deal found 7/20![Delta logo]()
$319
This Delta deal was found by Cheapflights users on 7/21. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/267:00 pm
IDA
- STL
1 stop4h 41m
Delta
Wed 9/95:00 pm
STL
- IDA
1 stop6h 22m
Delta
Deal found 7/21![Delta logo]()
$329
This United Airlines deal was found by Cheapflights users on 7/23. 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.
Fri 10/94:05 pm
IDA
- STL
1 stop6h 39m
United Airlines
Sun 10/115:10 am
STL
- IDA
1 stop5h 43m
United Airlines
Deal found 7/23![United Airlines logo]()
$367
This Alaska Airlines deal was found by Cheapflights users on 7/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/246:09 am
IDA
- STL
1 stop8h 35m
Alaska Airlines
Wed 10/287:02 am
STL
- IDA
1 stop9h 18m
Alaska Airlines
Deal found 7/21![Alaska Airlines logo]()
$369
This Delta deal was found by Cheapflights users on 7/22. 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.
Thu 8/67:00 pm
IDA
- STL
1 stop4h 41m
Delta
Tue 8/118:00 am
STL
- IDA
1 stop7h 35m
Delta
Deal found 7/22![Delta logo]()
$379
This American Airlines deal was found by Cheapflights users on 7/21. 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 8/262:20 pm
IDA
- STL
1 stop8h 22m
American Airlines
Wed 9/97:26 am
STL
- IDA
2 stops14h 54m
American Airlines
Deal found 7/21![American Airlines logo]()
$407
This United Airlines deal was found by Cheapflights users on 7/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/55:54 pm
IDA
- STL
1 stop5h 03m
United Airlines
Mon 8/105:10 am
STL
- IDA
1 stop5h 40m
United Airlines
Deal found 7/20![United Airlines logo]()
$419
This Delta deal was found by Cheapflights users on 7/22. 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.
Thu 8/67:00 pm
IDA
- STL
1 stop4h 41m
Delta
Mon 8/102:32 pm
STL
- IDA
1 stop4h 48m
Delta
Deal found 7/22![Delta logo]()
$440
This Delta deal was found by Cheapflights users on 7/22. 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 9/86:57 pm
IDA
- STL
2 stops13h 37m
Delta
Fri 9/115:00 pm
STL
- IDA
1 stop6h 22m
Delta
Deal found 7/22![Delta logo]()
$456
This American Airlines deal was found by Cheapflights users on 7/22. 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 8/512:06 pm
IDA
- STL
1 stop7h 20m
American Airlines
Mon 8/103:32 pm
STL
- IDA
1 stop6h 48m
American Airlines
Deal found 7/22![American Airlines logo]()
$462
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 July 24, 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 July 24, 2026.
This Delta deal was found by Cheapflights users on 7/20. 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.
Wed 9/236:57 pm
IDA
- STL
1 stop4h 47m
Delta
Sat 9/268:00 am
STL
- IDA
1 stop5h 15m
Delta
Deal found 7/20![Delta logo]()
$319
This United Airlines deal was found by Cheapflights users on 7/21. 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.
Wed 8/55:54 pm
IDA
- STL
1 stop5h 03m
United Airlines
Sun 8/95:10 am
STL
- IDA
1 stop5h 40m
United Airlines
Deal found 7/21![United Airlines logo]()
$369
This Alaska Airlines deal was found by Cheapflights users on 7/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/241:46 pm
IDA
- STL
1 stop9h 13m
Alaska Airlines
Wed 10/284:42 pm
STL
- IDA
1 stop7h 12m
Alaska Airlines
Deal found 7/18![Alaska Airlines logo]()
$369
This Delta deal was found by Cheapflights users on 7/22. 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 9/86:57 pm
IDA
- STL
2 stops13h 37m
Delta
Fri 9/115:00 pm
STL
- IDA
1 stop6h 22m
Delta
Deal found 7/22![Delta logo]()
$456
This United Airlines deal was found by Cheapflights users on 7/20. 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 10/242:28 pm
IDA
- STL
1 stop5h 08m
United Airlines
Wed 10/287:30 am
STL
- IDA
2 stops14h 51m
United Airlines
Deal found 7/20![United Airlines logo]()
$466
This Priceline deal was found by Cheapflights users on 7/22. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/86:18 am
IDA
- STL
1 stop7h 03m
Alaska Airlines
Fri 9/113:19 pm
STL
- IDA
1 stop8h 37m
Alaska Airlines
Deal found 7/22![Alaska Airlines logo]()
$479
Last-minute flights from Idaho Falls to St. LouisDiscover last-minute flight deals from Idaho Falls to St. Louis. Data last updated July 24, 2026 and is based on user searches.
Discover last-minute flight deals from Idaho Falls to St. Louis. Data last updated July 24, 2026 and is based on user searches.
This United Airlines deal was found by Cheapflights users on 7/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/35:54 pm
IDA
- STL
1 stop5h 03m
United Airlines
Fri 8/75:10 am
STL
- IDA
1 stop5h 40m
United Airlines
Deal found 7/19![United Airlines logo]()
$479
This United Airlines deal was found by Cheapflights users on 7/21. 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.
Wed 8/55:54 pm
IDA
- STL
1 stop5h 03m
United Airlines
Sun 8/95:10 am
STL
- IDA
1 stop5h 40m
United Airlines
Deal found 7/21![United Airlines logo]()
$369
This United Airlines deal was found by Cheapflights users on 7/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/55:54 pm
IDA
- STL
1 stop5h 03m
United Airlines
Mon 8/105:10 am
STL
- IDA
1 stop5h 40m
United Airlines
Deal found 7/20![United Airlines logo]()
$419
This American Airlines deal was found by Cheapflights users on 7/22. 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 8/512:06 pm
IDA
- STL
1 stop7h 20m
American Airlines
Mon 8/103:32 pm
STL
- IDA
1 stop6h 48m
American Airlines
Deal found 7/22![American Airlines logo]()
$462
This Delta deal was found by Cheapflights users on 7/22. 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.
Thu 8/67:00 pm
IDA
- STL
1 stop4h 41m
Delta
Tue 8/118:00 am
STL
- IDA
1 stop7h 35m
Delta
Deal found 7/22![Delta logo]()
$379
This Delta deal was found by Cheapflights users on 7/22. 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.
Thu 8/67:00 pm
IDA
- STL
1 stop4h 41m
Delta
Mon 8/102:32 pm
STL
- IDA
1 stop4h 48m
Delta
Deal found 7/22![Delta logo]()
$440
This Delta deal was found by Cheapflights users on 7/21. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/267:00 pm
IDA
- STL
1 stop4h 41m
Delta
Wed 9/95:00 pm
STL
- IDA
1 stop6h 22m
Delta
Deal found 7/21![Delta logo]()
$329
This American Airlines deal was found by Cheapflights users on 7/21. 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 8/262:20 pm
IDA
- STL
1 stop8h 22m
American Airlines
Wed 9/97:26 am
STL
- IDA
2 stops14h 54m
American Airlines
Deal found 7/21![American Airlines logo]()
$407
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 July 24, 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 July 24, 2026.
This Delta deal was found by Cheapflights users on 7/20. 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.
Mon 9/146:57 pm
IDA
- STL
1 stop4h 47m
Delta
Deal found 7/20![Delta logo]()
$165
This Kiwi.com deal was found by Cheapflights users on 7/20. 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.
Mon 9/146:21 pm
IDA
- STL
3 stops38h 19m
Multiple Airlines
Deal found 7/20![Multiple Airlines logo]()
$185
This United Airlines deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/55:54 pm
IDA
- STL
1 stop5h 03m
United Airlines
Deal found 7/22![United Airlines logo]()
$190
This Delta deal was found by Cheapflights users on 7/21. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/1511:35 am
IDA
- STL
2 stops9h 28m
Delta
Deal found 7/21![Delta logo]()
$195
This Delta deal was found by Cheapflights users on 7/19. 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 7/287:00 pm
IDA
- STL
1 stop4h 41m
Delta
Deal found 7/19![Delta logo]()
$230
This United Airlines deal was found by Cheapflights users on 7/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/2910:35 am
IDA
- STL
2 stops12h 09m
United Airlines
Deal found 7/19![United Airlines logo]()
$280
This United Airlines deal was found by Cheapflights users on 7/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/152:25 pm
IDA
- STL
1 stop5h 21m
United Airlines
Deal found 7/21![United Airlines logo]()
$293
This United Airlines deal was found by Cheapflights users on 7/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/314:14 pm
IDA
- STL
1 stop6h 43m
United Airlines
Deal found 7/21![United Airlines logo]()
$315
This United Airlines deal was found by Cheapflights users on 7/19. 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.
Thu 7/3010:35 am
IDA
- STL
2 stops12h 09m
United Airlines
Deal found 7/19![United Airlines logo]()
$356
This Kiwi.com deal was found by Cheapflights users on 7/19. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/3110:47 pm
IDA
- STL
2 stops43h 36m
Multiple Airlines
Deal found 7/19![Multiple Airlines logo]()
$380
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 July 24, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $319 (Delta) |
One-way from | $165 (Delta) |
Popular in | December |
Cheapest in | May |
Average price | $738 |
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 July 24, 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
Wed 9/23
6:57 pm-12:44 am
1 stop4h 47m
Lambert-St Louis
Sat 9/26
8:00 am-12:15 pm
1 stop5h 15m
$319
Idaho FallsSt. Louis
IDA - STL
IDASTL
Idaho Falls Fanning Field
Wed 8/5
5:54 pm-11:57 pm
1 stop5h 03m
Lambert-St Louis
Sun 8/9
5:10 am-9:50 am
1 stop5h 40m
$369
Idaho FallsSt. Louis
IDA - STL
IDASTL
Idaho Falls Fanning Field
Sat 10/24
1:46 pm-11:59 pm
1 stop9h 13m
Lambert-St Louis
Wed 10/28
4:42 pm-10:54 pm
1 stop7h 12m
$369
Idaho FallsSt. Louis
IDA - STL
IDASTL
Idaho Falls Fanning Field
Tue 9/8
6:57 pm-9:34 am
2 stops13h 37m
Lambert-St Louis
Fri 9/11
5:00 pm-10:22 pm
1 stop6h 22m
$456
Idaho FallsSt. Louis
IDA - STL
IDASTL
Idaho Falls Fanning Field
Sat 10/24
2:28 pm-8:36 pm
1 stop5h 08m
Lambert-St Louis
Wed 10/28
7:30 am-9:21 pm
2 stops14h 51m
$466
Idaho FallsSt. Louis
IDA - STL
IDASTL
Idaho Falls Fanning Field
Tue 9/8
6:18 am-2:21 pm
1 stop7h 03m
Lambert-St Louis
Fri 9/11
3:19 pm-10:56 pm
1 stop8h 37m
$479
Cheapest one-way
Idaho FallsSt. Louis
IDA - STL
IDASTL
Idaho Falls Fanning Field
Mon 9/14
6:57 pm-12:44 am
1 stop4h 47m
$165
Idaho FallsSt. Louis
IDA - STL
IDASTL
Idaho Falls Fanning Field
Mon 9/14
6:21 pm-9:40 am
3 stops38h 19m
$185
Idaho FallsSt. Louis
IDA - STL
IDASTL
Idaho Falls Fanning Field
Wed 8/5
5:54 pm-11:57 pm
1 stop5h 03m
$190
Idaho FallsSt. Louis
IDA - STL
IDASTL
Idaho Falls Fanning Field
Sat 8/15
6:00 am-1:38 pm
1 stop6h 38m
$190
Showing 1-10 of 15 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 July.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars |
- 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, May is the cheapest month in which you can book a flight from Idaho Falls to St. Louis (average of $443). Flying from Idaho Falls to St. Louis in December is currently the most expensive (average of $863). 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?
Airfare is below average for this route at the moment.
Idaho Falls to St. Louis flights typically cost between $530 and $696 in September.The cheapest round-trip price found within the last 5 days was $319 on Delta (Sep 23-Sep 26).
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 July 24, 2026.
Read reviews from past customers who have flown Delta and United 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.
Crew
8.5
Boarding
8.1
Comfort
7.8
Entertainment
7.8
Overall
7.8
Food
7.2
Reviews
1 / 20
10.0
ExcellentAnonymous,May 2026
SEA - KOA
Crew
8.5
Boarding
8.1
Comfort
7.8
Entertainment
7.8
Overall
7.8
Food
7.2
Reviews
1 / 20
10.0
ExcellentAnonymous,May 2026
SEA - KOA
Crew
8.5
Boarding
8.1
Comfort
7.8
Entertainment
7.8
Overall
7.8
Food
7.2
Reviews
1 / 20
10.0
ExcellentAnonymous,May 2026
SEA - KOA
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
Eureka
Maryland Heights
Collinsville
Wentzville
Glencoe
Chesterfield
Farmington
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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Idaho Falls and St. Louis flights
Browse other Idaho Falls and St. Louis flight options. Last updated on July 24, 2026.
Other flights from Idaho Falls
Browse through other flights departing from Idaho Falls. Flights are based on user searches made on Cheapflights and were last updated on July 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 July 24, 2026.
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 July 24, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$185 | Average$558 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$387 | Average$510 | FlexibilityNo cancel fee | On-time69% |