$175+ Cheap flights from Idaho Falls to St. Louis (IDA - STL)
This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 10/8. Fares are subject to change and may not be available on all flights or dates of travel.
IDA — STL
Oct 11 — Oct 181
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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One-way
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 September 11, 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 September 11, 2026.
This American Airlines deal was found by Cheapflights users on 9/7. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/76:36 am -
2 stops10h 41m
Thu 11/125:00 am -
1 stop9h 05m
Deal found 9/7![American Airlines logo]()
$334
This Delta deal was found by Cheapflights users on 9/7. 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.
Tue 10/136:56 pm -
1 stop4h 48m
Thu 10/152:22 pm -
1 stop4h 54m
Deal found 9/7![Delta logo]()
$349
This Delta deal was found by Cheapflights users on 9/7. 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.
Sat 11/76:00 am -
2 stops9h 38m
Thu 11/129:45 am -
2 stops9h 32m
Deal found 9/7![Delta logo]()
$359
This Alaska Airlines deal was found by Cheapflights users on 9/10. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/316:09 am -
1 stop8h 35m
Wed 11/47:00 am -
1 stop9h 18m
Deal found 9/10![Alaska Airlines logo]()
$399
This United Airlines deal was found by Cheapflights users on 9/10. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/312:35 pm -
1 stop5h 24m
Wed 11/49:40 am -
2 stops12h 29m
Deal found 9/10![United Airlines logo]()
$424
This American Airlines deal was found by Cheapflights users on 9/8. 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.
Mon 10/191:50 pm -
1 stop6h 07m
Fri 10/237:29 am -
1 stop6h 51m
Deal found 9/8![American Airlines logo]()
$427
This Delta deal was found by Cheapflights users on 9/10. 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.
Thu 10/86:56 pm -
1 stop4h 48m
Wed 10/147:45 am -
1 stop5h 37m
Deal found 9/10![Delta logo]()
$454
This United Airlines deal was found by Cheapflights users on 9/10. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/164:05 pm -
1 stop6h 39m
Mon 10/194:39 pm -
1 stop5h 15m
Deal found 9/10![United Airlines logo]()
$456
This United Airlines deal was found by Cheapflights users on 9/10. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/254:05 pm -
1 stop6h 39m
Tue 9/295:10 am -
1 stop5h 43m
Deal found 9/10![United Airlines logo]()
$479
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 September 11, 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 September 11, 2026.
This United Airlines deal was found by Cheapflights users on 9/7. 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.
Sat 11/72:35 pm -
1 stop5h 25m
Thu 11/128:50 am -
1 stop7h 48m
Deal found 9/7![United Airlines logo]()
$349
This Alaska Airlines deal was found by Cheapflights users on 9/10. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/316:09 am -
1 stop8h 35m
Wed 11/47:00 am -
1 stop9h 18m
Deal found 9/10![Alaska Airlines logo]()
$399
This Delta deal was found by Cheapflights users on 9/10. 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.
Thu 10/86:56 pm -
1 stop4h 48m
Wed 10/147:45 am -
1 stop5h 37m
Deal found 9/10![Delta logo]()
$454
This United Airlines deal was found by Cheapflights users on 9/10. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/312:35 pm -
1 stop5h 24m
Wed 11/49:40 am -
2 stops12h 29m
Deal found 9/10![United Airlines logo]()
$424
This United Airlines deal was found by Cheapflights users on 9/10. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/164:05 pm -
1 stop6h 39m
Mon 10/194:39 pm -
1 stop5h 15m
Deal found 9/10![United Airlines logo]()
$456
Last-minute flights from Idaho Falls to St. LouisDiscover last-minute flight deals from Idaho Falls to St. Louis. Data last updated September 11, 2026 and is based on user searches.
Discover last-minute flight deals from Idaho Falls to St. Louis. Data last updated September 11, 2026 and is based on user searches.
This American Airlines deal was found by Cheapflights users on 9/9. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/242:08 pm -
1 stop8h 35m
Sun 9/275:43 am -
1 stop8h 54m
Deal found 9/9![American Airlines logo]()
$483
This United Airlines deal was found by Cheapflights users on 9/10. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/254:05 pm -
1 stop6h 39m
Tue 9/295:10 am -
1 stop5h 43m
Deal found 9/10![United Airlines logo]()
$479
This Delta deal was found by Cheapflights users on 9/10. 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.
Thu 10/86:56 pm -
1 stop4h 48m
Wed 10/147:45 am -
1 stop5h 37m
Deal found 9/10![Delta logo]()
$454
This Delta deal was found by Cheapflights users on 9/7. 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.
Tue 10/136:56 pm -
1 stop4h 48m
Thu 10/152:22 pm -
1 stop4h 54m
Deal found 9/7![Delta logo]()
$349
This American Airlines deal was found by Cheapflights users on 9/7. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/151:50 pm -
1 stop6h 07m
Mon 10/193:20 pm -
1 stop7h 22m
Deal found 9/7![American Airlines logo]()
$493
This United Airlines deal was found by Cheapflights users on 9/10. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/164:05 pm -
1 stop6h 39m
Mon 10/194:39 pm -
1 stop5h 15m
Deal found 9/10![United Airlines logo]()
$456
This American Airlines deal was found by Cheapflights users on 9/8. 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.
Mon 10/191:50 pm -
1 stop6h 07m
Fri 10/237:29 am -
1 stop6h 51m
Deal found 9/8![American Airlines logo]()
$427
This Alaska Airlines deal was found by Cheapflights users on 9/10. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/316:09 am -
1 stop8h 35m
Wed 11/47:00 am -
1 stop9h 18m
Deal found 9/10![Alaska Airlines logo]()
$399
This United Airlines deal was found by Cheapflights users on 9/10. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/312:35 pm -
1 stop5h 24m
Wed 11/49:40 am -
2 stops12h 29m
Deal found 9/10![United Airlines logo]()
$424
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 September 11, 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 September 11, 2026.
This Delta deal was found by Cheapflights users on 9/10. 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.
Thu 10/86:56 pm -
1 stop4h 48m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/10![Delta logo]()
$175
This Priceline deal was found by Cheapflights users on 9/11. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/266:02 am -
1 stop7h 20m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/11![Alaska Airlines logo]()
$210
This Delta deal was found by Cheapflights users on 9/11. 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.
Thu 11/261:11 pm -
2 stops8h 42m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/11![Delta logo]()
$213
This American Airlines deal was found by Cheapflights users on 9/7. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/172:08 pm -
1 stop8h 35m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/7![American Airlines logo]()
$235
This United Airlines deal was found by Cheapflights users on 9/10. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/175:53 pm -
1 stop4h 38m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/10![United Airlines logo]()
$245
This Delta deal was found by Cheapflights users on 9/6. Clicking the “Pick Dates” 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 9/176:57 pm -
1 stop4h 47m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/6![Delta logo]()
$255
This Kiwi.com deal was found by Cheapflights users on 9/8. 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.
Thu 9/178:20 pm -
2 stops45h 57m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/8![Multiple Airlines logo]()
$422
This Alaska Airlines deal was found by Cheapflights users on 9/10. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/83:57 pm -
2 stops30h 49m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/10![Alaska Airlines logo]()
$533
This Kiwi.com deal was found by Cheapflights users on 9/11. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/265:09 pm -
3 stops46h 11m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/11![Multiple Airlines logo]()
$559
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 September 11, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $334 (American Airlines) |
One-way from | $175 (Delta) |
Popular in | December |
Cheapest in | May |
Average price | $480 |
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 7,457,451 searches. Data last updated September 11, 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
Idaho FallsSt. Louis
IDA Idaho Falls Fanning Field - STL Lambert-St Louis
IDASTL
Idaho Falls Fanning Field
Thu 11/26
6:02 am-2:22 pm
1 stop7h 20m
Lambert-St Louis
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$210
Idaho FallsSt. Louis
IDA Idaho Falls Fanning Field - STL Lambert-St Louis
IDASTL
Idaho Falls Fanning Field
Thu 11/26
1:11 pm-10:53 pm
2 stops8h 42m
Lambert-St Louis
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$213
Idaho FallsSt. Louis
IDA Idaho Falls Fanning Field - STL Lambert-St Louis
IDASTL
Idaho Falls Fanning Field
Thu 9/17
2:08 pm-11:43 pm
1 stop8h 35m
Lambert-St Louis
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$235
Quickest round-trip
Idaho FallsSt. Louis
IDA Idaho Falls Fanning Field - STL Lambert-St Louis
IDASTL
Idaho Falls Fanning Field
Thu 9/17
5:53 pm-11:31 pm
1 stop4h 38m
Lambert-St Louis
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$245
Idaho FallsSt. Louis
IDA Idaho Falls Fanning Field - STL Lambert-St Louis
IDASTL
Idaho Falls Fanning Field
Thu 9/17
6:57 pm-12:44 am
1 stop4h 47m
Lambert-St Louis
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$245
Idaho FallsSt. Louis
IDA Idaho Falls Fanning Field - STL Lambert-St Louis
IDASTL
Idaho Falls Fanning Field
Sat 11/7
2:35 pm-9:00 pm
1 stop5h 25m
Lambert-St Louis
Thu 11/12
8:50 am-3:38 pm
1 stop7h 48m
$349
Idaho FallsSt. Louis
IDA Idaho Falls Fanning Field - STL Lambert-St Louis
IDASTL
Idaho Falls Fanning Field
Sat 10/31
6:09 am-3:44 pm
1 stop8h 35m
Lambert-St Louis
Wed 11/4
7:00 am-3:18 pm
1 stop9h 18m
$399
Idaho FallsSt. Louis
IDA Idaho Falls Fanning Field - STL Lambert-St Louis
IDASTL
Idaho Falls Fanning Field
Thu 9/17
8:20 pm-7:17 pm
2 stops45h 57m
Lambert-St Louis
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$422
Idaho FallsSt. Louis
IDA Idaho Falls Fanning Field - STL Lambert-St Louis
IDASTL
Idaho Falls Fanning Field
Sat 10/31
2:35 pm-8:59 pm
1 stop5h 24m
Lambert-St Louis
Wed 11/4
9:40 am-9:09 pm
2 stops12h 29m
$424
Idaho FallsSt. Louis
IDA Idaho Falls Fanning Field - STL Lambert-St Louis
IDASTL
Idaho Falls Fanning Field
Thu 10/8
6:56 pm-12:44 am
1 stop4h 48m
Lambert-St Louis
Wed 10/14
7:45 am-12:22 pm
1 stop5h 37m
$454
Showing 1-10 of 11 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 September.
| 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 $387 and $553 in November.The cheapest round-trip price found within the last 5 days was $334 on American Airlines (Nov 7-Nov 12).
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 September 11, 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.
Entertainment
7.8
Boarding
8.1
Overall
7.8
Crew
8.5
Comfort
7.8
Food
7.2
Reviews
1 / 20
4.0
OkayJennifer,Sep 2026
ORD - LGA
Entertainment
7.8
Boarding
8.1
Overall
7.8
Crew
8.5
Comfort
7.8
Food
7.2
Reviews
1 / 20
4.0
OkayJennifer,Sep 2026
ORD - LGA
Entertainment
7.8
Boarding
8.1
Overall
7.8
Crew
8.5
Comfort
7.8
Food
7.2
Reviews
1 / 20
4.0
OkayJennifer,Sep 2026
ORD - LGA
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 locationsFairview Heights
O'Fallon
Fenton
Swansea
Eureka
Maryland Heights
Collinsville
Wentzville
Edwardsville
Glencoe
Chesterfield
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Idaho Falls and St. Louis flights
Browse other Idaho Falls and St. Louis flight options. Last updated on September 11, 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 September 11, 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 September 11, 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 7,457,451 searches. Data last updated September 11, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$164 | Average$448 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$387 | Average$520 | FlexibilityNo cancel fee | On-time69% |