HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
St. Louis

$148+ 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 11/19. Fares are subject to change and may not be available on all flights or dates of travel.
IDA — STL
nov. 26 — dic. 31
mié. 11/26
mié. 12/3
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

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

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 octubre 27, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$297
(Kiwi.com)

One-way from

$148
(Kiwi.com)

Popular in

January

Cheapest in

February

Average price

$510
Provider with most accurate pricing for Idaho Falls Fanning Field-Lambert-St Louis flight deals.
Search Deals
Provider most trusted by Cheapflights users for Idaho Falls Fanning Field-Lambert-St Louis flights.
Search Deals
From Idaho Falls Fanning Field to Lambert-St Louis
Search Deals
One-way flight from Idaho Falls Fanning Field to Lambert-St Louis
Search Deals
Highest demand for flights based on searches. 9% potential increase in price ($58 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 6% potential price decrease ($32 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in October 2025
Search Deals

Find flight deals from Idaho Falls to St. Louis

Cheapest flights from Idaho Falls to St. Louis
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 octubre 27, 2025.

This Kiwi.com deal was found by Cheapflights users on 10/25. 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.
jue. 11/271:52 pmIDA - STL
1 stop24h 16mMultiple Airlines
sáb. 12/67:43 pmSTL - IDA
2 stops43h 53mMultiple Airlines
Deal found 10/25$297
This American Airlines deal was found by Cheapflights users on 10/27. 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.
mié. 12/37:00 amIDA - STL
1 stop7h 27mAmerican Airlines
mié. 12/102:37 pmSTL - IDA
1 stop8h 59mAmerican Airlines
Deal found 10/27$338
This Delta deal was found by Cheapflights users on 10/25. 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.
jue. 11/276:00 amIDA - STL
1 stop8h 05mDelta
sáb. 12/65:00 pmSTL - IDA
1 stop6h 37mDelta
Deal found 10/25$349
This Alaska Airlines deal was found by Cheapflights users on 10/26. 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.
mié. 12/35:07 pmIDA - STL
1 stop20h 20mAlaska Airlines
mié. 12/107:00 amSTL - IDA
1 stop10h 27mAlaska Airlines
Deal found 10/26$359
This Delta deal was found by Cheapflights users on 10/25. 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.
mié. 12/37:06 pmIDA - STL
1 stop4h 55mDelta
mié. 12/106:15 amSTL - IDA
1 stop7h 22mDelta
Deal found 10/25$372
This Kiwi.com deal was found by Cheapflights users on 10/27. 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.
lun. 11/245:22 pmIDA - STL
2 stops39h 40mMultiple Airlines
lun. 12/13:53 pmSTL - IDA
1 stop22h 39mMultiple Airlines
Deal found 10/27$469
This Kiwi.com deal was found by Cheapflights users on 10/27. 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.
lun. 11/245:22 pmIDA - STL
2 stops39h 40mMultiple Airlines
dom. 11/309:54 pmSTL - IDA
1 stop22h 14mMultiple Airlines
Deal found 10/27$590
This Kiwi.com deal was found by Cheapflights users on 10/27. 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.
mar. 11/256:47 pmIDA - STL
2 stops25h 22mMultiple Airlines
lun. 12/13:53 pmSTL - IDA
1 stop22h 39mMultiple Airlines
Deal found 10/27$718

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 octubre 27, 2025.
Use the filters below to find and compare flights from Idaho Falls to St. Louis that are best for you.

Fly from

Idaho Falls

Fly to

St. Louis

Route

Depart

Return

Price

Idaho FallsSt. Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

mié. 12/3

7:00 am-3:27 pm

1 stop7h 27m

Lambert-St Louis

mié. 12/10

2:37 pm-10:36 pm

1 stop8h 59m

$338

Idaho FallsSt. Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

jue. 11/27

6:00 am-3:05 pm

1 stop8h 05m

Lambert-St Louis

sáb. 12/6

5:00 pm-10:37 pm

1 stop6h 37m

$349

Idaho FallsSt. Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

mié. 12/3

5:07 pm-2:27 pm

1 stop20h 20m

Lambert-St Louis

mié. 12/10

7:00 am-4:27 pm

1 stop10h 27m

$359

Idaho FallsSt. Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

mié. 12/3

7:06 pm-1:01 am

1 stop4h 55m

Lambert-St Louis

mié. 12/10

6:15 am-12:37 pm

1 stop7h 22m

$372

Idaho FallsSt. Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

lun. 11/24

5:22 pm-10:02 am

2 stops39h 40m

Lambert-St Louis

lun. 12/1

3:53 pm-1:32 pm

1 stop22h 39m

$469

Idaho FallsSt. Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

mié. 11/19

1:22 pm-2:29 pm

2 stops24h 07m

$148

Idaho FallsSt. Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

mié. 11/19

6:00 am-1:31 pm

1 stop6h 31m

$170

Idaho FallsSt. Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

jue. 11/13

10:50 am-4:28 pm

1 stop4h 38m

$216

Idaho FallsSt. Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

jue. 11/13

6:57 pm-12:46 am

1 stop4h 49m

$216

Idaho FallsSt. Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

mié. 11/5

2:45 pm-9:54 pm

1 stop6h 09m

$271

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/25

Showing 1-10 of 13 results
1
2

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 October.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star
eDreamsPrice Accuracy3 starsTrust Score*3 stars
JustAirTicketPrice Accuracy-Trust Score*1 star

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Idaho Falls-St. Louis flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Idaho Falls-St. Louis flight deals on Cheapflights vs. eDreams >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 eDreams the most. eDreams 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.
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 time of day to fly from IDA to STL?

Find hourly flight availability from Idaho Falls to St. Louis. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated octubre 27, 2025.

Unlike in the afternoon, when flights are generally more expensive, you can save up to 43% on flights from Idaho Falls to St. Louis by exploring options for tickets at noon.

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 octubre 27, 2025.
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.
United Airlines
7.4
Good
8,997 reviews

Food

6.6

Comfort

7.3

Entertainment

7.1

Overall

7.4

Boarding

7.7

Crew

8.1

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
United Airlines
7.4
Good
8,997 reviews
United Airlines
7.4
Good
8,997 reviews

Food

6.6

Comfort

7.3

Entertainment

7.1

Overall

7.4

Boarding

7.7

Crew

8.1

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
American Airlines
7.2
Good
11,033 reviews
United Airlines
7.4
Good
8,997 reviews

Food

6.6

Comfort

7.3

Entertainment

7.1

Overall

7.4

Boarding

7.7

Crew

8.1

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000

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.

  • How long is the flight from Idaho Falls to St. Louis?

    A quick flight from Idaho Falls to St. Louis can take about 7h 27m. American Airlines provides one of the quickest options available for as low as $338. The distance from Idaho Falls to St. Louis is about 1171 mi. This flight may include one or multiple stops.

  • What are the cheapest airlines flying from Idaho Falls to St. Louis round-trip?

    Cheapflights users have booked flights from Idaho Falls to St. Louis round-trip from $324. Another airline that can offer you cheap pricing is United Airlines. Users have found that American Airlines is 39% cheaper than the other options available to this destination.

  • Can I find deals for flights from Idaho Falls to St. Louis that include hotel bookings?

    Yes. In addition to deals on Idaho Falls to St. Louis flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Idaho Falls to St. Louis?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Idaho Falls to St. Louis.

  • Can I find deals for business class flights from Idaho Falls to St. Louis?

    Yes. Cheapflights offers flight deals from Idaho Falls to St. Louis by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

See more FAQs

Traveling to a place near St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
Edwardsville
O'Fallon
Fairview Heights
Maryland Heights
Collinsville
Eureka
Glencoe
St. Peters
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.

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 octubre 27, 2025.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$324Average$384FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$387Average$510FlexibilityNo cancel feeOn-time69%

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.