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Idaho Falls

$179+ Cheap flights from St. Louis to Idaho Falls (STL - IDA)

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 11/17. Fares are subject to change and may not be available on all flights or dates of travel.
STL — IDA
Nov 27 — Dec 41
Thu 11/27
Thu 12/4
1 adult, Economy
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Find flight deals from St. Louis to Idaho Falls

Cheapest flights from St. Louis to Idaho Falls
Explore the most affordable flight options available from St. Louis to Idaho Falls. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 28, 2025.

This Trip.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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/67:00 amSTL - IDA
1 stop10h 27mHawaiian Airlines
Sat 12/136:05 amIDA - STL
1 stop7h 22mHawaiian Airlines
Deal found 10/27$326
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/611:19 amSTL - IDA
2 stops12h 18mDelta
Sat 12/136:00 amIDA - STL
1 stop6h 30mDelta
Deal found 10/27$344
This United 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/114:55 pmSTL - IDA
1 stop5h 08mUnited Airlines
Sat 11/152:45 pmIDA - STL
1 stop6h 09mUnited Airlines
Deal found 10/27$456
This Delta deal was found by Cheapflights users on 10/28. 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 11/126:34 amSTL - IDA
1 stop7h 00mDelta
Sun 11/166:57 pmIDA - STL
1 stop4h 49mDelta
Deal found 10/28$476
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/1111:39 amSTL - IDA
2 stops11h 40mDelta
Sat 11/156:57 pmIDA - STL
2 stops12h 31mDelta
Deal found 10/27$486
This United Airlines deal was found by Cheapflights users on 10/28. 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 11/124:55 pmSTL - IDA
1 stop6h 57mUnited Airlines
Sun 11/162:45 pmIDA - STL
1 stop6h 09mUnited Airlines
Deal found 10/28$676
This Delta deal was found by Cheapflights users on 10/28. 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 11/15:30 pmSTL - IDA
1 stop5h 45mDelta
Tue 11/46:53 pmIDA - STL
1 stop4h 31mDelta
Deal found 10/28$706

Cheap flight deals from St. Louis to Idaho Falls

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Idaho Falls (IDA). 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 October 28, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$326
(Trip.com)

One-way from

$179
(American Airlines)

Popular in

November

Cheapest in

January

Average price

$541
Provider with most accurate pricing for Lambert-St Louis-Idaho Falls Fanning Field flight deals.
Search Deals
Provider most trusted by Cheapflights users for Lambert-St Louis-Idaho Falls Fanning Field flights.
Search Deals
From Lambert-St Louis to Idaho Falls Fanning Field
Search Deals
One-way flight from Lambert-St Louis to Idaho Falls Fanning Field
Search Deals
Highest demand for flights based on searches. 10% potential increase in price ($56 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($18 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in October 2025
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from St. Louis to Idaho Falls 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 October 28, 2025.
Use the filters below to find and compare flights from St. Louis to Idaho Falls that are best for you.

Fly from

St. Louis

Fly to

Idaho Falls

Route

Depart

Return

Price

St. LouisIdaho Falls

STL - IDA

STLIDA

Lambert-St Louis

Sat 12/6

7:00 am-4:27 pm

1 stop10h 27m

Idaho Falls Fanning Field

Sat 12/13

6:05 am-2:27 pm

1 stop7h 22m

$326

St. LouisIdaho Falls

STL - IDA

STLIDA

Lambert-St Louis

Sat 12/6

11:19 am-10:37 pm

2 stops12h 18m

Idaho Falls Fanning Field

Sat 12/13

6:00 am-1:30 pm

1 stop6h 30m

$344

St. LouisIdaho Falls

STL - IDA

STLIDA

Lambert-St Louis

Tue 3/3

2:55 pm-10:38 pm

1 stop8h 43m

Idaho Falls Fanning Field

Wed 3/4

4:00 pm-11:56 pm

1 stop6h 56m

$348

St. LouisIdaho Falls

STL - IDA

STLIDA

Lambert-St Louis

Thu 2/5

2:38 pm-10:36 pm

1 stop8h 58m

Idaho Falls Fanning Field

Tue 2/10

2:07 pm-10:59 pm

1 stop7h 52m

$395

St. LouisIdaho Falls

STL - IDA

STLIDA

Lambert-St Louis

Tue 3/3

5:00 pm-10:21 pm

1 stop6h 21m

Idaho Falls Fanning Field

Wed 3/4

6:45 pm-9:04 am

2 stops13h 19m

$404

St. LouisIdaho Falls

STL - IDA

STLIDA

Lambert-St Louis

Fri 1/16

2:50 pm-10:59 pm

1 stop9h 09m

Idaho Falls Fanning Field

Mon 1/19

6:58 pm-1:54 pm

1 stop17h 56m

$415

St. LouisIdaho Falls

STL - IDA

STLIDA

Lambert-St Louis

Tue 3/3

6:30 am-1:30 pm

2 stops8h 00m

Idaho Falls Fanning Field

Wed 3/4

10:45 am-10:00 pm

2 stops10h 15m

$429

St. LouisIdaho Falls

STL - IDA

STLIDA

Lambert-St Louis

Mon 11/17

7:00 am-1:28 pm

1 stop7h 28m

$179

St. LouisIdaho Falls

STL - IDA

STLIDA

Lambert-St Louis

Mon 11/17

2:36 pm-10:19 pm

2 stops8h 43m

$208

St. LouisIdaho Falls

STL - IDA

STLIDA

Lambert-St Louis

Mon 11/10

2:36 pm-10:19 pm

2 stops8h 43m

$221

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/26

Showing 1-10 of 17 results
1
2

Compare providers for flights from St. Louis to Idaho Falls

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 St. Louis to Idaho Falls in October.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star
eDreamsPrice Accuracy3 starsTrust Score*3 stars

*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 St. Louis-Idaho Falls flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on St. Louis-Idaho Falls flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from St. Louis-Idaho Falls flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on St. Louis-Idaho Falls 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 St. Louis-Idaho Falls 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 St. Louis to Idaho Falls

Have a flexible travel schedule? Discover the best time to fly to Idaho Falls from St. Louis 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 St. Louis to Idaho Falls

What is the cheapest month to book a flight from St. Louis to Idaho Falls?

Currently, May is the cheapest month in which you can book a flight from St. Louis to Idaho Falls (average of $199). Flying from St. Louis to Idaho Falls in October is currently the most expensive (average of $385). 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 St. Louis to Idaho Falls?

Reviews of airlines servicing Idaho Falls

Get insights into the airlines that provide service to Idaho Falls. 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 Idaho Falls. Reviews last updated October 28, 2025.
Peruse reviews from past customers who have flown with Delta and United Airlines from St. Louis to Idaho Falls to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
7.9
Good
7,994 reviews

Boarding

8.2

Entertainment

7.9

Crew

8.5

Comfort

7.9

Overall

7.9

Food

7.3

Reviews

1 / 20
8.0
Excellent

Matthew,Oct 2025

GSP - ATL

This is always a full flight since it is the connecting route to primary destinations through Atlanta. That said, the crew handles the full load well. Not much more to say, it is a short flight with no in-flight services due to the length.
Delta
7.9
Good
7,994 reviews
Delta
7.9
Good
7,994 reviews

Boarding

8.2

Entertainment

7.9

Crew

8.5

Comfort

7.9

Overall

7.9

Food

7.3

Reviews

1 / 20
8.0
Excellent

Matthew,Oct 2025

GSP - ATL

This is always a full flight since it is the connecting route to primary destinations through Atlanta. That said, the crew handles the full load well. Not much more to say, it is a short flight with no in-flight services due to the length.
United Airlines
7.4
Good
9,001 reviews
Delta
7.9
Good
7,994 reviews

Boarding

8.2

Entertainment

7.9

Crew

8.5

Comfort

7.9

Overall

7.9

Food

7.3

Reviews

1 / 20
8.0
Excellent

Matthew,Oct 2025

GSP - ATL

This is always a full flight since it is the connecting route to primary destinations through Atlanta. That said, the crew handles the full load well. Not much more to say, it is a short flight with no in-flight services due to the length.

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Idaho Falls. 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 St. Louis to Idaho Falls?

    Airlines like Hawaiian Airlines and Delta fly from St. Louis to Idaho Falls in about 10h 27m. The time it takes to get you to your destination can typically vary by up to 1h 51m. Airlines will cover a distance of 1171 mi. Both multi-stop and nonstop flights can be found to your destination and back.

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

    Delta, at $192, was found to be the cheapest airline from St. Louis to Idaho Falls. An alternate airline flying to your destination would be United Airlines. Delta is priced at 61% lower than the current average price of a flight leaving 3 months from now.

  • What are the cheapest airlines to fly from St. Louis to Idaho Falls one-way?

    To fly one-way, consider booking your trip with American Airlines, which is currently one of the cheapest options available, starting at $179. Delta flights start at $208 while deals on Alaska Airlines start at $240 one-way.

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

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

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

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

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

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

  • What is the cheapest month to book a flight from St. Louis to Idaho Falls?

    Currently, May is the cheapest month in which you can book a flight from St. Louis to Idaho Falls (average of $199). Flying from St. Louis to Idaho Falls in October is currently the most expensive (average of $385). 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.

See more FAQs

Traveling to a place near Idaho Falls?

Book flights to Idaho Falls if you plan to visit one of these locations
Rexburg

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Top 2 airlines flying from St. Louis to Idaho Falls

Discover the top 2 airlines that operate flights from St. Louis to Idaho Falls. 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 October 28, 2025.
AirlineCheapestAverageFlexibilityOn-time
DeltaCheapest$192Average$384FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$400Average$585FlexibilityNo cancel feeOn-time69%

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