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 $510. Other airlines that can offer you cheap pricing are Delta, from $559, and United Airlines, from $595. Users have found that Alaska Airlines is 20% cheaper than the other options available to this destination.

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

The cheapest airlines for a one-way flight from Idaho Falls to St. Louis are Delta ($193), United Airlines ($198), and American Airlines ($280).

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

Currently, August is the cheapest month in which you can book a flight from Idaho Falls to St. Louis (average of $311). Flying from Idaho Falls to St. Louis in March is currently the most expensive (average of $356). 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.

What is the cheapest day to fly from Idaho Falls to St. Louis?

Travelers seeking maximum savings on their Idaho Falls to St. Louis flight should consider departing on Friday evenings when fares are most often at their lowest. Thursday mornings flights should be avoided if possible as fares are typically the most expensive at this time.

What is the cheapest day to fly round-trip from Idaho Falls to St. Louis?

Sunday flights are found to be more expensive to fly from Idaho Falls to St. Louis. This shouldn’t discourage you from searching, as you can still find great deals by being flexible with your options. Use our search form to find deals on tickets to St. Louis.

What is the cheapest month to fly from Idaho Falls to St. Louis?

Our data shows that February tends to be the cheapest month to fly to St. Louis from Idaho Falls. Users have commonly found prices around $641 for the month, but tickets can be as low as $323. Due to multiple factors, prepare for potentially higher prices in July.

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.

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.

$193+ Flights from Idaho Falls to St. Louis

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1. Tell us where you want to go

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Cheap flight deals from Idaho Falls to St. Louis

Most accurate provider	FlightHub 3 stars
Most trusted provider	FlightHub 3 stars
Round-trip from	$510 (Alaska Airlines)
One-way from	$193 (Delta)
Popular in	July
Cheapest in	February
Average price	$394

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. 11% potential increase in price ($82 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 5% potential price decrease ($34 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in April 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 April 11, 2025.

Thu 6/51:51 pmIDA - STL

1 stop8h 28mAmerican Airlines

Sat 6/143:08 pmSTL - IDA

1 stop7h 27mAmerican Airlines

Deal found 4/11

$490

Wed 4/236:00 amIDA - STL

1 stop7h 08mAlaska Airlines

Fri 4/253:08 pmSTL - IDA

1 stop8h 28mAlaska Airlines

Deal found 4/10

$510

Wed 4/231:10 pmIDA - STL

1 stop6h 53mDelta

Fri 4/256:50 amSTL - IDA

2 stops12h 25mDelta

Deal found 4/10

$559

Thu 6/55:00 amIDA - STL

1 stop14h 48mUnited Airlines

Sat 6/145:27 pmSTL - IDA

2 stops17h 17mUnited Airlines

Deal found 4/11

$588

Best flights from Idaho Falls to St. Louis
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 April 11, 2025.

Wed 4/236:00 amIDA - STL

1 stop7h 08mAlaska Airlines

Fri 4/253:08 pmSTL - IDA

1 stop8h 28mAlaska Airlines

Deal found 4/10

$510

Wed 4/231:10 pmIDA - STL

1 stop6h 53mDelta

Fri 4/256:50 amSTL - IDA

2 stops12h 25mDelta

Deal found 4/10

$559

Fri 7/45:00 amIDA - STL

1 stop6h 46mUnited Airlines

Sun 7/65:15 amSTL - IDA

1 stop5h 29mUnited Airlines

Deal found 4/10

$595

Last-minute flights from Idaho Falls to St. Louis
Discover last-minute flight deals from Idaho Falls to St. Louis. Data last updated April 11, 2025 and is based on user searches.

Wed 4/236:00 amIDA - STL

1 stop7h 08mAlaska Airlines

Fri 4/253:08 pmSTL - IDA

1 stop8h 28mAlaska Airlines

Deal found 4/10

$510

Wed 4/231:10 pmIDA - STL

1 stop6h 53mDelta

Fri 4/256:50 amSTL - IDA

2 stops12h 25mDelta

Deal found 4/10

$559

One-way flights from Idaho Falls to St. Louis
Search for one-way flight options from Idaho Falls to St. Louis. Find affordable one-way fares based on user searches. Data last updated April 11, 2025.

Mon 6/306:52 pmIDA - STL

1 stop4h 51mDelta

Deal found 4/10

$193

Mon 6/3010:45 amIDA - STL

2 stops11h 00mUnited Airlines

Deal found 4/10

$198

Sat 6/71:51 pmIDA - STL

1 stop8h 28mAmerican Airlines

Deal found 4/10

$280

Cheapflights Fare Finder

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

Price

Idaho FallsSt. Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

Wed 4/23

6:00 am-2:08 pm

1 stop7h 08m

Lambert-St Louis

Fri 4/25

3:08 pm-10:36 pm

1 stop8h 28m

$510

Idaho FallsSt. Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

Wed 4/23

1:10 pm-9:03 pm

1 stop6h 53m

Lambert-St Louis

Fri 4/25

6:50 am-6:15 pm

2 stops12h 25m

$559

Idaho FallsSt. Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

Fri 7/4

5:00 am-12:46 pm

1 stop6h 46m

Lambert-St Louis

Sun 7/6

5:15 am-9:44 am

1 stop5h 29m

$595

Idaho FallsSt. Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

Mon 6/30

6:52 pm-12:43 am

1 stop4h 51m

$193

Idaho FallsSt. Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

Mon 6/30

10:45 am-10:45 pm

2 stops11h 00m

$198

Idaho FallsSt. Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

Sat 6/7

1:51 pm-11:19 pm

1 stop8h 28m

$280

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/10

Compare providers for flights from Idaho Falls to St. Louis

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 April.

Provider	Price Accuracy	Trust Score*
Expedia	Price Accuracy1 star	Trust Score*3 stars
FlightHub	Price Accuracy3 stars	Trust Score*3 stars
eDreams	Price Accuracy3 stars	Trust Score*3 stars
JustAirTicket	Price Accuracy-	Trust 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 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.

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?

Unlike at noon, when flights are generally more expensive, you can save up to 23% on flights from Idaho Falls to St. Louis by exploring options for tickets in the afternoon.

Rainfall in St. Louis by month

In terms of precipitation, rainfall in St. Louis ranges from 2.2 - 4.7 inches per month. May is typically the wettest month, when rainfall can reach 4.7 in. February is typically the driest time to visit St. Louis when rainfall is around 2.2 in.

Temperature in St. Louis by month

If weather is an important factor for your trip to St. Louis, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 80.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 32.0 F).

Reviews of airlines servicing St. Louis

Alaska Airlines

8.0

Very good

9,851 reviews

Reviews

1 / 20

4.0

Okay

Anonymous,Apr 2025

LAS - STS

flight was delayed both ways even tho the weather was clear >

Alaska Airlines

8.0

Very good

9,851 reviews

Alaska Airlines

8.0

Very good

9,851 reviews

Reviews

1 / 20

4.0

Okay

Anonymous,Apr 2025

LAS - STS

flight was delayed both ways even tho the weather was clear >

Delta

8.0

Very good

7,910 reviews

Alaska Airlines

8.0

Very good

9,851 reviews

Reviews

1 / 20

4.0

Okay

Anonymous,Apr 2025

LAS - STS

flight was delayed both ways even tho the weather was clear >

United Airlines

7.4

Good

8,636 reviews

Alaska Airlines

8.0

Very good

9,851 reviews

Reviews

1 / 20

4.0

Okay

Anonymous,Apr 2025

LAS - STS

flight was delayed both ways even tho the weather was clear >

American Airlines

7.2

Good

10,000 reviews

Alaska Airlines

8.0

Very good

9,851 reviews

Reviews

1 / 20

4.0

Okay

Anonymous,Apr 2025

LAS - STS

flight was delayed both ways even tho the weather was clear >

Related info for your journey

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 $510. Other airlines that can offer you cheap pricing are Delta, from $559, and United Airlines, from $595. Users have found that Alaska Airlines is 20% cheaper than the other options available to this destination.
What are the cheapest airlines to fly from Idaho Falls to St. Louis one-way?
The cheapest airlines for a one-way flight from Idaho Falls to St. Louis are Delta ($193), United Airlines ($198), and American Airlines ($280).
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.
What is the cheapest month to book a flight from Idaho Falls to St. Louis?
Currently, August is the cheapest month in which you can book a flight from Idaho Falls to St. Louis (average of $311). Flying from Idaho Falls to St. Louis in March is currently the most expensive (average of $356). 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

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Other flights to St. Louis

Top airline flying from Idaho Falls to St. Louis

Airline	Cheapest	Average	Flexibility	On-time
Delta	Cheapest$406	Average$622	FlexibilityNo cancel fee	On-timeN/A

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$193+ 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 6/30. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from Idaho Falls to St. Louis with Cheapflights

1. Tell us where you want to go

2. Select your favorite providers

3. Compare prices and book

Cheap flight deals from Idaho Falls to St. Louis

Most accurate provider

Most trusted provider

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Find flight deals from Idaho Falls to St. Louis

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 April 11, 2025.

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 April 11, 2025.

Cheapflights Fare Finder

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

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 April.

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.

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 April 11, 2025.

Rainfall in St. Louis by month

Plan your trip to St. Louis by taking into account the average rainfall totals by month.

Temperature in St. Louis by month

Plan your trip to St. Louis by taking into account the average temperature totals by month.

Reviews of airlines servicing St. Louis

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.

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

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

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

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

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

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

Traveling to a place near Idaho Falls?

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.

Alternative routes for Idaho Falls to St. Louis

See prices for flight routes from nearby airports that may be better suited for you.

Top airline flying from Idaho Falls to St. Louis

100% Free

Book with Flexibility

Travel Smart

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 April 11, 2025.