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

United Airlines, at $427, was found to be the cheapest airline from St. Louis to Idaho Falls.Alternate airlines to your destination round-trip include Delta and Alaska Airlines. United Airlines is priced at 32% lower than the current average price of a flight leaving 3 months from now.

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

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

What are the most popular airlines that fly from St. Louis to Idaho Falls?

Consider American Airlines, Delta or United Airlines when booking your flight. These represent the most popular airlines when flying from St. Louis to Idaho Falls.

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

Users have found that leaving on a Monday can be a cost-effective option. It’s possible to save up to 30% on your flight compared to booking on days when demand is much higher.

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

Our data shows that January tends to be the cheapest month to fly to Idaho Falls from St. Louis. Users have commonly found prices around $636 for the month, but tickets can be as low as $307. Due to multiple factors, prepare for potentially higher prices in April.

What is the cheapest time of day to fly from STL to IDA?

A simple way to save on the total cost of your ticket is to fly from St. Louis to Idaho Falls at noon. If you’re flexible enough to do this you can expect to save up to 5% on your trip compared to booking a flight in the afternoon.

Most accurate provider : When it comes to deals on St. Louis-Idaho Falls flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on St. Louis-Idaho Falls flight deals on Cheapflights vs. FlightHub >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.

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.

$214+ Flights from St. Louis to Idaho Falls - Compare & Save Big

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1. Tell us where you want to go

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Cheap flight deals from St. Louis to Idaho Falls

Most accurate provider	FlightHub 3 stars
Most trusted provider	eDreams 3 stars
Round-trip from	$427 (United Airlines)
One-way from	$214 (United Airlines)
Popular in	April
Cheapest in	January
Average price	$1,188

Provider with most accurate pricing for Lambert-St Louis-Idaho Falls Fanning Field flight deals.

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Provider most trusted by Cheapflights users for Lambert-St Louis-Idaho Falls Fanning Field flights.

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From Lambert-St Louis to Idaho Falls Fanning Field

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One-way flight from Lambert-St Louis to Idaho Falls Fanning Field

Search Deals

Highest demand for flights based on searches. 23% potential increase in price ($200 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 8% potential price decrease ($50 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in April 2025

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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 abril 29, 2025.

lun. 5/265:20 amSTL - IDA

1 stop5h 24mUnited Airlines

jue. 5/292:25 pmIDA - STL

1 stop5h 23mUnited Airlines

Deal found 4/29

$427

vie. 7/116:40 amSTL - IDA

2 stops12h 31mDelta

lun. 7/146:52 pmIDA - STL

1 stop4h 46mDelta

Deal found 4/28

$446

sáb. 8/29:25 amSTL - IDA

2 stops14h 14mAlaska Airlines

dom. 8/34:03 pmIDA - STL

2 stops16h 15mAlaska Airlines

Deal found 4/29

$760

Best flights from St. Louis to Idaho Falls
Discover carefully curated flight deals from St. Louis to Idaho Falls that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated abril 29, 2025.

lun. 5/265:20 amSTL - IDA

1 stop5h 24mUnited Airlines

jue. 5/292:25 pmIDA - STL

1 stop5h 23mUnited Airlines

Deal found 4/29

$427

vie. 7/116:40 amSTL - IDA

2 stops12h 31mDelta

lun. 7/146:52 pmIDA - STL

1 stop4h 46mDelta

Deal found 4/28

$446

sáb. 8/29:25 amSTL - IDA

2 stops14h 14mAlaska Airlines

dom. 8/34:03 pmIDA - STL

2 stops16h 15mAlaska Airlines

Deal found 4/29

$760

Last-minute flights from St. Louis to Idaho Falls
Discover last-minute flight deals from St. Louis to Idaho Falls. Data last updated abril 29, 2025 and is based on user searches.

vie. 5/22:23 pmSTL - IDA

1 stop4h 52mDelta

vie. 5/96:50 pmIDA - STL

1 stop5h 09mDelta

Deal found 4/28

$716

lun. 5/265:20 amSTL - IDA

1 stop5h 24mUnited Airlines

jue. 5/292:25 pmIDA - STL

1 stop5h 23mUnited Airlines

Deal found 4/29

$427

One-way flights from St. Louis to Idaho Falls
Search for one-way flight options from St. Louis to Idaho Falls. Find affordable one-way fares based on user searches. Data last updated abril 29, 2025.

jue. 6/54:32 pmSTL - IDA

1 stop7h 19mUnited Airlines

Deal found 4/28

$214

mié. 5/2111:32 amSTL - IDA

2 stops7h 38mDelta

Deal found 4/29

$215

Cheapflights Fare Finder

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

Fly from

Fly to

Route

Depart

Return

Price

St. LouisIdaho Falls

STL - IDA

STLIDA

Lambert-St Louis

lun. 5/26

5:20 am-9:44 am

1 stop5h 24m

Idaho Falls Fanning Field

jue. 5/29

2:25 pm-8:48 pm

1 stop5h 23m

$427

St. LouisIdaho Falls

STL - IDA

STLIDA

Lambert-St Louis

vie. 7/11

6:40 am-6:11 pm

2 stops12h 31m

Idaho Falls Fanning Field

lun. 7/14

6:52 pm-12:38 am

1 stop4h 46m

$446

St. LouisIdaho Falls

STL - IDA

STLIDA

Lambert-St Louis

sáb. 8/2

9:25 am-10:39 pm

2 stops14h 14m

Idaho Falls Fanning Field

dom. 8/3

4:03 pm-9:18 am

2 stops16h 15m

$760

St. LouisIdaho Falls

STL - IDA

STLIDA

Lambert-St Louis

jue. 6/5

4:32 pm-10:51 pm

1 stop7h 19m

$214

St. LouisIdaho Falls

STL - IDA

STLIDA

Lambert-St Louis

mié. 5/21

11:32 am-6:10 pm

2 stops7h 38m

$215

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/28

Compare providers for flights from St. Louis to Idaho Falls

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 April.

Provider	Price Accuracy	Trust Score*
Expedia	Price Accuracy1 star	Trust Score*3 stars
FlightHub	Price Accuracy3 stars	Trust Score*2 stars
eDreams	Price Accuracy3 stars	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 St. Louis-Idaho Falls flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on St. Louis-Idaho Falls flight deals on Cheapflights vs. FlightHub >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, October is the cheapest month in which you can book a flight from St. Louis to Idaho Falls (average of $380). Flying from St. Louis to Idaho Falls in July is currently the most expensive (average of $628). 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.

Rainfall in Idaho Falls by month

In terms of precipitation, rainfall in Idaho Falls ranges from 0.6 - 2.0 inches per month. May is typically the wettest month, when rainfall can reach 2.0 in. July is typically the driest time to visit Idaho Falls when rainfall is around 0.6 in.

Temperature in Idaho Falls by month

If weather is an important factor for your trip to Idaho Falls, 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 69.8 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 23.0 F).

Reviews of airlines servicing Idaho Falls

Alaska Airlines

8.0

Very good

9,968 reviews

Reviews

1 / 20

10.0

Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

Alaska Airlines

8.0

Very good

9,968 reviews

Alaska Airlines

8.0

Very good

9,968 reviews

Reviews

1 / 20

10.0

Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

Delta

8.0

Very good

7,936 reviews

Alaska Airlines

8.0

Very good

9,968 reviews

Reviews

1 / 20

10.0

Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

United Airlines

7.4

Good

8,696 reviews

Alaska Airlines

8.0

Very good

9,968 reviews

Reviews

1 / 20

10.0

Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

Related info for your journey

What are the cheapest airlines flying from St. Louis to Idaho Falls round-trip?
United Airlines, at $427, was found to be the cheapest airline from St. Louis to Idaho Falls.Alternate airlines to your destination round-trip include Delta and Alaska Airlines. United Airlines is priced at 32% lower than the current average price of a flight leaving 3 months from now.
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, October is the cheapest month in which you can book a flight from St. Louis to Idaho Falls (average of $380). Flying from St. Louis to Idaho Falls in July is currently the most expensive (average of $628). 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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Top 3 airlines flying from St. Louis to Idaho Falls

Airline	Cheapest	Average	Flexibility	On-time
American Airlines	Cheapest$305	Average$645	FlexibilityNo cancel fee	On-time71%
Delta	Cheapest$314	Average$576	FlexibilityNo cancel fee	On-timeN/A
United Airlines	Cheapest$464	Average$673	FlexibilityNo cancel fee	On-time69%

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$214+ 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 6/5. Fares are subject to change and may not be available on all flights or dates of travel.

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

1. Tell us where you want to go

2. Select your favorite providers

3. Compare prices and book

Cheap flight deals from St. Louis to Idaho Falls

Most accurate provider

Most trusted provider

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Find flight deals from St. Louis to Idaho Falls

Cheapest flights from St. Louis to Idaho FallsExplore 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 abril 29, 2025.

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 abril 29, 2025.

Cheapflights Fare Finder

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

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 April.

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.

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?

Rainfall in Idaho Falls by month

Plan your trip to Idaho Falls by taking into account the average rainfall totals by month.

Temperature in Idaho Falls by month

Plan your trip to Idaho Falls by taking into account the average temperature totals by month.

Reviews of airlines servicing Idaho Falls

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.

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

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

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

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

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

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Alternative routes for St. Louis to Idaho Falls

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Top 3 airlines flying from St. Louis to Idaho Falls

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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 abril 29, 2025.