What is the cheapest airline that flies from Idaho Falls Fanning Field to Lambert-St Louis?

Delta, Alaska Airlines, and United Airlines are the most popular carriers operating from Idaho Falls Fanning Field to Lambert-St Louis

What airlines fly to St. Louis?

United Airlines, Delta and American Airlines are the top three most popular airlines that fly to St. Louis from Idaho Falls according to our data. United Airlines is the first choice among our users, with 72% of people opting to fly with this airline when traveling to St. Louis. Keep in mind that there are 3 different airlines that fly to St. Louis on a routine basis, so you have a few additional options to choose from.

When did momondo last update prices for flights from Idaho Falls Fanning Field Airport to Lambert-St Louis Airport?

Prices for flights from Idaho Falls Fanning Field Airport to Lambert-St Louis Airport are updated daily.

How many operators does momondo search for flights from Idaho Falls Fanning Field Airport to Lambert-St Louis Airport?

The number of operators available for flights from Idaho Falls Fanning Field Airport to Lambert-St Louis Airport is 3 as of September 2026.

How old do you have to be to fly from Idaho Falls Fanning Field Airport to Lambert-St Louis Airport?

The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Idaho Falls Fanning Field Airport to Lambert-St Louis Airport.

What documentation or ID do you need to fly to Lambert-St Louis Airport?

The necessary travel and health documents for your Lambert-St Louis Airport trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.

$175 Cheap Flights from Idaho Falls to St. Louis in 2026

Discover deals from 900+ travel sites with momondo.

Find the cheapest flights from Idaho Falls to St. Louis

Round-trip

One-way

Last minute

Cheap round-trip flights

Enter your travel dates to find the best prices.

6:09 am - 3:44 pmIDA Idaho Falls Fanning Field-STL Lambert-St Louis

8h 35m1 stop Seattle/Tacoma Intl

7:00 am - 3:18 pmSTL Lambert-St Louis-IDA Idaho Falls Fanning Field

9h 18m1 stop Seattle/Tacoma Intl

$399Alaska Airlines

Sat, Oct 31 - Wed, Nov 4

6:09 am - 3:44 pmIDA Idaho Falls Fanning Field-STL Lambert-St Louis

8h 35m1 stop Seattle/Tacoma Intl

6:00 am - 3:18 pmSTL Lambert-St Louis-IDA Idaho Falls Fanning Field

10h 18m1 stop Seattle/Tacoma Intl

$419Alaska Airlines

Sat, Oct 31 - Wed, Nov 4

6:09 am - 3:44 pmIDA Idaho Falls Fanning Field-STL Lambert-St Louis

8h 35m1 stop Seattle/Tacoma Intl

7:00 am - 3:18 pmSTL Lambert-St Louis-IDA Idaho Falls Fanning Field

9h 18m1 stop Seattle/Tacoma Intl

$419Alaska Airlines

Sat, Oct 31 - Wed, Nov 4

2:35 pm - 8:59 pmIDA Idaho Falls Fanning Field-STL Lambert-St Louis

5h 24m1 stop Denver Intl

9:40 am - 9:09 pmSTL Lambert-St Louis-IDA Idaho Falls Fanning Field

12h 29m2 stops Chicago O'Hare Intl Denver Intl

$424United Airlines

Sat, Oct 31 - Wed, Nov 4

2:35 pm - 8:59 pmIDA Idaho Falls Fanning Field-STL Lambert-St Louis

5h 24m1 stop Denver Intl

9:40 am - 9:09 pmSTL Lambert-St Louis-IDA Idaho Falls Fanning Field

12h 29m2 stops Chicago O'Hare Intl Denver Intl

$444United Airlines

Sat, Oct 31 - Wed, Nov 4

1:58 pm - 8:44 pmIDA Idaho Falls Fanning Field-STL Lambert-St Louis

5h 46m1 stop Chicago O'Hare Intl

5:43 am - 11:45 amSTL Lambert-St Louis-IDA Idaho Falls Fanning Field

7h 02m1 stop Dallas/Fort Worth

$444American Airlines

Thu, Sep 24 - Sun, Sep 27

2:35 pm - 8:59 pmIDA Idaho Falls Fanning Field-STL Lambert-St Louis

5h 24m1 stop Denver Intl

7:30 am - 3:38 pmSTL Lambert-St Louis-IDA Idaho Falls Fanning Field

9h 08m2 stops Chicago O'Hare Intl Denver Intl

$444United Airlines

Sat, Oct 31 - Wed, Nov 4

6:56 pm - 12:44 amIDA Idaho Falls Fanning Field-STL Lambert-St Louis

4h 48m1 stop Salt Lake City

7:45 am - 12:22 pmSTL Lambert-St Louis-IDA Idaho Falls Fanning Field

5h 37m1 stop Salt Lake City

$454Delta

Thu, Oct 8 - Wed, Oct 14

6:56 pm - 12:44 amIDA Idaho Falls Fanning Field-STL Lambert-St Louis

4h 48m1 stop Salt Lake City

12:00 pm - 10:10 pmSTL Lambert-St Louis-IDA Idaho Falls Fanning Field

11h 10m2 stops Atlanta Hartsfield-Jackson Salt Lake City

$499Delta

Thu, Oct 8 - Wed, Oct 14

6:00 am - 10:22 pmIDA Idaho Falls Fanning Field-STL Lambert-St Louis

15h 22m2 stops Dallas/Fort Worth Chicago O'Hare Intl

1:51 pm - 11:46 pmSTL Lambert-St Louis-IDA Idaho Falls Fanning Field

10h 55m2 stops Chicago O'Hare Intl Phoenix Sky Harbor Intl

$1,078American Airlines

Tue, Dec 22 - Tue, Dec 29

Save money when you book flights with momondo

Big names and deals

Search 100s of travel sites to compare prices.

Filter for what you want

Free Wi-Fi? Stopover? Instantly customize your results.

Trusted and free

We’re completely free to use - no hidden charges or fees.

Price Alerts

Not ready to book? to track prices.

Search flight deals

Alaska Airlines flights from Idaho Falls to St. Louis

Our best Alaska Airlines deals on Idaho Falls to St. Louis flight tickets

Alaska Airlines

Oct 31

IDA6:09 amIdaho Falls Fanning Field

8h 35m

1 stop

STL3:44 pmLambert-St Louis

Nov 4

STL7:00 amLambert-St Louis

9h 18m

1 stop

IDA3:18 pmIdaho Falls Fanning Field

$399

Alaska Airlines

Oct 31

IDA6:09 amIdaho Falls Fanning Field

8h 35m

1 stop

STL3:44 pmLambert-St Louis

Nov 4

STL6:00 amLambert-St Louis

10h 18m

1 stop

IDA3:18 pmIdaho Falls Fanning Field

$419

Alaska Airlines

Sep 26

IDA2:01 pmIdaho Falls Fanning Field

23h 20m

1 stop

STL2:21 pmLambert-St Louis

Sep 30

STL3:19 pmLambert-St Louis

8h 37m

1 stop

IDA10:56 pmIdaho Falls Fanning Field

$459

American Airlines flights from Idaho Falls to St. Louis

Our best American Airlines deals on Idaho Falls to St. Louis flight tickets

American Airlines

Sep 24

IDA1:58 pmIdaho Falls Fanning Field

5h 46m

1 stop

STL8:44 pmLambert-St Louis

Sep 27

STL5:43 amLambert-St Louis

7h 02m

1 stop

IDA11:45 amIdaho Falls Fanning Field

$444

American Airlines

Sep 16

IDA12:15 pmIdaho Falls Fanning Field

5h 52m

1 stop

STL7:07 pmLambert-St Louis

Sep 18

STL3:34 pmLambert-St Louis

6h 46m

1 stop

IDA9:20 pmIdaho Falls Fanning Field

$601

American Airlines

Dec 22

IDA6:00 amIdaho Falls Fanning Field

15h 22m

2 stops

STL10:22 pmLambert-St Louis

Dec 29

STL1:51 pmLambert-St Louis

10h 55m

2 stops

IDA11:46 pmIdaho Falls Fanning Field

$1,078

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

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

Sat 10/31

6:09 am-3:44 pm

1 stop8h 35m

Lambert-St Louis

Wed 11/4

6:00 am-3:18 pm

1 stop10h 18m

$419

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

$419

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

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

$444

Idaho FallsSt. Louis

IDA Idaho Falls Fanning Field - STL Lambert-St Louis

IDASTL

Idaho Falls Fanning Field

Thu 9/24

1:58 pm-8:44 pm

1 stop5h 46m

Lambert-St Louis

Sun 9/27

5:43 am-11:45 am

1 stop7h 02m

$444

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

7:30 am-3:38 pm

2 stops9h 08m

$444

Quickest round-trip

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

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

12:00 pm-10:10 pm

2 stops11h 10m

$499

Idaho FallsSt. Louis

IDA Idaho Falls Fanning Field - STL Lambert-St Louis

IDASTL

Idaho Falls Fanning Field

Tue 12/22

6:00 am-10:22 pm

2 stops15h 22m

Lambert-St Louis

Tue 12/29

1:51 pm-11:46 pm

2 stops10h 55m

$1,078

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 18 resultsSorted by cheapest first

How to get the cheapest flight ticket from Idaho Falls to St. Louis

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

Prices

Airlines

What is the cheapest month to fly to St. Louis?

In general, May is the cheapest month to fly from Idaho Falls to St. Louis. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $443. The month of June is another great option to travel to St. Louis, with average flight prices from Idaho Falls averaging around $466.

When to book flights from Idaho Falls to St. Louis

Are you open to changing your travel dates? Check out the ideal times to fly from Idaho Falls to St. Louis according to our flight data. Find out which month and days have the cheapest flights.

Estimated round-trip price

Cheap Idaho Falls to St. Louis (IDA to STL) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Idaho Falls to St. Louis

Best Price Found	$175
Fastest flight time	4h 48m
Direct flights	None

The best one-way flight to St. Louis from Idaho Falls in the past 72 hours is $175. The best round-trip flight deal from Idaho Falls to St. Louis found on momondo in the last 72 hours is $399.

The fastest flight from Idaho Falls to St. Louis takes 4h 48m

There are no direct flights from Idaho Falls to St. Louis. There are no popular flight routes from Idaho Falls to St. Louis.

Search flight deals

Frequently asked questions about flying from Idaho Falls to St. Louis

How far is Idaho Falls Fanning Field to Lambert-St Louis by plane?
Lambert-St Louis is 1181.2 mi away from Idaho Falls Fanning Field. Flights usually cover this in 4h 48m, depending on flying conditions and air traffic around both airports.
When did momondo last update prices for flights from Idaho Falls Fanning Field Airport to Lambert-St Louis Airport?
Prices for flights from Idaho Falls Fanning Field Airport to Lambert-St Louis Airport are updated daily.
How many operators does momondo search for flights from Idaho Falls Fanning Field Airport to Lambert-St Louis Airport?
The number of operators available for flights from Idaho Falls Fanning Field Airport to Lambert-St Louis Airport is 3 as of September 2026.
How old do you have to be to fly from Idaho Falls Fanning Field Airport to Lambert-St Louis Airport?
The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Idaho Falls Fanning Field Airport to Lambert-St Louis Airport.
What documentation or ID do you need to fly to Lambert-St Louis Airport?
The necessary travel and health documents for your Lambert-St Louis Airport trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.
What is the most popular airline from Idaho Falls to St. Louis?
momondo data reveals that the most frequently booked airline on the route from Idaho Falls to St. Louis is United Airlines, representing 67% of all bookings. The subsequent popular airlines are Delta at 18% and American Airlines at 14%.

Best airlines flying from Idaho Falls to St. Louis

Compare and see reviews for airlines that fly from Idaho Falls to St. Louis with momondo

Airline	Rating	Free Cancellation	Price
Delta	PriceFrom $164	Free Cancellation	Rating 7.8 8,564 reviews	Search Delta flights
American Airlines	PriceFrom $328	Free Cancellation	Rating 7.1 12,053 reviews	Search American Airlines flights
United Airlines	PriceFrom $421	Free Cancellation	Rating 7.4 10,213 reviews	Search United Airlines flights

St. Charles

Chesterfield

Fairview Heights

St. Peters

Maryland Heights

Alton

Collinsville

Florissant

Hermann

Clayton

O'Fallon

Farmington

Fenton

Festus

Edwardsville

Wentzville

Eureka

Litchfield

Grafton

Waterloo

Why use momondo?

Why should I use momondo to find a flight deal from Idaho Falls to St. Louis?

Finding the right flight to St. Louis from Idaho Falls is quick and easy when you have a range of options in front of you, from reputable agents and recognisable airlines. Options that can then be filtered down to find the best fit. That is what momondo does. We make finding flights to St. Louis quick and easy, saving you time and money.

Can I find flights from Idaho Falls to St. Louis with flexible booking policies on momondo?

Yes. All flights to St. Louis from Idaho Falls on momondo can be compared and filtered by various policies on offer, including flexible booking.

How can momondo help me find flights from Idaho Falls to St. Louis?

momondo helps you find the best flight between Idaho Falls and St. Louis by providing filters to narrow your choice of flights to those matching your criteria. You can select flights based on numerous factors such as price, departure and landing times, airport and airline.

I’m not ready to book a flight from Idaho Falls to St. Louis right now. Can momondo alert me if prices change?

Yes momondo offers price alerts on flights to St. Louis from Idaho Falls. After performing a search on this page you should be able to see the price alert set up feature. Simply provide a valid email address and momondo will instantly alert you when prices change.

An easier way to manage your St. Louis trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.

Start using Trips

Find my bookings

Get notified when prices go down

Daily price changes in your inbox - only with Price Alerts.

1 adult

Wed 10/14

Wed 10/21

Email me momondo's favorite deals

By creating a price alert you accept our terms of use and privacy policy.

Find better results for your trip to the United States

Nearby airports

Airlines

Cabin classes

Other United States destinations

Other flights from Idaho Falls

Complete your trip

Feeling lucky

Airports servicing Missouri

Branson Airport

Cape Girardeau Airport

Columbia Regional Airport

Kirksville Cannon Memorial Airport

Joplin Airport

Kansas City Airport

Springfield-Branson Airport

Fort Leonard Wood Waynesville Regional Airport

Cheap flights from Idaho Falls to St. Louis from $175

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Idaho Falls to St. Louis departing on 10/8. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

Find the cheapest flights from Idaho Falls to St. Louis

Cheap round-trip flights

Cheap one-way flights

Cheap last minute flights

Big names and deals

Big names and deals

Filter for what you want

Filter for what you want

Trusted and free

Trusted and free

Price Alerts

Price Alerts

Alaska Airlines flights from Idaho Falls to St. Louis

Our best Alaska Airlines deals on Idaho Falls to St. Louis flight tickets

American Airlines flights from Idaho Falls to St. Louis

Our best American Airlines deals on Idaho Falls to St. Louis flight tickets

momondo Fare Finder

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

See travel insights to St. Louis from

How to get the cheapest flight ticket from Idaho Falls to St. Louis

What is the cheapest month to fly to St. Louis?

What is the cheapest airline that flies from Idaho Falls Fanning Field to Lambert-St Louis?

What airlines fly to St. Louis?

When to book flights from Idaho Falls to St. Louis

Cheap Idaho Falls to St. Louis (IDA to STL) flight deals and tips

Best Price Found

Fastest flight time

Direct flights

Frequently asked questions about flying from Idaho Falls to St. Louis

Best airlines flying from Idaho Falls to St. Louis

Compare and see reviews for airlines that fly from Idaho Falls to St. Louis with momondo

Traveling to a place near St. Louis?

Why use momondo?

An easier way to manage your St. Louis trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.

Get notified when prices go down

Daily price changes in your inbox - only with Price Alerts.

Find better results for your trip to the United States

Airports servicing Missouri

Fly your favorite airline to St. Louis

Airlines are sorted and displayed according to clicks in the past 7 days on momondo

Cabin classes currently available on flights to St. Louis

List of cabin classes available on flights landing in St. Louis. Availability may vary depending on flight origin and airline.

Popular cities in the United States

Popular flights according to clicks in the last 7 days on momondo

Fly to other destinations from Idaho Falls

According to popular flight searches on momondo this year

Complete your trip to St. Louis

Explore popular destinations other users love

According to popular flight searches on momondo this year