What airlines fly to Idaho?

United Airlines, Southwest and Delta are the top three most popular airlines that fly to Idaho from St. Louis according to our data. United Airlines is the first choice among our users, with 48% of people opting to fly with this airline when traveling to Idaho. Keep in mind that there are 4 different airlines that fly to Idaho on a routine basis, so you have a few additional options to choose from.

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

Frontier, Southwest, and Delta are the most popular carriers operating from Lambert-St Louis to Idaho

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

Prices for flights from Lambert-St Louis Airport to Idaho refresh daily.

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

There are 5 operators available for flights from Lambert-St Louis Airport to Idaho as of May 2026.

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

Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Lambert-St Louis Airport to Idaho.

What documentation or ID do you need to fly to Idaho?

The travel and health documents you'll need for your trip to Idaho may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Idaho. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

$146 Cheap Flights from St. Louis to Idaho in 2026

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Find the cheapest flights from St. Louis to Idaho

Round-trip

One-way

Last minute

Cheap round-trip flights

Enter your travel dates to find the best prices.

6:59 pm - 10:35 pm

STL

GEG

5h 36m

1 stop

5:20 pm - 12:34 am

GEG

STL

5h 14m

1 stop

$249Delta

Tue, Sep 8 - Tue, Sep 15

5:59 am - 1:37 pm

STL

GEG

9h 38m

1 stop

6:30 am - 5:37 pm

GEG

STL

9h 07m

1 stop

$285American Airlines

Thu, Aug 20 - Tue, Aug 25

5:59 am - 1:37 pm

STL

GEG

9h 38m

1 stop

6:30 am - 6:04 pm

GEG

STL

9h 34m

2 stops

$314American Airlines

Tue, Sep 8 - Tue, Sep 15

8:00 am - 12:12 pm

STL

GEG

6h 12m

1 stop

5:30 am - 1:34 pm

GEG

STL

6h 04m

1 stop

$316Delta

Wed, Jul 29 - Wed, Aug 12

7:00 am - 3:17 pm

STL

IDA

9h 17m

1 stop

6:04 am - 2:15 pm

IDA

STL

7h 11m

1 stop

$319Alaska Airlines

Sat, Nov 14 - Wed, Nov 18

7:38 pm - 12:30 pm

STL

BOI

17h 52m

1 stop

1:24 pm - 7:23 pm

BOI

STL

4h 59m

1 stop

$330Frontier

Mon, Jun 29 - Tue, Jul 7

6:00 am - 1:23 pm

STL

GEG

9h 23m

1 stop

8:31 am - 10:59 pm

GEG

STL

12h 28m

2 stops

$354Alaska Airlines

Tue, Aug 25 - Wed, Aug 26

8:08 pm - 12:29 pm

STL

BOI

17h 21m

1 stop

1:24 pm - 7:23 pm

BOI

STL

4h 59m

1 stop

$360Frontier

Wed, Jul 15 - Tue, Jul 21

5:10 am - 10:03 am

STL

JAC

5h 53m

1 stop

1:45 pm - 10:59 pm

JAC

STL

8h 14m

2 stops

$364United Airlines

Thu, Oct 15 - Tue, Oct 20

5:10 am - 9:50 am

STL

IDA

5h 40m

1 stop

5:54 pm - 11:57 pm

IDA

STL

5h 03m

1 stop

$369United Airlines

Sat, Jun 13 - Wed, Jun 17

Frontier flights from St. Louis to Idaho

Our best Frontier deals on St. Louis to Idaho flight tickets

Frontier

Jun 29

STL7:38 pmLambert-St Louis

17h 52m

1 stop

BOI12:30 pmBoise Air Term. Gowen Fld

Jul 7

BOI1:24 pmBoise Air Term. Gowen Fld

4h 59m

1 stop

STL7:23 pmLambert-St Louis

$330

Frontier

Jul 15

STL8:08 pmLambert-St Louis

17h 21m

1 stop

BOI12:29 pmBoise Air Term. Gowen Fld

Jul 21

BOI1:24 pmBoise Air Term. Gowen Fld

4h 59m

1 stop

STL7:23 pmLambert-St Louis

$360

Delta flights from St. Louis to Idaho

Our best Delta deals on St. Louis to Idaho flight tickets

Delta

Sep 8

STL6:59 pmLambert-St Louis

5h 36m

1 stop

GEG10:35 pmSpokane

Sep 15

GEG5:20 pmSpokane

5h 14m

1 stop

STL12:34 amLambert-St Louis

$249

Delta

Jul 29

STL8:00 amLambert-St Louis

6h 12m

1 stop

GEG12:12 pmSpokane

Aug 12

GEG5:30 amSpokane

6h 04m

1 stop

STL1:34 pmLambert-St Louis

$316

Delta

Sep 18

STL2:27 pmLambert-St Louis

5h 47m

1 stop

GEG6:14 pmSpokane

Sep 23

GEG7:00 amSpokane

7h 53m

1 stop

STL4:53 pmLambert-St Louis

$337

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Tue 9/8

6:59 pm-10:35 pm

1 stop5h 36m

Spokane

Tue 9/15

5:20 pm-12:34 am

1 stop5h 14m

$249

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Thu 8/20

5:59 am-1:37 pm

1 stop9h 38m

Spokane

Tue 8/25

6:30 am-5:37 pm

1 stop9h 07m

$285

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Tue 9/8

5:59 am-1:37 pm

1 stop9h 38m

Spokane

Tue 9/15

6:30 am-6:04 pm

2 stops9h 34m

$314

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Wed 7/29

8:00 am-12:12 pm

1 stop6h 12m

Spokane

Wed 8/12

5:30 am-1:34 pm

1 stop6h 04m

$316

St. LouisIdaho Falls

STL - IDA

STLIDA

Lambert-St Louis

Sat 11/14

7:00 am-3:17 pm

1 stop9h 17m

Idaho Falls Fanning Field

Wed 11/18

6:04 am-2:15 pm

1 stop7h 11m

$319

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Mon 6/29

7:38 pm-12:30 pm

1 stop17h 52m

Boise Air Term. Gowen Fld

Tue 7/7

1:24 pm-7:23 pm

1 stop4h 59m

$330

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Tue 8/25

6:00 am-1:23 pm

1 stop9h 23m

Spokane

Wed 8/26

8:31 am-10:59 pm

2 stops12h 28m

$354

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Wed 7/15

8:08 pm-12:29 pm

1 stop17h 21m

Boise Air Term. Gowen Fld

Tue 7/21

1:24 pm-7:23 pm

1 stop4h 59m

$360

St. LouisJackson

STL - JAC

STLJAC

Lambert-St Louis

Thu 10/15

5:10 am-10:03 am

1 stop5h 53m

Jackson Hole

Tue 10/20

1:45 pm-10:59 pm

2 stops8h 14m

$364

Quickest round-trip

St. LouisIdaho Falls

STL - IDA

STLIDA

Lambert-St Louis

Sat 6/13

5:10 am-9:50 am

1 stop5h 40m

Idaho Falls Fanning Field

Wed 6/17

5:54 pm-11:57 pm

1 stop5h 03m

$369

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first

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

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 Idaho?

In general, September is the cheapest month to fly from St. Louis to Idaho. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $186. If you don’t want to visit Idaho in September, then you should wait until August to fly from St. Louis, when ticket prices are also cheap, with an average price of $192.

Cheap St. Louis to Idaho flight deals and tips

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

Fastest flight time	4h 52m
Direct flights	None

The fastest flight from St. Louis to Idaho takes 4h 52m

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

Search flight deals

Frequently asked questions about flying from St. Louis to Idaho

When did momondo last update prices for flights from Lambert-St Louis Airport to Idaho?
Prices for flights from Lambert-St Louis Airport to Idaho refresh daily.
How many operators does momondo search for flights from Lambert-St Louis Airport to Idaho?
There are 5 operators available for flights from Lambert-St Louis Airport to Idaho as of May 2026.
How old do you have to be to fly from Lambert-St Louis Airport to Idaho?
Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Lambert-St Louis Airport to Idaho.
What documentation or ID do you need to fly to Idaho?
The travel and health documents you'll need for your trip to Idaho may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Idaho. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

Best airlines flying from St. Louis to Idaho

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

Airline	Rating	Free Cancellation	Price
American Airlines	PriceFrom $186	Free Cancellation	Rating 7.1 11,642 reviews	Search American Airlines flights
Delta	PriceFrom $240	Free Cancellation	Rating 7.9 8,412 reviews	Search Delta flights
United Airlines	PriceFrom $290	Free Cancellation	Rating 7.4 9,768 reviews	Search United Airlines flights
Southwest	PriceFrom $296	Free Cancellation	Rating 8.0 4,261 reviews	Search Southwest flights

Why use momondo?

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

To find the flight that best suits your needs, momondo gathers a range of flights from a large pool of different airlines and agents; you can then use our insights and filters to find and book the right flight to Idaho from St. Louis.

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

momondo does allow users to show only those flights to Idaho from St. Louis which offer a flexible booking policy as well as other useful filters and features.

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

momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from St. Louis to Idaho.

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

Yes momondo offers price alerts on flights to Idaho from St. Louis. 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.