What airlines fly to Idaho?

United Airlines, Delta and Southwest 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 53% 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, Delta, and United Airlines 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 4 operators available for flights from Lambert-St Louis Airport to Idaho as of November 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.

$169 Cheap Flights from St. Louis to Idaho in 2026/27

Discover deals from 900+ travel sites with momondo.

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.

5:45 pm - 4:48 pmSTL Lambert-St Louis-BOI Boise Air Term. Gowen Fld

24h 03m1 stop Las Vegas Harry Reid Intl

5:33 pm - 4:42 pmBOI Boise Air Term. Gowen Fld-STL Lambert-St Louis

22h 09m1 stop Las Vegas Harry Reid Intl

$334Frontier

Thu, Dec 17 - Mon, Dec 21

2:28 pm - 11:11 pmSTL Lambert-St Louis-IDA Idaho Falls Fanning Field

9h 43m1 stop Phoenix Sky Harbor Intl

6:26 am - 2:05 pmIDA Idaho Falls Fanning Field-STL Lambert-St Louis

6h 39m1 stop Dallas/Fort Worth

$359American Airlines

Wed, Jan 20 - Tue, Jan 26

2:16 pm - 6:19 pmSTL Lambert-St Louis-IDA Idaho Falls Fanning Field

5h 03m1 stop Salt Lake City

5:25 am - 1:26 pmIDA Idaho Falls Fanning Field-STL Lambert-St Louis

7h 01m1 stop Salt Lake City

$359Delta

Thu, Jan 21 - Fri, Jan 29

7:00 am - 12:24 pmSTL Lambert-St Louis-IDA Idaho Falls Fanning Field

6h 24m1 stop Salt Lake City

5:25 am - 1:26 pmIDA Idaho Falls Fanning Field-STL Lambert-St Louis

7h 01m1 stop Salt Lake City

$359Delta

Fri, Jan 22 - Fri, Jan 29

2:54 pm - 9:49 pmSTL Lambert-St Louis-IDA Idaho Falls Fanning Field

7h 55m1 stop Dallas/Fort Worth

6:51 am - 7:58 pmIDA Idaho Falls Fanning Field-STL Lambert-St Louis

12h 07m2 stops Phoenix Sky Harbor Intl Chicago O'Hare Intl

$364American Airlines

Wed, Dec 2 - Wed, Dec 9

5:06 pm - 11:15 pmSTL Lambert-St Louis-BOI Boise Air Term. Gowen Fld

7h 09m1 stop Chicago O'Hare Intl

6:25 am - 1:13 pmBOI Boise Air Term. Gowen Fld-STL Lambert-St Louis

5h 48m1 stop Denver Intl

$369United Airlines

Sat, Feb 6 - Sat, Feb 13

6:04 am - 12:21 pmSTL Lambert-St Louis-BOI Boise Air Term. Gowen Fld

7h 17m1 stop Seattle/Tacoma Intl

2:05 pm - 11:59 pmBOI Boise Air Term. Gowen Fld-STL Lambert-St Louis

8h 54m1 stop Seattle/Tacoma Intl

$369Alaska Airlines

Sat, Dec 12 - Mon, Dec 14

10:45 am - 9:33 pmSTL Lambert-St Louis-BOI Boise Air Term. Gowen Fld

11h 48m2 stops Chicago O'Hare Intl Denver Intl

2:35 pm - 8:54 pmBOI Boise Air Term. Gowen Fld-STL Lambert-St Louis

5h 19m1 stop Denver Intl

$374United Airlines

Sat, Feb 6 - Sat, Feb 13

8:25 am - 2:15 pmSTL Lambert-St Louis-BOI Boise Air Term. Gowen Fld

6h 50m1 stop San Diego

5:45 am - 12:30 pmBOI Boise Air Term. Gowen Fld-STL Lambert-St Louis

5h 45m1 stop Phoenix Sky Harbor Intl

$445Southwest

Tue, Nov 17 - Fri, Dec 4

6:20 am - 3:10 pmSTL Lambert-St Louis-BOI Boise Air Term. Gowen Fld

9h 50m2 stops Chicago Midway Denver Intl

5:45 am - 12:30 pmBOI Boise Air Term. Gowen Fld-STL Lambert-St Louis

5h 45m1 stop Phoenix Sky Harbor Intl

$455Southwest

Tue, Nov 17 - Fri, Dec 4

Cheap last minute flights

Enter your travel dates to find the best prices.

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

10h 18m1 stop Seattle/Tacoma Intl

1:53 pm - 11:59 pmIDA Idaho Falls Fanning Field-STL Lambert-St Louis

9h 06m1 stop Seattle/Tacoma Intl

$509Alaska Airlines

Tue, Nov 10 - Sun, Nov 15

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

10h 18m1 stop Seattle/Tacoma Intl

1:53 pm - 11:59 pmIDA Idaho Falls Fanning Field-STL Lambert-St Louis

9h 06m1 stop Seattle/Tacoma Intl

$519Alaska Airlines

Tue, Nov 10 - Sun, Nov 15

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

10h 18m1 stop Seattle/Tacoma Intl

1:53 pm - 11:59 pmIDA Idaho Falls Fanning Field-STL Lambert-St Louis

9h 06m1 stop Seattle/Tacoma Intl

$539Alaska Airlines

Wed, Nov 11 - Thu, Nov 12

5:00 am - 1:28 pmSTL Lambert-St Louis-IDA Idaho Falls Fanning Field

9h 28m2 stops Chicago O'Hare Intl Denver Intl

10:35 am - 4:56 pmIDA Idaho Falls Fanning Field-STL Lambert-St Louis

5h 21m1 stop Denver Intl

$569United Airlines

Tue, Nov 10 - Sun, Nov 15

5:00 am - 1:28 pmSTL Lambert-St Louis-IDA Idaho Falls Fanning Field

9h 28m2 stops Chicago O'Hare Intl Denver Intl

2:35 pm - 9:01 pmIDA Idaho Falls Fanning Field-STL Lambert-St Louis

5h 26m1 stop Denver Intl

$579United Airlines

Tue, Nov 10 - Sun, Nov 15

1:20 pm - 10:59 pmSTL Lambert-St Louis-IDA Idaho Falls Fanning Field

10h 39m2 stops Chicago O'Hare Intl Phoenix Sky Harbor Intl

1:35 pm - 10:39 pmIDA Idaho Falls Fanning Field-STL Lambert-St Louis

8h 04m1 stop Dallas/Fort Worth

$730American Airlines

Wed, Nov 11 - Thu, Nov 12

10:53 am - 9:09 pmSTL Lambert-St Louis-IDA Idaho Falls Fanning Field

11h 16m2 stops Chicago O'Hare Intl Denver Intl

10:35 am - 11:24 pmIDA Idaho Falls Fanning Field-STL Lambert-St Louis

11h 49m2 stops Denver Intl Chicago O'Hare Intl

$919United Airlines

Wed, Nov 11 - Thu, Nov 12

2:21 pm - 9:59 pmSTL Lambert-St Louis-IDA Idaho Falls Fanning Field

8h 38m2 stops Detroit Metropolitan Wayne County Salt Lake City

1:11 pm - 11:22 pmIDA Idaho Falls Fanning Field-STL Lambert-St Louis

9h 11m2 stops Salt Lake City Minneapolis St Paul

$942Delta

Tue, Nov 10 - Sun, Nov 15

11:35 am - 10:59 pmSTL Lambert-St Louis-IDA Idaho Falls Fanning Field

12h 24m2 stops Chicago O'Hare Intl Phoenix Sky Harbor Intl

1:35 pm - 11:55 pmIDA Idaho Falls Fanning Field-STL Lambert-St Louis

9h 20m2 stops Dallas/Fort Worth Chicago O'Hare Intl

$985American Airlines

Tue, Nov 10 - Sun, Nov 15

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Delta flights from St. Louis to Idaho

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

Delta

Jan 28

STL2:16 pmLambert-St Louis

5h 03m

1 stop

IDA6:19 pmIdaho Falls Fanning Field

Feb 2

IDA5:25 amIdaho Falls Fanning Field

7h 01m

1 stop

STL1:26 pmLambert-St Louis

$359

Delta

Jan 20

STL7:00 amLambert-St Louis

6h 24m

1 stop

IDA12:24 pmIdaho Falls Fanning Field

Jan 28

IDA6:59 pmIdaho Falls Fanning Field

13h 18m

2 stops

STL9:17 amLambert-St Louis

$364

Delta

Jan 19

STL12:00 pmLambert-St Louis

11h 42m

2 stops

IDA10:42 pmIdaho Falls Fanning Field

Jan 29

IDA1:10 pmIdaho Falls Fanning Field

9h 16m

2 stops

STL11:26 pmLambert-St Louis

$369

American Airlines flights from St. Louis to Idaho

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

American Airlines

Dec 5

STL2:31 pmLambert-St Louis

9h 27m

1 stop

BOI10:58 pmBoise Air Term. Gowen Fld

Dec 12

BOI6:40 amBoise Air Term. Gowen Fld

6h 15m

1 stop

STL1:55 pmLambert-St Louis

$369

American Airlines

Dec 5

STL10:25 amLambert-St Louis

10h 06m

2 stops

BOI7:31 pmBoise Air Term. Gowen Fld

Dec 12

BOI2:42 pmBoise Air Term. Gowen Fld

6h 38m

1 stop

STL10:20 pmLambert-St Louis

$374

American Airlines

Dec 5

STL10:25 amLambert-St Louis

10h 06m

2 stops

BOI7:31 pmBoise Air Term. Gowen Fld

Dec 12

BOI2:11 pmBoise Air Term. Gowen Fld

8h 51m

2 stops

STL12:02 amLambert-St Louis

$380

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

St. LouisBoise

STL Lambert-St Louis - BOI Boise Air Term. Gowen Fld

STLBOI

Lambert-St Louis

Thu 12/17

5:45 pm-4:48 pm

1 stop24h 03m

Boise Air Term. Gowen Fld

Mon 12/21

5:33 pm-4:42 pm

1 stop22h 09m

$334

St. LouisIdaho Falls

STL Lambert-St Louis - IDA Idaho Falls Fanning Field

STLIDA

Lambert-St Louis

Wed 1/20

2:28 pm-11:11 pm

1 stop9h 43m

Idaho Falls Fanning Field

Tue 1/26

6:26 am-2:05 pm

1 stop6h 39m

$359

Quickest round-trip

St. LouisIdaho Falls

STL Lambert-St Louis - IDA Idaho Falls Fanning Field

STLIDA

Lambert-St Louis

Thu 1/21

2:16 pm-6:19 pm

1 stop5h 03m

Idaho Falls Fanning Field

Fri 1/29

5:25 am-1:26 pm

1 stop7h 01m

$359

St. LouisIdaho Falls

STL Lambert-St Louis - IDA Idaho Falls Fanning Field

STLIDA

Lambert-St Louis

Fri 1/22

7:00 am-12:24 pm

1 stop6h 24m

Idaho Falls Fanning Field

Fri 1/29

5:25 am-1:26 pm

1 stop7h 01m

$359

St. LouisIdaho Falls

STL Lambert-St Louis - IDA Idaho Falls Fanning Field

STLIDA

Lambert-St Louis

Wed 12/2

2:54 pm-9:49 pm

1 stop7h 55m

Idaho Falls Fanning Field

Wed 12/9

6:51 am-7:58 pm

2 stops12h 07m

$364

St. LouisBoise

STL Lambert-St Louis - BOI Boise Air Term. Gowen Fld

STLBOI

Lambert-St Louis

Sat 2/6

5:06 pm-11:15 pm

1 stop7h 09m

Boise Air Term. Gowen Fld

Sat 2/13

6:25 am-1:13 pm

1 stop5h 48m

$369

St. LouisBoise

STL Lambert-St Louis - BOI Boise Air Term. Gowen Fld

STLBOI

Lambert-St Louis

Sat 12/12

6:04 am-12:21 pm

1 stop7h 17m

Boise Air Term. Gowen Fld

Mon 12/14

2:05 pm-11:59 pm

1 stop8h 54m

$369

St. LouisBoise

STL Lambert-St Louis - BOI Boise Air Term. Gowen Fld

STLBOI

Lambert-St Louis

Sat 2/6

10:45 am-9:33 pm

2 stops11h 48m

Boise Air Term. Gowen Fld

Sat 2/13

2:35 pm-8:54 pm

1 stop5h 19m

$374

St. LouisBoise

STL Lambert-St Louis - BOI Boise Air Term. Gowen Fld

STLBOI

Lambert-St Louis

Tue 11/17

8:25 am-2:15 pm

1 stop6h 50m

Boise Air Term. Gowen Fld

Fri 12/4

5:45 am-12:30 pm

1 stop5h 45m

$445

St. LouisBoise

STL Lambert-St Louis - BOI Boise Air Term. Gowen Fld

STLBOI

Lambert-St Louis

Tue 11/17

6:20 am-3:10 pm

2 stops9h 50m

Boise Air Term. Gowen Fld

Fri 12/4

5:45 am-12:30 pm

1 stop5h 45m

$455

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, January 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 $359. If you don’t want to visit Idaho in January, then you should wait until November to fly from St. Louis, when ticket prices are also cheap, with an average price of $408.

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

Best Price Found	$169
Fastest flight time	5h 30m
Direct flights	None

The best one-way flight to Idaho from St. Louis in the past 72 hours is $169. The best round-trip flight deal from St. Louis to Idaho found on momondo in the last 72 hours is $334.

The fastest flight from St. Louis to Idaho takes 5h 30m

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 4 operators available for flights from Lambert-St Louis Airport to Idaho as of November 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 $207	Free Cancellation	Rating 7.0 12,230 reviews	Search American Airlines flights
Delta	PriceFrom $237	Free Cancellation	Rating 7.8 8,703 reviews	Search Delta flights
United Airlines	PriceFrom $290	Free Cancellation	Rating 7.3 10,472 reviews	Search United Airlines flights
Southwest	PriceFrom $343	Free Cancellation	Rating 8.0 4,215 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.