Cheap flights from St. Louis to Idaho from $119

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from St. Louis to Idaho departing on 5/12. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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Find the cheapest flights from St. Louis to Idaho

Cheap round-trip flights

Enter your travel dates to find the best prices.
Frontier Logo
4:51 pm - 11:51 am
STL
-
BOI
20h 00m
1 stop
Frontier Logo
11:56 am - 1:09 pm
BOI
-
STL
24h 13m
1 stop
$222Frontier
Wed, Feb 25 - Sun, Mar 1
Delta Logo
6:29 am - 12:35 pm
STL
-
JAC
7h 06m
1 stop
Delta Logo
5:50 pm - 12:21 am
JAC
-
STL
5h 31m
1 stop
$257Delta
Wed, Mar 25 - Mon, Mar 30
Delta Logo
6:00 am - 1:30 pm
STL
-
JAC
8h 30m
1 stop
Delta Logo
5:50 pm - 12:21 am
JAC
-
STL
5h 31m
1 stop
$267Delta
Wed, Mar 25 - Mon, Mar 30
Alaska Airlines Logo
7:00 am - 12:29 pm
STL
-
GEG
7h 29m
1 stop
Alaska Airlines Logo
5:40 am - 1:51 pm
GEG
-
STL
6h 11m
1 stop
$272Alaska Airlines
Tue, Mar 3 - Wed, Mar 4
Delta Logo
6:00 am - 4:47 pm
STL
-
JAC
11h 47m
2 stops
Delta Logo
5:50 pm - 12:21 am
JAC
-
STL
5h 31m
1 stop
$272Delta
Wed, Mar 25 - Mon, Mar 30
United Airlines Logo
2:50 pm - 9:18 pm
STL
-
GEG
8h 28m
1 stop
United Airlines Logo
1:43 pm - 8:54 pm
GEG
-
STL
5h 11m
1 stop
$277United Airlines
Wed, Mar 25 - Wed, Apr 15
Alaska Airlines Logo
7:00 am - 3:29 pm
STL
-
BOI
9h 29m
1 stop
Alaska Airlines Logo
4:15 pm - 11:59 pm
BOI
-
STL
6h 44m
1 stop
$277Alaska Airlines
Tue, Mar 31 - Tue, Apr 7
Multiple Airlines Logo
7:00 am - 2:36 pm
STL
-
GEG
9h 36m
1 stop
Multiple Airlines Logo
12:40 pm - 10:02 pm
GEG
-
STL
7h 22m
1 stop
$289Multiple Airlines
Thu, Mar 5 - Sun, Mar 8
United Airlines Logo
6:05 pm - 10:43 pm
STL
-
BOI
5h 38m
1 stop
United Airlines Logo
2:40 pm - 8:41 pm
BOI
-
STL
5h 01m
1 stop
$301United Airlines
Fri, Mar 6 - Tue, Mar 10
Multiple Airlines Logo
6:38 am - 6:12 pm
STL
-
GEG
13h 34m
2 stops
Multiple Airlines Logo
12:40 pm - 10:02 pm
GEG
-
STL
7h 22m
1 stop
$326Multiple Airlines
Thu, Mar 5 - Sun, Mar 8

United Airlines flights from St. Louis to Idaho

Our best United Airlines deals on St. Louis to Idaho flight tickets
United Airlines
Mar 25
STL2:50 pmLambert-St Louis
8h 28m
1 stop
GEG9:18 pmSpokane
Apr 15
GEG1:43 pmSpokane
5h 11m
1 stop
STL8:54 pmLambert-St Louis
$277
United Airlines
Mar 6
STL6:05 pmLambert-St Louis
5h 38m
1 stop
BOI10:43 pmBoise Air Term. Gowen Fld
Mar 10
BOI2:40 pmBoise Air Term. Gowen Fld
5h 01m
1 stop
STL8:41 pmLambert-St Louis
$301
United Airlines
Feb 24
STL9:55 amLambert-St Louis
12h 04m
2 stops
JAC8:59 pmJackson Hole
Feb 28
JAC7:00 amJackson Hole
5h 14m
1 stop
STL1:14 pmLambert-St Louis
$304

Delta flights from St. Louis to Idaho

Our best Delta deals on St. Louis to Idaho flight tickets
Delta
Mar 25
STL6:29 amLambert-St Louis
7h 06m
1 stop
JAC12:35 pmJackson Hole
Mar 30
JAC5:50 pmJackson Hole
5h 31m
1 stop
STL12:21 amLambert-St Louis
$257
Delta
Mar 25
STL6:00 amLambert-St Louis
8h 30m
1 stop
JAC1:30 pmJackson Hole
Mar 30
JAC5:50 pmJackson Hole
5h 31m
1 stop
STL12:21 amLambert-St Louis
$267
Delta
Mar 25
STL6:00 amLambert-St Louis
11h 47m
2 stops
JAC4:47 pmJackson Hole
Mar 30
JAC5:50 pmJackson Hole
5h 31m
1 stop
STL12:21 amLambert-St Louis
$272

momondo Fare Finder

 
Customize your flight search to find flights from St. Louis to Idaho that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, momondo users made 832,500 searches. Data last updated February 12, 2026.
Use the filters below to find and compare flights from St. Louis to Idaho that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Wed 2/25

4:51 pm-11:51 am

1 stop20h 00m

Boise Air Term. Gowen Fld

Sun 3/1

11:56 am-1:09 pm

1 stop24h 13m

$222

St. LouisJackson

STL - JAC

STLJAC

Lambert-St Louis

Wed 3/25

6:29 am-12:35 pm

1 stop7h 06m

Jackson Hole

Mon 3/30

5:50 pm-12:21 am

1 stop5h 31m

$257

St. LouisJackson

STL - JAC

STLJAC

Lambert-St Louis

Wed 3/25

6:00 am-1:30 pm

1 stop8h 30m

Jackson Hole

Mon 3/30

5:50 pm-12:21 am

1 stop5h 31m

$267

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Tue 3/3

7:00 am-12:29 pm

1 stop7h 29m

Spokane

Wed 3/4

5:40 am-1:51 pm

1 stop6h 11m

$272

St. LouisJackson

STL - JAC

STLJAC

Lambert-St Louis

Wed 3/25

6:00 am-4:47 pm

2 stops11h 47m

Jackson Hole

Mon 3/30

5:50 pm-12:21 am

1 stop5h 31m

$272

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Wed 3/25

2:50 pm-9:18 pm

1 stop8h 28m

Spokane

Wed 4/15

1:43 pm-8:54 pm

1 stop5h 11m

$277

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Tue 3/31

7:00 am-3:29 pm

1 stop9h 29m

Boise Air Term. Gowen Fld

Tue 4/7

4:15 pm-11:59 pm

1 stop6h 44m

$277

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Thu 3/5

7:00 am-2:36 pm

1 stop9h 36m

Spokane

Sun 3/8

12:40 pm-10:02 pm

1 stop7h 22m

$289

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Fri 3/6

6:05 pm-10:43 pm

1 stop5h 38m

Boise Air Term. Gowen Fld

Tue 3/10

2:40 pm-8:41 pm

1 stop5h 01m

$301

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Thu 3/5

6:38 am-6:12 pm

2 stops13h 34m

Spokane

Sun 3/8

12:40 pm-10:02 pm

1 stop7h 22m

$326

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first
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See travel insights to Idaho from

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

What is the cheapest month to fly to Idaho?

In general, November 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 $358. If you don’t want to visit Idaho in November, then you should wait until January to fly from St. Louis, when ticket prices are also cheap, with an average price of $359.

How far in advance should I book a flight to Idaho?

You are more likely to see cheaper flights to Idaho from St. Louis when booking weeks ahead of your departure date. In general, you can expect to find flights to Idaho for around $426 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Idaho from St. Louis for as low as $304 on momondo.

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 59m

Direct flights

None
The fastest flight from St. Louis to Idaho takes 4h 59m
There are no direct flights from St. Louis to Idaho. There are no popular flight routes 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?

  • 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
DeltaPriceFrom $163Free CancellationRating
7.9
8,180 reviews
Search Delta flights
American AirlinesPriceFrom $186Free CancellationRating
7.2
11,271 reviews
Search American Airlines flights
United AirlinesPriceFrom $290Free CancellationRating
7.4
9,279 reviews
Search United Airlines flights
SouthwestPriceFrom $296Free CancellationRating
8.0
4,280 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.

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1 adult
Sat 3/14
Sat 3/21

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