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Idaho

$123+ Cheap flights from St. Louis (STL) to Idaho

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 12/12. Fares are subject to change and may not be available on all flights or dates of travel.
STL — BOI
Dec 6 — Dec 131
Sat 12/6
Sat 12/13
1 adult, Economy
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Find flight deals from St. Louis to Idaho

Cheapest flights from St. Louis to Idaho
Explore the most affordable flight options available from St. Louis to Idaho. Find the lowest fares from popular airlines and budget airlines, with prices last updated on November 6, 2025.

This Kiwi.com deal was found by Cheapflights users on 11/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/209:54 pmSTL - BOI
1 stop18h 58mMultiple Airlines
Mon 11/2410:45 pmBOI - STL
1 stop21h 24mMultiple Airlines
Deal found 11/5$230
This Delta deal was found by Cheapflights users on 11/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/52:20 pmSTL - GEG
2 stops10h 29mDelta
Tue 12/91:10 pmGEG - STL
2 stops9h 51mDelta
Deal found 11/5$236
This Delta deal was found by Cheapflights users on 11/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/186:00 amSTL - GEG
2 stops10h 55mDelta
Fri 1/91:20 pmGEG - STL
2 stops8h 05mDelta
Deal found 11/6$256
This Delta deal was found by Cheapflights users on 11/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/2510:45 amSTL - GEG
2 stops14h 05mDelta
Wed 12/36:05 amGEG - STL
2 stops11h 05mDelta
Deal found 11/5$276
This Kiwi.com deal was found by Cheapflights users on 11/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/247:43 pmSTL - BOI
1 stop17h 10mMultiple Airlines
Mon 12/13:17 pmBOI - STL
2 stops41h 57mMultiple Airlines
Deal found 11/6$298
This Delta deal was found by Cheapflights users on 11/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/166:30 amSTL - BOI
2 stops13h 21mDelta
Tue 12/303:23 pmBOI - STL
1 stop5h 53mDelta
Deal found 11/5$307
This Delta deal was found by Cheapflights users on 11/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/52:20 pmSTL - GEG
2 stops10h 29mDelta
Mon 12/152:15 pmGEG - STL
1 stop7h 14mDelta
Deal found 11/6$309
This Delta deal was found by Cheapflights users on 11/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/96:30 amSTL - JAC
1 stop6h 30mDelta
Tue 12/1612:55 pmJAC - STL
1 stop5h 15mDelta
Deal found 11/6$309
This Alaska Airlines deal was found by Cheapflights users on 11/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/57:00 amSTL - GEG
1 stop19h 24mAlaska Airlines
Tue 12/98:47 pmGEG - STL
1 stop15h 40mAlaska Airlines
Deal found 11/5$314
This Kiwi.com deal was found by Cheapflights users on 11/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/245:19 pmSTL - BOI
2 stops19h 24mFrontier
Sun 12/2812:38 pmBOI - STL
1 stop20h 24mFrontier
Deal found 11/5$317
This Alaska Airlines deal was found by Cheapflights users on 11/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/57:00 amSTL - GEG
1 stop18h 14mAlaska Airlines
Mon 12/157:47 pmGEG - STL
1 stop16h 40mAlaska Airlines
Deal found 11/6$333
This Delta deal was found by Cheapflights users on 11/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/202:21 pmSTL - JAC
1 stop8h 08mDelta
Mon 11/245:50 pmJAC - STL
1 stop5h 56mDelta
Deal found 11/5$339

Cheap flight deals from St. Louis to Idaho

Keep the following information in mind while searching for St. Louis to Idaho flight deals. Data was last updated November 6, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$230
(Kiwi.com)

One-way from

$123
(Kiwi.com)

Popular in

December

Cheapest in

April

Average price

$387
Provider with most accurate pricing for Lambert-St Louis-Boise Air Term. Gowen Fld flight deals.
Search Deals
Provider most trusted by Cheapflights users for Lambert-St Louis-Boise Air Term. Gowen Fld flights.
Search Deals
From Lambert-St Louis to Idaho
Search Deals
One-way flight from Lambert-St Louis to Idaho
Search Deals
Highest demand for flights based on searches. 0% potential increase in price ($4 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($5 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in November 2025
Search Deals

Cheapflights 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, Cheapflights users made 2,558,603 searches. Data last updated November 6, 2025.
Use the filters below to find and compare flights from St. Louis to Idaho that are best for you.

Fly from

St. Louis

Fly to

Idaho

Route

Depart

Return

Price

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Fri 12/5

2:20 pm-10:49 pm

2 stops10h 29m

Spokane

Tue 12/9

1:10 pm-1:01 am

2 stops9h 51m

$236

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Fri 12/5

2:38 pm-12:11 am

2 stops11h 33m

Spokane

Mon 12/15

7:35 pm-9:50 am

2 stops12h 15m

$236

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Thu 12/18

6:00 am-2:55 pm

2 stops10h 55m

Spokane

Fri 1/9

1:20 pm-11:25 pm

2 stops8h 05m

$256

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Tue 11/25

10:45 am-10:50 pm

2 stops14h 05m

Spokane

Wed 12/3

6:05 am-7:10 pm

2 stops11h 05m

$276

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Thu 11/20

3:14 pm-3:52 pm

2 stops25h 38m

Boise Air Term. Gowen Fld

Mon 11/24

10:45 pm-9:09 pm

1 stop21h 24m

$289

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Fri 1/16

6:35 am-6:47 pm

2 stops14h 12m

Spokane

Sun 1/18

2:00 pm-11:25 pm

1 stop7h 25m

$293

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Tue 12/16

6:30 am-6:51 pm

2 stops13h 21m

Boise Air Term. Gowen Fld

Tue 12/30

3:23 pm-10:16 pm

1 stop5h 53m

$307

St. LouisJackson

STL - JAC

STLJAC

Lambert-St Louis

Sat 4/25

7:30 am-12:09 pm

1 stop5h 39m

Jackson Hole

Wed 4/29

5:30 pm-12:36 am

1 stop6h 06m

$309

St. LouisJackson

STL - JAC

STLJAC

Lambert-St Louis

Thu 1/8

7:00 am-12:00 pm

1 stop6h 00m

Jackson Hole

Tue 1/13

12:58 pm-9:35 pm

1 stop7h 37m

$309

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Fri 12/5

7:00 am-12:24 am

1 stop19h 24m

Spokane

Tue 12/9

8:47 pm-2:27 pm

1 stop15h 40m

$314

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/4

Showing 1-10 of 48 results
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Best time to book a flight from St. Louis to Idaho

Have a flexible travel schedule? Discover the best time to fly to Idaho 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

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

Currently, September is the cheapest month in which you can book a flight from St. Louis to Idaho (average of $186). Flying from St. Louis to Idaho in January is currently the most expensive (average of $300). 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.

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

Find hourly flight availability from St. Louis to Idaho. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated November 6, 2025.

It’s optimal to fly from St. Louis to Idaho in the evening. By choosing this option you can save up to 15% on the cost of your flight, compared to a flight in the morning.

Reviews of airlines servicing Idaho

Get insights into the airlines that provide service to Idaho. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Idaho. Reviews last updated November 6, 2025.
Peruse reviews from past customers who have flown with Southwest, Delta, and United Airlines from St. Louis to Idaho to help guide your decision. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,241 reviews

Crew

8.6

Food

7.0

Entertainment

7.5

Boarding

8.1

Comfort

8.0

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Southwest
8.0
Very good
4,241 reviews
Southwest
8.0
Very good
4,241 reviews

Crew

8.6

Food

7.0

Entertainment

7.5

Boarding

8.1

Comfort

8.0

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Delta
7.9
Good
8,001 reviews
Southwest
8.0
Very good
4,241 reviews

Crew

8.6

Food

7.0

Entertainment

7.5

Boarding

8.1

Comfort

8.0

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
United Airlines
7.4
Good
9,007 reviews
Southwest
8.0
Very good
4,241 reviews

Crew

8.6

Food

7.0

Entertainment

7.5

Boarding

8.1

Comfort

8.0

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
American Airlines
7.2
Good
11,040 reviews
Southwest
8.0
Very good
4,241 reviews

Crew

8.6

Food

7.0

Entertainment

7.5

Boarding

8.1

Comfort

8.0

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Idaho. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly from for flights from St. Louis to Idaho?

    For a flight from St. Louis to Idaho, you will be flying from Lambert-St Louis. Lambert-St Louis (STL) is just 12.7 mi from the center of the city.

  • How long is the flight from St. Louis to Idaho?

    For as low as $372, Delta can have you in Idaho from St. Louis in 9h 09m. Airlines will cover a distance of 1171 mi. This flight may include one or multiple stops.

  • What are the cheapest airlines to fly from St. Louis to Idaho one-way?

    The cheapest airlines for a one-way flight from St. Louis to Idaho are Delta ($148), United Airlines ($170), and Alaska Airlines ($235).

  • What are the most popular routes from St. Louis to Idaho?

    The most popular route from St. Louis to Idaho is Lambert-St Louis - Jackson Hole. You may also consider Lambert-St Louis - Spokane or Lambert-St Louis - Idaho Falls Fanning Field.

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

    Yes. In addition to deals on St. Louis to Idaho flights, Cheapflights offers vacation packages that include both flights and hotel.

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

    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.

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

    Yes. Cheapflights offers flight deals from St. Louis to Idaho 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?

    Currently, September is the cheapest month in which you can book a flight from St. Louis to Idaho (average of $186). Flying from St. Louis to Idaho in January is currently the most expensive (average of $300). 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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Alternative routes for St. Louis to Idaho

See prices for flight routes from nearby airports that may be better suited for you.
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Top 4 airlines flying from St. Louis to Idaho

Discover the top 4 airlines that operate flights from St. Louis to Idaho. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated November 6, 2025.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$186Average$366FlexibilityNo cancel feeOn-time71%
DeltaCheapest$192Average$386FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$292Average$437FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$300Average$520FlexibilityNo cancel feeOn-time69%

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