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Idaho

$80+ 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 1/21. Fares are subject to change and may not be available on all flights or dates of travel.
STL — BOI
ene. 11 — ene. 181
dom. 1/11
dom. 1/18
1 adult, Economy
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Cheap 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 diciembre 12, 2025.

This Kiwi.com deal was found by Cheapflights users on 12/9. 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.
sáb. 12/207:43 pmSTL - BOI
1 stop17h 00mFrontier
dom. 1/412:38 pmBOI - STL
1 stop20h 24mFrontier
Deal found 12/9$443
This Delta deal was found by Cheapflights users on 12/10. 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.
dom. 12/146:15 amSTL - JAC
1 stop6h 45mDelta
dom. 12/217:00 amJAC - STL
1 stop5h 23mDelta
Deal found 12/10$454
This Delta deal was found by Cheapflights users on 12/11. 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.
sáb. 12/135:00 pmSTL - JAC
1 stop5h 29mDelta
mié. 12/175:50 pmJAC - STL
1 stop6h 11mDelta
Deal found 12/11$509
This Delta deal was found by Cheapflights users on 12/10. 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.
jue. 12/257:20 amSTL - LWS
1 stop6h 16mDelta
lun. 12/2912:16 pmLWS - STL
1 stop7h 18mDelta
Deal found 12/10$558
This Kiwi.com deal was found by Cheapflights users on 12/11. 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.
vie. 12/2610:10 pmSTL - GEG
2 stops14h 57mFrontier
mar. 12/3012:02 pmGEG - STL
1 stop20h 00mFrontier
Deal found 12/11$592
This Kiwi.com deal was found by Cheapflights users on 12/11. 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.
lun. 12/2910:10 pmSTL - BOI
2 stops39h 42mMultiple Airlines
dom. 1/412:38 pmBOI - STL
1 stop20h 24mMultiple Airlines
Deal found 12/11$665
This Kiwi.com deal was found by Cheapflights users on 12/11. 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.
vie. 12/2610:10 pmSTL - GEG
1 stop14h 19mMultiple Airlines
mar. 12/3012:02 pmGEG - STL
1 stop20h 00mMultiple Airlines
Deal found 12/11$670
This Southwest deal was found by Cheapflights users on 12/11. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 12/295:00 amSTL - BOI
1 stop7h 05mSouthwest
dom. 1/45:00 amBOI - STL
1 stop6h 20mSouthwest
Deal found 12/11$674
This Kiwi.com deal was found by Cheapflights users on 12/11. 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.
dom. 12/141:16 pmSTL - GEG
1 stop9h 07mMultiple Airlines
jue. 12/187:51 pmGEG - STL
2 stops12h 11mMultiple Airlines
Deal found 12/11$691
This Delta deal was found by Cheapflights users on 12/11. 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.
vie. 12/266:05 amSTL - BOI
2 stops9h 44mDelta
mar. 12/303:23 pmBOI - STL
1 stop5h 53mDelta
Deal found 12/11$731
This Southwest deal was found by Cheapflights users on 12/9. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 12/204:20 pmSTL - BOI
2 stops9h 40mSouthwest
dom. 1/41:05 pmBOI - STL
2 stops9h 00mSouthwest
Deal found 12/9$737
This American Airlines deal was found by Cheapflights users on 12/11. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
vie. 12/262:43 pmSTL - IDA
1 stop8h 38mAmerican Airlines
mar. 12/301:16 pmIDA - STL
1 stop8h 40mAmerican Airlines
Deal found 12/11$746

Find 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 diciembre 12, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$186
(Kiwi.com)

One-way from

$148
(Delta)

Popular in

February

Cheapest in

November

Average price

$466
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. 7% potential increase in price ($34 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($10 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in December 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 diciembre 12, 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

mar. 1/20

3:31 pm-11:59 pm

2 stops10h 28m

Spokane

sáb. 1/24

6:20 am-9:38 pm

2 stops13h 18m

$256

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

vie. 1/23

3:31 pm-11:59 pm

2 stops10h 28m

Spokane

sáb. 1/24

11:25 am-9:38 pm

2 stops8h 13m

$256

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

mié. 1/21

3:31 pm-11:59 pm

2 stops10h 28m

Spokane

sáb. 1/24

7:20 am-9:38 pm

2 stops12h 18m

$256

St. LouisJackson

STL - JAC

STLJAC

Lambert-St Louis

vie. 1/9

7:10 am-1:30 pm

1 stop7h 20m

Jackson Hole

vie. 1/16

12:58 pm-9:35 pm

1 stop7h 37m

$257

St. LouisJackson

STL - JAC

STLJAC

Lambert-St Louis

jue. 1/8

6:00 am-1:30 pm

1 stop8h 30m

Jackson Hole

mar. 1/13

12:58 pm-9:35 pm

1 stop7h 37m

$257

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

dom. 1/18

5:00 pm-10:51 pm

1 stop7h 51m

Spokane

vie. 1/23

7:25 pm-1:48 pm

2 stops16h 23m

$275

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

dom. 1/18

5:00 pm-10:51 pm

1 stop7h 51m

Spokane

sáb. 1/24

5:20 am-9:38 pm

2 stops14h 18m

$275

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

mar. 1/20

3:31 pm-7:54 pm

1 stop6h 23m

Spokane

vie. 1/23

7:25 pm-1:48 pm

2 stops16h 23m

$275

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

dom. 1/18

5:00 pm-10:51 pm

1 stop7h 51m

Spokane

mar. 1/20

2:00 pm-11:25 pm

1 stop7h 25m

$295

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

dom. 1/18

5:00 pm-10:51 pm

1 stop7h 51m

Spokane

jue. 1/22

11:25 am-11:25 pm

2 stops10h 00m

$295

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/11

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 December is currently the most expensive (average of $331). 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 diciembre 12, 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 diciembre 12, 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
7.9
Good
4,253 reviews

Food

7.0

Comfort

8.0

Crew

8.6

Entertainment

7.5

Overall

7.9

Boarding

8.1

Reviews

1 / 20
2.0
Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am
Southwest
7.9
Good
4,253 reviews
Southwest
7.9
Good
4,253 reviews

Food

7.0

Comfort

8.0

Crew

8.6

Entertainment

7.5

Overall

7.9

Boarding

8.1

Reviews

1 / 20
2.0
Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am
Delta
7.9
Good
8,008 reviews
Southwest
7.9
Good
4,253 reviews

Food

7.0

Comfort

8.0

Crew

8.6

Entertainment

7.5

Overall

7.9

Boarding

8.1

Reviews

1 / 20
2.0
Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am
United Airlines
7.4
Good
9,095 reviews
Southwest
7.9
Good
4,253 reviews

Food

7.0

Comfort

8.0

Crew

8.6

Entertainment

7.5

Overall

7.9

Boarding

8.1

Reviews

1 / 20
2.0
Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am
American Airlines
7.2
Good
11,050 reviews
Southwest
7.9
Good
4,253 reviews

Food

7.0

Comfort

8.0

Crew

8.6

Entertainment

7.5

Overall

7.9

Boarding

8.1

Reviews

1 / 20
2.0
Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am

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 $376, Delta can have you in Idaho from St. Louis in 8h 26m. 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 Southwest ($82), Delta ($139), and United Airlines ($156).

  • 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 - Boise Air Term. Gowen Fld or Lambert-St Louis - Spokane.

  • 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 December is currently the most expensive (average of $331). 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 diciembre 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$186Average$366FlexibilityNo cancel feeOn-time71%
DeltaCheapest$192Average$387FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$292Average$410FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$300Average$527FlexibilityNo cancel feeOn-time69%

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