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Idaho

$143+ 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 5/13. Fares are subject to change and may not be available on all flights or dates of travel.
STL — BOI
May 5 — May 121
Mon 5/5
Mon 5/12
1 adult, Economy
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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 April 30, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$227
(CheapOair)

One-way from

$143
(Hawaiian Airlines)

Popular in

December

Cheapest in

October

Average price

$419
Provider with most accurate pricing for Lambert-St Louis-Boise Air Term. Gowen Fld flight deals.
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Provider most trusted by Cheapflights users for Lambert-St Louis-Boise Air Term. Gowen Fld flights.
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From Lambert-St Louis to Idaho
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One-way flight from Lambert-St Louis to Idaho
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Highest demand for flights based on searches. 5% potential increase in price ($25 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($7 potential savings vs. average RT price).
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Average for round-trip flights in April 2025
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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 April 30, 2025.

This CheapOair deal was found by Cheapflights users on 4/28. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/218:15 pmSTL - BOI
1 stop16h 36mFrontier
Sun 5/2512:36 pmBOI - STL
1 stop19h 33mFrontier
Deal found 4/28$227
This Hawaiian Airlines deal was found by Cheapflights users on 4/28. 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 Hawaiian Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/133:35 pmSTL - BOI
1 stop8h 05mHawaiian Airlines
Sat 9/206:35 amBOI - STL
1 stop7h 04mHawaiian Airlines
Deal found 4/28$286
This Delta deal was found by Cheapflights users on 4/28. 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.
Wed 5/286:05 pmSTL - BOI
1 stop7h 17mDelta
Thu 5/2911:59 pmBOI - STL
1 stop8h 01mDelta
Deal found 4/28$287
This United Airlines deal was found by Cheapflights users on 4/28. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/131:41 pmSTL - BOI
1 stop5h 19mUnited Airlines
Sat 5/1711:02 amBOI - STL
2 stops8h 59mUnited Airlines
Deal found 4/28$292
This Delta deal was found by Cheapflights users on 4/29. 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.
Wed 7/168:50 amSTL - GEG
1 stop6h 27mDelta
Wed 7/306:50 amGEG - STL
1 stop7h 52mDelta
Deal found 4/29$299
This United Airlines deal was found by Cheapflights users on 4/28. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/135:20 amSTL - GEG
2 stops11h 21mUnited Airlines
Sat 5/171:40 pmGEG - STL
1 stop8h 18mUnited Airlines
Deal found 4/28$312
This American Airlines deal was found by Cheapflights users on 4/28. 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.
Wed 6/186:00 amSTL - GEG
1 stop9h 11mAmerican Airlines
Sat 7/56:00 amGEG - STL
1 stop6h 19mAmerican Airlines
Deal found 4/28$323
This Delta deal was found by Cheapflights users on 4/28. 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.
Wed 5/282:29 pmSTL - JAC
1 stop7h 19mDelta
Tue 6/37:30 amJAC - STL
1 stop5h 04mDelta
Deal found 4/28$327
This Southwest deal was found by Cheapflights users on 4/28. 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.
Sat 8/165:45 amSTL - BOI
2 stops8h 15mSouthwest
Sat 8/233:35 pmBOI - STL
1 stop6h 10mSouthwest
Deal found 4/28$332
This Hawaiian Airlines deal was found by Cheapflights users on 4/29. 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 Hawaiian Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/116:30 amSTL - GEG
1 stop8h 01mHawaiian Airlines
Wed 5/141:25 pmGEG - STL
1 stop8h 34mHawaiian Airlines
Deal found 4/29$344
This American Airlines deal was found by Cheapflights users on 4/28. 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.
Thu 5/158:05 amSTL - BOI
1 stop6h 15mAmerican Airlines
Wed 5/215:10 pmBOI - STL
1 stop5h 48mAmerican Airlines
Deal found 4/28$344
This Alaska Airlines deal was found by Cheapflights users on 4/28. 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 10/102:55 pmSTL - GEG
1 stop8h 04mAlaska Airlines
Fri 10/171:40 pmGEG - STL
1 stop8h 16mAlaska Airlines
Deal found 4/28$376

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 April 30, 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. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Wed 5/21

8:15 pm-11:51 am

1 stop16h 36m

Boise Air Term. Gowen Fld

Sun 5/25

12:36 pm-9:09 am

1 stop19h 33m

$227

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Sat 9/13

3:35 pm-10:40 pm

1 stop8h 05m

Boise Air Term. Gowen Fld

Sat 9/20

6:35 am-2:39 pm

1 stop7h 04m

$286

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Wed 5/28

6:05 pm-12:22 am

1 stop7h 17m

Boise Air Term. Gowen Fld

Thu 5/29

11:59 pm-9:00 am

1 stop8h 01m

$287

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Tue 5/13

1:41 pm-6:00 pm

1 stop5h 19m

Boise Air Term. Gowen Fld

Sat 5/17

11:02 am-9:01 pm

2 stops8h 59m

$292

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Wed 7/16

8:50 am-1:17 pm

1 stop6h 27m

Spokane

Wed 7/30

6:50 am-4:42 pm

1 stop7h 52m

$299

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Tue 5/13

5:20 am-2:41 pm

2 stops11h 21m

Spokane

Sat 5/17

1:40 pm-11:58 pm

1 stop8h 18m

$312

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Wed 6/18

6:00 am-1:11 pm

1 stop9h 11m

Spokane

Sat 7/5

6:00 am-2:19 pm

1 stop6h 19m

$323

St. LouisJackson

STL - JAC

STLJAC

Lambert-St Louis

Wed 5/28

2:29 pm-8:48 pm

1 stop7h 19m

Jackson Hole

Tue 6/10

6:53 pm-12:43 am

1 stop4h 50m

$327

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Sat 8/16

5:45 am-1:00 pm

2 stops8h 15m

Boise Air Term. Gowen Fld

Sat 8/23

3:35 pm-10:45 pm

1 stop6h 10m

$332

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Sun 5/11

6:30 am-12:31 pm

1 stop8h 01m

Spokane

Wed 5/14

1:25 pm-11:59 pm

1 stop8h 34m

$344

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/29

Showing 1-10 of 38 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, October is the cheapest month in which you can book a flight from St. Louis to Idaho (average of $314). Flying from St. Louis to Idaho in June is currently the most expensive (average of $406). 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 April 30, 2025.

When flying from St. Louis to Idaho, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

Rainfall in Idaho by month

Plan your trip to Idaho by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Idaho ranges from 0.2 - 1.6 inches per month. December is typically the wettest month, when rainfall can reach 1.6 in. August is typically the driest time to visit Idaho when rainfall is around 0.2 in.

Temperature in Idaho by month

Plan your trip to Idaho by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Idaho, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 75.2 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 30.2 F).

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 April 30, 2025.
Read through reviews of airlines operating flights from St. Louis to Idaho, such as Alaska Airlines, Southwest and Delta. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
9,961 reviews

Food

7.1

Boarding

8.2

Overall

8.0

Comfort

7.9

Crew

8.5

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Alaska Airlines
8.0
Very good
9,961 reviews
Alaska Airlines
8.0
Very good
9,961 reviews

Food

7.1

Boarding

8.2

Overall

8.0

Comfort

7.9

Crew

8.5

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Southwest
8.0
Very good
4,295 reviews
Alaska Airlines
8.0
Very good
9,961 reviews

Food

7.1

Boarding

8.2

Overall

8.0

Comfort

7.9

Crew

8.5

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Delta
8.0
Very good
7,936 reviews
Alaska Airlines
8.0
Very good
9,961 reviews

Food

7.1

Boarding

8.2

Overall

8.0

Comfort

7.9

Crew

8.5

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Hawaiian Airlines
7.9
Good
2,402 reviews
Alaska Airlines
8.0
Very good
9,961 reviews

Food

7.1

Boarding

8.2

Overall

8.0

Comfort

7.9

Crew

8.5

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
United Airlines
7.4
Good
8,696 reviews
Alaska Airlines
8.0
Very good
9,961 reviews

Food

7.1

Boarding

8.2

Overall

8.0

Comfort

7.9

Crew

8.5

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

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.

  • 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 Hawaiian Airlines ($143), Delta ($144), and American Airlines ($154).

  • 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, October is the cheapest month in which you can book a flight from St. Louis to Idaho (average of $314). Flying from St. Louis to Idaho in June is currently the most expensive (average of $406). 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 April 30, 2025.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$239Average$564FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$258Average$577FlexibilityNo cancel feeOn-time69%
DeltaCheapest$286Average$494FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$298Average$503FlexibilityNo cancel feeOn-time63%

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