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$129+ 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 5/1. Fares are subject to change and may not be available on all flights or dates of travel.
STL — BOI
Mar 8 — Mar 151
Sat 3/8
Sat 3/15
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 March 3, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$180
(CheapOair)

One-way from

$129
(Southwest)

Popular in

March

Cheapest in

October

Average price

$534
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 ($8 potential savings vs. average RT price).
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Average for round-trip flights in March 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 March 3, 2025.

This CheapOair deal was found by Cheapflights users on 3/3. 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 5/146:53 pmSTL - BOI
1 stop19h 44mFrontier
Sun 5/182:27 pmBOI - STL
1 stop17h 42mFrontier
Deal found 3/3$180
This Alaska Airlines deal was found by Cheapflights users on 3/2. 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.
Tue 4/16:44 amSTL - BOI
1 stop6h 48mAlaska Airlines
Tue 4/88:00 amBOI - STL
1 stop14h 59mAlaska Airlines
Deal found 3/2$226
This American Airlines deal was found by Cheapflights users on 3/2. 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.
Sat 4/195:26 amSTL - BOI
1 stop8h 07mAmerican Airlines
Sat 4/267:05 amBOI - STL
1 stop8h 31mAmerican Airlines
Deal found 3/2$227
This Southwest deal was found by Cheapflights users on 3/2. 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.
Tue 4/12:10 pmSTL - BOI
2 stops9h 35mSouthwest
Tue 4/86:35 amBOI - STL
1 stop6h 00mSouthwest
Deal found 3/2$232
This Delta deal was found by Cheapflights users on 3/2. 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.
Sat 4/195:33 pmSTL - BOI
1 stop7h 30mDelta
Sat 4/269:00 amBOI - STL
2 stops11h 03mDelta
Deal found 3/2$300
This Mytrip deal was found by Cheapflights users on 3/2. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/87:37 pmSTL - BOI
2 stops26h 07mMultiple Airlines
Mon 5/129:49 pmBOI - STL
3 stops36h 56mMultiple Airlines
Deal found 3/2$304
This United Airlines deal was found by Cheapflights users on 3/2. 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.
Wed 4/24:45 pmSTL - GEG
1 stop6h 05mUnited Airlines
Tue 4/85:14 amGEG - STL
1 stop5h 33mUnited Airlines
Deal found 3/2$307
This Delta deal was found by Cheapflights users on 3/2. 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.
Sun 5/44:16 pmSTL - GEG
1 stop7h 13mDelta
Wed 5/77:21 pmGEG - STL
2 stops13h 16mDelta
Deal found 3/2$316
This Hawaiian Airlines deal was found by Cheapflights users on 3/2. 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.
Wed 3/266:44 amSTL - IDA
1 stop9h 50mHawaiian Airlines
Wed 4/24:11 pmIDA - STL
1 stop6h 48mHawaiian Airlines
Deal found 3/2$324
This American Airlines deal was found by Cheapflights users on 3/1. 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.
Fri 5/26:20 pmSTL - GEG
1 stop6h 39mAmerican Airlines
Mon 5/53:21 pmGEG - STL
1 stop6h 34mAmerican Airlines
Deal found 3/1$327
This Delta deal was found by Cheapflights users on 3/2. 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 3/267:40 amSTL - IDA
1 stop5h 38mDelta
Wed 4/26:55 pmIDA - STL
2 stops13h 41mDelta
Deal found 3/2$330
This Alaska Airlines deal was found by Cheapflights users on 3/2. 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.
Tue 4/13:11 pmSTL - IDA
1 stop8h 24mAlaska Airlines
Mon 4/74:11 pmIDA - STL
1 stop6h 48mAlaska Airlines
Deal found 3/2$334

Find flights from St. Louis to Idaho within your budget

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 March 3, 2025.

Fly from

St. Louis

Fly to

Idaho

Route

Depart

Return

Price

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Wed 5/14

6:53 pm-1:37 pm

1 stop19h 44m

Boise Air Term. Gowen Fld

Sun 5/18

2:27 pm-9:09 am

1 stop17h 42m

$180

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Tue 4/1

6:44 am-12:32 pm

1 stop6h 48m

Boise Air Term. Gowen Fld

Tue 4/8

8:00 am-11:59 pm

1 stop14h 59m

$226

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Sat 4/19

5:26 am-12:33 pm

1 stop8h 07m

Boise Air Term. Gowen Fld

Sat 4/26

7:05 am-4:36 pm

1 stop8h 31m

$227

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Tue 4/1

2:10 pm-10:45 pm

2 stops9h 35m

Boise Air Term. Gowen Fld

Tue 4/8

6:35 am-1:35 pm

1 stop6h 00m

$232

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Sat 4/19

5:33 pm-12:03 am

1 stop7h 30m

Boise Air Term. Gowen Fld

Sat 4/26

9:00 am-9:03 pm

2 stops11h 03m

$300

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Thu 5/8

7:37 pm-8:44 pm

2 stops26h 07m

Boise Air Term. Gowen Fld

Mon 5/12

9:49 pm-11:45 am

3 stops36h 56m

$304

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Wed 4/2

4:45 pm-8:50 pm

1 stop6h 05m

Spokane

Tue 4/8

5:14 am-12:47 pm

1 stop5h 33m

$307

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Sun 5/4

4:16 pm-9:29 pm

1 stop7h 13m

Spokane

Wed 5/7

7:21 pm-10:37 am

2 stops13h 16m

$316

St. LouisIdaho Falls

STL - IDA

STLIDA

Lambert-St Louis

Wed 3/26

6:44 am-3:34 pm

1 stop9h 50m

Idaho Falls Fanning Field

Wed 4/2

4:11 pm-11:59 pm

1 stop6h 48m

$324

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Fri 5/2

6:20 pm-10:59 pm

1 stop6h 39m

Spokane

Mon 5/5

3:21 pm-11:55 pm

1 stop6h 34m

$327

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/3

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.

Travel insights for flights from St. Louis to Idaho

Get recent, data-driven insights about flights from St. Louis to Idaho including ideal travel times, pricing trends, and more.

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 $432). 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 March 3, 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 March 3, 2025.
Read through reviews of airlines operating flights from St. Louis to Idaho, such as Southwest, Alaska Airlines and Delta. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.1
Very good
4,333 reviews

Crew

8.7

Comfort

8.1

Food

7.1

Entertainment

7.6

Overall

8.1

Boarding

8.2

Reviews

1 / 20

8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

Southwest
8.1
Very good
4,333 reviews
Southwest
8.1
Very good
4,333 reviews

Crew

8.7

Comfort

8.1

Food

7.1

Entertainment

7.6

Overall

8.1

Boarding

8.2

Reviews

1 / 20

8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

Alaska Airlines
8.0
Very good
9,713 reviews
Southwest
8.1
Very good
4,333 reviews

Crew

8.7

Comfort

8.1

Food

7.1

Entertainment

7.6

Overall

8.1

Boarding

8.2

Reviews

1 / 20

8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

Delta
8.0
Very good
8,070 reviews
Southwest
8.1
Very good
4,333 reviews

Crew

8.7

Comfort

8.1

Food

7.1

Entertainment

7.6

Overall

8.1

Boarding

8.2

Reviews

1 / 20

8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

Hawaiian Airlines
7.9
Good
2,320 reviews
Southwest
8.1
Very good
4,333 reviews

Crew

8.7

Comfort

8.1

Food

7.1

Entertainment

7.6

Overall

8.1

Boarding

8.2

Reviews

1 / 20

8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

United Airlines
7.4
Good
8,679 reviews
Southwest
8.1
Very good
4,333 reviews

Crew

8.7

Comfort

8.1

Food

7.1

Entertainment

7.6

Overall

8.1

Boarding

8.2

Reviews

1 / 20

8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

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 Southwest ($129), Alaska Airlines ($153), and Delta ($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 $432). 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 March 3, 2025.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$239Average$592FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$258Average$584FlexibilityNo cancel feeOn-time69%
DeltaCheapest$296Average$550FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$366Average$526FlexibilityNo cancel feeOn-time63%
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