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$168+ 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 2/22. Fares are subject to change and may not be available on all flights or dates of travel.
STL — BOI
Feb 4 — Feb 111
Tue 2/4
Tue 2/11
1 adult, Economy
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Cheap flight deals from St. Louis to Idaho

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Idaho (USID). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated January 30, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$297
(Southwest)

One-way from

$168
(Alaska Airlines)

Popular in

March

Cheapest in

October

Average price

$391
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. 1% potential increase in price ($9 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($13 potential savings vs. average RT price).
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Average for round-trip flights in January 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 January 30, 2025.

This Southwest deal was found by Cheapflights users on 1/29. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/85:45 amSTL - GEG
1 stop8h 15mSouthwest
Mon 4/145:25 amGEG - STL
1 stop5h 45mSouthwest
Deal found 1/29$297
This Delta deal was found by Cheapflights users on 1/29. 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 2/2610:22 amSTL - BOI
2 stops12h 49mDelta
Wed 3/510:35 amBOI - STL
2 stops10h 42mDelta
Deal found 1/29$334
This United Airlines deal was found by Cheapflights users on 1/29. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 2/264:39 pmSTL - BOI
1 stop5h 50mUnited Airlines
Wed 3/511:05 amBOI - STL
1 stop6h 51mUnited Airlines
Deal found 1/29$335
This Alaska Airlines deal was found by Cheapflights users on 1/30. 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 2/217:00 amSTL - BOI
1 stop7h 51mAlaska Airlines
Thu 2/2711:04 amBOI - STL
1 stop11h 55mAlaska Airlines
Deal found 1/30$351
This Delta deal was found by Cheapflights users on 1/28. 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.
Sat 2/223:35 pmSTL - GEG
1 stop6h 32mDelta
Fri 2/287:24 pmGEG - STL
2 stops12h 12mDelta
Deal found 1/28$355
This Southwest deal was found by Cheapflights users on 1/30. 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.
Thu 5/15:20 amSTL - BOI
1 stop5h 45mSouthwest
Sat 5/310:35 amBOI - STL
2 stops9h 35mSouthwest
Deal found 1/30$357
This Alaska Airlines deal was found by Cheapflights users on 1/28. 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.
Sat 2/223:21 pmSTL - GEG
1 stop7h 53mAlaska Airlines
Fri 2/288:43 pmGEG - STL
1 stop15h 42mAlaska Airlines
Deal found 1/28$371
This Mytrip deal was found by Cheapflights users on 1/29. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/69:20 amSTL - BOI
3 stops28h 12mMultiple Airlines
Sat 3/81:31 pmBOI - STL
3 stops25h 14mMultiple Airlines
Deal found 1/29$415
This Delta deal was found by Cheapflights users on 1/30. 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.
Mon 3/246:00 amSTL - JAC
1 stop8h 12mDelta
Fri 3/285:45 pmJAC - STL
1 stop5h 47mDelta
Deal found 1/30$433
This United Airlines deal was found by Cheapflights users on 1/30. 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.
Mon 6/21:30 pmSTL - JAC
1 stop5h 33mUnited Airlines
Fri 6/67:45 amJAC - STL
1 stop6h 59mUnited Airlines
Deal found 1/30$460
This United Airlines deal was found by Cheapflights users on 1/28. 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 3/1110:03 amSTL - GEG
2 stops12h 50mUnited Airlines
Sat 3/155:00 amGEG - STL
2 stops8h 31mUnited Airlines
Deal found 1/28$477
This American Airlines deal was found by Cheapflights users on 1/30. 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 4/244:42 pmSTL - JAC
2 stops20h 31mAmerican Airlines
Mon 4/2812:53 pmJAC - STL
1 stop8h 36mAmerican Airlines
Deal found 1/30$477

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 January 30, 2025.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Tue 4/8

5:45 am-12:00 pm

1 stop8h 15m

Spokane

Mon 4/14

5:25 am-1:10 pm

1 stop5h 45m

$297

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Wed 2/26

6:00 am-1:45 pm

2 stops8h 45m

Boise Air Term. Gowen Fld

Wed 3/5

5:30 am-2:50 pm

1 stop8h 20m

$334

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Wed 2/26

4:39 pm-9:29 pm

1 stop5h 50m

Boise Air Term. Gowen Fld

Wed 3/5

11:05 am-6:56 pm

1 stop6h 51m

$335

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Fri 2/21

7:00 am-1:51 pm

1 stop7h 51m

Boise Air Term. Gowen Fld

Thu 2/27

11:04 am-11:59 pm

1 stop11h 55m

$351

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Sat 2/22

3:35 pm-8:07 pm

1 stop6h 32m

Spokane

Fri 2/28

7:24 pm-9:36 am

2 stops12h 12m

$355

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Thu 5/1

5:20 am-10:05 am

1 stop5h 45m

Boise Air Term. Gowen Fld

Sat 5/3

10:35 am-9:10 pm

2 stops9h 35m

$357

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Sat 2/22

3:21 pm-9:14 pm

1 stop7h 53m

Spokane

Fri 2/28

8:43 pm-2:25 pm

1 stop15h 42m

$371

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Thu 3/6

9:20 am-12:32 pm

3 stops28h 12m

Boise Air Term. Gowen Fld

Sat 3/8

1:31 pm-3:45 pm

3 stops25h 14m

$415

St. LouisJackson

STL - JAC

STLJAC

Lambert-St Louis

Mon 3/24

6:00 am-1:12 pm

1 stop8h 12m

Jackson Hole

Fri 3/28

5:45 pm-12:32 am

1 stop5h 47m

$433

St. LouisJackson

STL - JAC

STLJAC

Lambert-St Louis

Mon 6/2

1:30 pm-6:03 pm

1 stop5h 33m

Jackson Hole

Fri 6/6

7:45 am-3:44 pm

1 stop6h 59m

$460

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/29

Showing 1-10 of 28 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 $436). 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 January 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 January 30, 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
4,585 reviews

Crew

8.7

Food

7.1

Entertainment

7.7

Boarding

8.2

Comfort

8.1

Overall

8.1

Reviews

1 / 20

6.0
Good

Lauren,Dec 2024

MCI - DCA

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

Southwest
8.1
Very good
4,585 reviews
Southwest
8.1
Very good
4,585 reviews

Crew

8.7

Food

7.1

Entertainment

7.7

Boarding

8.2

Comfort

8.1

Overall

8.1

Reviews

1 / 20

6.0
Good

Lauren,Dec 2024

MCI - DCA

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

Alaska Airlines
8.0
Very good
9,688 reviews
Southwest
8.1
Very good
4,585 reviews

Crew

8.7

Food

7.1

Entertainment

7.7

Boarding

8.2

Comfort

8.1

Overall

8.1

Reviews

1 / 20

6.0
Good

Lauren,Dec 2024

MCI - DCA

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

Delta
8.0
Very good
8,454 reviews
Southwest
8.1
Very good
4,585 reviews

Crew

8.7

Food

7.1

Entertainment

7.7

Boarding

8.2

Comfort

8.1

Overall

8.1

Reviews

1 / 20

6.0
Good

Lauren,Dec 2024

MCI - DCA

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

United Airlines
7.4
Good
8,913 reviews
Southwest
8.1
Very good
4,585 reviews

Crew

8.7

Food

7.1

Entertainment

7.7

Boarding

8.2

Comfort

8.1

Overall

8.1

Reviews

1 / 20

6.0
Good

Lauren,Dec 2024

MCI - DCA

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

American Airlines
7.2
Good
10,000 reviews
Southwest
8.1
Very good
4,585 reviews

Crew

8.7

Food

7.1

Entertainment

7.7

Boarding

8.2

Comfort

8.1

Overall

8.1

Reviews

1 / 20

6.0
Good

Lauren,Dec 2024

MCI - DCA

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

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 Alaska Airlines ($168), Delta ($168), and Southwest ($229).

  • 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 $436). 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 January 30, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$258Average$596FlexibilityNo cancel feeOn-time69%
DeltaCheapest$258Average$527FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$280Average$592FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$366Average$503FlexibilityNo cancel feeOn-time63%
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