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$148+ 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 1/20. Fares are subject to change and may not be available on all flights or dates of travel.
STL — BOI
Dec 27 — Jan 31
Fri 12/27
Fri 1/3
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 December 22, 2024.

Round-trip from

$258
(Delta)

One-way from

$152
(Delta)
From Lambert-St Louis to Idaho
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One-way flight from Lambert-St Louis to Idaho
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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 December 22, 2024.

This American Airlines deal was found by Cheapflights users on 12/20. 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 12/261:45 pmSTL - BOI
1 stop9h 07mAmerican Airlines
Sat 1/42:05 pmBOI - STL
1 stop9h 01mAmerican Airlines
Deal found 12/20$781
This United deal was found by Cheapflights users on 12/21. 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 is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/268:50 amSTL - BOI
1 stop8h 42mUnited Airlines
Sat 1/47:00 amBOI - STL
1 stop8h 25mUnited Airlines
Deal found 12/21$799
This United Airlines deal was found by Cheapflights users on 12/21. 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.
Sun 12/224:43 pmSTL - JAC
1 stop5h 19mUnited Airlines
Sun 12/297:00 amJAC - STL
2 stops15h 59mUnited Airlines
Deal found 12/21$834
This Southwest deal was found by Cheapflights users on 12/20. 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.
Fri 12/2010:50 pmSTL - BOI
1 stop12h 55mSouthwest
Mon 12/235:30 amBOI - STL
1 stop6h 35mSouthwest
Deal found 12/20$910
This Alaska Airlines deal was found by Cheapflights users on 12/21. 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.
Sun 12/222:23 pmSTL - JAC
1 stop28h 56mAlaska Airlines
Sun 12/296:59 pmJAC - STL
1 stop17h 28mAlaska Airlines
Deal found 12/21$942
This Alaska Airlines deal was found by Cheapflights users on 12/21. 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.
Thu 12/267:00 amSTL - BOI
1 stop8h 54mAlaska Airlines
Sat 1/47:00 amBOI - STL
2 stops15h 59mAlaska Airlines
Deal found 12/21$968
This Alaska Airlines deal was found by Cheapflights users on 12/21. 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.
Mon 12/302:23 pmSTL - IDA
1 stop25h 33mAlaska Airlines
Sun 1/53:34 pmIDA - STL
1 stop21h 19mAlaska Airlines
Deal found 12/21$998
This American Airlines deal was found by Cheapflights users on 12/21. 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.
Mon 12/309:30 amSTL - IDA
2 stops13h 51mAmerican Airlines
Sun 1/51:44 pmIDA - STL
1 stop7h 37mAmerican Airlines
Deal found 12/21$1,044
This Delta deal was found by Cheapflights users on 12/21. 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 12/226:00 amSTL - JAC
1 stop8h 09mDelta
Thu 1/21:15 pmJAC - STL
1 stop7h 19mDelta
Deal found 12/21$1,065

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 December 22, 2024.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

St. LouisLewiston

STL - LWS

STLLWS

Lambert-St Louis

Sun 1/19

7:40 am-11:58 am

1 stop6h 18m

Lewiston Nez Perce Rgnl

Sat 1/25

12:38 pm-9:33 pm

1 stop6h 55m

$258

St. LouisLewiston

STL - LWS

STLLWS

Lambert-St Louis

Sun 1/19

1:02 pm-10:36 pm

2 stops11h 34m

Lewiston Nez Perce Rgnl

Sat 1/25

5:36 am-5:36 pm

2 stops10h 00m

$268

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Sat 1/18

6:44 am-1:49 pm

1 stop9h 05m

Spokane

Sat 1/25

3:21 pm-11:57 pm

1 stop6h 36m

$296

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Sat 2/15

7:15 am-1:16 pm

1 stop7h 01m

Boise Air Term. Gowen Fld

Tue 2/18

1:56 pm-11:39 pm

1 stop8h 43m

$310

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Sat 1/18

5:00 pm-11:02 pm

1 stop7h 02m

Boise Air Term. Gowen Fld

Sat 1/25

7:55 am-11:14 pm

2 stops14h 19m

$317

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Wed 1/22

5:00 pm-11:57 pm

1 stop8h 57m

Spokane

Tue 1/28

1:25 pm-11:14 pm

2 stops7h 49m

$319

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Mon 4/7

3:11 pm-9:56 pm

1 stop8h 45m

Spokane

Fri 4/11

5:48 pm-2:15 pm

1 stop18h 27m

$324

St. LouisIdaho Falls

STL - IDA

STLIDA

Lambert-St Louis

Thu 1/23

2:13 pm-6:17 pm

1 stop5h 04m

Idaho Falls Fanning Field

Sun 1/26

6:57 pm-12:38 am

1 stop4h 41m

$325

St. LouisJackson

STL - JAC

STLJAC

Lambert-St Louis

Tue 1/28

5:03 am-12:07 pm

1 stop8h 04m

Jackson Hole

Sun 2/2

1:33 pm-11:03 pm

1 stop8h 30m

$366

St. LouisIdaho Falls

STL - IDA

STLIDA

Lambert-St Louis

Wed 1/15

2:27 pm-10:17 pm

1 stop8h 50m

Idaho Falls Fanning Field

Sun 1/19

12:55 pm-7:30 pm

1 stop5h 35m

$381

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/21

Showing 1-10 of 29 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 December 22, 2024.

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 December 22, 2024.
Read through reviews of airlines operating flights from St. Louis to Idaho, such as Southwest, United Airlines and Alaska Airlines. 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
4,804 reviews

Food

7.2

Boarding

8.2

Entertainment

7.7

Comfort

8.1

Overall

8.1

Crew

8.7

Reviews

1 / 10

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
4,804 reviews
Southwest
8.1
Very good
4,804 reviews

Food

7.2

Boarding

8.2

Entertainment

7.7

Comfort

8.1

Overall

8.1

Crew

8.7

Reviews

1 / 10

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
9,537 reviews
Southwest
8.1
Very good
4,804 reviews

Food

7.2

Boarding

8.2

Entertainment

7.7

Comfort

8.1

Overall

8.1

Crew

8.7

Reviews

1 / 10

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
8,597 reviews
Southwest
8.1
Very good
4,804 reviews

Food

7.2

Boarding

8.2

Entertainment

7.7

Comfort

8.1

Overall

8.1

Crew

8.7

Reviews

1 / 10

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
9,035 reviews
Southwest
8.1
Very good
4,804 reviews

Food

7.2

Boarding

8.2

Entertainment

7.7

Comfort

8.1

Overall

8.1

Crew

8.7

Reviews

1 / 10

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
4,804 reviews

Food

7.2

Boarding

8.2

Entertainment

7.7

Comfort

8.1

Overall

8.1

Crew

8.7

Reviews

1 / 10

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 Delta ($152), American Airlines ($163), and Alaska Airlines ($214).

  • 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, 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 December 22, 2024.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$258Average$571FlexibilityNo cancel feeOn-time69%
DeltaCheapest$296Average$529FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$334Average$649FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$367Average$533FlexibilityNo cancel feeOn-time63%
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