Idaho

$75+ 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 11/15. Fares are subject to change and may not be available on all flights or dates of travel.
STL — BOI
Dec 2 — Dec 91
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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 November 2, 2025.

This Delta deal was found by Cheapflights users on 10/31. 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.
Fri 12/52:38 pmSTL - GEG
2 stops11h 33mDelta
Mon 12/85:05 amGEG - STL
2 stops12h 05mDelta
Deal found 10/31$236
This Delta deal was found by Cheapflights users on 11/1. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/42:20 pmSTL - JAC
1 stop8h 09mDelta
Sun 12/75:50 pmJAC - STL
1 stop5h 58mDelta
Deal found 11/1$309
This Mytrip deal was found by Cheapflights users on 11/1. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/207:43 pmSTL - GEG
1 stop17h 24mFrontier
Sun 1/412:02 pmGEG - STL
1 stop20h 00mFrontier
Deal found 11/1$326
This Delta deal was found by Cheapflights users on 11/2. 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.
Tue 12/166:00 amSTL - BOI
1 stop7h 54mDelta
Tue 12/303:23 pmBOI - STL
1 stop5h 53mDelta
Deal found 11/2$332
This Orbitz deal was found by Cheapflights users on 11/1. 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/57:00 amSTL - GEG
1 stop19h 24mAlaska Airlines
Mon 12/87:47 pmGEG - STL
1 stop16h 40mAlaska Airlines
Deal found 11/1$334
This American Airlines deal was found by Cheapflights users on 11/1. 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.
Tue 12/95:15 amSTL - GEG
1 stop9h 15mAmerican Airlines
Thu 12/113:05 pmGEG - STL
1 stop6h 51mAmerican Airlines
Deal found 11/1$337
This Southwest deal was found by Cheapflights users on 11/1. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/92:25 pmSTL - GEG
2 stops10h 00mSouthwest
Thu 12/1110:20 amGEG - STL
1 stop7h 45mSouthwest
Deal found 11/1$342
This Delta deal was found by Cheapflights users on 11/1. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/2510:45 amSTL - GEG
2 stops14h 05mDelta
Wed 12/31:10 pmGEG - STL
2 stops9h 51mDelta
Deal found 11/1$356
This Delta deal was found by Cheapflights users on 11/2. 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.
Tue 12/22:20 pmSTL - JAC
1 stop8h 09mDelta
Tue 12/912:55 pmJAC - STL
1 stop5h 15mDelta
Deal found 11/2$384
This Delta deal was found by Cheapflights users on 10/31. 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 12/66:30 amSTL - PIH
1 stop6h 54mDelta
Wed 12/101:04 pmPIH - STL
1 stop5h 06mDelta
Deal found 10/31$417
This Delta deal was found by Cheapflights users on 11/2. 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.
Thu 11/209:04 amSTL - BOI
1 stop6h 05mDelta
Thu 11/271:49 pmBOI - STL
1 stop7h 09mDelta
Deal found 11/2$437
This American Airlines deal was found by Cheapflights users on 11/2. 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.
Sun 11/167:00 amSTL - BOI
1 stop6h 35mAmerican Airlines
Tue 11/186:37 amBOI - STL
1 stop16h 14mAmerican Airlines
Deal found 11/2$498

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 November 2, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$236
(Delta)

One-way from

$75
(Mytrip)

Popular in

December

Cheapest in

April

Average price

$387
Provider with most accurate pricing for Lambert-St Louis-Boise Air Term. Gowen Fld flight deals.
Provider most trusted by Cheapflights users for Lambert-St Louis-Boise Air Term. Gowen Fld flights.
From Lambert-St Louis to Idaho
One-way flight from Lambert-St Louis to Idaho
Highest demand for flights based on searches. 0% potential increase in price ($4 potential increase over avg. RT price).
Cheapest flight prices on average. 1% potential price decrease ($5 potential savings vs. average RT price).
Average for round-trip flights in November 2025

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 November 2, 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

Fri 12/5

2:38 pm-12:11 am

2 stops11h 33m

Spokane

Mon 12/8

5:05 am-7:10 pm

2 stops12h 05m

$236

St. LouisJackson

STL - JAC

STLJAC

Lambert-St Louis

Thu 12/4

2:20 pm-9:29 pm

1 stop8h 09m

Jackson Hole

Sun 12/7

5:50 pm-12:48 am

1 stop5h 58m

$309

St. LouisJackson

STL - JAC

STLJAC

Lambert-St Louis

Thu 1/8

7:00 am-12:00 pm

1 stop6h 00m

Jackson Hole

Tue 1/13

12:58 pm-9:35 pm

1 stop7h 37m

$309

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Sat 12/20

7:43 pm-11:07 am

1 stop17h 24m

Spokane

Sun 1/4

12:02 pm-10:02 am

1 stop20h 00m

$326

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Tue 12/16

6:00 am-12:54 pm

1 stop7h 54m

Boise Air Term. Gowen Fld

Tue 12/30

3:23 pm-10:16 pm

1 stop5h 53m

$332

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Fri 12/5

7:00 am-12:24 am

1 stop19h 24m

Spokane

Mon 12/8

8:47 pm-2:27 pm

1 stop15h 40m

$334

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Tue 12/9

5:15 am-12:30 pm

1 stop9h 15m

Spokane

Thu 12/11

3:05 pm-11:56 pm

1 stop6h 51m

$337

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Tue 12/9

2:25 pm-10:25 pm

2 stops10h 00m

Spokane

Thu 12/11

10:20 am-8:05 pm

1 stop7h 45m

$342

St. LouisSpokane

STL - GEG

STLGEG

Lambert-St Louis

Sat 2/21

7:00 am-12:50 pm

1 stop7h 50m

Spokane

Sun 3/1

12:00 pm-11:56 pm

1 stop9h 56m

$346

St. LouisBoise

STL - BOI

STLBOI

Lambert-St Louis

Tue 3/3

7:00 am-1:45 pm

1 stop7h 45m

Boise Air Term. Gowen Fld

Sun 3/8

6:28 am-11:56 pm

1 stop16h 28m

$349

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/31

Showing 1-10 of 49 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 January is currently the most expensive (average of $300). 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 November 2, 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 November 2, 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.

Crew

8.6

Food

7.0

Boarding

8.1

Comfort

8.0

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines

Crew

8.6

Food

7.0

Boarding

8.1

Comfort

8.0

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines

Crew

8.6

Food

7.0

Boarding

8.1

Comfort

8.0

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines

Crew

8.6

Food

7.0

Boarding

8.1

Comfort

8.0

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines

Crew

8.6

Food

7.0

Boarding

8.1

Comfort

8.0

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines

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 $236, Delta can have you in Idaho from St. Louis in 11h 33m. Airlines will cover a distance of 1488 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 Frontier ($75), Delta ($167), and Alaska Airlines ($224).

  • What are the most popular routes from St. Louis to Idaho?

  • 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 January is currently the most expensive (average of $300). 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.

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 November 2, 2025.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$186Average$366FlexibilityNo cancel feeOn-time71%
DeltaCheapest$192Average$387FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$292Average$437FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$300Average$526FlexibilityNo cancel feeOn-time69%

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