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$127+ Cheap flights from Boise to St. Louis (BOI - STL)

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 8/21. Fares are subject to change and may not be available on all flights or dates of travel.
BOI — STL
Aug 3 — Aug 101
Sun 8/3
Sun 8/10
1 adult, Economy
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Cheapflights Tip: The best prices from Boise Air Term. Gowen Fld to Lambert-St Louis are usually found in April or August, booked 36 days in advance, depart on a Tuesday or Friday and return on a Wednesday

Cheap flight deals from Boise to St. Louis

Discover tips and strategies to find the most affordable flight options for your journey from Boise (BOI) to St. Louis (STL). 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 July 29, 2025.

Round-trip from

$274
(United Airlines)

One-way from

$127
(FlightHub)

Popular in

January

Cheapest in

April

Average price

$421
From Boise Air Term. Gowen Fld to Lambert-St Louis
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One-way flight from Boise Air Term. Gowen Fld to Lambert-St Louis
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Highest demand for flights based on searches. 17% potential increase in price ($93 potential increase over avg. RT price).
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Cheapest flight prices on average. 9% potential price decrease ($37 potential savings vs. average RT price).
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Average for round-trip flights in July 2025
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Find flight deals from Boise to St. Louis

Cheapest flights from Boise to St. Louis
Explore the most affordable flight options available from Boise to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 29, 2025.

This United Airlines deal was found by Cheapflights users on 7/28. 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.
Mon 8/185:42 pmBOI - STL
1 stop5h 17mUnited Airlines
Tue 8/196:35 amSTL - BOI
1 stop5h 56mUnited Airlines
Deal found 7/28$274
This Hawaiian Airlines deal was found by Cheapflights users on 7/28. 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.
Fri 9/196:35 amBOI - STL
1 stop7h 04mHawaiian Airlines
Mon 9/223:35 pmSTL - BOI
1 stop9h 33mHawaiian Airlines
Deal found 7/28$278
This American Airlines deal was found by Cheapflights users on 7/28. 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.
Mon 8/255:15 pmBOI - STL
1 stop6h 01mAmerican Airlines
Mon 9/16:00 amSTL - BOI
1 stop7h 29mAmerican Airlines
Deal found 7/28$279
This Delta deal was found by Cheapflights users on 7/28. 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.
Fri 9/195:43 pmBOI - STL
1 stop5h 55mDelta
Mon 9/222:31 pmSTL - BOI
2 stops10h 21mDelta
Deal found 7/28$322
This Southwest deal was found by Cheapflights users on 7/28. 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.
Mon 8/185:45 amBOI - STL
2 stops7h 45mSouthwest
Tue 8/192:25 pmSTL - BOI
2 stops9h 00mSouthwest
Deal found 7/28$329
This Alaska Airlines deal was found by Cheapflights users on 7/28. 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 10/37:17 pmBOI - STL
1 stop18h 44mAlaska Airlines
Sun 10/53:57 pmSTL - BOI
1 stop8h 08mAlaska Airlines
Deal found 7/28$353
This Mytrip deal was found by Cheapflights users on 7/28. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/47:48 pmBOI - STL
3 stops19h 57mMultiple Airlines
Thu 8/710:47 amSTL - BOI
3 stops33h 05mMultiple Airlines
Deal found 7/28$650
This Mytrip deal was found by Cheapflights users on 7/28. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/47:48 pmBOI - STL
2 stops19h 43mSpirit Airlines
Thu 8/710:47 amSTL - BOI
3 stops33h 05mSpirit Airlines
Deal found 7/28$745

Cheapflights Fare Finder

 
Customize your flight search to find flights from Boise to St. Louis 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 July 29, 2025.
Use the filters below to find and compare flights from Boise to St. Louis that are best for you.

Fly from

Boise

Fly to

St. Louis

Route

Depart

Return

Price

BoiseSt. Louis

BOI - STL

BOISTL

Boise Air Term. Gowen Fld

Mon 8/18

5:42 pm-11:59 pm

1 stop5h 17m

Lambert-St Louis

Tue 8/19

6:35 am-11:31 am

1 stop5h 56m

$274

BoiseSt. Louis

BOI - STL

BOISTL

Boise Air Term. Gowen Fld

Fri 9/19

6:35 am-2:39 pm

1 stop7h 04m

Lambert-St Louis

Mon 9/22

3:35 pm-12:08 am

1 stop9h 33m

$278

BoiseSt. Louis

BOI - STL

BOISTL

Boise Air Term. Gowen Fld

Mon 8/25

5:15 pm-12:16 am

1 stop6h 01m

Lambert-St Louis

Mon 9/1

6:00 am-12:29 pm

1 stop7h 29m

$279

BoiseSt. Louis

BOI - STL

BOISTL

Boise Air Term. Gowen Fld

Fri 9/19

5:43 pm-12:38 am

1 stop5h 55m

Lambert-St Louis

Mon 9/22

2:31 pm-11:52 pm

2 stops10h 21m

$322

BoiseSt. Louis

BOI - STL

BOISTL

Boise Air Term. Gowen Fld

Mon 8/18

5:45 am-2:30 pm

2 stops7h 45m

Lambert-St Louis

Tue 8/19

2:25 pm-10:25 pm

2 stops9h 00m

$329

BoiseSt. Louis

BOI - STL

BOISTL

Boise Air Term. Gowen Fld

Fri 10/3

7:17 pm-3:01 pm

1 stop18h 44m

Lambert-St Louis

Sun 10/5

3:57 pm-11:05 pm

1 stop8h 08m

$353

BoiseSt. Louis

BOI - STL

BOISTL

Boise Air Term. Gowen Fld

Thu 8/21

12:33 pm-9:11 am

1 stop19h 38m

$127

BoiseSt. Louis

BOI - STL

BOISTL

Boise Air Term. Gowen Fld

Mon 8/18

6:00 pm-12:38 am

1 stop5h 38m

$140

BoiseSt. Louis

BOI - STL

BOISTL

Boise Air Term. Gowen Fld

Wed 8/20

7:25 am-10:15 pm

2 stops13h 50m

$150

BoiseSt. Louis

BOI - STL

BOISTL

Boise Air Term. Gowen Fld

Thu 9/11

2:16 pm-11:21 am

2 stops20h 05m

$171

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/28

Showing 1-10 of 12 results
1
2

Best time to book a flight from Boise to St. Louis

Have a flexible travel schedule? Discover the best time to fly to St. Louis from Boise 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 Boise to St. Louis

How far ahead should I book a flight from Boise to St. Louis?

Use this chart to determine the optimal time to book a round-trip flight from Boise to St. Louis. Price data was last updated on July 25, 2025.

To ensure you get the cheapest price possible for a flight from Boise to St. Louis, you should look to book at least 36 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.

What is the cheapest month to book a flight from Boise to St. Louis?

Currently, August is the cheapest month in which you can book a flight from Boise to St. Louis (average of $311). Flying from Boise to St. Louis in March is currently the most expensive (average of $356). 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 BOI to STL?

Find hourly flight availability from Boise to St. Louis. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated July 29, 2025.

When flying from Boise to St. Louis, the time of day you fly usually plays a role in the price. Save by searching for a flight in the afternoon, which can drop the price by up to 18% versus a flight in the morning.

What’s the top layover airport for flights from Boise to St. Louis?

Share of 1-stop round-trip flights from Boise to St. Louis chosen by Cheapflights users in the past 12 months, using the same layover each way.

Denver (DEN) – chosen by Cheapflights users on 67% of 1-stop itineraries from Boise to St. Louis on Cheapflights.

What’s the cheapest layover airport for flights from Boise to St. Louis?

Average round-trip fare for 1-stop flights from Boise to St. Louis, chosen by Cheapflights users in the past 12 months, with the same layover each way.

Denver (DEN) is the most affordable 1-stop option, with an average round-trip price of $506.

What’s the fastest layover option from Boise to St. Louis?

Shortest average travel time for 1-stop one-way flights from Boise to St. Louis, based on itineraries clicked by Cheapflights users over the past 12 months, grouped by layover airport.

Flights via Denver (DEN) have the shortest average one-way travel time for 1-stop routes: 3h 05m.

Which airport typically offers the quickest layover for flights from Boise to St. Louis?

Average layover duration for 1-stop one-way flights from Boise to St. Louis, chosen by Cheapflights users in the last 12 months, grouped by stopover airport.

Flights via Denver (DEN) offer the fastest connection on this route, with an average layover time of 1h 45m.

Reviews of airlines servicing St. Louis

Get insights into the airlines that provide service to St. Louis. 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 St. Louis. Reviews last updated July 29, 2025.
Peruse reviews from past customers who have flown with Alaska Airlines, Southwest, and Delta from Boise to St. Louis to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
10,000 reviews

Food

7.1

Crew

8.5

Boarding

8.1

Overall

8.0

Entertainment

7.1

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Jonathan,Jul 2025

SEA - BOS

Fantastic Check-in with easy baggage drop. While it took a while to find out which was the gate, the boarding was a dream, the stewards were simply incredible and the flight fantastic.
Alaska Airlines
8.0
Very good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Food

7.1

Crew

8.5

Boarding

8.1

Overall

8.0

Entertainment

7.1

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Jonathan,Jul 2025

SEA - BOS

Fantastic Check-in with easy baggage drop. While it took a while to find out which was the gate, the boarding was a dream, the stewards were simply incredible and the flight fantastic.
Southwest
8.0
Very good
4,238 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Food

7.1

Crew

8.5

Boarding

8.1

Overall

8.0

Entertainment

7.1

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Jonathan,Jul 2025

SEA - BOS

Fantastic Check-in with easy baggage drop. While it took a while to find out which was the gate, the boarding was a dream, the stewards were simply incredible and the flight fantastic.
Delta
8.0
Very good
7,977 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Food

7.1

Crew

8.5

Boarding

8.1

Overall

8.0

Entertainment

7.1

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Jonathan,Jul 2025

SEA - BOS

Fantastic Check-in with easy baggage drop. While it took a while to find out which was the gate, the boarding was a dream, the stewards were simply incredible and the flight fantastic.
Hawaiian Airlines
7.8
Good
2,605 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Food

7.1

Crew

8.5

Boarding

8.1

Overall

8.0

Entertainment

7.1

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Jonathan,Jul 2025

SEA - BOS

Fantastic Check-in with easy baggage drop. While it took a while to find out which was the gate, the boarding was a dream, the stewards were simply incredible and the flight fantastic.
United Airlines
7.4
Good
8,899 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Food

7.1

Crew

8.5

Boarding

8.1

Overall

8.0

Entertainment

7.1

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Jonathan,Jul 2025

SEA - BOS

Fantastic Check-in with easy baggage drop. While it took a while to find out which was the gate, the boarding was a dream, the stewards were simply incredible and the flight fantastic.

Related info for your journey

Find useful and relevant information for your journey from Boise to St. Louis. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What are the cheapest airlines flying from Boise to St. Louis round-trip?

    Currently priced at $274, United Airlines will fly you from Boise to St. Louis and back. In addition to United Airlines, many other airlines offer competitively priced options for your trip. Search Cheapflights for deals from Hawaiian Airlines and American Airlines - these airlines can fly you to your destination from $278 and $279, respectively. You may be able to fly from Boise to St. Louis for 36% less than the average price by searching for these airlines.

  • What are the cheapest airlines to fly from Boise to St. Louis one-way?

    The cheapest airlines for a one-way flight from Boise to St. Louis are Frontier ($127), Delta ($140), and Southwest ($150).

  • Can I find deals for flights from Boise to St. Louis that include hotel bookings?

    Yes. In addition to deals on Boise to St. Louis flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Boise to St. Louis?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Boise to St. Louis.

  • Can I find deals for business class flights from Boise to St. Louis?

    Yes. Cheapflights offers flight deals from Boise to St. Louis 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 Boise to St. Louis?

    Currently, August is the cheapest month in which you can book a flight from Boise to St. Louis (average of $311). Flying from Boise to St. Louis in March is currently the most expensive (average of $356). 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

Traveling to a place near St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
O'Fallon
Maryland Heights
Fairview Heights
Collinsville
Eureka
St. Peters
Glencoe
Alton
Chesterfield
Festus
Farmington

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Top 5 airlines flying from Boise to St. Louis

Discover the top 5 airlines that operate flights from Boise to St. Louis. 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 July 29, 2025.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$226Average$402FlexibilityNo cancel feeOn-time71%
DeltaCheapest$226Average$365FlexibilityNo cancel feeOn-timeN/A
Alaska AirlinesCheapest$278Average$447FlexibilityNo cancel feeOn-time75%
SouthwestCheapest$286Average$448FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$292Average$422FlexibilityNo cancel feeOn-time69%

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