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$140+ 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 7/1. Fares are subject to change and may not be available on all flights or dates of travel.
BOI — STL
Jun 17 — Jun 241
Tue 6/17
Tue 6/24
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 June 12, 2025.

Round-trip from

$270
(Alaska Airlines)

One-way from

$140
(Delta)

Popular in

January

Cheapest in

April

Average price

$392
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. 18% potential increase in price ($96 potential increase over avg. RT price).
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Cheapest flight prices on average. 9% potential price decrease ($36 potential savings vs. average RT price).
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Average for round-trip flights in June 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 June 12, 2025.

This United Airlines deal was found by Cheapflights users on 6/10. 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 7/85:42 pmBOI - STL
1 stop5h 17mUnited Airlines
Tue 7/155:15 amSTL - BOI
1 stop5h 31mUnited Airlines
Deal found 6/10$279
This Delta deal was found by Cheapflights users on 6/11. 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 8/306:00 amBOI - STL
1 stop6h 29mDelta
Sun 8/317:35 amSTL - BOI
1 stop5h 20mDelta
Deal found 6/11$287
This American Airlines deal was found by Cheapflights users on 6/10. 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 8/15:17 pmBOI - STL
1 stop6h 11mAmerican Airlines
Tue 8/55:30 amSTL - BOI
1 stop6h 24mAmerican Airlines
Deal found 6/10$331
This Southwest deal was found by Cheapflights users on 6/10. 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.
Wed 7/25:05 amBOI - STL
2 stops12h 50mSouthwest
Sun 7/66:20 pmSTL - BOI
1 stop8h 00mSouthwest
Deal found 6/10$374
This Mytrip deal was found by Cheapflights users on 6/11. 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 6/267:14 pmBOI - STL
1 stop15h 22mMultiple Airlines
Sun 6/296:12 amSTL - BOI
2 stops27h 36mMultiple Airlines
Deal found 6/11$384
This Mytrip deal was found by Cheapflights users on 6/11. 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 6/267:14 pmBOI - STL
1 stop15h 22mSun Country Air
Sun 6/296:12 amSTL - BOI
1 stop11h 50mSun Country Air
Deal found 6/11$394
This Booking.com deal was found by Cheapflights users on 6/10. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/2612:36 pmBOI - STL
1 stop19h 36mFrontier
Sat 6/282:52 pmSTL - BOI
2 stops21h 55mFrontier
Deal found 6/10$484
This Alaska Airlines deal was found by Cheapflights users on 6/11. 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 6/266:00 amBOI - STL
2 stops16h 59mAlaska Airlines
Mon 6/303:24 pmSTL - BOI
1 stop9h 47mAlaska Airlines
Deal found 6/11$518
This Hawaiian Airlines deal was found by Cheapflights users on 6/10. 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.
Sat 6/146:25 amBOI - STL
1 stop7h 01mHawaiian Airlines
Mon 6/163:24 pmSTL - BOI
1 stop8h 22mHawaiian Airlines
Deal found 6/10$798

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 June 12, 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

Tue 7/8

5:42 pm-11:59 pm

1 stop5h 17m

Lambert-St Louis

Tue 7/15

5:15 am-9:46 am

1 stop5h 31m

$279

BoiseSt. Louis

BOI - STL

BOISTL

Boise Air Term. Gowen Fld

Sat 8/30

6:00 am-1:29 pm

1 stop6h 29m

Lambert-St Louis

Sun 8/31

7:35 am-11:55 am

1 stop5h 20m

$287

BoiseSt. Louis

BOI - STL

BOISTL

Boise Air Term. Gowen Fld

Fri 8/1

5:17 pm-12:28 am

1 stop6h 11m

Lambert-St Louis

Tue 8/5

5:30 am-10:54 am

1 stop6h 24m

$331

BoiseSt. Louis

BOI - STL

BOISTL

Boise Air Term. Gowen Fld

Wed 7/2

5:05 am-6:55 pm

2 stops12h 50m

Lambert-St Louis

Sun 7/6

6:20 pm-1:20 am

1 stop8h 00m

$374

BoiseSt. Louis

BOI - STL

BOISTL

Boise Air Term. Gowen Fld

Thu 6/26

7:14 pm-11:36 am

1 stop15h 22m

Lambert-St Louis

Sun 6/29

6:12 am-8:48 am

2 stops27h 36m

$384

BoiseSt. Louis

BOI - STL

BOISTL

Boise Air Term. Gowen Fld

Thu 6/26

7:14 pm-11:36 am

1 stop15h 22m

Lambert-St Louis

Sun 6/29

6:12 am-5:02 pm

1 stop11h 50m

$394

BoiseSt. Louis

BOI - STL

BOISTL

Boise Air Term. Gowen Fld

Thu 6/26

12:36 pm-9:12 am

1 stop19h 36m

Lambert-St Louis

Sat 6/28

2:52 pm-11:47 am

2 stops21h 55m

$484

BoiseSt. Louis

BOI - STL

BOISTL

Boise Air Term. Gowen Fld

Thu 6/26

6:00 am-11:59 pm

2 stops16h 59m

Lambert-St Louis

Mon 6/30

3:24 pm-12:11 am

1 stop9h 47m

$518

BoiseSt. Louis

BOI - STL

BOISTL

Boise Air Term. Gowen Fld

Tue 7/1

11:40 pm-9:15 am

1 stop8h 35m

$140

BoiseSt. Louis

BOI - STL

BOISTL

Boise Air Term. Gowen Fld

Tue 7/1

7:30 am-6:25 pm

2 stops9h 55m

$145

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/10

Showing 1-10 of 16 results
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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 June 9, 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 June 12, 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.

Rainfall in St. Louis by month

Plan your trip to St. Louis by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in St. Louis ranges from 2.2 - 4.7 inches per month. May is typically the wettest month, when rainfall can reach 4.7 in. February is typically the driest time to visit St. Louis when rainfall is around 2.2 in.

Temperature in St. Louis by month

Plan your trip to St. Louis by taking into account the average temperature totals by month.

If weather is an important factor for your trip to St. Louis, 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 80.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 32.0 F).

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 June 12, 2025.
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Food

7.1

Crew

8.5

Comfort

7.8

Overall

8.0

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Alaska Airlines
8.0
Very good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Food

7.1

Crew

8.5

Comfort

7.8

Overall

8.0

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Southwest
8.0
Very good
4,287 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Food

7.1

Crew

8.5

Comfort

7.8

Overall

8.0

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Delta
8.0
Very good
7,950 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Food

7.1

Crew

8.5

Comfort

7.8

Overall

8.0

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Hawaiian Airlines
7.9
Good
2,494 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Food

7.1

Crew

8.5

Comfort

7.8

Overall

8.0

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
United Airlines
7.4
Good
8,790 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Food

7.1

Crew

8.5

Comfort

7.8

Overall

8.0

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

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 $270, Alaska Airlines will fly you from Boise to St. Louis and back. In addition to Alaska Airlines, many other airlines offer competitively priced options for your trip. Search Cheapflights for deals from United Airlines and Delta - these airlines can fly you to your destination from $279 and $287, respectively. You may be able to fly from Boise to St. Louis for 38% 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 Delta ($140), Southwest ($145), and Sun Country Air ($155).

  • 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 Boise?

Book flights to Boise if you plan to visit one of these locations
O'Fallon
Maryland Heights
Fairview Heights
Collinsville
Eureka
St. Peters
Glencoe
Festus
Alton
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 June 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
DeltaCheapest$208Average$364FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$226Average$406FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$292Average$422FlexibilityNo cancel feeOn-time69%
Alaska AirlinesCheapest$326Average$447FlexibilityNo cancel feeOn-time75%
SouthwestCheapest$346Average$458FlexibilityNo cancel feeOn-time63%

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