$140 Cheap American Airlines flights St. Louis (STL) to Boise (BOI)

View $140 flight on Sat, Sep 20, 2025Opens in a new window

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$140 Cheap American Airlines flights St. Louis (STL) to Boise (BOI)

Prices were available within the past 7 days and start at $140 for one-way flights and $279 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

American Airlines
Sat, Sep 20 - Mon, Sep 22
STL
St. Louis
BOI
Boise
$279 Roundtrip, just found
$279
Roundtrip
just found
Select American Airlines flight, departing Sat, Sep 20 from St. Louis to Boise, returning Mon, Sep 22, priced at $279 just found
American Airlines
Mon, Aug 11 - Fri, Aug 15
STL
St. Louis
BOI
Boise
$301 Roundtrip, found 4 hours ago
$301
Roundtrip
found 4 hours ago
Select American Airlines flight, departing Mon, Aug 11 from St. Louis to Boise, returning Fri, Aug 15, priced at $301 found 4 hours ago
American Airlines
Fri, Sep 26 - Tue, Sep 30
STL
St. Louis
BOI
Boise
$305 Roundtrip, found 5 days ago
$305
Roundtrip
found 5 days ago
Select American Airlines flight, departing Fri, Sep 26 from St. Louis to Boise, returning Tue, Sep 30, priced at $305 found 5 days ago
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Flights from St. Louis (STL) to Boise (BOI)
Origin airport
Lambert-St. Louis Intl.
Destination airport
Boise
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, Hawaiian Airlines, Southwest Airlines, United
Popular airline
Alaska Airlines
Distance
1379 mi

Frequently asked questions

How much is an American Airlines flight from Lambert-St. Louis Intl. Airport (STL) to Boise Airport (BOI)?
Make use of the "Price (lowest to highest)" filter on Expedia to find cheap American Airlines round-trip flights from $279 from STL to BOI. Affordable one-way fares from $140 are available too.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.
What is the cheapest month to fly from STL to BOI with American Airlines?
Look for return or one-way flights to Boise in January or December. You could find cheaper fares with American Airlines during these off-peak months.
What is the cheapest time to book flights from Lambert-St. Louis Intl. Airport (STL) to Boise Airport (BOI) with American Airlines?
Search for cheap American Airlines flights from Lambert-St. Louis Intl. Airport (STL) to Boise Airport (BOI) one to three months before your departure. Travelers who book domestic flights 34 to 86 days in advance can save 25% compared to those who book just 6 to 12 days ahead. Regardless of fare type and itinerary, the best day of the week to book a domestic flight is usually Sunday and the most expensive tends to be Monday. Passengers who book on a Sunday can save 6% on average compared to those who book their travel on a Monday.**Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC's global airline sales database.
Does American Airlines fly nonstop from Lambert-St. Louis Intl. Airport (STL) to Boise Airport (BOI)?
To find out if there's a direct trip from STL to BOI with American Airlines or other carriers, check the "Nonstop" box when browsing for flights.
What is the earliest American Airlines flight from STL to BOI?
To find the earliest departure from STL to BOI with American Airlines, filter your results by "Early Morning" and "Morning." Choosing an early flight usually means you'll experience fewer cancellations.**Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
What airports does American Airlines fly into in Boise?
American Airlines flights from Lambert-St. Louis Intl. Airport (STL) to Boise come in to Boise Airport (BOI). This is the main gateway to this destination.
Can I change or cancel my American Airlines flight from Lambert-St. Louis Intl. Airport (STL) to Boise Airport (BOI)?
It's generally possible to cancel or reschedule your flight, although additional charges may apply if you booked over 24 hours ago. Need to keep your options open? Apply the "No cancel fee" and "Changes included" filters to find flights that won't penalize you if you have to adjust your plans. To make modifications, go to "Trips," select your flight and click on "Manage Booking" for more details.

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