$138 Cheap Flights from St. Louis (STL) to Missoula (MSO)

View $138 flight on Mon, Jan 26, 2026Opens in a new window

Popular airlines from St. Louis Lambert Intl. Airport (STL) to Missoula Intl. Airport (MSO)

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Cheap Flights from St. Louis to Missoula (STL-MSO)

Prices were available within the past 7 days and start at $138 for one-way flights and $275 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Alaska Airlines
Wed, Jan 21 - Wed, Jan 28
STL
St. Louis
MSO
Missoula
$275 Roundtrip, found 1 hour ago
$275
Roundtrip
found 1 hour ago
Select Alaska Airlines flight, departing Wed, Jan 21 from St. Louis to Missoula, returning Wed, Jan 28, priced at $275 found 1 hour ago
Hawaiian Airlines
Tue, Feb 10 - Mon, Feb 16
STL
St. Louis
MSO
Missoula
$318 Roundtrip, found 2 days ago
$318
Roundtrip
found 2 days ago
Select Hawaiian Airlines flight, departing Tue, Feb 10 from St. Louis to Missoula, returning Mon, Feb 16, priced at $318 found 2 days ago
Alaska Airlines
Wed, Jan 21 - Wed, Jan 28
STL
St. Louis
MSO
Missoula
$323 Roundtrip, found 1 hour ago
$323
Roundtrip
found 1 hour ago
Select Alaska Airlines flight, departing Wed, Jan 21 from St. Louis to Missoula, returning Wed, Jan 28, priced at $323 found 1 hour ago
United
Wed, Jan 14 - Mon, Jan 26
STL
St. Louis
MSO
Missoula
$323 Roundtrip, found 2 days ago
$323
Roundtrip
found 2 days ago
Select United flight, departing Wed, Jan 14 from St. Louis to Missoula, returning Mon, Jan 26, priced at $323 found 2 days ago
Delta
Wed, Jan 14 - Mon, Jan 26
STL
St. Louis
MSO
Missoula
$325 Roundtrip, found 2 days ago
$325
Roundtrip
found 2 days ago
Select Delta flight, departing Wed, Jan 14 from St. Louis to Missoula, returning Mon, Jan 26, priced at $325 found 2 days ago
Frontier Airlines
Sun, Oct 12 - Mon, Oct 20
STL
St. Louis
MSO
Missoula
$326 Roundtrip, found 5 days ago
$326
Roundtrip
found 5 days ago
Select Frontier Airlines flight, departing Sun, Oct 12 from St. Louis to Missoula, returning Mon, Oct 20, priced at $326 found 5 days ago
United
Wed, Jan 14 - Mon, Jan 26
STL
St. Louis
MSO
Missoula
$328 Roundtrip, found 2 days ago
$328
Roundtrip
found 2 days ago
Select United flight, departing Wed, Jan 14 from St. Louis to Missoula, returning Mon, Jan 26, priced at $328 found 2 days ago
United
Wed, Jan 14 - Mon, Jan 26
STL
St. Louis
MSO
Missoula
$331 Roundtrip, found 2 days ago
$331
Roundtrip
found 2 days ago
Select United flight, departing Wed, Jan 14 from St. Louis to Missoula, returning Mon, Jan 26, priced at $331 found 2 days ago
Bargain Flight
Fri, Feb 13 - Mon, Feb 16
STL
St. Louis
MSO
Missoula
$338 Roundtrip, found 2 days ago
$338
Roundtrip
found 2 days ago
Select Bargain Flight flight, departing Fri, Feb 13 from St. Louis to Missoula, returning Mon, Feb 16, priced at $338 found 2 days ago
Delta
Sun, Jan 11 - Sun, Jan 25
STL
St. Louis
MSO
Missoula
$342 Roundtrip, found 2 days ago
$342
Roundtrip
found 2 days ago
Select Delta flight, departing Sun, Jan 11 from St. Louis to Missoula, returning Sun, Jan 25, priced at $342 found 2 days ago

Find the cheapest month to fly from St. Louis (STL) to Missoula (MSO)

October is typically the cheapest month to fly

From $286 - $702 per traveler.

Frequently asked questions

How much does a flight from Lambert-St. Louis Intl. Airport (STL) to Missoula Intl. Airport (MSO) cost?
Secure a cheap one-way flight from $138 or cheap return flight from $275 from Lambert-St. Louis Intl. Airport (STL) to Missoula Intl. Airport (MSO) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to see our cheapest flight deals on this route.
What is the cheapest month to fly from Lambert-St. Louis Intl. Airport (STL) to Missoula Intl. Airport (MSO)?
The cheapest month to fly from STL to MSO is January, when demand is low. Off-peak season is generally when airlines offer lower prices between these airports.
What is the cheapest airline that flies from Lambert-St. Louis Intl. Airport (STL) to Missoula Intl. Airport (MSO)?
Expedia's filter tool lets you easily compare airlines, flight times and baggage options all in one place. Choose your preferences, then sort by "Price (lowest to highest)" to find out which carrier offers the cheapest STL to MSO flight.
How many flights per day from Lambert-St. Louis Intl. Airport (STL) to Missoula Intl. Airport (MSO)?
There are no daily direct flights available from Lambert-St. Louis Intl. Airport (STL) to Missoula Intl. Airport (MSO). But you can book flights with layovers. Filter your search on Expedia to include one or more stops, and you'll be cruising above the clouds before you know it.
What day of the week has the most flights from STL to MSO?
Generally you'll find the widest variety of flight choices on a Friday. Tuesdays tend to be the quietest.* But this can vary based on the season, airline and other factors.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Lambert-St. Louis Intl. Airport (STL) to Missoula Intl. Airport (MSO)?
Select a flight from Lambert-St. Louis Intl. Airport (STL) to Missoula Intl. Airport (MSO) that takes off before 3 PM to reduce the risk of delays and cancellations. Departures later than this are on average 22% more likely to be canceled.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
Is it cheaper to buy a plane ticket from Lambert-St. Louis Intl. Airport (STL) to Missoula Intl. Airport (MSO) last-minute?
Booking your plane ticket from STL to MSO shortly before your trip is typically more expensive. But if you're flexible with your travel dates and times, you could grab a cheap last-minute fare.
Is it cheaper to book a STL to MSO flight and hotel package?
You'll generally save money by securing a STL to MSO flight and hotel package compared to booking separately. In fact, travelers could save hundreds of dollars by bundling with Expedia. And it's easy to manage it all in one place. Once you've selected your ideal flights and accommodations, consider adding extras including car rentals, activities and tours.
Can I cancel or change the date of my flight from Lambert-St. Louis Intl. Airport (STL) to Missoula Intl. Airport (MSO)?
In most instances, you're able to reschedule or cancel your STL to MSO flight. However, additional charges may apply, especially if you made your booking more than 24 hours ago. Check your itinerary for the airline's guidelines and fees on flight changes, or if you want more details, head to our Customer Service portal.

Travel information

Travel information

Origin airport
Lambert-St. Louis Intl.
Destination airport
Missoula Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, Hawaiian Airlines, United
Roundtrip price
$274
Distance
1320 mi

Book with confidence

Book with confidence

St. Louis to Missoula Flights

The cheapest times to fly from St. Louis to Missoula

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from St. Louis to Missoula are during the month of January. You can find some of the cheapest flights from St. Louis to Missoula with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from St. Louis to Missoula

Sunday is one of the best days to book for cheap flights from St. Louis to Missoula: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from St. Louis to Missoula

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from St. Louis to Missoula in 2025. You can also book with separate airlines for your outbound and return journeys, from $138 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap St. Louis to Missoula flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your St. Louis to Missoula airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

St. Louis to Missoula Flights

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*Available to One Key members.