$79 Cheap Flights from St. Louis (STL) to Austin (AUS)

View $79 flight on Thu, Dec 18, 2025Opens in a new window

Popular airlines from St. Louis Lambert Intl. Airport (STL) to Austin-Bergstrom Intl. Airport (AUS)

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Cheap Flights from St. Louis to Austin (STL-AUS)

Prices were available within the past 7 days and start at $79 for one-way flights and $157 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Southwest Airlines
Wed, Sep 10 - Sat, Sep 13
STL
St. Louis
AUS
Austin
$157 Roundtrip, found 8 hours ago
$157
Roundtrip
found 8 hours ago
Select Southwest Airlines flight, departing Wed, Sep 10 from St. Louis to Austin, returning Sat, Sep 13, priced at $157 found 8 hours ago
Southwest Airlines
Sat, Sep 20 - Mon, Sep 22
STL
St. Louis
AUS
Austin
$167 Roundtrip, found 5 hours ago
$167
Roundtrip
found 5 hours ago
Select Southwest Airlines flight, departing Sat, Sep 20 from St. Louis to Austin, returning Mon, Sep 22, priced at $167 found 5 hours ago
Southwest Airlines
Sat, Sep 20 - Mon, Sep 22
STL
St. Louis
AUS
Austin
$169 Roundtrip, found 5 hours ago
$169
Roundtrip
found 5 hours ago
Select Southwest Airlines flight, departing Sat, Sep 20 from St. Louis to Austin, returning Mon, Sep 22, priced at $169 found 5 hours ago
Spirit Airlines
Thu, Nov 6 - Sat, Nov 8
STL
St. Louis
AUS
Austin
$171 Roundtrip, found 2 days ago
$171
Roundtrip
found 2 days ago
Select Spirit Airlines flight, departing Thu, Nov 6 from St. Louis to Austin, returning Sat, Nov 8, priced at $171 found 2 days ago
United
Tue, Dec 30 - Mon, Jan 5
STL
St. Louis
AUS
Austin
$172 Roundtrip, found 7 hours ago
$172
Roundtrip
found 7 hours ago
Select United flight, departing Tue, Dec 30 from St. Louis to Austin, returning Mon, Jan 5, priced at $172 found 7 hours ago
American Airlines
Sat, Aug 30 - Sat, Aug 30
STL
St. Louis
AUS
Austin
$173 Roundtrip, found 1 day ago
$173
Roundtrip
found 1 day ago
Select American Airlines flight, departing Sat, Aug 30 from St. Louis to Austin, returning Sat, Aug 30, priced at $173 found 1 day ago
Spirit Airlines
Thu, Oct 9 - Mon, Oct 13
STL
St. Louis
AUS
Austin
$176 Roundtrip, found 12 hours ago
$176
Roundtrip
found 12 hours ago
Select Spirit Airlines flight, departing Thu, Oct 9 from St. Louis to Austin, returning Mon, Oct 13, priced at $176 found 12 hours ago
Delta
Thu, Aug 21 - Sat, Aug 23
STL
St. Louis
AUS
Austin
$177 Roundtrip, found 12 hours ago
$177
Roundtrip
found 12 hours ago
Select Delta flight, departing Thu, Aug 21 from St. Louis to Austin, returning Sat, Aug 23, priced at $177 found 12 hours ago
Southwest Airlines
Sat, Sep 20 - Mon, Sep 22
STL
St. Louis
AUS
Austin
$179 Roundtrip, found 5 hours ago
$179
Roundtrip
found 5 hours ago
Select Southwest Airlines flight, departing Sat, Sep 20 from St. Louis to Austin, returning Mon, Sep 22, priced at $179 found 5 hours ago
Spirit Airlines
Thu, Sep 18 - Sat, Sep 20
STL
St. Louis
AUS
Austin
$181 Roundtrip, found 3 days ago
$181
Roundtrip
found 3 days ago
Select Spirit Airlines flight, departing Thu, Sep 18 from St. Louis to Austin, returning Sat, Sep 20, priced at $181 found 3 days ago

Find the cheapest month to fly from St. Louis (STL) to Austin (AUS)

October is typically the cheapest month to fly

From $157 - $491 per traveler.

Graph displaying average flight prices per month

Alternative airports near Austin

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to Austin-Bergstrom Intl. AUS. Cheapest and Closest option available. Average driving time to city center is 11 minutes. Flights from $309
AUS
Austin-Bergstrom Intl.
CheapestClosest
Average driving time to city center11 min
Flights from $309
Flights from St. Louis (STL) to Austin (AUS)
Origin airport
Lambert-St. Louis Intl.
Destination airport
Austin-Bergstrom Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, Southwest Airlines, Spirit Airlines, United
Roundtrip price
$157
Distance
721 mi
Average flight time
2 hours 14 mins

St. Louis to Austin Flights

The cheapest times to fly from St. Louis to Austin

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 Austin are during the month of September. You can find some of the cheapest flights from St. Louis to Austin with Expedia's search tool and vast selection of airlines.

 

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

Sunday is one of the best days to book for cheap flights from St. Louis to Austin: 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 Austin

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 Austin in 2025. You can also book with separate airlines for your outbound and return journeys, from $79 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 Austin 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 Austin 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.

 

Frequently asked questions

How much does a flight from Lambert-St. Louis Intl. Airport (STL) to Austin-Bergstrom Intl. Airport (AUS) cost?
Cheap round-trip flights from Lambert-St. Louis Intl. Airport (STL) to Austin-Bergstrom Intl. Airport (AUS) start at $157. This information is based on the cheapest price found on Expedia for this return journey departing within the next three months. This airfare is for a Southwest Airlines flight leaving STL on August 12 2025 and touching down at AUS. The price was last updated on July 23 2025 and has not changed since.
What is the cheapest month to fly from STL to AUS?
The cheapest flights from STL to AUS are usually during off-peak season, when demand is lower. To save money, avoid flying during public holidays, school breaks and major local events.
Which airlines fly direct from Lambert-St. Louis Intl. Airport (STL) to Austin-Bergstrom Intl. Airport (AUS)?
Hop on a direct flight with Southwest Airlines and go straight from Lambert-St. Louis Intl. Airport (STL) to Austin-Bergstrom Intl. Airport (AUS).
What is the cheapest airline that flies from STL to AUS?
With fares starting at $79 for a one-way journey from STL to AUS, Southwest Airlines is currently the cheapest airline on this route. This fare is based on the lowest price found on Expedia departing within the next three months. The flight takes off from STL on October 15 2025. Prices were last updated on July 23 2025 and have not changed since.
How many flights per day from Lambert-St. Louis Intl. Airport (STL) to Austin-Bergstrom Intl. Airport (AUS)?
On average, Lambert-St. Louis Intl. Airport (STL) only offers 1 direct flight to Austin-Bergstrom Intl. Airport (AUS) each day. For more options, try Expedia's easy-to-use filter tool. Simply enter your details, then select "1 Stop" or "2+ Stops" to discover flights offering layovers.
What are the most popular departure times for flights from Lambert-St. Louis Intl. Airport (STL) to Austin-Bergstrom Intl. Airport (AUS)?
Flights between STL and AUS are their busiest at 11 AM. If you'd like a more relaxed experience and potentially cheaper fares, choose a time outside the usual busy windows.
What day of the week has the most flights from STL to AUS?
Friday offers the most flights from Lambert-St. Louis Intl. Airport (STL) to Austin-Bergstrom Intl. Airport (AUS). Consider leaving on this day and you'll have a greater chance of finding a departure that fits your plans.
What is the earliest flight from Lambert-St. Louis Intl. Airport (STL) to Austin-Bergstrom Intl. Airport (AUS)?
Hop on the earliest flight at around 10:25AM UTC-6, departing from Lambert-St. Louis Intl. Airport (STL). You'll be flying for around 2h 15m, landing at Austin-Bergstrom Intl. Airport (AUS) at approximately 12:40PM UTC-6.
How long does it take to fly from Lambert-St. Louis Intl. Airport (STL) to Austin-Bergstrom Intl. Airport (AUS)?
It takes around 2 hours and 15 minutes to travel the 720 mi from STL to AUS.
What airline has the least delays from STL to AUS?
With 84% of journeys typically arriving as scheduled, American Airlines has the best on-time performance for direct flights from Lambert-St. Louis Intl. Airport (STL) to Austin-Bergstrom Intl. Airport (AUS). To keep track of your flight status and receive notifications about any changes, head to the Expedia App.
What is the best time to fly from Lambert-St. Louis Intl. Airport (STL) to Austin-Bergstrom Intl. Airport (AUS)?
To avoid possible delays on the Lambert-St. Louis Intl. Airport (STL) to Austin-Bergstrom Intl. Airport (AUS) route, travel before 3 PM. Departures after this hour have a 22% higher chance of cancellation.**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.
What airports do you fly into for Austin from Lambert-St. Louis Intl. Airport (STL)?
Austin-Bergstrom Intl. Airport (AUS) is the only airport in Austin with direct flights from Lambert-St. Louis Intl. Airport (STL). Explore the options and discover cheap fares on Expedia.
Is it cheaper to buy a plane ticket from Lambert-St. Louis Intl. Airport (STL) to Austin-Bergstrom Intl. Airport (AUS) last-minute?
Holding off until right before your break to book a flight from STL to AUS generally means paying more. While you may come across some last-minute deals, they aren't always guaranteed. Be flexible with your travel plans for the best chance of scoring a bargain.
Is it cheaper to book a STL to AUS flight and hotel package?
You'll generally save money by booking a STL to AUS 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 everything in one place. Once you've selected your preferred accommodations and flights, consider adding extras like car rentals, tours and activities.
Can I cancel or change the date of my flight from Lambert-St. Louis Intl. Airport (STL) to Austin-Bergstrom Intl. Airport (AUS)?
In most instances, you can modify or cancel your STL to AUS flight. However, there may be additional fees, especially if you booked over 24 hours ago. Double-check your itinerary for the airline's policies and fees on flight changes, or if you'd like further details, head to our Customer Service portal.

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