$126 Cheap United flights St. Louis (STL) to Sioux Falls (FSD)

View $126 flight on Sat, Sep 20, 2025Opens in a new window

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$126 Cheap United flights St. Louis (STL) to Sioux Falls (FSD)

Prices were available within the past 7 days and start at $126 for one-way flights and $229 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

United
Sat, Sep 20 - Sat, Sep 27
STL
St. Louis
FSD
Sioux Falls
$229 Roundtrip, just found
$229
Roundtrip
just found
Select United flight, departing Sat, Sep 20 from St. Louis to Sioux Falls, returning Sat, Sep 27, priced at $229 just found
United
Sat, Sep 20 - Fri, Sep 26
STL
St. Louis
FSD
Sioux Falls
$247 Roundtrip, found 1 day ago
$247
Roundtrip
found 1 day ago
Select United flight, departing Sat, Sep 20 from St. Louis to Sioux Falls, returning Fri, Sep 26, priced at $247 found 1 day ago
United
Fri, Aug 8 - Fri, Aug 15
STL
St. Louis
FSD
Sioux Falls
$249 Roundtrip, found 13 hours ago
$249
Roundtrip
found 13 hours ago
Select United flight, departing Fri, Aug 8 from St. Louis to Sioux Falls, returning Fri, Aug 15, priced at $249 found 13 hours ago
United
Sat, Sep 20 - Sat, Sep 27
STL
St. Louis
FSD
Sioux Falls
$259 Roundtrip, just found
$259
Roundtrip
just found
Select United flight, departing Sat, Sep 20 from St. Louis to Sioux Falls, returning Sat, Sep 27, priced at $259 just found
United
Thu, Jul 10 - Tue, Jul 15
STL
St. Louis
FSD
Sioux Falls
$260 Roundtrip, found 6 days ago
$260
Roundtrip
found 6 days ago
Select United flight, departing Thu, Jul 10 from St. Louis to Sioux Falls, returning Tue, Jul 15, priced at $260 found 6 days ago
United
Sat, Sep 20 - Fri, Sep 26
STL
St. Louis
FSD
Sioux Falls
$263 Roundtrip, found 1 day ago
$263
Roundtrip
found 1 day ago
Select United flight, departing Sat, Sep 20 from St. Louis to Sioux Falls, returning Fri, Sep 26, priced at $263 found 1 day ago
Flights from St. Louis (STL) to Sioux Falls (FSD)
Origin airport
Lambert-St. Louis Intl.
Destination airport
Sioux Falls Regional
Airlines serving
American Airlines, Delta, Frontier Airlines, United
Popular airline
Delta
Distance
470 mi

Frequently asked questions

How much is a United Airlines flight from Lambert-St. Louis Intl. Airport (STL) to Sioux Falls Regional Airport (FSD)?
Make use of the "Price (lowest to highest)" filter on Expedia to search for cheap United Airlines return flights from $229 from STL to FSD. Affordable one-way fares from $126 are available as well.**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 FSD with United Airlines?
January is one of the least expensive months to jet away to Sioux Falls with United Airlines. You could also find great deals on one-way and return fares in December.
What is the cheapest time to book flights from Lambert-St. Louis Intl. Airport (STL) to Sioux Falls Regional Airport (FSD) with United Airlines?
Start searching one to three months ahead of your departure date to find cheap fares on United Airlines flights from Lambert-St. Louis Intl. Airport (STL) to Sioux Falls Regional Airport (FSD). You can save 25% by booking your domestic flight 34 to 86 days in advance compared to last-minute reservations made 6 to 12 days out. You could also reduce costs by buying your fare on a Sunday, as it's 6% cheaper on average than a Monday, the most expensive day to book.* Get your timing right, and you can enjoy significant savings on domestic journeys.*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 United Airlines fly nonstop from Lambert-St. Louis Intl. Airport (STL) to Sioux Falls Regional Airport (FSD)?
Simply enter your dates, click search and select "Nonstop" on Expedia to browse any direct flights from STL to FSD with United Airlines or another airline.
What is the earliest United Airlines flight from STL to FSD?
Search United Airlines's earliest flights from STL to FSD by selecting the "Morning" and "Early Morning" filters. Not only will you arrive sooner, early departures are also 20% less likely to be canceled.**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 United Airlines fly into in Sioux Falls?
United Airlines flights from Lambert-St. Louis Intl. Airport (STL) to Sioux Falls come in to land at Sioux Falls Regional Airport (FSD). This is the main gateway to this city.
Why fly with United Airlines from STL to FSD?
A rewarding loyalty program and the ability to rack up points through United Mileage Plus are the start of the reasons to leave from STL to FSD with United Airlines. Plus, by joining Expedia's free One Key™ program, you can receive OneKeyCash™* in addition to United Airlines's loyalty program earnings. It's yours to spend on future travel plans.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.
Can I change or cancel my United Airlines flight from Lambert-St. Louis Intl. Airport (STL) to Sioux Falls Regional Airport (FSD)?
Depending on your ticket type, a fee generally applies if you cancel or reschedule your flight more than 24 hours after it's been confirmed. To secure tickets with more flexibility, select our "No cancel fee" or "Changes included" filter when you look for flights. For additional information on modifying or canceling your reservation, head to "Trips," select your flight and tick "Manage Booking."

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