Cheap flights from St. Louis to Mountain States

View AU$136 flight on Sat, 16 Aug. 2025Opens in a new window

Popular airlines from St. Louis to Mountain States

  • American Airlines

    American Airlines

  • Alaska Airlines

    Alaska Airlines

  • Delta

    Delta

  • United

    United

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Cheap Flights from St. Louis (STL) to Mountain States (DEN)

Prices were available within the past 7 days for one-way flights and round trip tickets for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Sat, 16 Aug. - Mon, 18 Aug.
STL
St. Louis
DEN
Denver
AU$302 Return, found 10 hours ago
AU$302
Return
found 10 hours ago
Select Delta flight, departing Sat, 16 Aug. from St. Louis to Denver, returning Mon, 18 Aug., priced at AU$302 found 10 hours ago
Delta
Sat, 16 Aug. - Mon, 18 Aug.
STL
St. Louis
DEN
Denver
AU$326 Return, found 10 hours ago
AU$326
Return
found 10 hours ago
Select Delta flight, departing Sat, 16 Aug. from St. Louis to Denver, returning Mon, 18 Aug., priced at AU$326 found 10 hours ago
American Airlines
Sun, 31 Aug. - Sun, 7 Sep.
STL
St. Louis
DEN
Denver
AU$332 Return, found 6 days ago
AU$332
Return
found 6 days ago
Select American Airlines flight, departing Sun, 31 Aug. from St. Louis to Denver, returning Sun, 7 Sep., priced at AU$332 found 6 days ago
United
Sat, 16 Aug. - Mon, 18 Aug.
STL
St. Louis
DEN
Denver
AU$348 Return, found 10 hours ago
AU$348
Return
found 10 hours ago
Select United flight, departing Sat, 16 Aug. from St. Louis to Denver, returning Mon, 18 Aug., priced at AU$348 found 10 hours ago
United
Sat, 16 Aug. - Mon, 18 Aug.
STL
St. Louis
DEN
Denver
AU$363 Return, found 10 hours ago
AU$363
Return
found 10 hours ago
Select United flight, departing Sat, 16 Aug. from St. Louis to Denver, returning Mon, 18 Aug., priced at AU$363 found 10 hours ago
Alaska Airlines
Thu, 14 Aug. - Fri, 22 Aug.
STL
St. Louis
MSO
Missoula
AU$603 Return, found 3 days ago
AU$603
Return
found 3 days ago
Select Alaska Airlines flight, departing Thu, 14 Aug. from St. Louis to Missoula, returning Fri, 22 Aug., priced at AU$603 found 3 days ago

Find the cheapest month to fly from St. Louis (STL) to Las Vegas (LAS)

August is typically the cheapest month to fly

From AU$107 - AU$344 per traveller.

Graph displaying average flight prices per month

*Available to Expedia members.