
$99 Cheap United flights from Denver to St. Louis (DEN to STL)
Find The Best Day To Fly from Denver to St. Louis
Amazing United DEN to STL Flight Deals
The cheapest flights to Lambert-St. Louis Intl. found within the past 7 days were $177 round trip and $99 one way. Prices and availability subject to change. Additional terms may apply.
STL From DEN Economy Coach Packages on Similar Airlines



Frequently asked questions
Discover our best United flight from Denver DEN to St. Louis STL
To find the best deals on flights to Denver from St. Louis with United, just enter your travel dates, filter by United, and hit search. You’ll find 3 flights to choose from and can sort by price, flight duration, and arrival or departure time.
Return flights from Denver DEN to St. Louis STL with United
If you’re planning a round trip, booking return flights with United is usually the most cost-effective option. With airfares ranging from $177 to $177, it’s easy to find a flight that suits your budget. Prices and availability subject to change. Additional terms may apply.
Book one-way United flights from Denver DEN to St. Louis STL
A one-way ticket gives you much greater flexibility—allowing you to choose your return date, destination, and time whenever you’re ready. By booking in advance you can find great deals on one-way tickets too. Right now, a one-way United flight from Denver to St. Louis costs from $99. Prices and availability subject to change. Additional terms may apply.
The easy way to find cheap flights to St. Louis STL from Denver DEN with United
To find a cheap United flight from Denver DEN to St. Louis STL, sort your search results by price or filter by budget. Thanks to Travelocity’s Price Match Promise, if you find a better airfare deal anywhere else within 24 hours, we’ll credit or refund the difference.
How to find our best airfare deals on United flights from Denver DEN to St. Louis STL
If you’re looking for cheap flights, it helps to be flexible when it comes to your travel dates. You’ll usually find lower cost tickets when you travel during quieter months such as April, or if you book a flight with a stopover.
Find nonstop flights from Denver DEN to St. Louis STL with United
If you’re keen to be on St. Louis soil fast, don’t waste time with a stopover—filter your search results to show direct United flights only. The journey takes around 4 hour(s) 6 min(s) – so you’ll be there before you know it.
Flexible airline tickets for United flights from Denver DEN to St. Louis STL
Make sure you’re not out of pocket if plans change by choosing a flexible ticket with penalty-free amendment and cancellation options. Use our ‘no change fee’ filter to see which flights have this option.
There are a lot of reasons to book your flights to St. Louis STL from Denver DEN with United on Travelocity
At Travelocity our vast and up-to-the-minute inventory puts all of our best flight deals in one place. So, whether you’re traveling on business or jetting off with friends and family, you can trust Travelocity to get you there.
Airport code | Country | Airport name | Number of flights |
---|---|---|---|
ORD | USA | O'Hare Intl. | 227 |
DEN | USA | Denver Intl. | 226 |
IAH | USA | George Bush Intercontinental | 136 |
IAD | USA | Washington Dulles Intl. | 100 |
SFO | USA | San Francisco Intl. | 64 |
LAX | USA | Los Angeles Intl. | 23 |
EWR | USA | Liberty Intl. | 20 |
FRA | DEU | Frankfurt Intl. | 19 |
NRT | JPN | Narita Intl. | 19 |
PEK | CHN | Capital Intl. | 16 |
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Popular United Flight Routes from DEN
Top United Flight Routes from STL
Top Flights for United originating from DEN
Domestic
- Newark Liberty Intl. Airport to San Juan (EWR - SJU)
- Chicago to Las Vegas (ORD - LAS)
- Newark Liberty Intl. Airport to Santo Domingo (EWR - SDQ)
- Newark Liberty Intl. Airport to Atlanta (EWR - ATL)
- New York to Orlando (LGA - MCO)
- Boston to Orlando (BOS - MCO)
- Newark Liberty Intl. Airport to Fort Lauderdale (EWR - FLL)
- Newark Liberty Intl. Airport to Las Vegas (EWR - LAS)
- Newark Liberty Intl. Airport to Santiago (EWR - STI)
- Philadelphia to Orlando (PHL - MCO)
International
- Los Angeles to San Salvador (LAX - SAL)
- Newark Liberty Intl. Airport to Santo Domingo (EWR - SDQ)
- San Juan to Orlando (SJU - MCO)
- Chicago to Orlando (ORD - MCO)
- Newark Liberty Intl. Airport to Fort Lauderdale (EWR - FLL)
- Newark Liberty Intl. Airport to Santiago (EWR - STI)
- Philadelphia to San Juan (PHL - SJU)
- Newark Liberty Intl. Airport to San Juan (EWR - SJU)
- Newark Liberty Intl. Airport to Atlanta (EWR - ATL)
- Chicago to San Juan (ORD - SJU)