$99 Cheap United flights from St. Louis to Denver (STL to DEN)

Find The Best Day To Fly from St. Louis to Denver

Amazing United STL to DEN Flight Deals

The cheapest flights to Denver Intl. found within the past 7 days were $168 round trip and $99 one way. Prices and availability subject to change. Additional terms may apply.

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Frequently asked questions

Can I catch a flight from Lambert Field to DEN right now?
It’s always wise to know about any travel advice reports and quarantine requirements in effect in your destination city. Be sure to visit the Covid-19 Travel Advisor for up-to-date info on booking a flight to DIA airport.
What terminal is United Airlines at St. Louis Lambert International Airport?
If you’re flying with United Airlines from STL, you’ll usually catch your flight from terminal 1. If you’re heading to DIA airport from here, you’ll probably be filing off the aircraft at the main terminal.
Are there United Airlines non-stop flights from STL to DEN?
There certainly are. Save time and fly straight from St. Louis Lambert International Airport to Denver Airport with United Airlines. Avoid layovers, lessen the risk of losing your belongings and arrive at your destination faster — direct flights are preferred by many wise wanderers.
How long is a United Airlines flight from STL to DEN?
Your United Airlines flight will get you from St. Louis Lambert International Airport to Denver Intl. Airport (DEN) in roughly 3 hours and 27 minutes. If you’re not a big fan of talking to other travelers while you’re high up in the air, don’t stress — you won’t have to natter for too long.
What type of aircraft does United Airlines fly from STL to DEN?
If you’re journeying from STL to DEN with United Airlines, you’ll probably be cruising the skies aboard the Airbus A319 or the Bombardier CRJ700.
How many direct and indirect flights does United Airlines fly from STL to DEN?
You’ll have a choice of 5 flights every day with United Airlines from STL to DIA airport.
If I am not able to travel due to COVID-19, can I change my booking to a later date?
For more info about changing your flight to Denver Airport, please visit our Customer Service Portal.
What is the best day to buy a plane ticket?
This just in! Airfares offered on Thursdays tend to be the cheapest, according to flight demand on Travelocity in 2021. Tuesday and Wednesday prices are also good, but you may want to prepare your budget if booking during the weekend, as data shows that is when prices are generally at their highest.
What are the cheapest days to fly?
Frequent travelers may already know this, but earlier in the week can be the cheapest time to fly. In 2021, flights departing on a Monday were generally the cheapest of the week, whereas you may pay a premium for weekend flights when demand is usually high. On average, tickets were most expensive for Saturday departures, so if you need to fly out on a weekend, you might look for deals ahead of time.
How far in advance can you book a flight?
Trying to figure out how early you should book your flight? It’s possible to start comparing international airfares on Travelocity up to 12 months in advance. However, it does depend on the carrier as not all airlines release their prices that far out. According to our 2021 flight demand trends, last minute planners can still bag a bargain with some of the cheapest fares appearing 0-2 weeks prior to their travel dates.*According to flight demand on Travelocity.com from January to December 2021. Savings are subject to change based on departure location, date and destination.

Discover our best United flight from St. Louis STL to Denver DEN 

To find the best deals on flights to St. Louis from Denver with United, just enter your travel dates, filter by United, and hit search. You’ll find 4 flights to choose from and can sort by price, flight duration, and arrival or departure time.  

 

Return flights from St. Louis STL to Denver DEN 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 $168 to $225, 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 St. Louis STL to Denver DEN 

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 St. Louis to Denver costs from $99. Prices and availability subject to change. Additional terms may apply. 

 

The easy way to find cheap flights to Denver DEN from  St. Louis STL with United 

To find a cheap United flight from St. Louis STL to Denver DEN, 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 St. Louis STL to Denver DEN 

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 May, or if you book a flight with a stopover. 

 

Find nonstop flights from St. Louis STL to Denver DEN with United 

If you’re keen to be on Denver soil fast, don’t waste time with a stopover—filter your search results to show direct United flights only. The journey takes around 2 hour(s) 29 min(s) – so you’ll be there before you know it. 

 

Flexible airline tickets for United flights from St. Louis STL to Denver DEN 

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 Denver DEN from  St. Louis STL 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.

United Airports
Hop on a(n) United flight today by flying to many destinations out of these domestic and international airports:
Airport code
Country
Airport name
Number of flights
ORDUSAO'Hare Intl.227
DENUSADenver Intl.226
IAHUSAGeorge Bush Intercontinental136
IADUSAWashington Dulles Intl.100
SFOUSASan Francisco Intl.64
LAXUSALos Angeles Intl.23
EWRUSALiberty Intl.20
FRADEUFrankfurt Intl.19
NRTJPNNarita Intl.19
PEKCHNCapital Intl.16

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