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£213 Cheap Flights from St. Louis (STL) to Denver (DEN)

View £213 flight on Thu, 10 Sept 2026Opens in a new window

Popular airlines from Lambert-St. Louis International Airport (STL) to Denver International Airport (DEN)

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Cheap Flights from St. Louis (STL) to Denver (DEN)

Prices were available within the past 7 days and start at £213 for one-way flights and £385 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Alaska Airlines
Thu, 24 Sept - Mon, 28 Sept
STL
St. Louis
DEN
Denver
£385 Return, found 1 day ago
£385
Return
found 1 day ago
Select Alaska Airlines flight, departing Thu, 24 Sept from St. Louis to Denver, returning Mon, 28 Sept, priced at £385 found 1 day ago
Alaska Airlines
Fri, 2 Oct - Mon, 5 Oct
STL
St. Louis
DEN
Denver
£398 Return, found 1 day ago
£398
Return
found 1 day ago
Select Alaska Airlines flight, departing Fri, 2 Oct from St. Louis to Denver, returning Mon, 5 Oct, priced at £398 found 1 day ago
Alaska Airlines
Thu, 24 Sept - Mon, 28 Sept
STL
St. Louis
DEN
Denver
£403 Return, found 1 day ago
£403
Return
found 1 day ago
Select Alaska Airlines flight, departing Thu, 24 Sept from St. Louis to Denver, returning Mon, 28 Sept, priced at £403 found 1 day ago
Alaska Airlines
Fri, 2 Oct - Mon, 5 Oct
STL
St. Louis
DEN
Denver
£413 Return, found 1 day ago
£413
Return
found 1 day ago
Select Alaska Airlines flight, departing Fri, 2 Oct from St. Louis to Denver, returning Mon, 5 Oct, priced at £413 found 1 day ago
Alaska Airlines
Thu, 24 Sept - Mon, 28 Sept
STL
St. Louis
DEN
Denver
£415 Return, found 1 day ago
£415
Return
found 1 day ago
Select Alaska Airlines flight, departing Thu, 24 Sept from St. Louis to Denver, returning Mon, 28 Sept, priced at £415 found 1 day ago
Alaska Airlines
Thu, 6 Aug - Wed, 12 Aug
STL
St. Louis
DEN
Denver
£418 Return, found 1 day ago
£418
Return
found 1 day ago
Select Alaska Airlines flight, departing Thu, 6 Aug from St. Louis to Denver, returning Wed, 12 Aug, priced at £418 found 1 day ago
Alaska Airlines
Thu, 10 Sept - Sun, 13 Sept
STL
St. Louis
DEN
Denver
£423 Return, found 1 day ago
£423
Return
found 1 day ago
Select Alaska Airlines flight, departing Thu, 10 Sept from St. Louis to Denver, returning Sun, 13 Sept, priced at £423 found 1 day ago
Alaska Airlines
Thu, 6 Aug - Wed, 12 Aug
STL
St. Louis
DEN
Denver
£430 Return, found 1 day ago
£430
Return
found 1 day ago
Select Alaska Airlines flight, departing Thu, 6 Aug from St. Louis to Denver, returning Wed, 12 Aug, priced at £430 found 1 day ago
Alaska Airlines
Fri, 2 Oct - Mon, 5 Oct
STL
St. Louis
DEN
Denver
£431 Return, found 1 day ago
£431
Return
found 1 day ago
Select Alaska Airlines flight, departing Fri, 2 Oct from St. Louis to Denver, returning Mon, 5 Oct, priced at £431 found 1 day ago
Alaska Airlines
Thu, 24 Sept - Mon, 28 Sept
STL
St. Louis
DEN
Denver
£433 Return, found 1 day ago
£433
Return
found 1 day ago
Select Alaska Airlines flight, departing Thu, 24 Sept from St. Louis to Denver, returning Mon, 28 Sept, priced at £433 found 1 day ago

Alternative airports near Denver

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

Select flight to Denver Intl. DEN. Cheapest option available. Average driving time to city centre is 32 minutes. Flights from £708
DEN
Denver Intl.
Cheapest
Average driving time to city centre32 min
Flights from £708

Frequently asked questions

How much does a flight from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Denver, CO (DEN-Denver Intl.) cost?
You can find one-way and return flights from STL to DEN with Expedia. Flight prices vary based on the month and day of the week you want to travel, as well as the airline and how far in advance you book your ticket. Filter your search on Expedia by "Price (lowest to highest)" to see our cheapest fares first, and use the Price Tracking tool to receive alerts when STL to DEN ticket fares go up or down.
What is the cheapest month to fly from St. Louis, MO (STL) to Denver, CO (DEN)?
The cheapest months to fly from St. Louis, MO (STL) to Denver, CO (DEN) are typically during off-peak season when demand is low. Traveling in off-peak or shoulder months is usually a good way to secure cheap tickets, just remember to avoid flying during holidays if you are able to. Use the calendar view in your search to see which months have low fares on this route.
Which airlines fly direct from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Denver, CO (DEN-Denver Intl.)?
There are 3 airlines offering direct flights from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Denver, CO (DEN-Denver Intl.). These include:
  • Southwest Airlines operates 47 direct flights from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Denver, CO (DEN-Denver Intl.) every week.
  • United operates 41 direct flights from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Denver, CO (DEN-Denver Intl.) every week.
  • Frontier Airlines operates 7 direct flights from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Denver, CO (DEN-Denver Intl.) every week.
How do I find cheap flights from St. Louis, MO (STL) to Denver, CO (DEN)?
To find a cheap flight from St. Louis, MO (STL) to Denver, CO (DEN), be flexible with your dates. Traveling outside of peak vacation months and booking a mid-week flight can help you save. Early morning and late night flights are often more affordable, too. Expedia allows you to compare flight times, airlines and routes all in one place to find low fares. You can also set up Price Tracking and receive alerts when fares go up or down.
What is the best time to fly from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Denver, CO (DEN-Denver Intl.)?
The cheapest months to fly from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Denver, CO (DEN-Denver Intl.) are typically September and August, with average return flights around £204. However, the most popular months for this route are November and July, meaning you'll find plenty of flight options during those times. If you're looking for the best balance of good prices and a wide selection of flights, you might consider travelling in late summer or early fall.
What is the earliest flight from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Denver, CO (DEN-Denver Intl.)?
The earliest flight from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Denver, CO (DEN-Denver Intl.) typically departs around 5:00 AM. This service is operated by American Airlines. This is a seasonal service, active in January, November, and December. An early departure like this can help you make the most of your time at your destination. To compare early flights on Expedia, select the "Early Morning" and "Morning" filters in your search.
How long does it take to fly from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Denver, CO (DEN-Denver Intl.)?
A direct flight from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Denver, CO (DEN-Denver Intl.) typically takes around 2 hours 30 minutes. This route covers a distance of approximately 1,236 kilometers. If you opt for a one-stop flight, your journey will usually take longer, around 6 hours. Flights with two or more stops will extend your travel time even further, to about 9 hours 50 minutes. Keep in mind that actual flight times can vary due to factors like wind patterns and air traffic, so it's always a good idea to allow for some flexibility in your travel plans.
Can you fly business or first class from St. Louis, MO (STL) to Denver, CO (DEN)?
Select the "Business class" and "First class" filters when looking for St. Louis, MO (STL) to Denver, CO (DEN) flights on Expedia. This is the easiest way to compare prices, routes and flight times for your trip.
How do I earn miles on a St. Louis, MO (STL-Lambert-St. Louis Intl.) to Denver, CO (DEN-Denver Intl.) flight with Expedia?
It's easy to earn miles on a St. Louis, MO (STL-Lambert-St. Louis Intl.) to Denver, CO (DEN-Denver Intl.) flight when you book with Expedia. Before you confirm your booking, simply select your frequent flyer program and enter your program number. As a member of One Key™, you can also earn OneKeyCash™* on top of your airline miles when you book with Expedia.*Excludes taxes and fees. OneKeyCash is not redeemable for cash and can only be used on Expedia and other participating brands.
What airports do you fly into for Denver, CO (DEN) from St. Louis, MO (STL)?
If you're planning to travel to Denver from Lambert-St. Louis Intl. (STL), you can fly directly into Denver Intl. (DEN). Some flights may connect through major hubs like Seattle - Tacoma Intl. (SEA), Love Field (DAL), or Midway Intl. (MDW) before reaching Denver. Compare routes and airports on Expedia to find the best flight options for your travel plans.
Is it cheaper to buy a plane ticket from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Denver, CO (DEN-Denver Intl.) at the last minute?
Typically, booking a last minute flight from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Denver, CO (DEN-Denver Intl.) will be more expensive than booking in advance. As the departure date approaches, there are usually fewer seats available which can drive up the cost. However, if there's some wiggle room with your travel dates and times, you could bag a cheap last-minute fare.
Is it cheaper to book a St. Louis, MO (STL-Lambert-St. Louis Intl.) to Denver, CO (DEN-Denver Intl.) flight and hotel package?
Securing a St. Louis, MO (STL-Lambert-St. Louis Intl.) to Denver, CO (DEN-Denver Intl.) flight and hotel package is usually cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your travels all in one place. Select from our extensive range of stays and then add flights, activities and car rentals to your booking. Bundle everything together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from St. Louis, MO (STL) to Denver, CO (DEN)?
If you booked your St. Louis, MO (STL) to Denver, CO (DEN) flight within the last 24 hours, you may be able to modify or cancel it without any fees. Depending on the airline and the type of ticket you have, additional charges may apply for changes beyond this timeframe. Airline policies and contact information can be found in your itinerary or confirmation email. Or, head to our Customer Service portal if you'd like more information.

Travel information

Origin airport
Lambert-St. Louis Intl.
Destination airport
Denver Intl.
Airlines serving
Alaska Airlines
Return price
£384
Distance
1228 km
Average flight time
1 hour 16 mins

Book with confidence

Compare flights from St. Louis to Denver easily and book with confidence

For travelling on business or for pleasure, Expedia makes it easy to book your flights from St. Louis to Denver. Operating between them flights per day, 20 airlines cover the route. And fly direct, getting you to Denver Intl. in just hours. If you have a preferred carrier, use our advanced search tool to find the right flight from Lambert-St. Louis Intl. to Denver Intl..  

To make things even better, in the advanced search, you can also choose to fly economy, premium economy, business or first class, select your maximum number of stops, and pick your preferred departure and arrival time. You can also opt for refundable and direct flights. 

Grab a great deal on your flight from Lambert-St. Louis Intl. (STL) to Denver Intl. (DEN)

The easiest way to view the best deals on flights from St. Louis to Denver today is to enter your travel dates and hit search. From here, you can sort your results by price to see the cheapest flights first. Right now, return flights from Lambert-St. Louis Intl. to Denver Intl. start at just £385 and range up to £433.  

To find an even better deal, try  

  • being flexible on your dates – midweek flights can be cheaper
  • looking for other airports near St. Louis and Denver
  • booking your flight during September, the cheapest month on this route
  • varying your flight times – early morning and late at night are sometimes cheaper 

Why you should book your St. Louis to Denver flight with Expedia!

We cater for all flight types, cabin classes and airlines. So whether you’re booking flights from Lambert-St. Louis Intl. to Denver Intl. for a budget break or a business trip with a bit of pleasure thrown in, we make it easy to secure the seat that’s right for you.  

Thanks to our supersized inventory that offers great choice all in one place, you know you’ll get a great deal with Expedia. Especially if you bundle your flight together with your hotel, you will unlock amazing savings. For added peace of mind, you can choose flexible bookings or filter to find refundable options, so you won’t pay a fee to change your flight.  

Compare flights from St. Louis to Denver easily and book with confidence

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*Available to Expedia members.