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

View AU$165 flight on Tue, 18 Aug 2026Opens in a new window

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

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

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.

Frequently asked questions

What is the cheapest month to fly from Denver, CO (DEN-Denver Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
September is typically the cheapest month to fly from Denver, CO (DEN-Denver Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.), with average round-trip fares around 667 CAD. This is about 15% lower than the average price throughout the year. September often sees lower prices as the summer travel rush ends and before the holiday season begins, leading to reduced demand. Other cheap months to fly from Denver, CO (DEN-Denver Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) include August and October.*Averages based on flights available on Expedia in the last year.
Which airlines fly direct from Denver, CO (DEN-Denver Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
Enter DEN to STL and your travel dates, then apply the 'Nonstop' filter to see only direct flights.
How do I find cheap flights from Denver, CO (DEN-Denver Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
To find a cheap flight from Denver, CO (DEN-Denver Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.), 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 airline to fly with from Denver, CO (DEN-Denver Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
The best airline to fly with from Denver, CO (DEN-Denver Intl.) (DEN) to St. Louis, MO (STL-Lambert-St. Louis Intl.) (STL) will differ from traveler to traveler. If you like to fly early, WN offers early morning flights. If price is the most important factor, F9 typically offers the lowest fares. WN offers the most daily flights from Denver, CO (DEN-Denver Intl.) (DEN) to St. Louis, MO (STL-Lambert-St. Louis Intl.) (STL), which is great if flexibility is what you value most. The best carrier for this journey could also be the one you have a loyalty membership with, as flying with that airline or another airline within the same alliance could help you collect points or enjoy lounge access.
What is the best time to fly from Denver, CO (DEN-Denver Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
The best time to fly from Denver, CO (DEN-Denver Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) is September. This month offers a great balance, as it's one of the cheapest times to fly, with average round-trip flights around 667 CAD, and it's also a popular month for travel, meaning you'll find plenty of flight options. August is also a cheap month to consider if you're looking for good value.*Prices based on flights available on Expedia in the last year.
How many flights per day from Denver, CO (DEN-Denver Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
There are approximately 12 nonstop flights per day from Denver Intl. (DEN) to Lambert-St. Louis Intl. (STL). For even more choice, look at flights that include layovers, as there are around 182 connecting flights per day. Some common connection points include O'Hare Intl. (ORD), Seattle - Tacoma Intl. (SEA), and Portland Intl. (PDX).
What is the earliest flight from Denver, CO (DEN-Denver Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
The earliest flight from Denver International Airport (DEN) to Lambert-St. Louis International Airport (STL) typically departs at approximately 12:00 AM local time, operated by Frontier Airlines. This is a seasonal service active in August, September, and October. An early departure like this can help you maximize your time at your destination. To compare early flights on Expedia, select the "Early Morning" and "Morning" filters in your search.
What day of the week has the most flights from Denver, CO (DEN-Denver Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
If you're flying from Denver International Airport (DEN) to Lambert-St. Louis International Airport (STL), you'll typically find the most flights on a Friday, with around 117 flights available. This gives you plenty of options to choose from for your journey. Major airlines on this route include Southwest Airlines, Delta Air Lines, and American Airlines. Friday offers notably more flight options compared to other days of the week, making it a great day to plan your travel.
What are the most popular departure times for flights from Denver, CO (DEN-Denver Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
The most popular departure times for flights from Denver International Airport (DEN) to Lambert-St. Louis International Airport (STL) are in the early morning, from 6am to 9am. About 24% of passengers prefer this time window. Many major carriers, including Southwest Airlines and American Airlines, offer flights during this window. Many travelers prefer these early morning flights to get a head start on their day at their destination.
How long does it take to fly from Denver, CO (DEN-Denver Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
Flying nonstop from DEN to STL takes around 2 hours, with the route covering approximately 768 miles. Flights with a layover typically take 3 hours 50 minutes longer than direct options. Keep in mind that actual flight times can vary due to wind patterns, weather, and air traffic.
Can you fly business or first class from Denver, CO (DEN-Denver Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
Select the "Business class" and "First class" filters when looking for DEN to STL 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 Denver, CO (DEN-Denver Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) flight with Expedia?
It's easy to earn miles on a Denver, CO (DEN-Denver Intl.) to St. Louis, MO (STL-Lambert-St. Louis 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 St. Louis from Denver Intl. (DEN)?
If you're planning to travel to St. Louis from Denver Intl. (DEN), you can fly into Lambert-St. Louis Intl. (STL) Some flights may connect through major hubs like Portland Intl. (PDX), Love Field (DAL), Tulsa Intl. (TUL) before reaching St. Louis. 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 Denver, CO (DEN-Denver Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) at the last minute?
Typically, booking a last minute flight from Denver, CO (DEN-Denver Intl.) to St. Louis, MO (STL-Lambert-St. Louis 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 Denver, CO (DEN-Denver Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) flight and hotel package?
Securing a Denver, CO (DEN-Denver Intl.) to St. Louis, MO (STL-Lambert-St. Louis 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 Denver, CO (DEN-Denver Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
If you booked your Denver, CO (DEN-Denver Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) 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
Denver Intl.
Destination airport
Lambert-St. Louis Intl.
Distance
1228 km
Average flight time
3 hours 4 mins

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Your quick guide to flights from Denver to St. Louis

Pick up great flights from Denver to St. Louis

With Expedia, you have your pick of flights a day with 20 airlines covering flights from Denver to St. Louis. Whether you’re on a business trip, a family holiday or a luxury break, just enter your travel dates, hit search then check out your choice of flights. Select from return, one way or multi-city flights, and use the advance search tool if you want a direct or refundable flight. You can narrow your search to show you just your preferred cabin class and airline, too. It’s all easy. You can book direct flights from Denver to St. Louis that take around hours.

Find cheap flights from Denver to St. Louis

From the great flight deals with prices currently ranging from to , you can choose to see the cheapest flights first. Generally, you can book the cheapest flights from Denver to St. Louis around 4 to 6 weeks in advance. If your travel dates are flexible, try to avoid weekends and peak seasons – when you are more likely to grab the lowest prices. Even last minute, there are some impressive deals. The cheapest time to fly to St. Louis is normally in .

Reasons to book your flight from Denver to St. Louis with Expedia

Expedia makes it easy to find, book, and travel, with everything you need all in one place. When you enter your travel details, find fantastic deals just for you on flight tickets from Denver to St. Louis across all the main airline carriers, so you can save time, dollars, and hassle finding the perfect flight. If you think your plans could change, choose refundable flights so any changes won’t cost you more. Book your flight to St. Louis right now and, if you join Expedia Rewards, you earn points this time and every time you travel with Expedia.

Your quick guide to flights from Denver to St. Louis

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