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

    notification illustration

    Be in the know

    Get alerts if flight prices drop or rise*
    deals illustration

    Book smarter

    Save up to 30% on select hotels after you book a flight*
    trophy illustration

    Earn twice

    Earn your airline miles on top of our OneKeyCash
    Learn about One Key

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

Prices were available within the past 7 days and start at $29 for one-way flights and $54 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Frontier Airlines
Wed, Jan 21 - Fri, Jan 23
DEN
Denver
STL
St. Louis
$54 Roundtrip, just found
$54
Roundtrip
just found
Select Frontier Airlines flight, departing Wed, Jan 21 from Denver to St. Louis, returning Fri, Jan 23, priced at $54 just found
Frontier Airlines
Mon, Jan 26 - Wed, Jan 28
DEN
Denver
STL
St. Louis
$64 Roundtrip, just found
$64
Roundtrip
just found
Select Frontier Airlines flight, departing Mon, Jan 26 from Denver to St. Louis, returning Wed, Jan 28, priced at $64 just found
Frontier Airlines
Sat, Dec 13 - Mon, Dec 22
DEN
Denver
STL
St. Louis
$74 Roundtrip, found 9 hours ago
$74
Roundtrip
found 9 hours ago
Select Frontier Airlines flight, departing Sat, Dec 13 from Denver to St. Louis, returning Mon, Dec 22, priced at $74 found 9 hours ago
Frontier Airlines
Sat, Dec 13 - Sat, Dec 20
DEN
Denver
STL
St. Louis
$79 Roundtrip, found 5 hours ago
$79
Roundtrip
found 5 hours ago
Select Frontier Airlines flight, departing Sat, Dec 13 from Denver to St. Louis, returning Sat, Dec 20, priced at $79 found 5 hours ago
Frontier Airlines
Sat, Dec 13 - Mon, Dec 15
DEN
Denver
STL
St. Louis
$82 Roundtrip, just found
$82
Roundtrip
just found
Select Frontier Airlines flight, departing Sat, Dec 13 from Denver to St. Louis, returning Mon, Dec 15, priced at $82 just found
Frontier Airlines
Sat, Dec 13 - Mon, Dec 22
DEN
Denver
STL
St. Louis
$84 Roundtrip, found 9 hours ago
$84
Roundtrip
found 9 hours ago
Select Frontier Airlines flight, departing Sat, Dec 13 from Denver to St. Louis, returning Mon, Dec 22, priced at $84 found 9 hours ago
United
Wed, Jan 21 - Sat, Jan 31
DEN
Denver
STL
St. Louis
$157 Roundtrip, found 7 hours ago
$157
Roundtrip
found 7 hours ago
Select United flight, departing Wed, Jan 21 from Denver to St. Louis, returning Sat, Jan 31, priced at $157 found 7 hours ago
Southwest Airlines
Sat, Dec 13 - Wed, Dec 17
DEN
Denver
STL
St. Louis
$157 Roundtrip, just found
$157
Roundtrip
just found
Select Southwest Airlines flight, departing Sat, Dec 13 from Denver to St. Louis, returning Wed, Dec 17, priced at $157 just found
American Airlines
Sat, Dec 13 - Wed, Dec 17
DEN
Denver
STL
St. Louis
$187 Roundtrip, just found
$187
Roundtrip
just found
Select American Airlines flight, departing Sat, Dec 13 from Denver to St. Louis, returning Wed, Dec 17, priced at $187 just found
Alaska Airlines
Fri, Dec 5 - Wed, Dec 10
DEN
Denver
STL
St. Louis
$294 Roundtrip, found 17 hours ago
$294
Roundtrip
found 17 hours ago
Select Alaska Airlines flight, departing Fri, Dec 5 from Denver to St. Louis, returning Wed, Dec 10, priced at $294 found 17 hours ago

Find the cheapest month to fly from Denver (DEN) to St. Louis (STL)

February is typically the cheapest month to fly

From $58 - $284 per traveler.

Alternative airports near St. Louis

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

Select flight to Lambert-St. Louis Intl. STL. Cheapest option available. Average driving time to city center is 20 minutes. Flights from $116
STL
Lambert-St. Louis Intl.
Cheapest
Average driving time to city center20 min
Flights from $116

Frequently asked questions

How much does a flight from Denver Intl. Airport (DEN) to Lambert-St. Louis Intl. Airport (STL) cost?
Snag a cheap one-way flight from $29 or cheap return flight from $54 from Denver Intl. Airport (DEN) to Lambert-St. Louis Intl. Airport (STL) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to find our cheapest flight deals on this route.
What is the cheapest month to fly from Denver Intl. Airport (DEN) to Lambert-St. Louis Intl. Airport (STL)?
Traveling in January is a great way to save, as it's the cheapest month for flights between DEN and STL. You'll usually find the lowest fares during off-peak months.
Which airlines fly direct from Denver Intl. Airport (DEN) to Lambert-St. Louis Intl. Airport (STL)?
You can choose from 3 airlines that fly directly from Denver Intl. Airport (DEN) to Lambert-St. Louis Intl. Airport (STL). These include:

  • Southwest Airlines
  • United Airlines
  • Frontier Airlines

What is the cheapest airline that flies from Denver Intl. Airport (DEN) to Lambert-St. Louis Intl. Airport (STL)?
The cheapest airline to offer flights between Denver Intl. Airport (DEN) and Lambert-St. Louis Intl. Airport (STL) can vary based on your travel dates. Frontier Airlines and United Airlines are just some of the choices offering reasonable prices. Use Expedia's filters to compare airlines in one place and find the right DEN to STL flight that fits your budget.
How many flights per day from Denver Intl. Airport (DEN) to Lambert-St. Louis Intl. Airport (STL)?
With, on average, 8 direct flights that operate from Denver Intl. Airport (DEN) to Lambert-St. Louis Intl. Airport (STL) daily, you'll be cruising above the clouds before you know it.
What are the most popular departure times for flights from Denver Intl. Airport (DEN) to Lambert-St. Louis Intl. Airport (STL)?
Flights between DEN and STL are busiest at 9 AM. If you're after a more relaxed trip and potentially cheaper prices, choose a departure outside the usual busy windows.
What day of the week has the most flights from DEN to STL?
If you depart on a Monday, you'll get the largest range of choices for flights from Denver Intl. Airport (DEN) to Lambert-St. Louis Intl. Airport (STL).
What is the earliest flight from Denver Intl. Airport (DEN) to Lambert-St. Louis Intl. Airport (STL)?
The earliest flight taking off from Denver Intl. Airport (DEN) is at around 6:00AM UTC-7. Catch this flight and you'll touch down at Lambert-St. Louis Intl. Airport (STL) at approximately 9:16AM UTC-6. The total travel time is 2h 16m.
How long does it take to fly from Denver Intl. Airport (DEN) to Lambert-St. Louis Intl. Airport (STL)?
Flights from DEN to STL have an average travel time of 2 hours and 5 minutes. The distance between the two is 770 mi.
What airline has the least delays from DEN to STL?
Frontier Airlines has the best track record for on-time direct flights from Denver Intl. Airport (DEN) to Lambert-St. Louis Intl. Airport (STL), with an on-time score of 80%. Use the Expedia App to view your flight status before you leave and receive notifications about any trip changes.
What is the best time to fly from Denver Intl. Airport (DEN) to Lambert-St. Louis Intl. Airport (STL)?
To land at Lambert-St. Louis Intl. Airport (STL) on schedule, opt for a flight that leaves from Denver Intl. Airport (DEN) before 3 PM. The chance of cancellations is 22% higher, on average, for departures after this time.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
What airports do you fly into for St. Louis from Denver Intl. Airport (DEN)?
If you've booked a direct flight from Denver Intl. Airport (DEN) to St. Louis, Lambert-St. Louis Intl. Airport (STL) is the only airport you can touch down at.
Is it cheaper to buy a plane ticket from Denver Intl. Airport (DEN) to Lambert-St. Louis Intl. Airport (STL) last-minute?
Booking your ticket from DEN to STL right before your journey is typically more expensive. However, if you're flexible with your travel times and dates, you could score a cheap last-minute fare.
Is it cheaper to book a DEN to STL flight and hotel package?
Securing a DEN to STL flight and hotel package is typically cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your travels all in one place. Choose from our wide range of hotels and then add flights, car rentals and activities 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 Intl. Airport (DEN) to Lambert-St. Louis Intl. Airport (STL)?
You can usually reschedule or cancel your DEN to STL flight. However, if it's been more than 24 hours since booking, additional charges may apply. Check your airline's policies in your itinerary to see what changes are allowed and whether any costs are involved. You'll also find more details on our Customer Service portal.

Travel information

0
Origin airport
Denver Intl.
Destination airport
Lambert-St. Louis Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, Southwest Airlines, United
Roundtrip price
$54
Distance
767 mi

Book with confidence

Denver to St. Louis Flights

The cheapest times to fly from Denver to St. Louis

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from Denver to St. Louis are during the month of January. You can find some of the cheapest flights from Denver to St. Louis with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Denver to St. Louis

Sunday is one of the best days to book for cheap flights from Denver to St. Louis: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from Denver to St. Louis

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from Denver to St. Louis in 2025. You can also book with separate airlines for your outbound and return journeys, from $29 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap Denver to St. Louis flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your Denver to St. Louis airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

Denver to St. Louis Flights

Explore a world of travel with Expedia

*Available to One Key members.