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

Popular airlines from Denver Intl. Airport (DEN) to St. Louis, MO (SUS-Spirit of St. Louis)

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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 $175
STL
Lambert-St. Louis Intl.
Cheapest
Average driving time to city center20 min
Flights from $175
Flights from Denver (DEN) to St. Louis (SUS)
Origin airport
Denver Intl.
Destination airport
Spirit of St. Louis
Distance
754 mi

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 . 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 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.

 

Frequently asked questions

How much does a flight from Denver Intl. Airport (DEN) to Spirit of St. Louis Airport (SUS) cost?
Secure a cheap one-way flight or cheap return flight from Denver Intl. Airport (DEN) to Spirit of St. Louis Airport (SUS) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to see our cheapest flight offers on this route.
What is the cheapest month to fly from Denver Intl. Airport (DEN) to Spirit of St. Louis Airport (SUS)?
The cheapest month to fly from DEN to SUS is , when there's less demand. Off-peak months are usually when you'll find lower airfares between these airports.
What is the cheapest airline that flies from Denver Intl. Airport (DEN) to Spirit of St. Louis Airport (SUS)?
Use the filter tool on Expedia to compare airlines and find the cheapest carrier that'll take you from DEN to SUS. Then, sort your results by "Price (lowest to highest)" to pick up the best deal available.
How many flights per day from Denver Intl. Airport (DEN) to Spirit of St. Louis Airport (SUS)?
Nonstop flights from Denver Intl. Airport (DEN) to Spirit of St. Louis Airport (SUS) aren't available daily, so you'll have to take a flight with a layover. Explore your options with Expedia's filters. Enter your travel dates and click on either "1 Stop" or "2+ Stops."
What day of the week has the most flights from DEN to SUS?
Friday is usually the busiest day for flights, while Tuesday is often the quietest.* Just remember that flight schedules can change depending on various factors, including the carrier and season.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Denver Intl. Airport (DEN) to Spirit of St. Louis Airport (SUS)?
To touch down at Spirit of St. Louis Airport (SUS) on schedule, select a flight that leaves 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)?
Explore your flight options from Denver Intl. Airport (DEN) to Lambert-St. Louis Intl. Airport (STL). This is the only airport in St. Louis you can touch down at if you're taking a direct flight.
Is it cheaper to buy a plane ticket from Denver Intl. Airport (DEN) to Spirit of St. Louis Airport (SUS) last-minute?
Booking your ticket from DEN to SUS right before your trip is usually more expensive. But if there's some wiggle room with your departure times and dates, you could score a cheap last-minute fare.
Is it cheaper to book a DEN to SUS flight and hotel package?
Compared with arranging flights and hotels separately, booking a DEN to SUS flight and hotel package with Expedia could lead to significant savings. Better yet, having everything in one easy place takes the hassle out of planning your trip. Just secure your flights and select from our wide range of hotels, then tailor your trip with extras like tours, activities and car rentals.
Can I cancel or change the date of my flight from Denver Intl. Airport (DEN) to Spirit of St. Louis Airport (SUS)?
In most instances, you can modify or cancel your DEN to SUS flight. However, there may be additional fees, especially if you booked more than 24 hours ago. Double-check your itinerary for the airline's fees and policies on flight changes, or if you want more information, head to our Customer Service portal.

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