$71 Find Cheap Flights from Denver to St. Charles

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Denver to St. Charles departing on 10/8. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy

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

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Denver to St. Charles that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Denver to St. Charles

Tue, Sep 2 - Thu, Sep 11
Frontier Logo
6:00 am - 9:11 amDEN-STL
2h 11mnonstop
Frontier Logo
7:52 pm - 9:20 pmSTL-DEN
2h 28mnonstop
$116Frontier
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Mon, Aug 11 - Sat, Aug 16
Frontier Logo
6:00 am - 9:11 amDEN-STL
2h 11mnonstop
Frontier Logo
7:29 pm - 8:58 pmSTL-DEN
2h 29mnonstop
$117Frontier
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Mon, Aug 11 - Sat, Aug 16
Southwest Logo
7:10 am - 1:45 pmDEN-STL
5h 35m1 stop
Southwest Logo
5:55 pm - 7:15 pmSTL-DEN
2h 20mnonstop
$167Southwest
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Wed, Sep 24 - Mon, Sep 29
American Airlines Logo
12:41 pm - 8:15 pmDEN-STL
6h 34m1 stop
American Airlines Logo
3:57 pm - 9:01 pmSTL-DEN
6h 04m1 stop
$177American Airlines
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Thu, Oct 2 - Sat, Oct 4
American Airlines Logo
2:17 pm - 8:25 pmDEN-STL
5h 08m1 stop
American Airlines Logo
9:56 am - 4:41 pmSTL-DEN
7h 45m1 stop
$182American Airlines
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Fri, Sep 12 - Wed, Sep 17
Delta Logo
12:55 am - 9:35 amDEN-STL
7h 40m1 stop
Delta Logo
2:15 pm - 7:10 pmSTL-DEN
5h 55m1 stop
$197Delta
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Thu, Sep 11 - Wed, Sep 17
Delta Logo
12:55 am - 9:35 amDEN-STL
7h 40m1 stop
Delta Logo
7:30 am - 3:09 pmSTL-DEN
8h 39m1 stop
$207Delta
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Sat, Jul 12 - Mon, Jul 14
Southwest Logo
5:25 am - 8:25 amDEN-STL
2h 00mnonstop
Southwest Logo
5:05 am - 8:30 amSTL-DEN
4h 25m1 stop
$227Southwest
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Tue, Sep 16 - Sat, Sep 20
United Airlines Logo
1:26 pm - 4:33 pmDEN-STL
2h 07mnonstop
United Airlines Logo
3:20 pm - 8:12 pmSTL-DEN
5h 52m1 stop
$274United Airlines
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Tue, Jul 8 - Tue, Jul 15
United Airlines Logo
8:40 pm - 11:59 pmDEN-STL
2h 19mnonstop
United Airlines Logo
5:15 am - 6:52 amSTL-DEN
2h 37mnonstop
$279United Airlines
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Good to know

Low seasonJanuary
High seasonJuly
Cheapest flight$71
Best time to beat the crowds with an average 22% drop in price.
Most popular time to fly and prices are also 15% lower on average.
Flight from Denver to St. Louis

When to book flights from Denver to St. Charles

Are your dates flexible? Find out the best times to travel from Denver to St. Charles based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price

FAQs for booking flights from Denver to St. Charles

  • Which airports will I be using when flying from Denver to St. Charles?

    When flying out of Denver you’ll be using Denver Intl. St. Charles does not have its own airport so you’ll be flying into nearby Lambert-St Louis airport, which is 7.2 mi away.

  • How long does a flight from Denver to St. Charles take?

    Direct flights cover the 767 miles separating Denver and St. Charles in about 2h 00m.

  • How many flights are there between Denver and St. Charles?

    15 direct flights run between Denver and St. Charles on a daily basis. On average, there are about 108 departures each week.

  • What’s the cheapest day of the week to fly between Denver and St. Charles?

    Consider leaving on a Tuesday and avoid Mondays if you are looking for the best rates. For your return to Denver, you’ll find the best rates on Thursdays and the most expensive ones on Sundays.

  • How does KAYAK find such low prices on flights from Denver to St. Charles?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Denver to St. Charles.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Denver to St. Charles?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to St. Charles from Denver is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Denver to St. Charles?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to St. Charles with an airline and back to Denver with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Denver to St. Charles?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to St. Charles from Denver up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

  • Which airlines provide the cheapest flights from Denver to St. Charles?

    In the last 72 hours, the cheapest one-way ticket between Denver and St. Charles found on KAYAK was with Frontier for $71. Frontier offered a round-trip connection from $116 and Southwest from $167.

Top tips for finding cheap flights from Denver to St. Charles

  • There is no airport in St. Charles. Instead, you’ll be flying into St. Louis Lambert Airport when flying between Denver and St. Charles.
  • The cheapest flight from Denver to St. Charles was found 74 days before departure, on average.
  • Book at least 1 week before departure in order to get a below-average price.
  • High season is considered to be May, June and July. The cheapest month to fly is January.

Top 3 airlines serving Denver to St. Charles

 
Need help choosing which airline to fly with from Denver to St. Charles? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
8.0
SouthwestOverall score based on 4287 reviews
8.2Boarding
7.1Food
8.6Crew
8.0Comfort
7.6Entertainment
Airline reviews

Flight crew and cabin crew were great. I had to rearrange flights because my original flight was 3hrs delayed for weather, the rub is the flight I moved to boarded on time then we sat at the gate for 2 hours because scheduling stole our first officer for another flight, TWICE. Then our actual FO was an hour delayed. To make it worse my original flight went from a 3 hour delay to departing 15min EARLY. Just poor scheduling operations all around.

6.0 GoodAnonymous, May 2025HOU - MCI
Read more Southwest reviews

Flight crew and cabin crew were great. I had to rearrange flights because my original flight was 3hrs delayed for weather, the rub is the flight I moved to boarded on time then we sat at the gate for 2 hours because scheduling stole our first officer for another flight, TWICE. Then our actual FO was an hour delayed. To make it worse my original flight went from a 3 hour delay to departing 15min EARLY. Just poor scheduling operations all around.

I would have liked to arrive on time - not 5 hours late!

1.5 hour delay, poor service, no compassion from the crew. Terrible experience

Our flight was diverted from being a non-stop to getting within 150 miles and requiring another plane. We heard 4 or 5 different versions from SW as to why we had to stop, then wait for a replacement plane. Five hour delay, weather did not come up as a single excuse.... communication was not clear and well explained. No one really took charge!

I really like open seating. I hate that I've heard this is going away. This is one of the unique things that makes Southwest my goto choice.

It was 2 hours 45 minutes late, for no apparently clear reason.

Crew was great flight was great baggage claim was a failure. It took over 1 hour for bags to arrive. Poor communication poor effort when I spoke to the supervisor about the delay

Everything was great except the food. The pretzels are really crappy.

It seems as though the provisions are even less. Although SWA used to be an economy Airline, that isn't really the case anymore. I paid over $700. for a round trip to Denver and I could have flown just about any airline for the price. The drinks are now in a 6-ounce cup and with ice I'm sure a can would fill more than 2 cups. However, I am very proud of SWA for using paper rather than continuing to contribute to the millions of plastic cups being used each day. I've thought of this fr many years and am so glad to see it come to fruition, if not by only SWA so far.

My original flight was extremely delayed but I was able to join the standby list for an earlier flight. I was grateful for this feature but I wish I could’ve gotten my standby confirmation sooner.

Impressed with the service despite turbulence because of the weather. Both flights arrived before their scheduled times.

Great experience…left a bit behind schedule but made up fir that in the air and landed 10 minutes early 😁

Electric plugs didn't work. Entertainment system wasn't working

The design of the light switch on the arm rest is ridiculous.

The gate attendant let me walk right by her with a bag too big for the overhead compartment

Overall, it was a good experience. Boarding was good and there was plenty of overhead bin space for everyone’s carryons (even when we boarded toward the end). Only improvement would be to offer trash service more regularly.

David went above and beyond to make our flight the best that it could be

No food service almost missed because of first flight delays

Had a hard time finding my assigned seat. No attendants to assist.

The negative was the wait at the airport coming back. I checked my bags in, an hour before boarding and I get the notification that my flight was delayed. Rather had gotten the notification while I was at the hotel. Then it was delayed 3 x’s. Ugh!

I never got to experience the flight because they delayed my first flight and I missed this one. Then Frontier didn't want to help me rebook a flight to get me to my final destination.

The Boarding process in Denver was chaotic, and since the line was so long, we were lined up very far from the gate. If there were any announcements from the gate staff, we didn't hear them. The flight attendants were spectacular. The only negative part of the flight was sitting by a 2 1/2 year old who was unruly and unfortunately had parents that matched his behaviors. Also, the restaurants in Denver on the E concourse, they didn't have food (passengers could only order 1 item on the entire menu) or the restaurants had 12-14 people waiting for orders to be prepared and another 6 people waiting to order. If you have a layover in Denver and need to grab food, be prepared to visit the shops with pre-packaged sandwiches, or you can visit another concourse but it may take a while to transit throughout the airport.

Everything went as planned. Crew was great. Seats were still not that comfortable.

they delayed my flight which ended up, causing my layover flight to leave without me, resulting in me missing a flight and having to stay overnight in Houston international. I got no compensation other than a flight to my original location only a day later. i’ve never experienced such a unprofessional situation

The seats were extremely hard and uncomfortable, even for a budget airline.

Boarding was very well executed. Got my bag right away.

Overall experience good. There was no food and seats were not terribly comfortable.

There was nothing to like, flight delayed had to move to different departure areas, disorganized to say the leasr

There were a lot of issues every step of the process. Check in, security, boarding, and dealing with luggage. Plus the money you think you are saving you end up using in hidden fees.

The flight attendant was arguing with a passenger before takeoff. The passenger was frustrated but the flight attendant should have handled it with grace, but instead she was nasty and rude. The seats were comfortable and the flight was uneventful. I wish we didn’t have to pay for drinks or snacks but that’s what you get with a budget airline.

Everything you need to know for your flight from Denver to St. Charles

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