$30 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 11/1. 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

Sat, Oct 4 - Tue, Oct 7
Frontier Logo
6:00 am - 9:06 amDEN-STL
2h 06mnonstop
Frontier Logo
7:52 pm - 9:20 pmSTL-DEN
2h 28mnonstop
$54Frontier
Find Deal
Tue, Sep 2 - Tue, Sep 2
Frontier Logo
6:00 am - 9:11 amDEN-STL
2h 11mnonstop
Frontier Logo
7:54 pm - 9:23 pmSTL-DEN
2h 29mnonstop
$93Frontier
Find Deal
Tue, Aug 26 - Tue, Sep 2
Frontier Logo
6:00 am - 9:11 amDEN-STL
2h 11mnonstop
Frontier Logo
7:54 pm - 9:23 pmSTL-DEN
2h 29mnonstop
$99Frontier
Find Deal
Sat, Aug 30 - Tue, Sep 2
Frontier Logo
6:00 am - 9:11 amDEN-STL
2h 11mnonstop
Frontier Logo
7:54 pm - 9:23 pmSTL-DEN
2h 29mnonstop
$100Frontier
Find Deal
Tue, Oct 14 - Tue, Oct 21
Frontier Logo
6:00 am - 9:07 amDEN-STL
2h 07mnonstop
Frontier Logo
7:52 pm - 9:20 pmSTL-DEN
2h 28mnonstop
$101Frontier
Find Deal
Thu, Aug 28 - Thu, Sep 4
Frontier Logo
6:00 am - 9:11 amDEN-STL
2h 11mnonstop
Frontier Logo
7:55 pm - 9:20 pmSTL-DEN
2h 25mnonstop
$102Frontier
Find Deal
Tue, Aug 19 - Tue, Aug 19
Frontier Logo
6:00 am - 9:11 amDEN-STL
2h 11mnonstop
Frontier Logo
7:54 pm - 9:23 pmSTL-DEN
2h 29mnonstop
$104Frontier
Find Deal
Tue, Sep 2 - Thu, Sep 11
Frontier Logo
6:00 am - 9:11 amDEN-STL
2h 11mnonstop
Frontier Logo
7:55 pm - 9:20 pmSTL-DEN
2h 25mnonstop
$107Frontier
Find Deal
Fri, Sep 12 - Sun, Sep 14
Frontier Logo
6:00 am - 9:06 amDEN-STL
2h 06mnonstop
Frontier Logo
7:55 pm - 9:20 pmSTL-DEN
2h 25mnonstop
$110Frontier
Find Deal
Fri, Sep 26 - Tue, Sep 30
Frontier Logo
6:00 am - 9:06 amDEN-STL
2h 06mnonstop
Frontier Logo
7:55 pm - 9:20 pmSTL-DEN
2h 25mnonstop
$111Frontier
Find Deal
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Good to know

Low seasonJanuary
Cheapest flight$30
Best time to beat the crowds with an average 24% 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 06m.

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

    16 direct flights run between Denver and St. Charles on a daily basis. On average, there are about 112 departures each week.

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

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

  • 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.

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.

Reviews of the 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 4241 reviews
8.0Comfort
8.6Crew
8.1Boarding
7.0Food
7.5Entertainment
Airline reviews

southwest just starting charging for luggage. hadnt realized it until it was too late. now out $70 when i couldve bought a carry on if i wouldve known. free bags was one of the only reasons i chose southwest over another airline (the other being no assigned seats, which is apparently also being changed). stupid business decision. wont be flying southwest anymore.

2.0 MediocreAnonymous, Jul 2025AUS - RDU
Read more Southwest reviews

southwest just starting charging for luggage. hadnt realized it until it was too late. now out $70 when i couldve bought a carry on if i wouldve known. free bags was one of the only reasons i chose southwest over another airline (the other being no assigned seats, which is apparently also being changed). stupid business decision. wont be flying southwest anymore.

The quality of Southwest Airlines continues to degrade each time I fly with them. If it were not for the free luggage, I would probably choose another airline. Their prices are a little bit competitive, but way too high for the quality of the service. Southwest is not unique in this way. Domestic flight in the United States of America has continued to be a lower and lower quality product. Very sad when you compare the quality of domestic airlines to that of many international airlines around the world.

Very smooth checking in our luggage with a super pleasant SW agent. I enjoyed a fun entertaining movie.

WiFi did not work. For as outrageous as these flights cost, when they’re advertised with certain services/ features they should be in working order

It was one and half hour late... Not sure if any other experience matters.

For my birthday trip this was my second time ever flying, this trip was the best.

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!

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’m not gonna fly Frontier Airlines because booking is not an option. No water or food is for high price, not equipped for health emergency incompetent crew for emergency services. Cheap airline shows it is cheaper in all service categories. Boarding is the best of all airlines!

Very bad! No good service delayed my second connection flight

Frontier is terrible. Paid for exit row, not given exit row, refused to refund fee.

2 hour delay due to late plane, wrong size plane causing overbooking, and people getting off and on the plane after boarding was completed.

The worst. We never made our connection and they did absolutely nothing to help us at the airport.

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.

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

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