HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
St. Charles

$42+ Cheap flights from Denver (DEN) to St. Charles, MO

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 12/20. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — STL
Nov 29 — Dec 61
Sat 11/29
Sat 12/6
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Denver to St. Charles with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

Cheapflights Tip: The best prices from Denver Intl to St. Charles are usually found in January or August, booked 74 days in advance, depart on a Friday or Wednesday and return on a Wednesday

Find flight deals from Denver to St. Charles

Cheapest flights from Denver to St. Charles
Explore the most affordable flight options available from Denver to St. Charles. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 30, 2025.

This Kiwi.com deal was found by Cheapflights users on 10/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/126:00 amDEN - STL
Nonstop2h 07mFrontier
Sat 11/157:45 pmSTL - DEN
Nonstop2h 28mFrontier
Deal found 10/29$101
This Gotogate deal was found by Cheapflights users on 10/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/67:05 amDEN - STL
Nonstop2h 09mFrontier
Mon 12/83:30 pmSTL - DEN
1 stop29h 43mFrontier
Deal found 10/28$103
This CheapOair deal was found by Cheapflights users on 10/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/137:05 amDEN - STL
Nonstop2h 09mFrontier
Sat 1/37:43 pmSTL - DEN
Nonstop2h 32mFrontier
Deal found 10/29$107
This Priceline deal was found by Cheapflights users on 10/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/138:40 amDEN - STL
1 stop7h 47mFrontier
Mon 11/179:07 pmSTL - DEN
1 stop7h 52mFrontier
Deal found 10/29$110
This Frontier deal was found by Cheapflights users on 10/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/176:00 amDEN - STL
Nonstop2h 07mFrontier
Wed 11/197:45 pmSTL - DEN
Nonstop2h 28mFrontier
Deal found 10/30$111
This Frontier deal was found by Cheapflights users on 10/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/116:00 amDEN - STL
Nonstop2h 07mFrontier
Sun 11/167:45 pmSTL - DEN
Nonstop2h 28mFrontier
Deal found 10/28$112
This CheapOair deal was found by Cheapflights users on 10/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/107:05 amDEN - STL
Nonstop2h 09mFrontier
Sun 12/141:16 pmSTL - DEN
1 stop15h 42mFrontier
Deal found 10/28$115
This CheapOair deal was found by Cheapflights users on 10/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/57:05 amDEN - STL
Nonstop2h 09mFrontier
Mon 12/812:07 pmSTL - DEN
1 stop7h 01mFrontier
Deal found 10/28$116
This Frontier deal was found by Cheapflights users on 10/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/812:59 amDEN - STL
1 stop8h 13mFrontier
Tue 11/187:45 pmSTL - DEN
Nonstop2h 28mFrontier
Deal found 10/28$119
This Kiwi.com deal was found by Cheapflights users on 10/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/126:00 amDEN - STL
Nonstop2h 07mFrontier
Sun 11/167:45 pmSTL - DEN
Nonstop2h 28mFrontier
Deal found 10/28$120

Cheap flight deals from Denver to St. Charles

Keep the following information in mind while searching for Denver to St. Charles flight deals. Data was last updated October 30, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$101
(Kiwi.com)

One-way from

$42
(Mytrip)

Popular in

June

Cheapest in

January

Average price

$217
Provider with most accurate pricing for Denver Intl-Lambert-St Louis flight deals.
Search Deals
Provider most trusted by Cheapflights users for Denver Intl-Lambert-St Louis flights.
Search Deals
From Denver Intl to St. Charles
Search Deals
One-way flight from Denver Intl to St. Charles
Search Deals
Highest demand for flights based on searches. 10% potential increase in price ($28 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($6 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in October 2025
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Denver to St. Charles that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated October 30, 2025.
Use the filters below to find and compare flights from Denver to St. Charles that are best for you.

Fly from

Denver

Fly to

St. Charles

Route

Depart

Return

Price

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Thu 12/11

12:59 am-9:47 am

1 stop7h 48m

Lambert-St Louis

Sun 12/14

1:16 pm-3:58 am

1 stop15h 42m

$176

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Sat 12/6

5:00 am-8:05 am

Nonstop2h 05m

Lambert-St Louis

Mon 12/8

5:35 am-7:00 am

Nonstop2h 25m

$197

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Fri 12/5

12:50 am-10:24 am

1 stop8h 34m

Lambert-St Louis

Mon 12/8

9:30 am-3:10 pm

1 stop6h 40m

$217

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Fri 12/5

8:15 am-11:20 am

Nonstop2h 05m

Lambert-St Louis

Sun 12/7

5:30 am-6:50 am

Nonstop2h 20m

$237

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Mon 1/5

7:45 am-2:35 pm

1 stop5h 50m

Lambert-St Louis

Wed 1/7

6:20 am-12:15 pm

2 stops6h 55m

$239

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Fri 12/5

12:50 am-10:24 am

1 stop8h 34m

Lambert-St Louis

Sat 12/13

6:00 am-12:51 pm

1 stop7h 51m

$258

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Wed 12/24

4:14 pm-10:16 pm

1 stop5h 02m

Lambert-St Louis

Thu 12/25

7:20 am-3:13 pm

1 stop8h 53m

$281

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Thu 12/18

7:45 am-2:35 pm

1 stop5h 50m

Lambert-St Louis

Sun 12/21

5:35 am-7:00 am

Nonstop2h 25m

$304

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Fri 12/12

5:53 pm-8:57 pm

Nonstop2h 04m

Lambert-St Louis

Sun 12/14

1:35 pm-3:05 pm

Nonstop2h 30m

$307

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Thu 12/25

10:29 pm-7:47 pm

1 stop20h 18m

$62

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/29

Showing 1-10 of 17 results
1
2

Best time to book a flight from Denver to St. Charles

Have a flexible travel schedule? Discover the best time to fly to St. Charles from Denver with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

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

How far ahead should I book a flight from Denver to St. Charles?

Use this chart to determine the optimal time to book a round-trip flight from Denver to St. Charles. Price data was last updated on October 24, 2025.

To ensure you get the cheapest price possible for a flight from Denver to St. Charles, you should look to book at least 74 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.

What is the cheapest month to book a flight from Denver to St. Charles?

Currently, February is the cheapest month in which you can book a flight from Denver to St. Charles (average of $37). Flying from Denver to St. Charles in July is currently the most expensive (average of $126). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from DEN to CH5?

Find hourly flight availability from Denver to St. Charles. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated October 30, 2025.

A simple way to save on the total cost of your ticket is to fly from Denver to St. Charles in the afternoon. If you’re flexible enough to do this you can expect to save up to 28% on your trip compared to booking a flight at noon.

What is the cheapest day to fly from Denver to St. Charles?

Use this chart to determine the cheapest time to fly round-trip from Denver to St. Charles. Price data was last updated on December 16, 2024.

Travelers seeking maximum savings on their Denver to St. Charles flight should consider departing on Friday mornings when fares are most often at their lowest. Monday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.

Reviews of airlines servicing St. Charles

Get insights into the airlines that provide service to St. Charles. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to St. Charles. Reviews last updated October 30, 2025.
See what other customers who have flown with Southwest, United Airlines, and Frontier from Denver to St. Charles have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,243 reviews

Comfort

8.0

Boarding

8.1

Food

7.0

Overall

8.0

Entertainment

7.5

Crew

8.6

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Southwest
8.0
Very good
4,243 reviews
Southwest
8.0
Very good
4,243 reviews

Comfort

8.0

Boarding

8.1

Food

7.0

Overall

8.0

Entertainment

7.5

Crew

8.6

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
United Airlines
7.4
Good
8,996 reviews
Southwest
8.0
Very good
4,243 reviews

Comfort

8.0

Boarding

8.1

Food

7.0

Overall

8.0

Entertainment

7.5

Crew

8.6

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Frontier
5.8
Fair
3,123 reviews
Southwest
8.0
Very good
4,243 reviews

Comfort

8.0

Boarding

8.1

Food

7.0

Overall

8.0

Entertainment

7.5

Crew

8.6

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines

Related info for your journey

Find useful and relevant information for your journey from Denver to St. Charles. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly from for flights from Denver to St. Charles?

    Denver Intl (DEN), located 18.5 mi from the city center, is the airport you fly out of when you book flights from Denver to St. Charles. 4 airlines have flights from Denver Intl to St. Charles on a regular basis. Booking flights from Denver Intl to St. Charles should not be difficult; the airport handles an average of 4 outbound flights to St. Charles per day.

  • How popular is this Denver to St. Charles flight route?

    The Denver Intl to St. Charles flight path was viewed by 37 users in the past month. Keep an eye out for changes in search interest prior to high and low season.

  • How long is the flight from Denver to St. Charles?

    For as low as $197, Frontier can have you in St. Charles from Denver in 2h 05m. Airlines will cover a distance of 767 mi. Both multi-stop and nonstop flights can be found to your destination and back.

  • What are the cheapest airlines to fly from Denver to St. Charles one-way?

    The cheapest airlines for a one-way flight from Denver to St. Charles are Frontier ($62), United Airlines ($79), and Delta ($89).

  • What are the most reliable airlines from Denver to St. Charles?

    The top 3 most reliable airlines when flying from Denver to St. Charles are Frontier (93%), SkyWest Airlines (91%) and United Airlines (89%).

  • What are the cheapest flights from Denver to St. Charles?

    While on average a flight from Denver to St. Charles is generally $221, our data shows the cheapest flight currently is $59. When looking at the most popular route, (Denver Intl - Lambert-St Louis), you can expect to pay $116 for that flight.

  • Can I find deals for flights from Denver to St. Charles that include hotel bookings?

    Yes. In addition to deals on Denver to St. Charles flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Denver to St. Charles?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Denver to St. Charles.

  • Can I find deals for business class flights from Denver to St. Charles?

    Yes. Cheapflights offers flight deals from Denver to St. Charles by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Denver to St. Charles?

    Currently, February is the cheapest month in which you can book a flight from Denver to St. Charles (average of $37). Flying from Denver to St. Charles in July is currently the most expensive (average of $126). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Denver to St. Charles

See prices for flight routes from nearby airports that may be better suited for you.
Denver to Kansas City flights
Denver to St. Louis flights
Denver to Springfield flights
Colorado Springs to Springfield flights
Durango to St. Louis flights
Grand Junction to Springfield flights
Montrose to St. Louis flights
Denver to Columbia flights
Colorado Springs to St. Louis flights
Colorado Springs to Kansas City flights
Durango to Kansas City flights
Grand Junction to St. Louis flights
Montrose to Kansas City flights
Denver to Joplin flights
Grand Junction to Kansas City flights
Hayden to St. Louis flights
Colorado Springs to Joplin flights
Aspen to Kansas City flights
Montrose to Springfield flights
Vail to St. Louis flights
Hayden to Kansas City flights
Durango to Springfield flights
Vail to Kansas City flights
Colorado Springs to Columbia flights
Aspen to St. Louis flights
Gunnison to St. Louis flights
Grand Junction to Joplin flights
Montrose to Joplin flights
Denver to Branson flights

Top 4 airlines flying from Denver to St. Charles

Discover the top 4 airlines that operate flights from Denver to St. Charles. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated October 30, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$54Average$160FlexibilityNo cancel feeOn-time62%
American AirlinesCheapest$136Average$491FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$154Average$302FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$177Average$298FlexibilityNo cancel feeOn-time63%

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.