St. Charles

$79+ 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 10/8. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — STL
ago 5 — ago 121
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Cheapflights Tip: The best prices from Denver Intl to St. Charles are usually found in January or February, booked 74 days in advance, depart on a Wednesday or Friday and return on a Wednesday

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 julho 31, 2025.

Round-trip from

$129
(Cheapflightsfares)

One-way from

$79
(Southwest)

Popular in

June

Cheapest in

January

Average price

$220
From Denver Intl to St. Charles
One-way flight from Denver Intl to St. Charles
Highest demand for flights based on searches. 10% potential increase in price ($27 potential increase over avg. RT price).
Cheapest flight prices on average. 3% potential price decrease ($7 potential savings vs. average RT price).
Average for round-trip flights in July 2025

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 julho 31, 2025.

This Cheapflightsfares deal was found by Cheapflights users on 7/30. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sex 9/56:00 amDEN - STL
Nonstop2h 06mFrontier
dom 9/77:55 pmSTL - DEN
Nonstop2h 25mFrontier
Deal found 7/30$129
This Delta deal was found by Cheapflights users on 7/29. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
seg 10/1312:50 amDEN - STL
1 stop6h 15mDelta
ter 10/213:59 pmSTL - DEN
1 stop6h 32mDelta
Deal found 7/29$197
This American Airlines deal was found by Cheapflights users on 7/29. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sex 8/292:05 pmDEN - STL
1 stop5h 13mAmerican Airlines
ter 9/27:23 amSTL - DEN
1 stop5h 01mAmerican Airlines
Deal found 7/29$202

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 julho 31, 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

sex 9/5

6:00 am-9:06 am

Nonstop2h 06m

Lambert-St Louis

dom 9/7

7:55 pm-9:20 pm

Nonstop2h 25m

$129

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

seg 10/13

12:50 am-8:05 am

1 stop6h 15m

Lambert-St Louis

ter 10/21

3:59 pm-9:31 pm

1 stop6h 32m

$197

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

sex 8/29

2:05 pm-8:18 pm

1 stop5h 13m

Lambert-St Louis

ter 9/2

7:23 am-11:24 am

1 stop5h 01m

$202

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

sex 8/29

5:30 am-8:30 am

Nonstop2h 00m

Lambert-St Louis

seg 9/1

5:45 am-7:00 am

Nonstop2h 15m

$217

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

qua 10/8

5:15 pm-8:15 pm

Nonstop2h 00m

$79

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

sáb 11/15

8:00 am-3:35 pm

1 stop6h 35m

$93

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

sáb 8/30

2:05 pm-8:50 pm

1 stop5h 45m

$94

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

qui 10/16

12:50 am-8:05 am

1 stop6h 15m

$109

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

sáb 8/30

8:40 pm-11:53 pm

Nonstop2h 13m

$114

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

qui 8/14

6:13 pm-11:30 am

1 stop16h 17m

$138

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/31

Showing 1-10 of 11 results
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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 July 25, 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, August is the cheapest month in which you can book a flight from Denver to St. Charles (average of $311). Flying from Denver to St. Charles in March is currently the most expensive (average of $356). 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 julho 31, 2025.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Denver to St. Charles as you normally would.

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 evenings 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.

Weekly flight availability from Denver to St. Charles

Explore weekly flight availability from Denver to St. Charles. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated julho 31, 2025.

The most flights from DEN to CH5 are scheduled on a Monday (17 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (4 on average).

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 julho 31, 2025.
See what other customers who have flown with Southwest, Delta, and United Airlines 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.

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Food

7.0

Overall

8.0

Crew

8.6

Reviews

1 / 20
8.0
Excellent

Gina,Jul 2025

LAS - DEN

We experienced bad weather, which turned our 1.5 hour flight from Las Vegas to Denver, into 3.5. The pilot and crew kept us updated and explained that we had to circle and or possibly redirect to another airport. After circling for sometime, we were able to land smoothly in Denver. Thank you to all the flight crew, tower control, and all who got us to our destination safely.

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Food

7.0

Overall

8.0

Crew

8.6

Reviews

1 / 20
8.0
Excellent

Gina,Jul 2025

LAS - DEN

We experienced bad weather, which turned our 1.5 hour flight from Las Vegas to Denver, into 3.5. The pilot and crew kept us updated and explained that we had to circle and or possibly redirect to another airport. After circling for sometime, we were able to land smoothly in Denver. Thank you to all the flight crew, tower control, and all who got us to our destination safely.
8.0
Very good

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Food

7.0

Overall

8.0

Crew

8.6

Reviews

1 / 20
8.0
Excellent

Gina,Jul 2025

LAS - DEN

We experienced bad weather, which turned our 1.5 hour flight from Las Vegas to Denver, into 3.5. The pilot and crew kept us updated and explained that we had to circle and or possibly redirect to another airport. After circling for sometime, we were able to land smoothly in Denver. Thank you to all the flight crew, tower control, and all who got us to our destination safely.

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Food

7.0

Overall

8.0

Crew

8.6

Reviews

1 / 20
8.0
Excellent

Gina,Jul 2025

LAS - DEN

We experienced bad weather, which turned our 1.5 hour flight from Las Vegas to Denver, into 3.5. The pilot and crew kept us updated and explained that we had to circle and or possibly redirect to another airport. After circling for sometime, we were able to land smoothly in Denver. Thank you to all the flight crew, tower control, and all who got us to our destination safely.

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Food

7.0

Overall

8.0

Crew

8.6

Reviews

1 / 20
8.0
Excellent

Gina,Jul 2025

LAS - DEN

We experienced bad weather, which turned our 1.5 hour flight from Las Vegas to Denver, into 3.5. The pilot and crew kept us updated and explained that we had to circle and or possibly redirect to another airport. After circling for sometime, we were able to land smoothly in Denver. Thank you to all the flight crew, tower control, and all who got us to our destination safely.

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Food

7.0

Overall

8.0

Crew

8.6

Reviews

1 / 20
8.0
Excellent

Gina,Jul 2025

LAS - DEN

We experienced bad weather, which turned our 1.5 hour flight from Las Vegas to Denver, into 3.5. The pilot and crew kept us updated and explained that we had to circle and or possibly redirect to another airport. After circling for sometime, we were able to land smoothly in Denver. Thank you to all the flight crew, tower control, and all who got us to our destination safely.

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 11 outbound flights to St. Charles per day.

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

  • 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 Southwest ($79), Frontier ($93), and American Airlines ($94).

  • 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 (91%), United Airlines (72%) and Air Canada (64%).

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

    While on average a flight from Denver to St. Charles is generally $187, our data shows the cheapest flight currently is $78. When looking at the most popular route, (Denver Intl - Lambert-St Louis), you can expect to pay $126 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, August is the cheapest month in which you can book a flight from Denver to St. Charles (average of $311). Flying from Denver to St. Charles in March is currently the most expensive (average of $356). 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.

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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 julho 31, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$47Average$154FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$152Average$326FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$177Average$298FlexibilityNo cancel feeOn-time63%
American AirlinesCheapest$326Average$471FlexibilityNo cancel feeOn-time71%

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