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$67+ Cheap flights from Denver to St. Louis (DEN - STL)

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 6/28. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — STL
Apr 1 — Apr 81
Tue 4/1
Tue 4/8
1 adult, Economy
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Find cheap flights from Denver to St. Louis with Cheapflights

1. Tell us where you want to go
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Cheapflights Tip: The best prices from Denver Intl to Lambert-St Louis are usually found in May or July, booked 78 days in advance, depart on a Wednesday or Saturday and return on a Friday

Cheap flight deals from Denver to St. Louis

Discover tips and strategies to find the most affordable flight options for your journey from Denver (DEN) to St. Louis (STL). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated March 27, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$130
(Frontier)

One-way from

$68
(Kiwi.com)

Popular in

November

Cheapest in

May

Average price

$226

Good round-trip deal

$151 or less

Good one-way deal

$107 or less
Provider with most accurate pricing for Denver Intl-Lambert-St Louis flight deals.
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Provider most trusted by Cheapflights users for Denver Intl-Lambert-St Louis flights.
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From Denver Intl to Lambert-St Louis
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One-way flight from Denver Intl to Lambert-St Louis
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Highest demand for flights based on searches. 11% potential increase in price ($26 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($4 potential savings vs. average RT price).
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Average for round-trip flights in March 2025
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Price to beat on a round-trip flight from Denver Intl to Lambert-St Louis.
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Price to beat on a one-way flight from Denver Intl to Lambert-St Louis.
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Find flight deals from Denver to St. Louis

Cheapest flights from Denver to St. Louis
Explore the most affordable flight options available from Denver to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 27, 2025.

This Kiwi.com deal was found by Cheapflights users on 3/26. 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 4/236:55 amDEN - STL
Nonstop2h 06mFrontier
Wed 4/306:58 pmSTL - DEN
Nonstop2h 31mFrontier
Deal found 3/26$137
This Southwest deal was found by Cheapflights users on 3/26. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/296:30 amDEN - STL
1 stop5h 45mSouthwest
Wed 4/308:00 amSTL - DEN
Nonstop2h 20mSouthwest
Deal found 3/26$207
This American Airlines deal was found by Cheapflights users on 3/26. 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.
Mon 4/2811:59 pmDEN - STL
1 stop7h 31mAmerican Airlines
Tue 4/299:41 amSTL - DEN
1 stop7h 10mAmerican Airlines
Deal found 3/26$212
This Delta deal was found by Cheapflights users on 3/26. 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.
Thu 4/246:12 pmDEN - STL
1 stop4h 22mDelta
Sat 4/267:10 amSTL - DEN
1 stop6h 12mDelta
Deal found 3/26$234
This Sun Country Air deal was found by Cheapflights users on 3/26. 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 Sun Country Air is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/256:40 pmDEN - STL
1 stop15h 42mSun Country Air
Sun 5/48:00 amSTL - DEN
1 stop10h 21mSun Country Air
Deal found 3/26$235
This CheapOair deal was found by Cheapflights users on 3/26. 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 6/65:01 pmDEN - STL
1 stop17h 24mMultiple Airlines
Mon 6/97:24 pmSTL - DEN
Nonstop2h 27mMultiple Airlines
Deal found 3/26$249
This United Airlines deal was found by Cheapflights users on 3/26. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/266:44 pmDEN - STL
Nonstop2h 06mUnited Airlines
Mon 4/285:35 pmSTL - DEN
1 stop6h 35mUnited Airlines
Deal found 3/26$274
This Alaska Airlines deal was found by Cheapflights users on 3/26. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/228:20 amDEN - STL
2 stops14h 39mAlaska Airlines
Wed 4/236:30 amSTL - DEN
2 stops15h 45mAlaska Airlines
Deal found 3/26$379

Cheapflights Fare Finder

Customize your flight search to find flights from Denver to St. Louis 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 March 27, 2025.
Use the filters below to find and compare flights from Denver to St. Louis that are best for you.

Fly from

Denver

Fly to

St. Louis

Route

Depart

Return

Price

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Wed 4/23

6:55 am-10:01 am

Nonstop2h 06m

Lambert-St Louis

Wed 4/30

6:58 pm-8:29 pm

Nonstop2h 31m

$137

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Tue 4/29

6:30 am-1:15 pm

1 stop5h 45m

Lambert-St Louis

Wed 4/30

8:00 am-9:20 am

Nonstop2h 20m

$207

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Mon 4/28

11:59 pm-8:30 am

1 stop7h 31m

Lambert-St Louis

Tue 4/29

9:41 am-3:51 pm

1 stop7h 10m

$212

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Thu 4/24

6:12 pm-11:34 pm

1 stop4h 22m

Lambert-St Louis

Sat 4/26

7:10 am-12:22 pm

1 stop6h 12m

$234

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Fri 4/25

6:40 pm-11:22 am

1 stop15h 42m

Lambert-St Louis

Sun 5/4

8:00 am-5:21 pm

1 stop10h 21m

$235

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Fri 6/6

5:01 pm-11:25 am

1 stop17h 24m

Lambert-St Louis

Mon 6/9

7:24 pm-8:51 pm

Nonstop2h 27m

$249

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Sat 4/26

6:44 pm-9:50 pm

Nonstop2h 06m

Lambert-St Louis

Mon 4/28

5:35 pm-11:10 pm

1 stop6h 35m

$274

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Tue 4/22

8:20 am-11:59 pm

2 stops14h 39m

Lambert-St Louis

Wed 4/23

6:30 am-9:15 pm

2 stops15h 45m

$379

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Sat 6/28

6:00 am-9:12 am

Nonstop2h 12m

$67

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Tue 7/8

9:40 am-12:46 pm

Nonstop2h 06m

$99

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/26

Showing 1-10 of 16 results
1
2

Compare providers for flights from Denver to St. Louis

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Denver to St. Louis in March.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
CheapflightsfaresPrice Accuracy3 starsTrust Score*2 stars
CheapOairPrice Accuracy1 starTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Denver-St. Louis flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Denver-St. Louis flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Denver-St. Louis flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Denver-St. Louis flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Denver-St. Louis flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

The best insider tips for Denver to St. Louis flights

Snippets provided in this section are AI-generated based on a summarization of Cheapflights-commissioned articles. The articles are presented as-is, for general informational purposes only, and may not be up-to-date. The opinions contained in the articles are original to the author and reflect their authentic experience, which may vary significantly from the experience of others.
Cheapflights partnered with top experts to bring you the best recommendations for your Denver to St. Louis trip
Airports
DEN

Use the A Line train for a quick, cost-effective trip from downtown Denver to DEN, running every 15 minutes.

Read more about DENby Emily Zemler
STL

Take the MetroLink light rail from STL to downtown St. Louis in about 40 minutes, a convenient and affordable option.

Read more about STLby Taryn White
Our travel experts
Taryn White

Taryn White

Expert on STL

Taryn White

Taryn White

Taryn White is a freelance travel writer, digital creator, and travel advisor who has visited nearly 100 countries and all 50 states. She’s familiar with many airports and enjoys beach hopping, boutique hotels, spa experiences, and exploring local culture. Her work has appeared in Travel + Leisure, Condé Nast Traveler, National Geographic, Smithsonian Magazine, AFAR, and more.

Read more
Emily Zemler

Emily Zemler

Expert on DEN

Emily Zemler

Emily Zemler

Emily is a freelance writer and book author based in London covering entertainment and travel. Her work has appeared in Los Angeles Times, Observer, and Conde Nast Traveler She has ventured to more than 40 countries and all seven continents, always in search of a great art museum. She has written extensively about hotels, luxury travel, and aviation.

Read more

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

Have a flexible travel schedule? Discover the best time to fly to St. Louis 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. Louis

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

Use this chart to determine the optimal time to book a round-trip flight from Denver to St. Louis. Price data was last updated on March 21, 2025.

The price you pay for your flight from Denver to St. Louis may vary depending on when you book. For the best chance of a lower fare, look to book 78 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

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

Currently, August is the cheapest month in which you can book a flight from Denver to St. Louis (average of $311). Flying from Denver to St. Louis 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 STL?

Find hourly flight availability from Denver to St. Louis. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated March 27, 2025.

It’s optimal to fly from Denver to St. Louis in the morning. By choosing this option you can save up to 39% on the cost of your flight, compared to a flight at noon.

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

Use this chart to determine the cheapest time to fly round-trip from Denver to St. Louis. Price data was last updated on March 23, 2025.

Travelers seeking maximum savings on their Denver to St. Louis flight should consider departing on Wednesday 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.

Rainfall in St. Louis by month

Plan your trip to St. Louis by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in St. Louis ranges from 2.2 - 4.7 inches per month. May is typically the wettest month, when rainfall can reach 4.7 in. February is typically the driest time to visit St. Louis when rainfall is around 2.2 in.

Temperature in St. Louis by month

Plan your trip to St. Louis by taking into account the average temperature totals by month.

If weather is an important factor for your trip to St. Louis, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 80.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 32.0 F).

Reviews of airlines servicing St. Louis

Get insights into the airlines that provide service to St. Louis. 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. Louis. Reviews last updated March 27, 2025.
Get a feel of what it's like to fly with Southwest, Alaska Airlines and Delta from Denver to St. Louis by reading reviews from past customers. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.1
Very good
4,273 reviews

Boarding

8.2

Overall

8.1

Food

7.1

Entertainment

7.6

Comfort

8.1

Crew

8.6

Reviews

1 / 20
8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.
Southwest
8.1
Very good
4,273 reviews
Southwest
8.1
Very good
4,273 reviews

Boarding

8.2

Overall

8.1

Food

7.1

Entertainment

7.6

Comfort

8.1

Crew

8.6

Reviews

1 / 20
8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.
Alaska Airlines
8.0
Very good
9,795 reviews
Southwest
8.1
Very good
4,273 reviews

Boarding

8.2

Overall

8.1

Food

7.1

Entertainment

7.6

Comfort

8.1

Crew

8.6

Reviews

1 / 20
8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.
Delta
8.0
Very good
7,895 reviews
Southwest
8.1
Very good
4,273 reviews

Boarding

8.2

Overall

8.1

Food

7.1

Entertainment

7.6

Comfort

8.1

Crew

8.6

Reviews

1 / 20
8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.
United Airlines
7.4
Good
8,603 reviews
Southwest
8.1
Very good
4,273 reviews

Boarding

8.2

Overall

8.1

Food

7.1

Entertainment

7.6

Comfort

8.1

Crew

8.6

Reviews

1 / 20
8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.
American Airlines
7.2
Good
10,000 reviews
Southwest
8.1
Very good
4,273 reviews

Boarding

8.2

Overall

8.1

Food

7.1

Entertainment

7.6

Comfort

8.1

Crew

8.6

Reviews

1 / 20
8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

Related info for your journey

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

  • What airports do I use to fly from Denver to St. Louis?

    To fly from Denver to St. Louis, you need to book a flight from Denver Intl (DEN) to Lambert-St Louis (STL). Nonstop flights to Lambert-St Louis from Denver Intl take 1h 56m on average. When it comes time to book airfare, you have a few options: there are 10 outbound flights from Denver Intl to Lambert-St Louis offered by 3 different airlines.

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

    Within the past month, 27 users have taken a look at flights from Denver Intl to Lambert-St Louis.

  • What are the cheapest airlines flying from Denver to St. Louis round-trip?

    Our cheapest airline available from Denver to St. Louis is Frontier. Our recent data shows that you can find tickets from as low as $130 on this airline. Additional options worth looking into are Southwest and American Airlines, starting at $207 and $212 round-trip. Frontier is currently priced 32% below the average price you’ll pay for this route.

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

    For one-way options, check prices for Frontier. According to our data, you can fly for as low as $68. Users have also found prices from $100 and $108 on American Airlines and Sun Country Air, respectively.

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

    Looking for the most reliable airlines to get you to your destination on time? Our data shows these are most likely to get you from Denver to St. Louis on time: Sun Country Air (100%), Frontier (91%), Air Canada (88%).

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

    While on average a flight from Denver to St. Louis is generally $234, our data shows the cheapest flight currently is $35. When looking at the most popular route, (Denver Intl - Lambert-St Louis), you can expect to pay $172 for that flight.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Denver to St. Louis 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. Louis?

    Currently, August is the cheapest month in which you can book a flight from Denver to St. Louis (average of $311). Flying from Denver to St. Louis 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.

See more FAQs

Traveling to a place near Denver?

Book flights to Denver if you plan to visit one of these locations
Fenton
Fairview Heights
Maryland Heights
Collinsville
Wentzville
Eureka
St. Peters
Festus
Glencoe
Alton
Farmington
Chesterfield

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Alternative routes for Denver to St. Louis

See prices for flight routes from nearby airports that may be better suited for you.
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Top 3 airlines flying from Denver to St. Louis

Discover the top 3 airlines that operate flights from Denver to St. Louis. 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 March 27, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$45Average$141FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$149Average$321FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$154Average$298FlexibilityNo cancel feeOn-time63%
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