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 $116 on this airline. Additional options worth looking into are United Airlines and Delta, starting at $210 and $217 round-trip. Frontier is currently priced 42% 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 $108 and $109 on Sun Country Air and Delta, respectively.

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

While on average a flight from Denver to St. Louis is generally $220, our data shows the cheapest flight currently is $69. When looking at the most popular route, (Denver Intl - Lambert-St Louis), you can expect to pay $156 for that flight.

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 (89%), Air Canada (84%).

What are the most popular airlines that fly from Denver to St. Louis?

Consider Frontier, United Airlines or Southwest when booking your flight. These represent the most popular airlines when flying from Denver to St. Louis.

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

Users have found that flying from Denver to St. Louis on a Saturday typically leans towards higher prices. However, this doesn’t mean you still can’t find a deal. Flexibility with other aspects of your flight can still land a great price for your trip.

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

Users have found that booking a flight from Denver to St. Louis at least 59 days early can save you up to 208% on average compared to booking a flight this week. If booking 59 days before your flight isn’t an option for you, users have found flights from Denver to St. Louis for as little as $157 when booking for a departure date within the next two weeks. You can also check prices now. Some users have found airline tickets as low as $286 for flights departing within the next 3 days.

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

Flights from Denver to St. Louis lean towards being more expensive in March. Prices are generally better when you fly from Denver to St. Louis in July, with the cheapest ticket starting at $41.

Most accurate provider : When it comes to deals on Denver-St. Louis flights, users find the pricing of CheapOair to be most consistent on Cheapflights vs. CheapOair Users can find the same prices on Denver-St. Louis flight deals on Cheapflights vs. CheapOair >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 CheapOair the most. CheapOair 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.

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 2h 00m on average. When it comes time to book airfare, you have a few options: there are 7 outbound flights from Denver Intl to Lambert-St Louis offered by 3 different airlines.

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.

$68+ Flights from Denver to St. Louis

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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 Lambert-St Louis are usually found in July or May, booked 78 days in advance, depart on a Saturday or Wednesday and return on a Friday

Cheap flight deals from Denver to St. Louis

Most accurate provider	CheapOair 3 stars
Most trusted provider	CheapOair 3 stars
Round-trip from	$116 (Kiwi.com)
One-way from	$68 (Cheapflightsfares)
Popular in	March
Cheapest in	July
Average price	$166
Good round-trip deal	$196 or less
Good one-way deal	$126 or less

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 Lambert-St Louis

Search Deals

One-way flight from Denver Intl to Lambert-St Louis

Search Deals

Highest demand for flights based on searches. 12% potential increase in price ($29 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 3% potential price decrease ($7 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in May 2025

Search Deals

Price to beat on a round-trip flight from Denver Intl to Lambert-St Louis.

Search Deals

Price to beat on a one-way flight from Denver Intl to Lambert-St Louis.

Search Deals

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 May 1, 2025.

Wed 6/117:00 amDEN - STL

Nonstop2h 08mFrontier

Wed 6/187:29 pmSTL - DEN

Nonstop2h 27mFrontier

Deal found 4/28

$116

Fri 5/306:30 pmDEN - STL

1 stop19h 24mMultiple Airlines

Mon 6/27:24 pmSTL - DEN

Nonstop2h 27mMultiple Airlines

Deal found 4/30

$198

Wed 6/118:40 pmDEN - STL

Nonstop2h 19mUnited Airlines

Tue 6/174:32 pmSTL - DEN

Nonstop2h 29mUnited Airlines

Deal found 4/29

$210

Fri 5/3012:55 amDEN - STL

1 stop7h 40mDelta

Wed 6/41:09 pmSTL - DEN

1 stop5h 30mDelta

Deal found 4/30

$217

Wed 5/2110:25 amDEN - STL

Nonstop2h 05mSouthwest

Tue 5/275:55 amSTL - DEN

Nonstop2h 20mSouthwest

Deal found 4/29

$220

Tue 5/2711:59 pmDEN - STL

1 stop7h 57mAmerican Airlines

Tue 6/310:31 amSTL - DEN

1 stop7h 36mAmerican Airlines

Deal found 4/30

$230

Best flights from Denver to St. Louis
Discover carefully curated flight deals from Denver to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated May 1, 2025.

Wed 6/117:00 amDEN - STL

Nonstop2h 08mFrontier

Wed 6/187:29 pmSTL - DEN

Nonstop2h 27mFrontier

Deal found 4/28

$116

Fri 5/306:30 pmDEN - STL

1 stop19h 24mMultiple Airlines

Mon 6/27:24 pmSTL - DEN

Nonstop2h 27mMultiple Airlines

Deal found 4/30

$198

Wed 6/118:40 pmDEN - STL

Nonstop2h 19mUnited Airlines

Tue 6/174:32 pmSTL - DEN

Nonstop2h 29mUnited Airlines

Deal found 4/29

$210

Fri 5/3012:55 amDEN - STL

1 stop7h 40mDelta

Wed 6/41:09 pmSTL - DEN

1 stop5h 30mDelta

Deal found 4/30

$217

Wed 5/2110:25 amDEN - STL

Nonstop2h 05mSouthwest

Tue 5/275:55 amSTL - DEN

Nonstop2h 20mSouthwest

Deal found 4/29

$220

Tue 5/2711:59 pmDEN - STL

1 stop7h 57mAmerican Airlines

Tue 6/310:31 amSTL - DEN

1 stop7h 36mAmerican Airlines

Deal found 4/30

$230

Last-minute flights from Denver to St. Louis
Discover last-minute flight deals from Denver to St. Louis. Data last updated May 1, 2025 and is based on user searches.

Tue 5/68:20 amDEN - STL

2 stops14h 39mAlaska Airlines

Tue 5/136:30 amSTL - DEN

2 stops15h 45mAlaska Airlines

Deal found 4/28

$611

Fri 5/97:12 pmDEN - STL

1 stop27h 54mFrontier

Mon 5/125:45 pmSTL - DEN

1 stop30h 44mFrontier

Deal found 4/30

$178

Fri 5/912:59 amDEN - STL

1 stop6h 57mDelta

Sat 5/177:30 amSTL - DEN

1 stop5h 34mDelta

Deal found 4/29

$307

Sat 5/108:45 pmDEN - STL

Nonstop2h 13mUnited Airlines

Tue 5/138:48 amSTL - DEN

Nonstop2h 30mUnited Airlines

Deal found 4/29

$342

Sat 5/104:25 pmDEN - STL

1 stop6h 25mSouthwest

Sat 5/1710:00 pmSTL - DEN

Nonstop2h 25mSouthwest

Deal found 4/29

$347

Wed 5/2110:25 amDEN - STL

Nonstop2h 05mSouthwest

Tue 5/275:55 amSTL - DEN

Nonstop2h 20mSouthwest

Deal found 4/29

$220

Tue 5/271:25 pmDEN - STL

Nonstop2h 06mUnited Airlines

Tue 6/34:32 pmSTL - DEN

Nonstop2h 29mUnited Airlines

Deal found 4/29

$223

Tue 5/2711:59 pmDEN - STL

1 stop7h 57mAmerican Airlines

Tue 6/310:31 amSTL - DEN

1 stop7h 36mAmerican Airlines

Deal found 4/30

$230

Fri 5/306:00 amDEN - STL

Nonstop2h 09mFrontier

Mon 6/27:24 pmSTL - DEN

Nonstop2h 27mFrontier

Deal found 4/30

$138

Fri 5/306:30 pmDEN - STL

1 stop19h 24mMultiple Airlines

Mon 6/27:24 pmSTL - DEN

Nonstop2h 27mMultiple Airlines

Deal found 4/30

$198

Fri 5/3012:55 amDEN - STL

1 stop7h 40mDelta

Wed 6/41:09 pmSTL - DEN

1 stop5h 30mDelta

Deal found 4/30

$217

One-way flights from Denver to St. Louis
Search for one-way flight options from Denver to St. Louis. Find affordable one-way fares based on user searches. Data last updated May 1, 2025.

Fri 5/306:00 amDEN - STL

Nonstop2h 09mFrontier

Deal found 4/29

$68

Fri 5/306:30 pmDEN - STL

1 stop19h 24mSun Country Air

Deal found 4/29

$108

Fri 5/3012:59 amDEN - STL

1 stop6h 57mDelta

Deal found 4/30

$109

Tue 7/297:05 pmDEN - STL

Nonstop2h 05mSouthwest

Deal found 4/29

$112

Tue 5/2012:16 pmDEN - STL

1 stop6h 13mAmerican Airlines

Deal found 4/29

$119

Wed 6/116:07 pmDEN - STL

2 stops21h 57mMultiple Airlines

Deal found 4/29

$152

Sun 6/18:40 pmDEN - STL

Nonstop2h 19mUnited Airlines

Deal found 4/29

$154

Thu 5/297:05 pmDEN - STL

2 stops27h 59mAlaska Airlines

Deal found 4/30

$227

Cheapflights Fare Finder

Use the filters below to find and compare flights from Denver to St. Louis that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Wed 6/11

7:00 am-10:08 am

Nonstop2h 08m

Lambert-St Louis

Wed 6/18

7:29 pm-8:56 pm

Nonstop2h 27m

$116

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Fri 5/30

6:30 pm-2:54 pm

1 stop19h 24m

Lambert-St Louis

Mon 6/2

7:24 pm-8:51 pm

Nonstop2h 27m

$198

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Wed 6/11

8:40 pm-11:59 pm

Nonstop2h 19m

Lambert-St Louis

Tue 6/17

4:32 pm-6:01 pm

Nonstop2h 29m

$210

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Fri 5/30

12:55 am-9:35 am

1 stop7h 40m

Lambert-St Louis

Wed 6/4

1:09 pm-5:39 pm

1 stop5h 30m

$217

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Wed 5/21

10:25 am-1:30 pm

Nonstop2h 05m

Lambert-St Louis

Tue 5/27

5:55 am-7:15 am

Nonstop2h 20m

$220

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Tue 5/27

11:59 pm-8:56 am

1 stop7h 57m

Lambert-St Louis

Tue 6/3

10:31 am-5:07 pm

1 stop7h 36m

$230

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Fri 5/30

6:00 am-9:09 am

Nonstop2h 09m

$68

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Fri 5/30

6:30 pm-2:54 pm

1 stop19h 24m

$108

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Fri 7/11

12:59 am-9:04 am

1 stop7h 05m

$109

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Tue 7/29

7:05 pm-10:10 pm

Nonstop2h 05m

$112

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/29

Showing 1-10 of 14 results

Compare providers for flights from Denver to St. Louis

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 May.

Provider	Price Accuracy	Trust Score*
Expedia	Price Accuracy1 star	Trust Score*3 stars
FlightHub	Price Accuracy3 stars	Trust Score*2 stars
eDreams	Price Accuracy3 stars	Trust Score*3 stars
Cheapflightsfares	Price Accuracy3 stars	Trust Score*2 stars
CheapOair	Price Accuracy3 stars	Trust 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 CheapOair to be most consistent on Cheapflights vs. CheapOair Users can find the same prices on Denver-St. Louis flight deals on Cheapflights vs. CheapOair >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 CheapOair the most. CheapOair 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

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.

STL

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

Our travel experts

Taryn White

Expert on STL

Emily Zemler

Expert on DEN

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?

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?

It’s optimal to fly from Denver to St. Louis in the morning. By choosing this option you can save up to 38% on the cost of your flight, compared to a flight at noon.

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

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

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

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 a feel of what it's like to fly with Alaska Airlines, Southwest 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.

Alaska Airlines

8.0

Very good

9,968 reviews

Reviews

1 / 20

10.0

Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

Alaska Airlines

8.0

Very good

9,968 reviews

Alaska Airlines

8.0

Very good

9,968 reviews

Reviews

1 / 20

10.0

Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

Southwest

8.0

Very good

4,294 reviews

Alaska Airlines

8.0

Very good

9,968 reviews

Reviews

1 / 20

10.0

Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

Delta

8.0

Very good

7,934 reviews

Alaska Airlines

8.0

Very good

9,968 reviews

Reviews

1 / 20

10.0

Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

United Airlines

7.4

Good

8,696 reviews

Alaska Airlines

8.0

Very good

9,968 reviews

Reviews

1 / 20

10.0

Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

American Airlines

7.2

Good

10,000 reviews

Alaska Airlines

8.0

Very good

9,968 reviews

Reviews

1 / 20

10.0

Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

Related info for your journey

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 2h 00m on average. When it comes time to book airfare, you have a few options: there are 7 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 $116 on this airline. Additional options worth looking into are United Airlines and Delta, starting at $210 and $217 round-trip. Frontier is currently priced 42% 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 $108 and $109 on Sun Country Air and Delta, 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 (89%), Air Canada (84%).
What are the cheapest flights from Denver to St. Louis?
While on average a flight from Denver to St. Louis is generally $220, our data shows the cheapest flight currently is $69. When looking at the most popular route, (Denver Intl - Lambert-St Louis), you can expect to pay $156 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

Fenton

Maryland Heights

Fairview Heights

Collinsville

Wentzville

Eureka

St. Peters

Festus

Glencoe

Alton

Farmington

O'Fallon

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Other flights to St. Louis

Top 3 airlines flying from Denver to St. Louis

Airline	Cheapest	Average	Flexibility	On-time
Frontier	Cheapest$45	Average$144	FlexibilityNo cancel fee	On-time62%
United Airlines	Cheapest$150	Average$320	FlexibilityNo cancel fee	On-time69%
Southwest	Cheapest$173	Average$300	FlexibilityNo cancel fee	On-time63%

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$68+ 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 5/30. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from Denver to St. Louis with Cheapflights

1. Tell us where you want to go

2. Select your favorite providers

3. Compare prices and book

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

Cheap flight deals from Denver to St. Louis

Most accurate provider

Most trusted provider

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Good round-trip deal

Good one-way deal

Find flight deals from Denver to St. Louis

Cheapest flights from Denver to St. LouisExplore 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 May 1, 2025.

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 May 1, 2025.

Cheapflights Fare Finder

Use the filters below to find and compare flights from Denver to St. Louis that are best for you.

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 May.

The best insider tips for Denver to St. Louis flights

Cheapflights partnered with top experts to bring you the best recommendations for your Denver to St. Louis trip

Airports

DEN

STL

Our travel experts

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.

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 April 25, 2025.

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

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 May 1, 2025.

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 30, 2025.

Rainfall in St. Louis by month

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

Temperature in St. Louis by month

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

Reviews of airlines servicing St. Louis

Get a feel of what it's like to fly with Alaska Airlines, Southwest 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.

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.

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Top 3 airlines flying from Denver to St. Louis

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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 May 1, 2025.