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$58+ Cheap flights from St. Louis to Denver (STL - DEN)

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 4/5. Fares are subject to change and may not be available on all flights or dates of travel.
STL — DEN
Mar 2 — Mar 91
Sun 3/2
Sun 3/9
1 adult, Economy
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The best prices from Lambert-St Louis to Denver Intl are usually found in April or May, booked 23 days in advance, depart on a Friday or Wednesday and return on a Wednesday

Cheap flight deals from St. Louis to Denver

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Denver (DEN). 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 February 25, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$116
(Cheapflightsfares)

One-way from

$58
(Cheapflightsfares)

Popular in

March

Cheapest in

April

Average price

$197

Good round-trip deal

$201 or less

Good one-way deal

$136 or less
Provider with most accurate pricing for Lambert-St Louis-Denver Intl flight deals.
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Provider most trusted by Cheapflights users for Lambert-St Louis-Denver Intl flights.
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From Lambert-St Louis to Denver Intl
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One-way flight from Lambert-St Louis to Denver Intl
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Highest demand for flights based on searches. 8% potential increase in price ($16 potential increase over avg. RT price).
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Cheapest flight prices on average. 4% potential price decrease ($8 potential savings vs. average RT price).
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Average for round-trip flights in February 2025
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Price to beat on a round-trip flight from Lambert-St Louis to Denver Intl.
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Price to beat on a one-way flight from Lambert-St Louis to Denver Intl.
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Find flight deals from St. Louis to Denver

Cheapest flights from St. Louis to Denver
Explore the most affordable flight options available from St. Louis to Denver. Find the lowest fares from popular airlines and budget airlines, with prices last updated on February 25, 2025.

This Kiwi.com deal was found by Cheapflights users on 2/24. 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 6/116:55 pmSTL - DEN
Nonstop2h 31mFrontier
Mon 6/166:00 amDEN - STL
Nonstop2h 12mFrontier
Deal found 2/24$115
This Booking.com deal was found by Cheapflights users on 2/24. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/288:15 amSTL - DEN
1 stop9h 20mMultiple Airlines
Thu 5/812:00 pmDEN - STL
Nonstop2h 07mMultiple Airlines
Deal found 2/24$183
This Delta deal was found by Cheapflights users on 2/24. 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.
Wed 3/266:00 amSTL - DEN
1 stop6h 15mDelta
Tue 4/112:55 amDEN - STL
1 stop7h 19mDelta
Deal found 2/24$217
This Southwest deal was found by Cheapflights users on 2/24. 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.
Thu 4/310:45 pmSTL - DEN
Nonstop2h 25mSouthwest
Mon 4/77:55 pmDEN - STL
Nonstop2h 00mSouthwest
Deal found 2/24$225
This United deal was found by Cheapflights users on 2/25. 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 is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/111:43 pmSTL - DEN
Nonstop2h 30mUnited Airlines
Tue 4/156:44 pmDEN - STL
Nonstop2h 06mUnited Airlines
Deal found 2/25$267
This American Airlines deal was found by Cheapflights users on 2/24. 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.
Wed 3/195:10 amSTL - DEN
1 stop7h 31mAmerican Airlines
Wed 3/2611:59 pmDEN - STL
1 stop7h 10mAmerican Airlines
Deal found 2/24$277

Find flights from St. Louis to Denver within your budget

Customize your flight search to find flights from St. Louis to Denver 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 February 25, 2025.

Fly from

St. Louis

Fly to

Denver

Route

Depart

Return

Price

St. LouisDenver

STL - DEN

STLDEN

Lambert-St Louis

Sat 4/12

6:51 pm-8:22 pm

Nonstop2h 31m

Denver Intl

Sat 4/19

6:00 am-9:06 am

Nonstop2h 06m

$116

St. LouisDenver

STL - DEN

STLDEN

Lambert-St Louis

Sat 4/12

9:41 am-3:51 pm

1 stop7h 10m

Denver Intl

Sat 4/19

4:07 pm-10:12 pm

1 stop5h 05m

$169

St. LouisDenver

STL - DEN

STLDEN

Lambert-St Louis

Sat 4/12

6:00 am-11:08 am

1 stop6h 08m

Denver Intl

Fri 4/18

12:55 am-9:47 am

1 stop7h 52m

$197

St. LouisDenver

STL - DEN

STLDEN

Lambert-St Louis

Mon 3/17

10:45 pm-12:10 am

Nonstop2h 25m

Denver Intl

Mon 3/24

9:55 pm-12:55 am

Nonstop2h 00m

$225

St. LouisDenver

STL - DEN

STLDEN

Lambert-St Louis

Mon 3/17

6:58 pm-8:29 pm

Nonstop2h 31m

Denver Intl

Thu 3/20

6:55 pm-11:34 am

1 stop15h 39m

$263

St. LouisDenver

STL - DEN

STLDEN

Lambert-St Louis

Fri 4/11

1:43 pm-3:13 pm

Nonstop2h 30m

Denver Intl

Tue 4/15

6:44 pm-9:50 pm

Nonstop2h 06m

$267

St. LouisDenver

STL - DEN

STLDEN

Lambert-St Louis

Wed 4/16

6:44 am-1:53 pm

2 stops32h 09m

Denver Intl

Thu 4/17

5:38 pm-11:59 pm

1 stop29h 21m

$411

St. LouisDenver

STL - DEN

STLDEN

Lambert-St Louis

Sat 4/5

6:51 pm-8:22 pm

Nonstop2h 31m

$58

St. LouisDenver

STL - DEN

STLDEN

Lambert-St Louis

Wed 4/16

5:45 am-10:23 am

1 stop5h 38m

$85

St. LouisDenver

STL - DEN

STLDEN

Lambert-St Louis

Tue 3/25

8:20 am-9:53 am

Nonstop2h 33m

$95

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/25

Showing 1-10 of 15 results
1
2

Compare providers for flights from St. Louis to Denver

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 St. Louis to Denver in February.
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
CheapTicketsDealPrice Accuracy3 starsTrust Score*3 stars
GotogatePrice Accuracy3 starsTrust Score*3 stars
FlightnetworkPrice Accuracy-Trust Score*3 stars
AranGrantPrice Accuracy3 starsTrust Score*1 star
CheapOairPrice Accuracy1 starTrust Score*3 stars
PricelinePrice 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 St. Louis-Denver flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on St. Louis-Denver flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from St. Louis-Denver flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on St. Louis-Denver 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 St. Louis-Denver flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

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

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

Travel insights for flights from St. Louis to Denver

Get recent, data-driven insights about flights from St. Louis to Denver including ideal travel times, pricing trends, and more.

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

Use this chart to determine the optimal time to book a round-trip flight from St. Louis to Denver. Price data was last updated on February 14, 2025.

Booking 23 days in advance of your planned departure date is, on average, the best time to get cheap flights from St. Louis to Denver. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

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

Currently, October is the cheapest month in which you can book a flight from St. Louis to Denver (average of $197). Flying from St. Louis to Denver in March is currently the most expensive (average of $278). 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 STL to DEN?

Find hourly flight availability from St. Louis to Denver. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated February 25, 2025.

It’s optimal to fly from St. Louis to Denver in the evening. By choosing this option you can save up to 69% on the cost of your flight, compared to a flight in the morning.

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

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

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

Weekly flight availability from St. Louis to Denver

Explore weekly flight availability from St. Louis to Denver. 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 February 25, 2025.

The most flights from STL to DEN are scheduled on a Monday (14 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (5 on average).

Rainfall in Denver by month

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

In terms of precipitation, rainfall in Denver ranges from 0.5 - 2.3 inches per month. May is typically the wettest month, when rainfall can reach 2.3 in. January is typically the driest time to visit Denver when rainfall is around 0.5 in.

Temperature in Denver by month

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

If weather is an important factor for your trip to Denver, 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 73.4 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 30.2 F).

Reviews of airlines servicing Denver

Get insights into the airlines that provide service to Denver. 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 Denver. Reviews last updated February 25, 2025.
Read through reviews of airlines operating flights from St. Louis to Denver, such as Southwest, Alaska Airlines and Delta. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.1
Very good
4,374 reviews

Entertainment

7.6

Overall

8.1

Crew

8.7

Food

7.1

Boarding

8.2

Comfort

8.1

Reviews

1 / 20

2.0
Mediocre

Steven,Feb 2025

BZN - DEN

Bozeman Airport knows how to deal with snow. I saw many airlines leave with only small delays due to the foot of snow. Our plane was 4 hours delayed. I missed my connection in Denver with a 3.5 hour layover. Because of that, the best you Southwest could do was make me wait more hours, them send me to Chicago Midway, where I had to wait overnight, for 7 more hours until a flight to RSW was available. Nobody at Southwest told me that Midway shuts down after 8pm. Everything was closed. I had no idea. You just dumped me there. I am a 65 year old man and you dumped me in Midway without even a couch to lie on. I was awake 21 hours because of this. No, it was not an act of God. Other airlines were moving passengers out. It was incompetence Shame on you.

Southwest
8.1
Very good
4,374 reviews
Southwest
8.1
Very good
4,374 reviews

Entertainment

7.6

Overall

8.1

Crew

8.7

Food

7.1

Boarding

8.2

Comfort

8.1

Reviews

1 / 20

2.0
Mediocre

Steven,Feb 2025

BZN - DEN

Bozeman Airport knows how to deal with snow. I saw many airlines leave with only small delays due to the foot of snow. Our plane was 4 hours delayed. I missed my connection in Denver with a 3.5 hour layover. Because of that, the best you Southwest could do was make me wait more hours, them send me to Chicago Midway, where I had to wait overnight, for 7 more hours until a flight to RSW was available. Nobody at Southwest told me that Midway shuts down after 8pm. Everything was closed. I had no idea. You just dumped me there. I am a 65 year old man and you dumped me in Midway without even a couch to lie on. I was awake 21 hours because of this. No, it was not an act of God. Other airlines were moving passengers out. It was incompetence Shame on you.

Alaska Airlines
8.0
Very good
9,713 reviews
Southwest
8.1
Very good
4,374 reviews

Entertainment

7.6

Overall

8.1

Crew

8.7

Food

7.1

Boarding

8.2

Comfort

8.1

Reviews

1 / 20

2.0
Mediocre

Steven,Feb 2025

BZN - DEN

Bozeman Airport knows how to deal with snow. I saw many airlines leave with only small delays due to the foot of snow. Our plane was 4 hours delayed. I missed my connection in Denver with a 3.5 hour layover. Because of that, the best you Southwest could do was make me wait more hours, them send me to Chicago Midway, where I had to wait overnight, for 7 more hours until a flight to RSW was available. Nobody at Southwest told me that Midway shuts down after 8pm. Everything was closed. I had no idea. You just dumped me there. I am a 65 year old man and you dumped me in Midway without even a couch to lie on. I was awake 21 hours because of this. No, it was not an act of God. Other airlines were moving passengers out. It was incompetence Shame on you.

Delta
8.0
Very good
8,163 reviews
Southwest
8.1
Very good
4,374 reviews

Entertainment

7.6

Overall

8.1

Crew

8.7

Food

7.1

Boarding

8.2

Comfort

8.1

Reviews

1 / 20

2.0
Mediocre

Steven,Feb 2025

BZN - DEN

Bozeman Airport knows how to deal with snow. I saw many airlines leave with only small delays due to the foot of snow. Our plane was 4 hours delayed. I missed my connection in Denver with a 3.5 hour layover. Because of that, the best you Southwest could do was make me wait more hours, them send me to Chicago Midway, where I had to wait overnight, for 7 more hours until a flight to RSW was available. Nobody at Southwest told me that Midway shuts down after 8pm. Everything was closed. I had no idea. You just dumped me there. I am a 65 year old man and you dumped me in Midway without even a couch to lie on. I was awake 21 hours because of this. No, it was not an act of God. Other airlines were moving passengers out. It was incompetence Shame on you.

United Airlines
7.4
Good
8,734 reviews
Southwest
8.1
Very good
4,374 reviews

Entertainment

7.6

Overall

8.1

Crew

8.7

Food

7.1

Boarding

8.2

Comfort

8.1

Reviews

1 / 20

2.0
Mediocre

Steven,Feb 2025

BZN - DEN

Bozeman Airport knows how to deal with snow. I saw many airlines leave with only small delays due to the foot of snow. Our plane was 4 hours delayed. I missed my connection in Denver with a 3.5 hour layover. Because of that, the best you Southwest could do was make me wait more hours, them send me to Chicago Midway, where I had to wait overnight, for 7 more hours until a flight to RSW was available. Nobody at Southwest told me that Midway shuts down after 8pm. Everything was closed. I had no idea. You just dumped me there. I am a 65 year old man and you dumped me in Midway without even a couch to lie on. I was awake 21 hours because of this. No, it was not an act of God. Other airlines were moving passengers out. It was incompetence Shame on you.

American Airlines
7.2
Good
10,000 reviews
Southwest
8.1
Very good
4,374 reviews

Entertainment

7.6

Overall

8.1

Crew

8.7

Food

7.1

Boarding

8.2

Comfort

8.1

Reviews

1 / 20

2.0
Mediocre

Steven,Feb 2025

BZN - DEN

Bozeman Airport knows how to deal with snow. I saw many airlines leave with only small delays due to the foot of snow. Our plane was 4 hours delayed. I missed my connection in Denver with a 3.5 hour layover. Because of that, the best you Southwest could do was make me wait more hours, them send me to Chicago Midway, where I had to wait overnight, for 7 more hours until a flight to RSW was available. Nobody at Southwest told me that Midway shuts down after 8pm. Everything was closed. I had no idea. You just dumped me there. I am a 65 year old man and you dumped me in Midway without even a couch to lie on. I was awake 21 hours because of this. No, it was not an act of God. Other airlines were moving passengers out. It was incompetence Shame on you.

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Denver. 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 St. Louis to Denver?

    You will need to book a flight from Lambert-St Louis to Denver Intl if you want to fly from St. Louis to Denver. At least 5 different airlines have flights from Lambert-St Louis (STL) to Denver Intl (DEN) on a regular basis. There are 8 flights to Denver from the St. Louis airport per day. If you manage to book one that is nonstop, then you can expect the flight time from STL to DEN to be around 2h 18m.

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

    Flights from Lambert-St Louis to Denver Intl have been viewed 213 times in the past calendar month.

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

    Frontier, at $116, was found to be the cheapest airline from St. Louis to Denver.Alternate airlines to your destination round-trip include American Airlines and Delta. Users have found that Frontier is 35% cheaper than the other options available to this destination.

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

    One-way options have recently been found by users for as low as $58 on Frontier. Other airlines that offer cheap prices include American Airlines from $85 and United Airlines from $95 one-way.

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

    No one likes to see their flight delayed. When booking a flight from St. Louis to Denver consider choosing Frontier (93%), Air Canada (81%) or United Airlines (76%) as they are the most reliable in getting you off to your destination on time.

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

    Looking for the cheapest flight from St. Louis to Denver? While on average our users pay $634, our data indicates the cheapest price to be $44. The most popular route (Lambert-St Louis - Denver Intl), is priced around $168.

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

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

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

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

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

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

    Currently, October is the cheapest month in which you can book a flight from St. Louis to Denver (average of $197). Flying from St. Louis to Denver in March is currently the most expensive (average of $278). 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 St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
Westminster
Black Hawk
Winter Park
Lakewood
Broomfield
Cripple Creek
Silverthorne
Golden
Brighton
Keystone
Frisco
Wheat Ridge
Grand Lake
Idaho Springs
Greeley
Central City
Copper Mountain
Longmont
Thornton
Limon

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Alternative routes for St. Louis to Denver

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Top 5 airlines flying from St. Louis to Denver

Discover the top 5 airlines that operate flights from St. Louis to Denver. 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 February 25, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$45Average$115FlexibilityNo cancel feeOn-time62%
DeltaCheapest$131Average$255FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$150Average$314FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$177Average$295FlexibilityNo cancel feeOn-time63%
American AirlinesCheapest$192Average$258FlexibilityNo cancel feeOn-time71%
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