Cheap flights from St. Louis to Denver (STL - DEN) from $29

This is the cheapest one-way flight price, found on 9/27. Prices may vary by date and flight preferences.
STL — DEN
Oct 3 — Oct 101

The best prices from Lambert-St Louis to Denver Intl are usually found in February or January, booked 19 days in advance, depart on a Tuesday or Saturday and return on a Saturday

How to find the cheapest flight from St. Louis (STL) to Denver (DEN)

All the information you need to plan the best STL to DEN flight in 2023: compare St. Louis to Denver flight prices with the expected peak season, weather and rainfall in Denver.

Popular in

June

Cheapest in

February

Round-trip from

$197

One-way from

$91
High demand for flights, 27% potential price rise
Best time to find cheap flights, 34% potential price drop
From Lambert-St Louis to Denver Intl
One-way flight from Lambert-St Louis to Denver Intl

STL - DEN

Price

$197 - $392

DEN

Temperature

30.2 - 73.4 °F

DEN

Rainfall

0.5 - 2.3 inches

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

Tuesday flights are generally found to be more expensive for flights from St. Louis to Denver. This shouldn’t discourage you from searching, as you can still find great deals by being flexible with your options. Use our search form to find deals on tickets to Denver.

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

Find a great deal and save up to 10% by booking at least 15 days prior to your desired departure date, rather than waiting until the week of travel. According to our data, there are a number of flights available from St. Louis to Denver within the next two weeks, with the cheapest ticket starting at $185.

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

February can be a great time to fly to Denver from St. Louis with a flight ticket averaging about $194. Cheapflights users have found deals in the month of February for as cheap as $67. The most expensive prices can be found in the month of June.

When is the cheapest time to fly from St. Louis to Denver (STL - DEN)?

It’s optimal to fly from St. Louis to Denver in the afternoon. By choosing this option you can save up to 42% on the cost of your flight, compared to a flight at noon.

Cheap Frontier flights from St. Louis to Denver

Find some of the cheapest Frontier flights traveling from St. Louis to Denver. It's recommended that users confirm their flight details before booking.

Cheap Delta flights from St. Louis to Denver

Have a look at some of the cheapest available Delta flights departing from St. Louis and landing in Denver. Make sure to examine the flight information before completing your reservation.

Cheap St. Louis to Denver flights in September & October 2023

The best prices found for STL to DEN flights for September, October
These are some of the most attractive deals on flights from St. Louis to Denver in 2023. More deals are always being added, so be sure to check back regularly.

St. Louis to Denver 2023 flight deals

Cheap flights to Denver from St. Louis found for this year
These are some of the most attractive deals on flights from St. Louis to Denver in 2023. More deals are always being added, so be sure to check back regularly.

Non-stop flights to Denver from St. Louis

Save time with St. Louis to Denver direct flight deals
Consider booking one of these non-stop flights heading from St. Louis to Denver. Select from other flights from St. Louis to Denver by using the search form above.

St. Louis to Denver flights leaving soon

Late deals on return flights to Denver from St. Louis, departing today and this week
Consider one of these great deals we found on last-minute flights from St. Louis to Denver. Users should examine the flight details to ensure there are no surprises.

One-way flights to Denver from St. Louis

The cheapest one-way flights from St. Louis to Denver
Users in need of a one-way flight from St. Louis to Denver can choose from these deals. Users can also find round-trip St. Louis to Denver flights by using the search form above.

Find flights from St. Louis to Denver within your budget

Use the slider to find flights from St. Louis to Denver that fit your budget.

Fly from

Any airport

Fly to

Any airport

Budget

$38 - $177

Route

Depart

Return

Price

Lambert-St LouisDenver Intl

STL - DEN

STLDEN

Lambert-St Louis

Wed 10/25

Nonstop2h 29m

Denver Intl

Sat 10/28

Nonstop2h 06m

Lambert-St LouisDenver Intl

STL - DEN

STLDEN

Lambert-St Louis

Wed 10/25

Nonstop2h 29m

Denver Intl

Wed 11/1

Nonstop2h 06m

Lambert-St LouisDenver Intl

STL - DEN

STLDEN

Lambert-St Louis

Thu 10/26

Nonstop2h 27m

Denver Intl

Sat 10/28

Nonstop2h 06m

Lambert-St LouisDenver Intl

STL - DEN

STLDEN

Lambert-St Louis

Wed 10/18

Nonstop2h 31m

Denver Intl

Sun 11/12

Nonstop2h 07m

Lambert-St LouisDenver Intl

STL - DEN

STLDEN

Lambert-St Louis

Wed 10/18

Nonstop2h 36m

Denver Intl

Thu 10/19

Nonstop2h 07m

Lambert-St LouisDenver Intl

STL - DEN

STLDEN

Lambert-St Louis

Wed 10/25

Nonstop2h 29m

Denver Intl

Sun 10/29

Nonstop2h 06m

Lambert-St LouisDenver Intl

STL - DEN

STLDEN

Lambert-St Louis

Tue 10/31

Nonstop2h 31m

Denver Intl

Mon 11/6

1 stop14h 06m

Lambert-St LouisDenver Intl

STL - DEN

STLDEN

Lambert-St Louis

Mon 10/16

1 stop16h 43m

Denver Intl

Wed 10/25

Nonstop2h 06m

Lambert-St LouisDenver Intl

STL - DEN

STLDEN

Lambert-St Louis

Sat 12/9

1 stop5h 20m

Denver Intl

Mon 12/11

1 stop7h 14m

Flights are sorted by cheapest first

Deals found on 9/27

Reviews of airlines servicing Denver

Read through reviews of airlines operating flights from St. Louis to Denver, such as Frontier, Delta and American Airlines. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.1
Very good
1,394 reviews

Food

7.2

Crew

8.6

Overall

8.1

Comfort

8.0

Entertainment

7.2

Boarding

8.3

Reviews

1 / 10

Really nothing. There was no food involved and I did not participate in any entertainment but the flight attendant who wins the gold star is Ralph on my flight from Portland to Sacramento! (7/24 take off at 6:15 am)

Alaska Airlines
8.1
Very good
1,394 reviews
Alaska Airlines
8.1
Very good
1,394 reviews

Food

7.2

Crew

8.6

Overall

8.1

Comfort

8.0

Entertainment

7.2

Boarding

8.3

Reviews

1 / 10

Really nothing. There was no food involved and I did not participate in any entertainment but the flight attendant who wins the gold star is Ralph on my flight from Portland to Sacramento! (7/24 take off at 6:15 am)

Delta
7.9
Good
3,023 reviews
Alaska Airlines
8.1
Very good
1,394 reviews

Food

7.2

Crew

8.6

Overall

8.1

Comfort

8.0

Entertainment

7.2

Boarding

8.3

Reviews

1 / 10

Really nothing. There was no food involved and I did not participate in any entertainment but the flight attendant who wins the gold star is Ralph on my flight from Portland to Sacramento! (7/24 take off at 6:15 am)

United Airlines
7.4
Good
1,890 reviews
Alaska Airlines
8.1
Very good
1,394 reviews

Food

7.2

Crew

8.6

Overall

8.1

Comfort

8.0

Entertainment

7.2

Boarding

8.3

Reviews

1 / 10

Really nothing. There was no food involved and I did not participate in any entertainment but the flight attendant who wins the gold star is Ralph on my flight from Portland to Sacramento! (7/24 take off at 6:15 am)

American Airlines
7.2
Good
2,635 reviews
Alaska Airlines
8.1
Very good
1,394 reviews

Food

7.2

Crew

8.6

Overall

8.1

Comfort

8.0

Entertainment

7.2

Boarding

8.3

Reviews

1 / 10

Really nothing. There was no food involved and I did not participate in any entertainment but the flight attendant who wins the gold star is Ralph on my flight from Portland to Sacramento! (7/24 take off at 6:15 am)

Spirit Airlines
6.3
Okay
1,483 reviews
Alaska Airlines
8.1
Very good
1,394 reviews

Food

7.2

Crew

8.6

Overall

8.1

Comfort

8.0

Entertainment

7.2

Boarding

8.3

Reviews

1 / 10

Really nothing. There was no food involved and I did not participate in any entertainment but the flight attendant who wins the gold star is Ralph on my flight from Portland to Sacramento! (7/24 take off at 6:15 am)

Related info for your journey

Useful info, stats and facts about St. Louis to Denver flights.

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 4 different airlines have flights from Lambert-St Louis (STL) to Denver Intl (DEN) on a regular basis. There are 18 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 23m.

Can I find flights from St. Louis to Denver for under $100 on Cheapflights?

Yes, there are multiple flights from St. Louis to Denver for under $100. The cheapest flight booked recently is on Frontier for just $38, but on average you can expect to pay $68.

Are there nonstop flights from St. Louis to Denver for under $100 on Cheapflights?

Cheapflights has at least 20 direct flights from St. Louis to Denver under $100. A good price for a nonstop flight from St. Louis to Denver is less than $74.

Are there last-minute flights available from St. Louis to Denver for under $100?

There are currently 20+ open flights from St. Louis to Denver within the next 7 days for less than $100.

What days are nonstop flights available from St. Louis to Denver?

Days when nonstop flights are available for this flight are: Thursday, Friday, Saturday.

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

How many flights depart from St. Louis to Denver on average per day?

23 flight departures from St. Louis to Denver per day on average.
Early Morning (Midnight to 6am) - 17% of flight departures
Morning (6am - Noon) - 30% of flight departures
Afternoon (Noon - 6pm) - 39% of flight departures
Evening (6pm - Midnight) - 13% of flight departures

How long is the flight from St. Louis to Denver?

Departing from St. Louis to Denver will take you 2h 29m. Airlines will cover a distance of 772 mi. Generally, flights for this route are nonstop.

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

Frontier, at $38, was found to be the cheapest airline from St. Louis to Denver.. Users have found that Frontier is 80% 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 $29 on Frontier. Other airlines that offer cheap prices include Spirit Airlines from $91 and Delta from $109 one-way.

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

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 Air Canada (80%), United Airlines (78%) or Frontier (67%) 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 $637, our data indicates the cheapest price to be $41. The most popular route (Lambert-St Louis - Denver Intl), is priced around $68.

What does STL to DEN mean?

Great question - STL to DEN just means Lambert-St Louis Airport to Denver Intl Airport. Now you’ll know what these unique codes when you look for flights!

Alternative routes for St. Louis to Denver

See prices for flight routes from nearby airports that may be better suited for you.

Top 4 airlines flying from St. Louis to Denver

The chart below displays the airlines Cheapflights users traveling from St. Louis to Denver choose most often. Cheapest and average prices are based on aggregated data from the past 12 months.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$48Average$120FlexibilityNo cancel feeOn-time62%
Search Frontier flights
United AirlinesCheapest$114Average$325FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
DeltaCheapest$185Average$394FlexibilityNo cancel feeOn-timeN/A
Search Delta flights
American AirlinesCheapest$236Average$403FlexibilityNo cancel feeOn-time71%
Search American Airlines flights

Hourly flight availability from St. Louis to Denver

See what time of day planes typically take off from St. Louis to Denver
22%of flight departuresEarly morningMidnight to 6 am
28%of flight departuresMorning6 am to noon
46%of flight departuresAfternoonNoon to 6 pm
4%of flight departuresEvening6 pm to midnight
Midnight
6 AM
Noon
6 PM

Weekly flight availability from St. Louis to Denver

See how many times per day planes take to the skies headed from St. Louis to Denver
Sunday13daily flights
Monday22daily flights
Tuesday20daily flights
Wednesday20daily flights
Thursday21daily flights
Friday21daily flights
Saturday12daily flights

Fly with Cheapflights

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How does Cheapflights help users find flights from St. Louis to Denver?

Deals for St. Louis to Denver flights are sourced from 900+ travel sites when you use Cheapflights. When all flight results come back, Cheapflights lets you sort and filter flights using different criteria to choose better, like price, airport, cabin class, and plenty of other options.

Why should you use Cheapflights to find cheap flight tickets from St. Louis to Denver?

It’s simple! Cheapflights, which is free to use for everyone, saves millions of users time and money every year by helping them find the cheapest and most suitable flights from St. Louis to Denver.

Can Cheapflights find flights from St. Louis to Denver with no change fees?

Users can book flights with no change fees policies with our dedicated filters. Book flights from St. Louis to Denver flexibly with Cheapflights today.

Can Cheapflights notify me if prices for flights from St. Louis to Denver become cheaper?

Yes! Start tracking prices for St. Louis to Denver flights today and get alerted whenever prices for these flights change. To access this feature, navigate to the search form above to perform a search, which will then prompt you for a valid email address to use the tool.

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