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St. Louis

$64+ Cheap flights from Colorado to St. Louis (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 9/24. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — STL
Aug 26 — Sep 21
Wed 8/26
Wed 9/2
1 adult, Economy
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Cheap flight deals from Colorado to St. Louis

Cheapest flights from Colorado to St. Louis
Explore the most affordable flight options available from Colorado to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 27, 2026.

This Kiwi.com deal was found by Cheapflights users on 7/23. 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.
Mon 8/316:30 am
DEN
-
STL
1 stop9h 52m
Frontier
Sun 9/67:58 pm
STL
-
DEN
Nonstop2h 27m
Frontier
Deal found 7/23$166
This Kiwi.com deal was found by Cheapflights users on 7/23. 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.
Thu 9/36:30 am
DEN
-
STL
1 stop9h 52m
Frontier
Sun 9/67:58 pm
STL
-
DEN
Nonstop2h 27m
Frontier
Deal found 7/23$167
This Kiwi.com deal was found by Cheapflights users on 7/23. 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.
Fri 9/114:12 pm
DEN
-
STL
Nonstop2h 03m
Frontier
Sun 9/1310:35 am
STL
-
DEN
1 stop12h 58m
Frontier
Deal found 7/23$168
This Kiwi.com deal was found by Cheapflights users on 7/23. 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.
Thu 8/139:06 pm
DEN
-
STL
2 stops34h 51m
Frontier
Sat 8/158:08 pm
STL
-
DEN
Nonstop2h 36m
Frontier
Deal found 7/23$169
This eDestinos deal was found by Cheapflights users on 7/22. 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 eDestinos is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/129:06 pm
DEN
-
STL
2 stops19h 31m
Frontier
Sat 8/158:08 pm
STL
-
DEN
Nonstop2h 36m
Frontier
Deal found 7/22$170
This Kiwi.com deal was found by Cheapflights users on 7/23. 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 9/211:59 pm
DEN
-
STL
1 stop16h 23m
Frontier
Mon 9/76:17 pm
STL
-
DEN
1 stop16h 02m
Frontier
Deal found 7/23$171
This Kiwi.com deal was found by Cheapflights users on 7/23. 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.
Tue 9/110:09 am
DEN
-
STL
1 stop5h 22m
Frontier
Sun 9/67:58 pm
STL
-
DEN
Nonstop2h 27m
Frontier
Deal found 7/23$172
This Kiwi.com deal was found by Cheapflights users on 7/27. 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.
Thu 8/274:00 pm
DEN
-
STL
Nonstop2h 13m
Frontier
Sun 8/306:17 pm
STL
-
DEN
1 stop20h 44m
Frontier
Deal found 7/27$173
This Kiwi.com deal was found by Cheapflights users on 7/22. 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.
Fri 8/216:30 am
DEN
-
STL
1 stop9h 52m
Frontier
Fri 8/286:17 pm
STL
-
DEN
1 stop16h 02m
Frontier
Deal found 7/22$174
This Kiwi.com deal was found by Cheapflights users on 7/23. 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.
Fri 9/44:00 pm
DEN
-
STL
Nonstop2h 13m
Frontier
Sun 9/67:58 pm
STL
-
DEN
Nonstop2h 27m
Frontier
Deal found 7/23$175
This Kiwi.com deal was found by Cheapflights users on 7/22. 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.
Thu 8/276:30 am
DEN
-
STL
1 stop9h 52m
Frontier
Thu 8/277:58 pm
STL
-
DEN
Nonstop2h 27m
Frontier
Deal found 7/22$176
This Kiwi.com deal was found by Cheapflights users on 7/25. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/314:00 pm
DEN
-
STL
Nonstop2h 13m
Frontier
Thu 9/36:17 pm
STL
-
DEN
1 stop20h 44m
Frontier
Deal found 7/25$178

Find flight deals from Colorado to St. Louis

Keep the following information in mind while searching for Colorado to St. Louis flight deals. Data was last updated July 27, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$166
(Kiwi.com)

One-way from

$64
(Frontier)

Popular in

June

Cheapest in

January

Average price

$328

Good round-trip deal

$274 or less

Good one-way deal

$122 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 Colorado to Lambert-St Louis
Search Deals
One-way flight from Colorado to Lambert-St Louis
Search Deals
Highest demand for flights based on searches. 16% potential increase in price ($52 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($6 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in July 2026
Search Deals
Price to beat on a round-trip flight from Colorado to Lambert-St Louis.
Search Deals
Price to beat on a one-way flight from Colorado to Lambert-St Louis.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Colorado 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 July 27, 2026.
Use the filters below to find and compare flights from Colorado to St. Louis that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Wed 9/2

8:35 am-11:40 am

Nonstop2h 05m

Lambert-St Louis

Mon 9/7

8:40 pm-10:00 pm

Nonstop2h 20m

$187

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Mon 8/31

5:35 pm-8:46 pm

Nonstop2h 11m

Lambert-St Louis

Sat 9/5

4:40 pm-6:10 pm

Nonstop2h 30m

$187

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Thu 10/1

5:50 am-8:50 am

Nonstop2h 00m

Lambert-St Louis

Thu 10/1

9:50 pm-11:10 pm

Nonstop2h 20m

$187
Quickest round-trip

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Thu 9/3

7:00 am-10:00 am

Nonstop2h 00m

Lambert-St Louis

Sun 9/6

1:25 pm-2:40 pm

Nonstop2h 15m

$192

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Mon 8/31

8:05 pm-11:10 pm

Nonstop2h 05m

Lambert-St Louis

Sat 9/5

4:20 pm-9:20 pm

1 stop6h 00m

$197

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Wed 8/12

8:40 am-12:55 pm

1 stop3h 15m

Lambert-St Louis

Sat 8/15

2:25 pm-6:40 pm

1 stop5h 15m

$207

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Mon 8/24

3:15 pm-10:05 pm

2 stops5h 50m

Lambert-St Louis

Mon 8/31

8:30 am-11:00 am

1 stop3h 30m

$262

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Sat 10/24

8:28 pm-11:44 pm

Nonstop2h 16m

Lambert-St Louis

Sat 11/7

1:40 pm-3:09 pm

Nonstop2h 29m

$267

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Thu 12/10

1:30 pm-4:26 pm

Nonstop1h 56m

Lambert-St Louis

Mon 12/14

9:13 am-10:35 am

Nonstop2h 22m

$267

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Fri 9/4

8:25 pm-11:40 pm

Nonstop2h 15m

Lambert-St Louis

Sat 9/5

4:40 pm-6:10 pm

Nonstop2h 30m

$282

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/25

Showing 1-10 of 60 resultsSorted by cheapest first
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Best time to book a flight from Colorado to St. Louis

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

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

Currently, January is the cheapest month in which you can book a flight from Colorado to St. Louis (average of $182). Flying from Colorado to St. Louis in June is currently the most expensive (average of $359). 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 CO to STL?

Find hourly flight availability from Colorado 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 July 27, 2026.

It’s optimal to fly from Colorado to St. Louis in the afternoon. By choosing this option you can save up to 18% on the cost of your flight, compared to a flight at noon.

Weekly flight availability from Colorado to St. Louis

Explore weekly flight availability from Colorado to St. Louis. 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 July 27, 2026.

The most flights from USCO to STL are scheduled on a Sunday (19 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (8 on average).

How much does it cost to fly round-trip from Colorado to St. Louis?

Airfare is typical for this route at the moment.
Colorado to St. Louis flights typically cost between $124 and $299 in August.
The cheapest round-trip price found within the last 5 days was $166 on Frontier (Aug 31-Sep 6).

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

The best time to book flights from Colorado to St. Louis is 50 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

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

Use this chart to determine the cheapest time to fly round-trip from Colorado to St. Louis. Price data was last updated on July 25, 2026.

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

Related info for your journey

Find useful and relevant information for your journey from Colorado 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 airport do you fly into for flights to St. Louis from Colorado?

    For a flight from Colorado to St. Louis, you will be flying into Lambert-St Louis. Lambert-St Louis (STL) is just 12.7 mi from the center of the city.

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

    This flight path from Colorado to Lambert-St Louis was viewed by 32 users in the past month. Keep an eye out for changes in search interest prior to high and low season.

  • How long is the flight from Colorado to St. Louis?

    Departing from Colorado to St. Louis will take you 2h 05m. Colorado and St. Louis are separated by a distance of 767 mi. Both multi-stop and nonstop flights can be found to your destination and back.

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

    The cheapest airlines for a one-way flight from Colorado to St. Louis are Frontier ($30), United Airlines ($98), and Southwest ($102).

  • What are the most popular routes from Colorado to St. Louis?

    When deciding which route to take from Colorado to St. Louis consider Denver Intl - Lambert-St Louis, Colorado Springs - Lambert-St Louis or Durango La Plata County - Lambert-St Louis as they are the most popular.

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

    The top 3 most reliable airlines when flying from Colorado to St. Louis are Air Canada (72%), United Airlines (69%) and Frontier (65%).

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

    Looking for the cheapest flight from Colorado to St. Louis? While on average our users pay $292, our data indicates the cheapest price to be $55. The most popular route (Denver Intl - Lambert-St Louis), is priced around $148.

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

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

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

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

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

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

    Currently, January is the cheapest month in which you can book a flight from Colorado to St. Louis (average of $182). Flying from Colorado to St. Louis in June is currently the most expensive (average of $359). 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
Edwardsville
O'Fallon
Fenton
Swansea
Fairview Heights
Eureka
Maryland Heights
Collinsville
Wentzville
Glencoe
Chesterfield
Farmington

Browse thousands of different options on Cheapflights for your next trip

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Alternative routes for Colorado to St. Louis

See prices for flight routes from nearby airports that may be better suited for you.
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Top 4 airlines flying from Colorado to St. Louis

Discover the top 4 airlines that operate flights from Colorado 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 July 27, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$58Average$193FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$189Average$395FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$197Average$388FlexibilityNo cancel feeOn-time63%
American AirlinesCheapest$248Average$388FlexibilityNo cancel feeOn-time71%

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