For a quick security experience at DEN, use the South checkpoint, which is open 24 hours. Reserve a time online for general screening.
$28+ 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 1/7. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — STL
Jan 17 — Jan 241
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
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 January or February, booked 74 days in advance, depart on a Friday or Wednesday and return on a Wednesday
Cheap 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 December 18, 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 December 18, 2025.
This Super.com deal was found by Cheapflights users on 12/15. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/316:50 amDEN - STL
Nonstop2h 12mFrontier
Wed 1/143:43 pmSTL - DEN
Nonstop2h 37mFrontier
Deal found 12/15![Frontier logo]()
$187
This Priceline deal was found by Cheapflights users on 12/17. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/1912:26 pmDEN - STL
1 stop6h 21mFrontier
Wed 1/77:43 pmSTL - DEN
Nonstop2h 32mFrontier
Deal found 12/17![Frontier logo]()
$210
This CheapOair deal was found by Cheapflights users on 12/15. 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.
Wed 12/316:50 amDEN - STL
Nonstop2h 12mFrontier
Tue 1/135:11 pmSTL - DEN
1 stop19h 12mFrontier
Deal found 12/15![Frontier logo]()
$228
This Expedia deal was found by Cheapflights users on 12/17. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/2810:37 pmDEN - STL
1 stop21h 48mFrontier
Fri 1/28:42 pmSTL - DEN
1 stop13h 13mFrontier
Deal found 12/17![Frontier logo]()
$233
This Expedia deal was found by Cheapflights users on 12/16. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/297:00 amDEN - STL
1 stop13h 25mFrontier
Thu 1/15:19 pmSTL - DEN
1 stop11h 39mFrontier
Deal found 12/16![Frontier logo]()
$234
This Kiwi.com deal was found by Cheapflights users on 12/15. 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 12/186:00 amDEN - STL
1 stop25h 12mFrontier
Mon 12/2210:10 pmSTL - DEN
1 stop6h 48mFrontier
Deal found 12/15![Frontier logo]()
$241
This CheapOair deal was found by Cheapflights users on 12/16. 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.
Thu 12/256:00 amDEN - STL
1 stop25h 12mFrontier
Wed 12/317:43 pmSTL - DEN
Nonstop2h 32mFrontier
Deal found 12/16![Frontier logo]()
$258
This Frontier deal was found by Cheapflights users on 12/16. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/316:50 amDEN - STL
Nonstop2h 12mFrontier
Sun 1/410:10 pmSTL - DEN
1 stop6h 48mFrontier
Deal found 12/16![Frontier logo]()
$261
Find 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 December 18, 2025.
Most accurate provider | eDreams 3 stars |
|---|---|
Most trusted provider | eDreams 3 stars |
Round-trip from | $104 (Cheapflightsfares) |
One-way from | $28 (Kiwi.com) |
Popular in | June |
Cheapest in | January |
Average price | $279 |
Good round-trip deal | $188 or less |
Good one-way deal | $73 or less |
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 December 18, 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
Sat 1/10
6:50 am-10:02 am
Nonstop2h 12m
Lambert-St Louis
Wed 1/14
5:11 pm-5:31 pm
1 stop25h 20m
$131
DenverSt. Louis
DEN - STL
DENSTL
Denver Intl
Sat 1/10
6:50 am-10:02 am
Nonstop2h 12m
Lambert-St Louis
Sun 1/11
12:37 pm-3:58 am
1 stop16h 21m
$141
DenverSt. Louis
DEN - STL
DENSTL
Denver Intl
Thu 1/8
6:00 am-2:48 pm
1 stop7h 48m
Lambert-St Louis
Mon 1/12
1:07 pm-11:19 pm
1 stop11h 12m
$162
DenverSt. Louis
DEN - STL
DENSTL
Denver Intl
Fri 1/16
3:26 pm-6:32 pm
Nonstop2h 06m
Lambert-St Louis
Sun 1/18
10:09 pm-8:25 pm
2 stops23h 16m
$171
DenverSt. Louis
DEN - STL
DENSTL
Denver Intl
Tue 1/27
3:19 pm-6:51 am
2 stops14h 32m
Lambert-St Louis
Wed 1/28
8:22 pm-12:19 pm
1 stop16h 57m
$179
DenverSt. Louis
DEN - STL
DENSTL
Denver Intl
Tue 1/13
11:30 am-6:51 am
2 stops18h 21m
Lambert-St Louis
Tue 1/20
5:42 pm-5:36 pm
1 stop24h 54m
$184
DenverSt. Louis
DEN - STL
DENSTL
Denver Intl
Wed 1/14
9:45 am-3:00 pm
1 stop4h 15m
Lambert-St Louis
Wed 1/21
7:55 pm-9:20 pm
Nonstop2h 25m
$187
DenverSt. Louis
DEN - STL
DENSTL
Denver Intl
Sat 1/24
10:10 am-1:16 pm
Nonstop2h 06m
Lambert-St Louis
Tue 1/27
4:15 pm-5:53 pm
Nonstop2h 38m
$214
DenverSt. Louis
DEN - STL
DENSTL
Denver Intl
Thu 1/22
10:10 am-1:16 pm
Nonstop2h 06m
Lambert-St Louis
Sat 1/24
8:45 am-10:21 am
Nonstop2h 36m
$225
DenverSt. Louis
DEN - STL
DENSTL
Denver Intl
Mon 3/30
6:35 am-9:49 am
Nonstop2h 14m
Lambert-St Louis
Thu 4/2
7:43 pm-9:15 pm
Nonstop2h 32m
$238
Showing 1-10 of 22 results
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 December.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy2 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*1 star | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy- | Trust Score*1 star | |
| Price Accuracy3 stars | Trust Score*2 stars |
- Most accurate provider: When it comes to deals on Denver-St. Louis flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Denver-St. Louis flight deals on Cheapflights vs. eDreams >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 eDreams the most. eDreams 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.
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 December 12, 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 74 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, February is the cheapest month in which you can book a flight from Denver to St. Louis (average of $37). Flying from Denver to St. Louis in July is currently the most expensive (average of $126). 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 December 18, 2025.
It’s optimal to fly from Denver to St. Louis in the morning. By choosing this option you can save up to 17% on the cost of your flight, compared to a flight in the afternoon.
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 December 13, 2025.
Travelers seeking maximum savings on their Denver to St. Louis flight should consider departing on Friday 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.
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 December 18, 2025.
Get a feel of what it's like to fly with Southwest, United Airlines, and Frontier from Denver to St. Louis by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Entertainment
7.5
Food
7.0
Crew
8.6
Boarding
8.1
Overall
7.9
Comfort
8.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Entertainment
7.5
Food
7.0
Crew
8.6
Boarding
8.1
Overall
7.9
Comfort
8.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Entertainment
7.5
Food
7.0
Crew
8.6
Boarding
8.1
Overall
7.9
Comfort
8.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Entertainment
7.5
Food
7.0
Crew
8.6
Boarding
8.1
Overall
7.9
Comfort
8.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
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.
Traveling to a place near St. Louis?
Book flights to St. Louis if you plan to visit one of these locationsEdwardsville
O'Fallon
Fairview Heights
Maryland Heights
Collinsville
Swansea
Eureka
Glencoe
St. Peters
Chesterfield
Alton
Farmington
Festus
Browse thousands of different options on Cheapflights for your next trip
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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.
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 December 18, 2025.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$54 | Average$162 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$158 | Average$325 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$177 | Average$301 | FlexibilityNo cancel fee | On-time63% |