$43+ 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 4/3. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — STL
Apr 17 — Apr 241
Round-trip
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 August, booked 71 days in advance, depart on a Friday or Saturday and return on a Wednesday
Cheap flight deals from Denver to St. Louis
Cheapest
Best
Last-minute
One-way
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 March 18, 2026.
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 March 18, 2026.
This Cheapflightsfares deal was found by Cheapflights users on 3/15. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/66:40 am
DEN
- STL
Nonstop2h 08m
Frontier
Wed 4/88:16 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/15![Frontier logo]()
$105
This Frontier deal was found by Cheapflights users on 3/14. 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 4/86:40 am
DEN
- STL
Nonstop2h 08m
Frontier
Fri 4/108:16 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/14![Frontier logo]()
$106
This Frontier deal was found by Cheapflights users on 3/14. 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 4/86:40 am
DEN
- STL
Nonstop2h 08m
Frontier
Wed 4/88:16 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/14![Frontier logo]()
$112
This Priceline deal was found by Cheapflights users on 3/17. 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.
Sun 4/264:09 pm
DEN
- STL
Nonstop2h 12m
Frontier
Mon 4/278:17 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/17![Frontier logo]()
$118
This Frontier deal was found by Cheapflights users on 3/13. 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.
Fri 5/14:09 pm
DEN
- STL
Nonstop2h 12m
Frontier
Mon 5/48:17 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/13![Frontier logo]()
$120
This Cheapflightsfares deal was found by Cheapflights users on 3/17. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/106:40 am
DEN
- STL
Nonstop2h 08m
Frontier
Mon 4/138:19 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/17![Frontier logo]()
$121
This Cheapflightsfares deal was found by Cheapflights users on 3/17. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/16:40 am
DEN
- STL
Nonstop2h 08m
Frontier
Wed 4/88:16 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/17![Frontier logo]()
$127
This Frontier deal was found by Cheapflights users on 3/15. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/14:15 pm
DEN
- STL
Nonstop2h 08m
Frontier
Wed 6/38:08 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/15![Frontier logo]()
$130
This Cheapflightsfares deal was found by Cheapflights users on 3/17. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/164:09 pm
DEN
- STL
Nonstop2h 12m
Frontier
Thu 4/238:06 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/17![Frontier logo]()
$131
Best flights from Denver to St. LouisDiscover 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 March 18, 2026.
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 March 18, 2026.
This Southwest deal was found by Cheapflights users on 3/12. 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.
Mon 4/204:45 pm
DEN
- STL
1 stop4h 55m
Southwest
Sat 4/255:40 am
STL
- DEN
2 stops7h 10m
Southwest
Deal found 3/12![Southwest logo]()
$234
This Delta deal was found by Cheapflights users on 3/14. 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.
Sat 4/44:27 pm
DEN
- STL
1 stop6h 31m
Delta
Wed 4/86:59 pm
STL
- DEN
1 stop6h 10m
Delta
Deal found 3/14![Delta logo]()
$261
This United Airlines deal was found by Cheapflights users on 3/12. 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 Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/248:45 pm
DEN
- STL
Nonstop2h 12m
United Airlines
Wed 7/295:41 pm
STL
- DEN
1 stop5h 18m
United Airlines
Deal found 3/12![United Airlines logo]()
$357
This Southwest deal was found by Cheapflights users on 3/13. 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.
Sat 4/187:15 am
DEN
- STL
2 stops7h 05m
Southwest
Sat 4/256:10 am
STL
- DEN
2 stops7h 05m
Southwest
Deal found 3/13![Southwest logo]()
$243
This Delta deal was found by Cheapflights users on 3/16. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/96:12 pm
DEN
- STL
1 stop4h 13m
Delta
Mon 4/132:20 pm
STL
- DEN
1 stop7h 26m
Delta
Deal found 3/16![Delta logo]()
$261
This Southwest deal was found by Cheapflights users on 3/17. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/87:35 am
DEN
- STL
Nonstop2h 05m
Southwest
Fri 5/86:45 pm
STL
- DEN
Nonstop2h 20m
Southwest
Deal found 3/17![Southwest logo]()
$257
This Delta deal was found by Cheapflights users on 3/16. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/96:12 pm
DEN
- STL
1 stop4h 13m
Delta
Sat 4/116:00 am
STL
- DEN
1 stop6h 55m
Delta
Deal found 3/16![Delta logo]()
$261
This Southwest deal was found by Cheapflights users on 3/16. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/246:20 am
DEN
- STL
Nonstop2h 05m
Southwest
Sun 4/269:55 pm
STL
- DEN
Nonstop2h 20m
Southwest
Deal found 3/16![Southwest logo]()
$257
This Delta deal was found by Cheapflights users on 3/12. 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 6/36:19 pm
DEN
- STL
1 stop5h 11m
Delta
Sat 6/67:05 pm
STL
- DEN
1 stop6h 28m
Delta
Deal found 3/12![Delta logo]()
$316
This Delta deal was found by Cheapflights users on 3/16. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/1012:35 am
DEN
- STL
1 stop8h 11m
Delta
Sat 4/113:05 pm
STL
- DEN
1 stop5h 46m
Delta
Deal found 3/16![Delta logo]()
$320
This Southwest deal was found by Cheapflights users on 3/15. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/2210:20 am
DEN
- STL
Nonstop2h 10m
Southwest
Sun 7/269:45 pm
STL
- DEN
Nonstop2h 20m
Southwest
Deal found 3/15![Southwest logo]()
$357
Last-minute flights from Denver to St. LouisDiscover last-minute flight deals from Denver to St. Louis. Data last updated March 18, 2026 and is based on user searches.
Discover last-minute flight deals from Denver to St. Louis. Data last updated March 18, 2026 and is based on user searches.
This Cheapflightsfares deal was found by Cheapflights users on 3/17. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/16:40 am
DEN
- STL
Nonstop2h 08m
Frontier
Wed 4/88:16 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/17![Frontier logo]()
$127
This Cheapflightsfares deal was found by Cheapflights users on 3/15. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/66:40 am
DEN
- STL
Nonstop2h 08m
Frontier
Wed 4/88:16 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/15![Frontier logo]()
$105
This Frontier deal was found by Cheapflights users on 3/14. 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 4/86:40 am
DEN
- STL
Nonstop2h 08m
Frontier
Fri 4/108:16 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/14![Frontier logo]()
$106
This Frontier deal was found by Cheapflights users on 3/14. 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 4/86:40 am
DEN
- STL
Nonstop2h 08m
Frontier
Wed 4/88:16 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/14![Frontier logo]()
$112
This Cheapflightsfares deal was found by Cheapflights users on 3/17. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/106:40 am
DEN
- STL
Nonstop2h 08m
Frontier
Mon 4/138:19 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/17![Frontier logo]()
$121
This Super.com deal was found by Cheapflights users on 3/17. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/136:40 am
DEN
- STL
Nonstop2h 08m
Frontier
Sat 4/184:16 pm
STL
- DEN
1 stop9h 03m
Frontier
Deal found 3/17![Frontier logo]()
$134
This Cheapflightsfares deal was found by Cheapflights users on 3/17. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/164:09 pm
DEN
- STL
Nonstop2h 12m
Frontier
Thu 4/238:06 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/17![Frontier logo]()
$131
This Priceline deal was found by Cheapflights users on 3/17. 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.
Sun 4/264:09 pm
DEN
- STL
Nonstop2h 12m
Frontier
Mon 4/278:17 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/17![Frontier logo]()
$118
This Kiwi.com deal was found by Cheapflights users on 3/17. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/304:09 pm
DEN
- STL
Nonstop2h 12m
Frontier
Mon 5/48:17 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/17![Frontier logo]()
$111
One-way flights from Denver to St. LouisSearch for one-way flight options from Denver to St. Louis. Find affordable one-way fares based on user searches. Data last updated March 18, 2026.
Search for one-way flight options from Denver to St. Louis. Find affordable one-way fares based on user searches. Data last updated March 18, 2026.
This Kiwi.com deal was found by Cheapflights users on 3/17. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/36:40 am
DEN
- STL
Nonstop2h 08m
Frontier
Deal found 3/17![Frontier logo]()
$43
This Super.com deal was found by Cheapflights users on 3/17. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/174:09 pm
DEN
- STL
Nonstop2h 12m
Frontier
Deal found 3/17![Frontier logo]()
$44
This Frontier deal was found by Cheapflights users on 3/13. 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.
Mon 5/114:15 pm
DEN
- STL
Nonstop2h 08m
Frontier
Deal found 3/13![Frontier logo]()
$46
This Kiwi.com deal was found by Cheapflights users on 3/16. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/46:40 am
DEN
- STL
Nonstop2h 08m
Frontier
Deal found 3/16![Frontier logo]()
$49
This Frontier deal was found by Cheapflights users on 3/14. 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.
Mon 4/136:40 am
DEN
- STL
Nonstop2h 08m
Frontier
Deal found 3/14![Frontier logo]()
$50
This Kiwi.com deal was found by Cheapflights users on 3/18. 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.
Sat 4/184:20 pm
DEN
- STL
Nonstop2h 12m
Frontier
Deal found 3/18![Frontier logo]()
$52
This Cheapflightsfares deal was found by Cheapflights users on 3/13. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/84:00 pm
DEN
- STL
Nonstop2h 12m
Frontier
Deal found 3/13![Frontier logo]()
$54
This Super.com deal was found by Cheapflights users on 3/14. 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.
Thu 5/74:15 pm
DEN
- STL
Nonstop2h 08m
Frontier
Deal found 3/14![Frontier logo]()
$55
This Priceline deal was found by Cheapflights users on 3/17. 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.
Thu 4/164:09 pm
DEN
- STL
Nonstop2h 12m
Frontier
Deal found 3/17![Frontier logo]()
$56
This Frontier deal was found by Cheapflights users on 3/13. 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.
Sun 5/104:15 pm
DEN
- STL
Nonstop2h 08m
Frontier
Deal found 3/13![Frontier logo]()
$64
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 March 18, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $105 (Cheapflightsfares) |
One-way from | $43 (Kiwi.com) |
Popular in | June |
Cheapest in | January |
Average price | $299 |
Good round-trip deal | $195 or less |
Good one-way deal | $162 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 March 18, 2026.
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
Cheapest round-trip
DenverSt. Louis
DEN - STL
DENSTL
Denver Intl
Mon 4/20
4:45 pm-10:40 pm
1 stop4h 55m
Lambert-St Louis
Sat 4/25
5:40 am-11:50 am
2 stops7h 10m
$234
DenverSt. Louis
DEN - STL
DENSTL
Denver Intl
Sat 4/18
7:15 am-3:20 pm
2 stops7h 05m
Lambert-St Louis
Sat 4/25
6:10 am-12:15 pm
2 stops7h 05m
$243
Quickest round-trip
DenverSt. Louis
DEN - STL
DENSTL
Denver Intl
Fri 5/8
7:35 am-10:40 am
Nonstop2h 05m
Lambert-St Louis
Fri 5/8
6:45 pm-8:05 pm
Nonstop2h 20m
$257
DenverSt. Louis
DEN - STL
DENSTL
Denver Intl
Fri 4/24
6:20 am-9:25 am
Nonstop2h 05m
Lambert-St Louis
Sun 4/26
9:55 pm-11:15 pm
Nonstop2h 20m
$257
DenverSt. Louis
DEN - STL
DENSTL
Denver Intl
Sat 4/4
4:27 pm-11:58 pm
1 stop6h 31m
Lambert-St Louis
Wed 4/8
6:59 pm-12:09 am
1 stop6h 10m
$261
DenverSt. Louis
DEN - STL
DENSTL
Denver Intl
Thu 4/9
6:12 pm-11:25 pm
1 stop4h 13m
Lambert-St Louis
Mon 4/13
2:20 pm-8:46 pm
1 stop7h 26m
$261
DenverSt. Louis
DEN - STL
DENSTL
Denver Intl
Thu 4/9
6:12 pm-11:25 pm
1 stop4h 13m
Lambert-St Louis
Sat 4/11
6:00 am-11:55 am
1 stop6h 55m
$261
DenverSt. Louis
DEN - STL
DENSTL
Denver Intl
Wed 6/3
6:19 pm-12:30 am
1 stop5h 11m
Lambert-St Louis
Sat 6/6
7:05 pm-12:33 am
1 stop6h 28m
$316
DenverSt. Louis
DEN - STL
DENSTL
Denver Intl
Fri 4/10
12:35 am-9:46 am
1 stop8h 11m
Lambert-St Louis
Sat 4/11
3:05 pm-7:51 pm
1 stop5h 46m
$320
DenverSt. Louis
DEN - STL
DENSTL
Denver Intl
Fri 7/24
8:45 pm-11:57 pm
Nonstop2h 12m
Lambert-St Louis
Wed 7/29
5:41 pm-9:59 pm
1 stop5h 18m
$357
Showing 1-10 of 22 resultsSorted by cheapest first
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 March.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy- | Trust Score*1 star | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy1 star | Trust Score*2 stars |
- Most accurate provider: When it comes to deals on Denver-St. Louis flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Denver-St. Louis flight deals on Cheapflights vs. FlightHub >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 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 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.
DEN-STL
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
Prices
Airlines
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 March 13, 2026.
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 71 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 $55). Flying from Denver to St. Louis in June is currently the most expensive (average of $135). 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 March 18, 2026.
It’s optimal to fly from Denver to St. Louis in the morning. By choosing this option you can save up to 11% on the cost of your flight, compared to a flight at noon.
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 14, 2026.
Travelers seeking maximum savings on their Denver to St. Louis flight should consider departing on Saturday afternoons 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.
The best insider tips for Denver to St. Louis flights
AI-powered summary based on content written by travel experts. AI can make mistakes.
Cheapflights partnered with top experts to bring you the best recommendations for your Denver to St. Louis trip
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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 March 18, 2026.
Get a feel of what it's like to fly with Southwest,United Airlines, andFrontier 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
Boarding
8.1
Overall
8.0
Crew
8.6
Food
7.0
Comfort
8.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
Entertainment
7.5
Boarding
8.1
Overall
8.0
Crew
8.6
Food
7.0
Comfort
8.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
Entertainment
7.5
Boarding
8.1
Overall
8.0
Crew
8.6
Food
7.0
Comfort
8.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
Entertainment
7.5
Boarding
8.1
Overall
8.0
Crew
8.6
Food
7.0
Comfort
8.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
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
Fenton
Swansea
Fairview Heights
Maryland Heights
Collinsville
Eureka
Wentzville
Glencoe
Chesterfield
Alton
Farmington
Festus
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Denver and St. Louis flights
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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 March 18, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$58 | Average$167 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$167 | Average$313 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$177 | Average$317 | FlexibilityNo cancel fee | On-time63% |