$44+ Cheap flights from Denver to St. Louis (DEN - STL)
This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 11/11. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — STL
Oct 17 — Oct 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 October, booked 51 days in advance, depart on a Saturday or Friday and return on a Saturday
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 September 17, 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 September 17, 2026.
This Cheapflightsfares deal was found by Cheapflights users on 9/12. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/24:12 pm -
Nonstop2h 05m
Mon 10/58:10 pm -
Nonstop2h 29m
Deal found 9/12![Frontier logo]()
$122
This Kiwi.com deal was found by Cheapflights users on 9/14. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/276:31 pm -
1 stop22h 09m
Fri 10/306:44 pm -
1 stop14h 38m
Deal found 9/14![Frontier logo]()
$136
This Kiwi.com deal was found by Cheapflights users on 9/12. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/206:57 pm -
1 stop21h 43m
Mon 10/266:35 pm -
1 stop14h 47m
Deal found 9/12![Frontier logo]()
$140
This Priceline deal was found by Cheapflights users on 9/12. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/410:43 am -
1 stop5h 57m
Sat 11/77:59 pm -
Nonstop2h 31m
Deal found 9/12![Frontier logo]()
$145
This Priceline deal was found by Cheapflights users on 9/15. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/34:12 pm -
Nonstop2h 05m
Sat 10/107:42 pm -
Nonstop2h 27m
Deal found 9/15![Frontier logo]()
$152
This Cheapflightsfares deal was found by Cheapflights users on 9/12. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/194:12 pm -
Nonstop2h 03m
Fri 10/238:00 pm -
Nonstop2h 39m
Deal found 9/12![Frontier logo]()
$153
This Priceline deal was found by Cheapflights users on 9/13. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/74:09 pm -
Nonstop2h 05m
Mon 11/97:59 pm -
Nonstop2h 31m
Deal found 9/13![Frontier logo]()
$154
This Kiwi.com deal was found by Cheapflights users on 9/15. 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.
Sat 10/173:54 pm -
Nonstop2h 03m
Mon 10/196:35 pm -
1 stop14h 31m
Deal found 9/15![Frontier logo]()
$155
This Kiwi.com deal was found by Cheapflights users on 9/15. 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.
Wed 11/1110:43 am -
1 stop5h 57m
Sat 11/147:59 pm -
Nonstop2h 31m
Deal found 9/15![Frontier logo]()
$158
This Frontier deal was found by Cheapflights users on 9/12. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/164:12 pm -
Nonstop2h 03m
Sat 10/247:42 pm -
Nonstop2h 27m
Deal found 9/12![Frontier logo]()
$160
This Mytrip deal was found by Cheapflights users on 9/16. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/314:09 pm -
Nonstop2h 05m
Mon 11/26:44 pm -
2 stops18h 36m
Deal found 9/16![Frontier logo]()
$163
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 September 17, 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 September 17, 2026.
This Southwest deal was found by Cheapflights users on 9/16. 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.
Thu 10/158:45 pm -
Nonstop2h 05m
Mon 10/199:50 pm -
Nonstop2h 25m
Deal found 9/16![Southwest logo]()
$279
This United Airlines deal was found by Cheapflights users on 9/15. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/301:55 pm -
Nonstop2h 05m
Fri 1/16:58 pm -
1 stop5h 22m
Deal found 9/15![United Airlines logo]()
$283
This Southwest deal was found by Cheapflights users on 9/13. 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.
Thu 10/228:45 pm -
Nonstop2h 05m
Mon 10/266:05 am -
Nonstop2h 20m
Deal found 9/13![Southwest logo]()
$301
This United Airlines deal was found by Cheapflights users on 9/16. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/178:28 pm -
Nonstop2h 16m
Sun 10/258:50 am -
Nonstop2h 31m
Deal found 9/16![United Airlines logo]()
$333
This Southwest deal was found by Cheapflights users on 9/15. 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.
Thu 11/127:20 pm -
Nonstop2h 05m
Sun 11/154:50 pm -
Nonstop2h 25m
Deal found 9/15![Southwest logo]()
$359
This United Airlines deal was found by Cheapflights users on 9/15. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/125:52 pm -
Nonstop2h 07m
Mon 11/161:40 pm -
Nonstop2h 29m
Deal found 9/15![United Airlines logo]()
$381
This Southwest deal was found by Cheapflights users on 9/16. 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 10/237:10 am -
Nonstop2h 00m
Sun 10/258:30 am -
Nonstop2h 20m
Deal found 9/16![Southwest logo]()
$367
This United Airlines deal was found by Cheapflights users on 9/16. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/305:52 pm -
Nonstop2h 07m
Tue 11/31:08 pm -
1 stop6h 05m
Deal found 9/16![United Airlines logo]()
$384
This Southwest deal was found by Cheapflights users on 9/14. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/15:50 am -
Nonstop2h 00m
Mon 10/56:40 pm -
Nonstop2h 20m
Deal found 9/14![Southwest logo]()
$389
This United Airlines deal was found by Cheapflights users on 9/12. 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.
Sun 10/115:30 pm -
Nonstop2h 06m
Wed 10/141:36 pm -
Nonstop2h 24m
Deal found 9/12![United Airlines logo]()
$407
This Southwest deal was found by Cheapflights users on 9/13. 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.
Tue 10/131:30 pm -
1 stop3h 15m
Tue 10/208:30 am -
1 stop5h 20m
Deal found 9/13![Southwest logo]()
$412
Last-minute flights from Denver to St. LouisDiscover last-minute flight deals from Denver to St. Louis. Data last updated September 17, 2026 and is based on user searches.
Discover last-minute flight deals from Denver to St. Louis. Data last updated September 17, 2026 and is based on user searches.
This Cheapflightsfares deal was found by Cheapflights users on 9/12. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/24:12 pm -
Nonstop2h 05m
Mon 10/58:10 pm -
Nonstop2h 29m
Deal found 9/12![Frontier logo]()
$122
This Priceline deal was found by Cheapflights users on 9/15. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/34:12 pm -
Nonstop2h 05m
Sat 10/107:42 pm -
Nonstop2h 27m
Deal found 9/15![Frontier logo]()
$152
This Cheapflightsfares deal was found by Cheapflights users on 9/12. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/37:12 pm -
1 stop20h 22m
Mon 10/58:10 pm -
Nonstop2h 29m
Deal found 9/12![Frontier logo]()
$167
This Frontier deal was found by Cheapflights users on 9/12. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/164:12 pm -
Nonstop2h 03m
Sat 10/247:42 pm -
Nonstop2h 27m
Deal found 9/12![Frontier logo]()
$160
This Frontier deal was found by Cheapflights users on 9/12. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/164:12 pm -
Nonstop2h 03m
Fri 10/238:00 pm -
Nonstop2h 39m
Deal found 9/12![Frontier logo]()
$165
This Kiwi.com deal was found by Cheapflights users on 9/15. 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.
Sat 10/173:54 pm -
Nonstop2h 03m
Mon 10/196:35 pm -
1 stop14h 31m
Deal found 9/15![Frontier logo]()
$155
This Cheapflightsfares deal was found by Cheapflights users on 9/12. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/194:12 pm -
Nonstop2h 03m
Fri 10/238:00 pm -
Nonstop2h 39m
Deal found 9/12![Frontier logo]()
$153
This Kiwi.com deal was found by Cheapflights users on 9/12. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/206:57 pm -
1 stop21h 43m
Mon 10/266:35 pm -
1 stop14h 47m
Deal found 9/12![Frontier logo]()
$140
This Kiwi.com deal was found by Cheapflights users on 9/12. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/206:57 pm -
1 stop21h 43m
Sat 10/247:42 pm -
Nonstop2h 27m
Deal found 9/12![Frontier logo]()
$176
This Kiwi.com deal was found by Cheapflights users on 9/14. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/276:31 pm -
1 stop22h 09m
Fri 10/306:44 pm -
1 stop14h 38m
Deal found 9/14![Frontier logo]()
$136
This Mytrip deal was found by Cheapflights users on 9/16. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/314:09 pm -
Nonstop2h 05m
Mon 11/26:44 pm -
2 stops18h 36m
Deal found 9/16![Frontier logo]()
$163
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 September 17, 2026.
Search for one-way flight options from Denver to St. Louis. Find affordable one-way fares based on user searches. Data last updated September 17, 2026.
This Super.com deal was found by Cheapflights users on 9/12. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/1112:21 pm -
Nonstop2h 02m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/12![Frontier logo]()
$44
This Kiwi.com deal was found by Cheapflights users on 9/12. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/143:50 pm -
Nonstop2h 04m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/12![Frontier logo]()
$54
This Super.com deal was found by Cheapflights users on 9/12. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/113:50 pm -
Nonstop2h 04m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/12![Frontier logo]()
$60
This Super.com deal was found by Cheapflights users on 9/13. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/2110:38 am -
1 stop6h 02m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/13![Frontier logo]()
$67
This FlightHub deal was found by Cheapflights users on 9/14. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/16:24 pm -
1 stop11h 45m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/14![Frontier logo]()
$68
This Kiwi.com deal was found by Cheapflights users on 9/14. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/276:31 pm -
1 stop22h 09m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/14![Frontier logo]()
$72
This Kiwi.com deal was found by Cheapflights users on 9/15. 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.
Tue 11/176:31 pm -
1 stop22h 09m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/15![Frontier logo]()
$73
This Super.com deal was found by Cheapflights users on 9/15. 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 10/1412:21 pm -
Nonstop2h 03m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/15![Frontier logo]()
$78
This Super.com deal was found by Cheapflights users on 9/16. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/243:54 pm -
Nonstop2h 03m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/16![Frontier logo]()
$79
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 September 17, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $122 (Cheapflightsfares) |
One-way from | $44 (Super.com) |
Popular in | June |
Cheapest in | January |
Average price | $285 |
Good round-trip deal | $217 or less |
Good one-way deal | $124 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 7,457,451 searches. Data last updated September 17, 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 Denver Intl - STL Lambert-St Louis
DENSTL
Denver Intl
Fri 12/11
10:34 am-12:12 am
1 stop12h 38m
Lambert-St Louis
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$126
DenverSt. Louis
DEN Denver Intl - STL Lambert-St Louis
DENSTL
Denver Intl
Tue 10/13
8:10 pm-11:15 pm
Nonstop2h 05m
Lambert-St Louis
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$126
DenverSt. Louis
DEN Denver Intl - STL Lambert-St Louis
DENSTL
Denver Intl
Sat 11/14
7:05 am-1:23 pm
1 stop5h 18m
Lambert-St Louis
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$135
DenverSt. Louis
DEN Denver Intl - STL Lambert-St Louis
DENSTL
Denver Intl
Thu 11/26
6:05 am-9:05 am
Nonstop2h 00m
Lambert-St Louis
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$151
DenverSt. Louis
DEN Denver Intl - STL Lambert-St Louis
DENSTL
Denver Intl
Mon 10/12
8:28 pm-11:44 pm
Nonstop2h 16m
Lambert-St Louis
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$152
DenverSt. Louis
DEN Denver Intl - STL Lambert-St Louis
DENSTL
Denver Intl
Tue 10/20
7:00 am-1:20 pm
1 stop5h 20m
Lambert-St Louis
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$158
DenverSt. Louis
DEN Denver Intl - STL Lambert-St Louis
DENSTL
Denver Intl
Tue 10/20
5:30 pm-8:36 pm
Nonstop2h 06m
Lambert-St Louis
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$162
DenverSt. Louis
DEN Denver Intl - STL Lambert-St Louis
DENSTL
Denver Intl
Wed 10/14
8:28 pm-11:44 pm
Nonstop2h 16m
Lambert-St Louis
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$162
DenverSt. Louis
DEN Denver Intl - STL Lambert-St Louis
DENSTL
Denver Intl
Tue 11/17
1:55 pm-4:57 pm
Nonstop2h 02m
Lambert-St Louis
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$165
DenverSt. Louis
DEN Denver Intl - STL Lambert-St Louis
DENSTL
Denver Intl
Fri 10/9
8:45 pm-11:50 pm
Nonstop2h 05m
Lambert-St Louis
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$170
Showing 1-10 of 23 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 September.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy2 stars | Trust Score*3 stars | |
| Price Accuracy- | Trust Score*1 star | |
| Price Accuracy- | Trust Score*3 stars | |
| Price Accuracy2 stars | Trust Score*1 star |
- 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?
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 50 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, January is the cheapest month in which you can book a flight from Denver to St. Louis (average of $175). Flying from Denver to St. Louis in June is currently the most expensive (average of $337). 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 September 17, 2026.
It’s optimal to fly from Denver to St. Louis in the afternoon. By choosing this option you can save up to 20% on the cost of your flight, compared to a flight in the morning.
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 September 12, 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 at noon 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 September 17, 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.
Boarding
8.1
Entertainment
7.5
Food
7.0
Crew
8.6
Overall
8.0
Comfort
8.0
Reviews
1 / 20
10.0
ExcellentCourtney,Sep 2026
DEN - STL
Boarding
8.1
Entertainment
7.5
Food
7.0
Crew
8.6
Overall
8.0
Comfort
8.0
Reviews
1 / 20
10.0
ExcellentCourtney,Sep 2026
DEN - STL
Boarding
8.1
Entertainment
7.5
Food
7.0
Crew
8.6
Overall
8.0
Comfort
8.0
Reviews
1 / 20
10.0
ExcellentCourtney,Sep 2026
DEN - STL
Boarding
8.1
Entertainment
7.5
Food
7.0
Crew
8.6
Overall
8.0
Comfort
8.0
Reviews
1 / 20
10.0
ExcellentCourtney,Sep 2026
DEN - STL
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 locationsFairview Heights
O'Fallon
Fenton
Swansea
Eureka
Maryland Heights
Collinsville
Wentzville
Edwardsville
Glencoe
Chesterfield
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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 7,457,451 searches. Data last updated September 17, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$57 | Average$204 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$182 | Average$329 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$196 | Average$355 | FlexibilityNo cancel fee | On-time63% |