$42+ 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 5/4. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — STL
Apr 9 — Apr 161
Round-trip
1 adult, Economy
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Cheapest flights from Colorado to St. LouisExplore 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 March 10, 2026.
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 March 10, 2026.
This Cheapflightsfares deal was found by Cheapflights users on 3/6. 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 3/166:35 am
DEN
- STL
Nonstop2h 14m
Frontier
Wed 3/258:12 pm
STL
- DEN
Nonstop2h 37m
Frontier
Deal found 3/6![Frontier logo]()
$87
This Cheapflightsfares deal was found by Cheapflights users on 3/7. 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 5/14:09 pm
DEN
- STL
Nonstop2h 12m
Frontier
Fri 5/88:12 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/7![Frontier logo]()
$88
This Super.com deal was found by Cheapflights users on 3/7. 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 4/46:40 am
DEN
- STL
Nonstop2h 08m
Frontier
Sat 4/118:16 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/7![Frontier logo]()
$91
This Frontier deal was found by Cheapflights users on 3/8. 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 3/306:35 am
DEN
- STL
Nonstop2h 14m
Frontier
Mon 3/308:12 pm
STL
- DEN
Nonstop2h 37m
Frontier
Deal found 3/8![Frontier logo]()
$92
This Frontier deal was found by Cheapflights users on 3/7. 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.
Sat 3/286:35 am
DEN
- STL
Nonstop2h 14m
Frontier
Mon 3/308:12 pm
STL
- DEN
Nonstop2h 37m
Frontier
Deal found 3/7![Frontier logo]()
$96
This Kiwi.com deal was found by Cheapflights users on 3/6. 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 3/286:35 am
DEN
- STL
Nonstop2h 14m
Frontier
Sat 3/288:12 pm
STL
- DEN
Nonstop2h 37m
Frontier
Deal found 3/6![Frontier logo]()
$99
This Cheapflightsfares deal was found by Cheapflights users on 3/9. 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
Sat 4/118:16 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/9![Frontier logo]()
$100
This Kiwi.com deal was found by Cheapflights users on 3/9. 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 3/276:35 am
DEN
- STL
Nonstop2h 14m
Frontier
Mon 3/308:12 pm
STL
- DEN
Nonstop2h 37m
Frontier
Deal found 3/9![Frontier logo]()
$103
This Frontier deal was found by Cheapflights users on 3/6. 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 3/166:35 am
DEN
- STL
Nonstop2h 14m
Frontier
Sat 3/288:12 pm
STL
- DEN
Nonstop2h 37m
Frontier
Deal found 3/6![Frontier logo]()
$104
This Cheapflightsfares deal was found by Cheapflights users on 3/8. 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 5/24:20 pm
DEN
- STL
Nonstop2h 12m
Frontier
Sun 5/38:06 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/8![Frontier logo]()
$106
This Cheapflightsfares deal was found by Cheapflights users on 3/6. 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 4/135:53 pm
DEN
- STL
1 stop28h 26m
Frontier
Sat 4/188:17 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/6![Frontier logo]()
$107
This Frontier deal was found by Cheapflights users on 3/6. 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 3/166:35 am
DEN
- STL
Nonstop2h 14m
Frontier
Mon 3/238:12 pm
STL
- DEN
Nonstop2h 37m
Frontier
Deal found 3/6![Frontier logo]()
$108
Best flights from Colorado to St. LouisDiscover carefully curated flight deals from Colorado to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated March 10, 2026.
Discover carefully curated flight deals from Colorado to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated March 10, 2026.
This CheapOair deal was found by Cheapflights users on 3/5. 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.
Tue 5/53:41 pm
DEN
- STL
1 stop30h 38m
Frontier
Fri 5/88:12 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/5![Frontier logo]()
$145
This United Airlines deal was found by Cheapflights users on 3/7. 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 4/151:48 pm
DEN
- STL
Nonstop2h 08m
United Airlines
Sat 4/188:54 am
STL
- DEN
Nonstop2h 33m
United Airlines
Deal found 3/7![United Airlines logo]()
$189
This Delta deal was found by Cheapflights users on 3/8. 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 5/71:55 pm
COS
- STL
1 stop6h 34m
Delta
Sat 5/96:00 am
STL
- COS
1 stop7h 48m
Delta
Deal found 3/8![Delta logo]()
$221
This Southwest deal was found by Cheapflights users on 3/6. 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 4/255:40 am
STL
- DEN
2 stops7h 10m
Southwest
Deal found 3/6![Southwest logo]()
$227
This American Airlines deal was found by Cheapflights users on 3/7. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/1711:41 am
DRO
- STL
2 stops11h 05m
American Airlines
Mon 4/2012:27 pm
STL
- DRO
2 stops10h 16m
American Airlines
Deal found 3/7![American Airlines logo]()
$390
This United Airlines deal was found by Cheapflights users on 3/6. 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 4/115:45 pm
DEN
- STL
Nonstop2h 09m
United Airlines
Tue 4/148:54 am
STL
- DEN
Nonstop2h 33m
United Airlines
Deal found 3/6![United Airlines logo]()
$201
This Southwest deal was found by Cheapflights users on 3/6. 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 4/204:05 pm
COS
- STL
2 stops6h 50m
Southwest
Sat 4/256:10 am
STL
- COS
2 stops8h 30m
Southwest
Deal found 3/6![Southwest logo]()
$231
This United Airlines deal was found by Cheapflights users on 3/8. 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 3/273:22 pm
GJT
- STL
1 stop4h 19m
United Airlines
Sun 4/56:05 pm
STL
- GJT
1 stop5h 12m
United Airlines
Deal found 3/8![United Airlines logo]()
$259
This Delta deal was found by Cheapflights users on 3/5. 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 3/255:15 pm
GJT
- STL
1 stop6h 06m
Delta
Sun 3/296:00 am
STL
- GJT
2 stops11h 35m
Delta
Deal found 3/5![Delta logo]()
$294
This Southwest deal was found by Cheapflights users on 3/8. 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.
Sun 5/318:35 pm
COS
- STL
2 stops15h 20m
Southwest
Thu 6/45:35 am
STL
- COS
1 stop4h 20m
Southwest
Deal found 3/8![Southwest logo]()
$278
This Southwest deal was found by Cheapflights users on 3/5. 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 4/235:20 pm
COS
- STL
1 stop5h 30m
Southwest
Mon 4/276:00 pm
STL
- COS
1 stop7h 05m
Southwest
Deal found 3/5![Southwest logo]()
$287
This United Airlines deal was found by Cheapflights users on 3/7. 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.
Tue 3/311:24 pm
EGE
- STL
1 stop8h 04m
United Airlines
Sat 4/182:40 pm
STL
- EGE
1 stop6h 42m
United Airlines
Deal found 3/7![United Airlines logo]()
$289
This Southwest deal was found by Cheapflights users on 3/6. 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 4/12:35 pm
DEN
- STL
2 stops5h 50m
Southwest
Sat 4/47:15 am
STL
- DEN
2 stops7h 25m
Southwest
Deal found 3/6![Southwest logo]()
$292
This United Airlines deal was found by Cheapflights users on 3/9. 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 5/710:40 am
COS
- STL
1 stop5h 17m
United Airlines
Sat 5/99:00 am
STL
- COS
2 stops9h 26m
United Airlines
Deal found 3/9![United Airlines logo]()
$296
This United Airlines deal was found by Cheapflights users on 3/5. 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 4/13:25 pm
GUC
- STL
1 stop4h 29m
United Airlines
Sun 4/58:54 am
STL
- GUC
1 stop4h 45m
United Airlines
Deal found 3/5![United Airlines logo]()
$301
This American Airlines deal was found by Cheapflights users on 3/5. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/254:46 pm
GJT
- STL
1 stop5h 12m
American Airlines
Sun 3/295:12 am
STL
- GJT
1 stop5h 53m
American Airlines
Deal found 3/5![American Airlines logo]()
$443
This Southwest deal was found by Cheapflights users on 3/6. 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 4/37:15 pm
DEN
- STL
Nonstop2h 00m
Southwest
Sun 4/56:20 am
STL
- DEN
Nonstop2h 25m
Southwest
Deal found 3/6![Southwest logo]()
$312
This United Airlines deal was found by Cheapflights users on 3/6. 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 4/95:45 pm
DEN
- STL
Nonstop2h 09m
United Airlines
Sat 4/118:54 am
STL
- DEN
Nonstop2h 33m
United Airlines
Deal found 3/6![United Airlines logo]()
$304
This American Airlines deal was found by Cheapflights users on 3/8. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/234:58 pm
GJT
- STL
1 stop5h 01m
American Airlines
Thu 4/305:20 am
STL
- GJT
1 stop7h 52m
American Airlines
Deal found 3/8![American Airlines logo]()
$454
This Southwest deal was found by Cheapflights users on 3/9. 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 5/85:20 pm
COS
- STL
1 stop3h 45m
Southwest
Sun 5/105:35 am
STL
- COS
1 stop6h 05m
Southwest
Deal found 3/9![Southwest logo]()
$313
This United Airlines deal was found by Cheapflights users on 3/6. 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.
Mon 3/305:45 pm
DEN
- STL
Nonstop2h 09m
United Airlines
Thu 4/26:05 pm
STL
- DEN
Nonstop2h 34m
United Airlines
Deal found 3/6![United Airlines logo]()
$304
This Southwest deal was found by Cheapflights users on 3/6. 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 4/134:05 pm
COS
- STL
1 stop5h 35m
Southwest
Mon 4/206:00 pm
STL
- COS
1 stop7h 05m
Southwest
Deal found 3/6![Southwest logo]()
$313
This United Airlines deal was found by Cheapflights users on 3/5. 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 3/278:20 pm
DEN
- STL
Nonstop2h 14m
United Airlines
Sun 3/295:15 am
STL
- DEN
Nonstop2h 41m
United Airlines
Deal found 3/5![United Airlines logo]()
$322
This United Airlines deal was found by Cheapflights users on 3/8. 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 7/235:34 pm
DEN
- STL
Nonstop2h 09m
United Airlines
Sun 7/265:10 am
STL
- DEN
Nonstop2h 22m
United Airlines
Deal found 3/8![United Airlines logo]()
$327
This United Airlines deal was found by Cheapflights users on 3/6. 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 5/228:45 pm
DEN
- STL
Nonstop2h 12m
United Airlines
Sun 5/249:06 am
STL
- DEN
Nonstop2h 24m
United Airlines
Deal found 3/6![United Airlines logo]()
$327
This Southwest deal was found by Cheapflights users on 3/6. 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.
Sun 3/225:05 pm
HDN
- STL
1 stop5h 30m
Southwest
Thu 3/265:45 am
STL
- HDN
1 stop8h 05m
Southwest
Deal found 3/6![Southwest logo]()
$418
This United Airlines deal was found by Cheapflights users on 3/7. 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 8/129:24 am
GJT
- STL
1 stop6h 07m
United Airlines
Sat 8/154:40 pm
STL
- GJT
1 stop6h 26m
United Airlines
Deal found 3/7![United Airlines logo]()
$329
This Southwest deal was found by Cheapflights users on 3/8. 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 3/2312:10 pm
MTJ
- STL
2 stops5h 45m
Southwest
Fri 3/275:45 am
STL
- MTJ
1 stop8h 05m
Southwest
Deal found 3/8![Southwest logo]()
$419
This United Airlines deal was found by Cheapflights users on 3/6. 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.
Tue 3/2412:01 pm
HDN
- STL
1 stop4h 59m
United Airlines
Wed 3/259:00 am
STL
- HDN
1 stop4h 36m
United Airlines
Deal found 3/6![United Airlines logo]()
$329
This United Airlines deal was found by Cheapflights users on 3/7. 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.
Tue 3/243:39 pm
MTJ
- STL
1 stop6h 55m
United Airlines
Wed 3/259:00 am
STL
- MTJ
1 stop6h 37m
United Airlines
Deal found 3/7![United Airlines logo]()
$329
Last-minute flights from Colorado to St. LouisDiscover last-minute flight deals from Colorado to St. Louis. Data last updated March 10, 2026 and is based on user searches.
Discover last-minute flight deals from Colorado to St. Louis. Data last updated March 10, 2026 and is based on user searches.
This Cheapflightsfares deal was found by Cheapflights users on 3/6. 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 3/166:35 am
DEN
- STL
Nonstop2h 14m
Frontier
Wed 3/258:12 pm
STL
- DEN
Nonstop2h 37m
Frontier
Deal found 3/6![Frontier logo]()
$87
This Frontier deal was found by Cheapflights users on 3/6. 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 3/166:35 am
DEN
- STL
Nonstop2h 14m
Frontier
Sat 3/288:12 pm
STL
- DEN
Nonstop2h 37m
Frontier
Deal found 3/6![Frontier logo]()
$104
This Frontier deal was found by Cheapflights users on 3/6. 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 3/166:35 am
DEN
- STL
Nonstop2h 14m
Frontier
Mon 3/238:12 pm
STL
- DEN
Nonstop2h 37m
Frontier
Deal found 3/6![Frontier logo]()
$108
This Kiwi.com deal was found by Cheapflights users on 3/9. 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 3/276:35 am
DEN
- STL
Nonstop2h 14m
Frontier
Mon 3/308:12 pm
STL
- DEN
Nonstop2h 37m
Frontier
Deal found 3/9![Frontier logo]()
$103
This Frontier deal was found by Cheapflights users on 3/7. 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.
Sat 3/286:35 am
DEN
- STL
Nonstop2h 14m
Frontier
Mon 3/308:12 pm
STL
- DEN
Nonstop2h 37m
Frontier
Deal found 3/7![Frontier logo]()
$96
This Kiwi.com deal was found by Cheapflights users on 3/6. 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 3/286:35 am
DEN
- STL
Nonstop2h 14m
Frontier
Sat 3/288:12 pm
STL
- DEN
Nonstop2h 37m
Frontier
Deal found 3/6![Frontier logo]()
$99
This Frontier deal was found by Cheapflights users on 3/8. 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 3/306:35 am
DEN
- STL
Nonstop2h 14m
Frontier
Mon 3/308:12 pm
STL
- DEN
Nonstop2h 37m
Frontier
Deal found 3/8![Frontier logo]()
$92
This Super.com deal was found by Cheapflights users on 3/7. 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 4/46:40 am
DEN
- STL
Nonstop2h 08m
Frontier
Sat 4/118:16 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/7![Frontier logo]()
$91
This Delta deal was found by Cheapflights users on 3/6. 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 4/88:15 am
COS
- STL
1 stop7h 52m
Delta
Wed 4/156:00 am
STL
- COS
1 stop7h 17m
Delta
Deal found 3/6![Delta logo]()
$221
This Cheapflightsfares deal was found by Cheapflights users on 3/9. 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
Sat 4/118:16 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/9![Frontier logo]()
$100
This Cheapflightsfares deal was found by Cheapflights users on 3/6. 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 4/135:53 pm
DEN
- STL
1 stop28h 26m
Frontier
Sat 4/188:17 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/6![Frontier logo]()
$107
This Kiwi.com deal was found by Cheapflights users on 3/6. 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 4/136:40 am
DEN
- STL
Nonstop2h 08m
Frontier
Mon 4/208:17 pm
STL
- DEN
Nonstop2h 33m
Frontier
Deal found 3/6![Frontier logo]()
$111
One-way flights from Colorado to St. LouisSearch for one-way flight options from Colorado to St. Louis. Find affordable one-way fares based on user searches. Data last updated March 10, 2026.
Search for one-way flight options from Colorado to St. Louis. Find affordable one-way fares based on user searches. Data last updated March 10, 2026.
This Kiwi.com deal was found by Cheapflights users on 3/6. 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 5/44:20 pm
DEN
- STL
Nonstop2h 12m
Frontier
Deal found 3/6![Frontier logo]()
$42
This Expedia deal was found by Cheapflights users on 3/9. 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.
Fri 4/36:40 am
DEN
- STL
Nonstop2h 08m
Frontier
Deal found 3/9![Frontier logo]()
$44
This Expedia deal was found by Cheapflights users on 3/9. 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.
Sat 4/116:40 am
DEN
- STL
Nonstop2h 08m
Frontier
Deal found 3/9![Frontier logo]()
$46
This Kiwi.com deal was found by Cheapflights users on 3/6. 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.
Sun 5/104:00 pm
DEN
- STL
Nonstop2h 12m
Frontier
Deal found 3/6![Frontier logo]()
$53
This Frontier deal was found by Cheapflights users on 3/6. 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 3/166:35 am
DEN
- STL
Nonstop2h 14m
Frontier
Deal found 3/6![Frontier logo]()
$54
This Kiwi.com deal was found by Cheapflights users on 3/10. 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 5/84:00 pm
DEN
- STL
Nonstop2h 12m
Frontier
Deal found 3/10![Frontier logo]()
$62
This Kiwi.com deal was found by Cheapflights users on 3/8. 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 3/276:35 am
DEN
- STL
Nonstop2h 14m
Frontier
Deal found 3/8![Frontier logo]()
$68
This Kiwi.com deal was found by Cheapflights users on 3/6. 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 4/281:09 pm
DEN
- STL
1 stop16h 41m
Frontier
Deal found 3/6![Frontier logo]()
$71
This Southwest deal was found by Cheapflights users on 3/7. 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 4/89:00 am
HDN
- STL
2 stops8h 00m
Southwest
Deal found 3/7![Southwest logo]()
$121
This United Airlines deal was found by Cheapflights users on 3/8. 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 3/261:32 pm
HDN
- STL
1 stop6h 09m
United Airlines
Deal found 3/8![United Airlines logo]()
$130
This Delta deal was found by Cheapflights users on 3/8. 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 3/184:10 pm
HDN
- STL
1 stop6h 15m
Delta
Deal found 3/8![Delta logo]()
$170
This American Airlines deal was found by Cheapflights users on 3/9. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/213:45 pm
COS
- STL
1 stop7h 14m
American Airlines
Deal found 3/9![American Airlines logo]()
$177
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 March 10, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $88 (Cheapflightsfares) |
One-way from | $42 (Kiwi.com) |
Popular in | June |
Cheapest in | January |
Average price | $299 |
Good round-trip deal | $227 or less |
Good one-way deal | $158 or less |
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 March 10, 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
Cheapest round-trip
DenverSt. Louis
DEN - STL
DENSTL
Denver Intl
Tue 5/5
3:41 pm-11:19 pm
1 stop30h 38m
Lambert-St Louis
Fri 5/8
8:12 pm-9:45 pm
Nonstop2h 33m
$145
DenverSt. Louis
DEN - STL
DENSTL
Denver Intl
Wed 4/15
1:48 pm-4:56 pm
Nonstop2h 08m
Lambert-St Louis
Sat 4/18
8:54 am-10:27 am
Nonstop2h 33m
$189
DenverSt. Louis
DEN - STL
DENSTL
Denver Intl
Sat 4/11
5:45 pm-8:54 pm
Nonstop2h 09m
Lambert-St Louis
Tue 4/14
8:54 am-10:27 am
Nonstop2h 33m
$201
Colorado SpringsSt. Louis
COS - STL
COSSTL
Colorado Springs
Thu 5/7
1:55 pm-9:29 pm
1 stop6h 34m
Lambert-St Louis
Sat 5/9
6:00 am-12:48 pm
1 stop7h 48m
$221
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
5:40 am-11:50 am
2 stops7h 10m
$227
Colorado SpringsSt. Louis
COS - STL
COSSTL
Colorado Springs
Mon 4/20
4:05 pm-11:55 pm
2 stops6h 50m
Lambert-St Louis
Sat 4/25
6:10 am-1:40 pm
2 stops8h 30m
$231
Grand JunctionSt. Louis
GJT - STL
GJTSTL
Grand Junction Regnl
Fri 3/27
3:22 pm-8:41 pm
1 stop4h 19m
Lambert-St Louis
Sun 4/5
6:05 pm-10:17 pm
1 stop5h 12m
$259
Colorado SpringsSt. Louis
COS - STL
COSSTL
Colorado Springs
Sun 5/31
8:35 pm-12:55 pm
2 stops15h 20m
Lambert-St Louis
Thu 6/4
5:35 am-8:55 am
1 stop4h 20m
$278
Colorado SpringsSt. Louis
COS - STL
COSSTL
Colorado Springs
Thu 4/23
5:20 pm-11:50 pm
1 stop5h 30m
Lambert-St Louis
Mon 4/27
6:00 pm-12:05 am
1 stop7h 05m
$287
VailSt. Louis
EGE - STL
EGESTL
Vail Eagle County
Tue 3/31
1:24 pm-10:28 pm
1 stop8h 04m
Lambert-St Louis
Sat 4/18
2:40 pm-8:22 pm
1 stop6h 42m
$289
Showing 1-10 of 60 resultsSorted by cheapest first
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.
DEN-STL
COS-STL
HDN-STL
GUC-STL
GJT-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 Colorado to St. Louis
USCO-STL
DEN-STL
COS-STL
HDN-STL
GUC-STL
What is the cheapest month to book a flight from Colorado to St. Louis?
Currently, February is the cheapest month in which you can book a flight from Colorado to St. Louis (average of $55). Flying from Colorado to St. Louis in June is currently the most expensive (average of $134). 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 March 10, 2026.
It’s optimal to fly from Colorado to St. Louis in the morning. By choosing this option you can save up to 13% on the cost of your flight, compared to a flight at noon.
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 February 21, 2026.
Travelers seeking maximum savings on their Colorado 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.
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 March 10, 2026.
The most flights from USCO to STL are scheduled on a Monday (17 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (4 on average).
How much does it cost to fly round-trip from Colorado to St. Louis?
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.
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
Browse thousands of different options on Cheapflights for your next trip
Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.
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Alternative routes for Colorado to St. Louis
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Complete your trip
Complete your trip to St. Louis by adding a car rental and/or hotel reservation to your travel itinerary.
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Find flights from Colorado to St. Louis, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Colorado and St. Louis flights
Browse other Colorado and St. Louis flight options. Last updated on March 10, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Other flights to St. Louis
Explore flights to St. Louis departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on March 10, 2026.
Colorado to St. Louis flights
Consider these flights traveling from Colorado to St. Louis.
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 March 10, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$58 | Average$167 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$166 | Average$391 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$177 | Average$353 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$248 | Average$427 | FlexibilityNo cancel fee | On-time71% |