$40 Find Cheap Flights from St. Louis to Colorado

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from St. Louis to Colorado departing on 3/18. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Colorado

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from St. Louis to Colorado, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from St. Louis to Colorado, as well as popular online travel agencies
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Flight Deals

Cheap Flights from St. Louis to Colorado

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours
Denver
Denvernonstop$79
Aspen
Aspen1 stop$269
Grand Junction
Grand Junction1 stop$239
Durango
Durango1 stop$228
Montrose
Montrose1 stop$225
Hayden
Hayden1 stop$211
Gunnison
Gunnison1 stop$396
Cortez
Cortez1 stop$415
Vail
Vail1 stop$269
Denver
Denvernonstop$79
Aspen
Aspen1 stop$269
Grand Junction
Grand Junction1 stop$239
Durango
Durango1 stop$228
Montrose
Montrose1 stop$225
Hayden
Hayden1 stop$211
Gunnison
Gunnison1 stop$396
Cortez
Cortez1 stop$415
Vail
Vail1 stop$269

Book Cheap St. Louis to Colorado Plane Tickets

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from St. Louis to Colorado that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from St. Louis to Colorado

Mon, Mar 2 - Mon, Mar 9
Frontier Logo
1:54 pm - 3:30 pm
STL
-
DEN
2h 36mnonstop
Frontier Logo
6:35 am - 9:49 am
DEN
-
STL
2h 14mnonstop
$79Frontier
Mon, Mar 16 - Mon, Mar 23
Frontier Logo
8:12 pm - 9:49 pm
STL
-
DEN
2h 37mnonstop
Frontier Logo
6:35 am - 9:49 am
DEN
-
STL
2h 14mnonstop
$80Frontier
Sat, Feb 28 - Wed, Mar 4
United Airlines Logo
4:30 pm - 8:27 pm
STL
-
HDN
4h 57m
1 stop
United Airlines Logo
3:30 pm - 8:26 pm
HDN
-
STL
3h 56m
1 stop
$211United Airlines
Sat, Feb 28 - Wed, Mar 4
United Airlines Logo
4:30 pm - 8:27 pm
STL
-
HDN
4h 57m
1 stop
United Airlines Logo
1:36 pm - 10:14 pm
HDN
-
STL
7h 38m
2 stops
$216United Airlines
Mon, Feb 23 - Sat, Feb 28
American Airlines Logo
5:12 am - 11:34 am
STL
-
MTJ
7h 22m
1 stop
American Airlines Logo
10:35 am - 5:13 pm
MTJ
-
STL
5h 38m
1 stop
$225American Airlines
Tue, Feb 17 - Sat, Feb 21
American Airlines Logo
6:00 am - 12:40 pm
STL
-
EGE
7h 40m
1 stop
American Airlines Logo
4:17 pm - 11:59 pm
EGE
-
STL
6h 42m
1 stop
$269American Airlines
Wed, Mar 18 - Wed, Mar 25
Southwest Logo
2:15 pm - 8:40 pm
STL
-
COS
7h 25m
1 stop
Southwest Logo
10:20 am - 7:55 pm
COS
-
STL
8h 35m
2 stops
$298Southwest
Wed, Apr 29 - Mon, May 4
Southwest Logo
10:25 am - 6:05 pm
STL
-
COS
8h 40m
2 stops
Southwest Logo
4:05 pm - 12:15 am
COS
-
STL
7h 10m
1 stop
$313Southwest
Tue, Feb 10 - Sat, Feb 14
Delta Logo
7:10 am - 12:41 pm
STL
-
HDN
6h 31m
1 stop
Delta Logo
1:49 pm - 11:36 pm
HDN
-
STL
8h 47m
1 stop
$319Delta
Mon, Mar 2 - Mon, Mar 9
Delta Logo
6:00 am - 12:25 pm
STL
-
COS
7h 25m
1 stop
Delta Logo
1:28 pm - 9:06 pm
COS
-
STL
6h 38m
1 stop
$329Delta
Booking Insights

KAYAK's insights & trends for St. Louis to Colorado flights

Get data-powered insights and trends into flights from St. Louis to Colorado to help you find the cheapest flights, the best time to fly and much more.

What is the cheapest St. Louis to Colorado flight route?

Data is based on round-trip flight searches on KAYAK over the past month.

The cheapest ticket to Colorado from St. Louis found in the last 72 hours was to Denver, at $89 round-trip. The most popular route is from St. Louis (STL) to Denver (DEN), and the cheapest round-trip airline ticket found on this route in the last 72 hours was $89.

Can I save money by flying with a layover from St. Louis to Colorado?

The average round-trip price for all non-stop flights, flights with one layover, and flights with two layovers for the route found by users searching on KAYAK in the last 2 weeks.

No, with an average price for the route of $279, prices are generally cheapest when you fly direct.

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from St. Louis to Colorado, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from St. Louis to Colorado is October, when tickets cost $177 (return) on average. On the other hand, the most expensive months are March and July, when the average cost of round-trip tickets is $330 and $282 respectively.

What’s the cheapest day of the week to fly from St. Louis to Colorado?

The average price of all round-trip flights from St. Louis to Colorado clicked on KAYAK for each day over the last 12 months.

If your flying dates are flexible, you should consider flying to Colorado on a Wednesday, as we generally find the cheapest rates on that day for this route. On the other hand, Sunday is the most expensive day to fly from St. Louis to Colorado. For your return ticket, we recommend flying on a Friday and avoiding Sundays for the best deals.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from St. Louis to Colorado, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from St. Louis to Colorado, you should book around 2 weeks before departure, which saves you about 18% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 11 weeks before departure.

Good to know

Low seasonDecember
Cheapest flight$40
Best time to beat the crowds but there is an average 11% increase in price.
Most popular time to fly with an average 20% increase in price.
Flight from St. Louis to Denver

FAQs - booking Colorado flights

  • How does KAYAK find such low prices on flights from St. Louis to Colorado?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from St. Louis to Colorado.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from St. Louis to Colorado?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from St. Louis to Colorado is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from St. Louis to Colorado?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly from St. Louis to Colorado with an airline and back with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from St. Louis to Colorado?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying from St. Louis to Colorado up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

  • What is the cheapest time of day to fly to Colorado?

    The cheapest time of day to fly to Colorado is generally at night, when round-trip flights cost $184 on average. Morning departures are around 33% more expensive than evening flights, on average. The most expensive time of day to fly to Colorado is generally in the afternoon, which is peak travel time and where the average cost of a ticket is $478.

Top tips for finding cheap flights to Colorado

  • Looking for a cheap flight? 25% of our users found tickets from St. Louis to the following destinations at these prices or less: Denver $146 one-way - $240 round-trip

Reviews of the top 5 airlines serving from St. Louis to Colorado

 
See real verified KAYAK customer reviews for airlines flying from St. Louis to Colorado. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from St. Louis to Colorado? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
8.0
SouthwestOverall score based on 4272 reviews
8.1Boarding
8.6Crew
7.5Entertainment
8.0Comfort
7.0Food
Airline reviews

I appreciate the staff who allowed me to board though I arrived a little late! Regarding the assigned seating, I had booked my flight before this change and wasn't aware of the change at the time, and so I didn't select a seat at booking as I didn't realize it was relevant. Better communication about the change would have been helpful for preparing.

10.0 ExcellentMeghan, Feb 2026
MCO - DEN
Read more Southwest reviews

I appreciate the staff who allowed me to board though I arrived a little late! Regarding the assigned seating, I had booked my flight before this change and wasn't aware of the change at the time, and so I didn't select a seat at booking as I didn't realize it was relevant. Better communication about the change would have been helpful for preparing.

Pretty seamless, just a tad bit late in taking off and landing.

Everything a cheap airline should be at normal airline rates.

Sacrament staff are always polite and helpful. Airport is easy to maneuver and boarding is straightforward.

Delays delays delays. Late taking off, late landing, wait for a gate, etc.

Near 4 hour flight with only 1 service. Had to use call button to request water. Internet and power not working until into flight. Internet would stop working during flight.

The Southwest employees (all two of them) were very nice and cheerful despite the fact the line to self-check a bag (simply drop it off) was hundreds of people long. Thank God I arrived early to the airport because I stood in this line for at least an hour. Once on the flight that had been delayed by an hour, we had no Wi-Fi and thus no entertainment. Finally, I hope the investor strong arm tactics against Southwest pay off in a short-term windfall to your C-Suite because the rest of you are screwed. I have been a faithful Southwest customer for 15 years due to everything you just got rid of. I'm flying to Idaho and Washington in October, both places I used to simply book with Southwest without a second thought now with Frontier (Washington) and United (Idaho) because they offer everything the "new" Southwest does but cheaper and at better times, destinations, etc. This really makes me sad...

Flights delayed by 4-6 hours. Boarding was a mess and unclear. Bags were not at arrival airport and had never even been put on the plane. No idea when I’ll get them. Don’t fly into Denver!

Southwest is typically delayed, and it gets wearisome. It is no longer a discount airline and you get way less than you pay for when it comes to comfort and Ce.

We sat on the plane on the tarmac for 4 hours.

I didn't take this flight. I changed the flight. Why am I getting surveys and notifications on flights that I change. Seems like a defect with Kayak.

Delta One is extraordinary. I fly business when somebody hires me. I just wonder why there is such a chasm between business class and the insanely inhumane and nonsensical coach. The seats are not large enough to fit even my tiny wife. We fly 10% of what we did because we don’t want to pay 5-10 k but for $400 it’s unbearable. It seems like the accountants took over and made stupid decisions. Screw in 20 extra seats and make it so unbearable that people fly 90% less. Just put the damn price up and put some proper chairs in. But business, yay.

Timing, quality of service, promptness and courtesy of the staff

It was last minute due to weather - considering - it was amazing! Good smiles, friendly staff and they were making sure we knew what was going on when and where.

delta last minute gave me a boarding pass for a different flight with no confirmation that they were changing it

The service from the flight attendants were of supreme quality. They greeted and treated everyone with a wide smile. This is totally absent nowadays. Kudos to them!!!!

Excellent flight and got us around tough weather. Only issue was seat TV did not work and crew tried to reboot.

Very large passenger too space from my own seat. Arm board couldn’t be lowered because of his size. It wads very uncomfortable trip, as the flight was full couldn’t move anywhere having back pain because of the position in which I was the entire flight.

was sitting in the jet bridge for 10 minutes in -20 degree weather waiting for my bag

Outdated equipment in disrepair, wifi inoperable. Broken seats, taped air vents, generally poor condition, the 717 showed its age and lack of upkeep.

HORRIBLE, my initial flight was cancelled, they made me pay $200 extra dollars and that got cancelled as well! After 6 cancellations I decided to get a refund because I needed to get home to my babies. Out of $1000+ dollars they offered me only $40 in refund! Totally unacceptable! The flight that they cancelled I was able to fly it on another airline. I had to spend $400 on one way tickets just to get home! I’m still getting the runaround.

The flight was delayed by two de-icings. The seatbelt did not work correctly. It did not stay tight.

Hotter than Hades in August. Why, why do crews think that in the winter when we are already dressed for cold weather we need a cabin that is 82 degrees. Even the vents were blowing hot air.

Flight was delayed. De-icing took a while. When we landed had to wait for another plane to vacate our gate. Just an overall bad experience.

Not good - outbound flight was delayed and missed my connection even though I got to the gate after running through the airport - the agent would not let me on because the door was closed (flight had not left). There was no notification from United - overall experience was very disappointing. Additionally, I was downgraded from first class to coach on the alternative flight

United have really come back. Airport and boarding process is clear and good, app and information also very good

Flight was delayed only slightly before takeoff due to traffic control. However, the flight arrived early to ORD. Good flight. United has been very reliable for me.

The entertainment available didn’t work for anyone on the flight. Long 6 hr flight with no entertainment option and the staff didn’t know until an hour into the flight when we made sure they knew about it. They had no way to fix it.

Late FA meant slow boarding. WiFi did not work. I’m a medium plus sized passenger. The seatbelt was for the first time ever barely fitting. And we delayed on the tarmac 40 min

My husband and I had boarded the flight from Denver to Chicago, and one of the last passengers to get on the plane opened the overhead bin above my husband's seat and threw his bag out of the bin to make space for his own. He said, "Mine is bigger!" The flight attendant supported the new passenger. They didn't care that my husband has two artificial knees and must have the foot room in front of his seat to be able to fit his legs in -- and to be able to stand, much less walk, at the end of the flight. I have never seen this happen before, and it was a disaster.

The screens were inoperable for movies and such, but everything else was just fine

For a 5 1/2 hour flite i considered the "business class" to be subpar. The seats were just ok, no amenities, really nothing more than a long domestic flight. Frankly disappointed.

Delayed an hour due to operational issues. Minimal apologies or care for the significant inconvenience caused. Landed at nearly 1am and they still couldn’t find ground staff to get us off the plane promptly.

This was one of the most frustrating travel experiences I've had to date. I had changed my flight day of to this one as it was slated to depart on time. It ended up being so delayed that my original flight took off before this one did. The boarding process began but eventually stopped and everyone had to get off the plane as a problem was identified. The person at the front desk just tried to laugh it off as if this wasn't already a huge inconvenience. From there, we eventually got to board only to sit at the gate for an additional hour because of some additional issue. This was extremely frustrating and caused a lot of stress.

Update to handle the delay was very bad, crews no smiles or welcome or thanks. Don’t care attitude

It would be nice to have some low carb options in the snacks.

I was trying to take 2 one and a half hour one way trips and I experienced almost 20 delays over the course of those two trips. Only a few of them were due to weather the rest was disorganization

No gates avail at DFW so our incoming had to wait 30 mins for a plane to push back because they Had mechanical. We boarded 90 mins delayed and then we had a mechanical. Come on American…do better. Also at my seat the tray table had not been cleaned. Floor had not been cleaned. But captain and flight Att were very picture and apologetic.

Crew was helpful and cheerful especially when they had no refreshments to work with. The plane was never serviced and had nothing but limited water and coffee onboard. For the price point, a concern of services.

Flight was smooth, quick and felt safe. The 2 delays not happening would have been better but I guess that happens in the airline industry

It was costly and difficult to check in. $85 to take a small suitcase with me, carry on or checked and $75 on the return trip, Plus $25 if I didn't check my self in check in $25, because I couldn't do it on the kiosk. Small very uncomfortable seats, waited on the runway for near an hour each way. It was my worst flight to date.

Due to weather, my flight was delayed, further delayed, then canceled. I eventually got through to a support person who helped me find a different route out of MSP, but to get to DIA, they didn't want to, but eventually did help with the connection ticket purchase. But even this replacement flight was delayed time and time again, and I would have missed my connecting flights and I didn't want to get stuck in a layover city, so after 12 hours at the airport with two young boys who were very tired, we just cancelled our plans and spent the week at home, instead of Nana's.

I knew going into this that Frontier, being a low cost carrier, would be pretty bare bones and charge for most extras but this was made up for by the fact that the airplane was a reasonably new Airbus, every employee was great and best of all, Everett Washington is an amazing airport - thanks Frontier for flying there!!!

Seats were new and comfortable. Staff was fine. Missed my connection due to weather -which wasn’t their fault- but got no help at all. Gate staff sent me to customer service, which was and stayed unstaffed. Sign with QR code directed me to call or chat. Chat was useless. Call was returned after an hour. No itinerary offered by Frontier could get me home in less than 30 hours. Rebooked with another airline and got a partial refund that came to about 10 percent of what I paid to get home.

The experience was good. No frills but I got there safe and sound and on time.

As every law enforcement agency I could imagine surrounded the plane and we didn’t disembark for 2 hours and then had to stick around for another hour to go get our personal belongings after leaving them behind and being bused away from the plane, it was scary and inconvenient. We were given no information as to why this was happening. Lack of communication with passengers was disappointing.

Frontier Airlines was AWFUL. I was an hour early for my flight and the lady refused to check me in. I had to purchase a whole new ticket with a different airline.

Late, terrible communication, horrible planning of passenger seating until the literal last minute. One of the worst flying experiences of my life. Y'all suck

First of all, we never got on the connecting flight to Denver. They delayed our flight for two hours. If we would have gotten on that flight, we would have been stuck in Denver for 13 hours. So we re- routed our flight for a straight through flight to Oklahoma two days later. THEN, they delayed that flight for two hours. After that we were able to finally get on our flight and come home. Frontier Airlines - one of the worst airlines I have ever been on.

Terrible communication with weather delay, lost baggage, near impossible to reach customer service

Everything you need to know for your flight from St. Louis to Colorado

Information on your arrival and departure airports