Find cheap flights from St. Louis to Colorado

Find cheap flights from St. Louis to Colorado

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St. Louis (STL)
Colorado
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Good to know

Low season

April Best time to beat the crowds with an average 5% drop in price.

High season

December Most popular time to fly with an average 16% increase in price.

Average price round-trip

$377 (avg. price over the last 2 weeks)

Good deal round-trip

$97 or less

Good deal one-way

$63 or less

Top tips for finding cheap flights to Colorado

  • Looking for a cheap flight? 25% of our users found tickets from St. Louis to Colorado for the following prices or less: to Denver $63 one-way - $97 round-trip
  • Book at least 2 weeks before departure in order to get a below-average price.
  • High season is considered to be November and December. The cheapest month to fly to Colorado is August.
  • Morning departure is around 2% more expensive than an evening flight, on average*.
*Average of the lowest prices shown in KAYAK’s search results for departures within the next 30 days

FAQs - booking Colorado flights

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Top 4 airlines serving Lambert-St Louis to Colorado

Scores according to KAYAK customer reviews

7.9
Delta
Overall score based on 28,935 reviews
8.1
Boarding
7.8
Comfort
8.5
Crew
7.8
Entertainment
7.5
Food
Airline reviews

Pros: "Nothing, the flight was canceled without a refund. I highly recommend canceling all business with kiwi in the future."
Cons: "My flight could have occurred or I could have been refunded."

Pros: "Being on time with everything."
Cons: "Nothing"

Cons: "Really felt happy on time touch down nice journey with delta"

Cons: "No mechanical failures or delays would be nice"

Pros: "Friendly crew"

Pros: "pilot was great... made the landing at key west seem easy!"
Cons: "Flight attendants seemed to really like their jobs!"

Pros: "The crew was amazing! The seat was comfortable."
Cons: "Used the self check in kiosk to begin! That was awesome! But after that I still had to stand in line to check in my bags. That part of the process took a bit longer than expected."

Pros: "Nothing special"
Cons: "That was the most uncomfortable and cramped seat I had ever had on a plane flight. Even sitting on the pillow did not help."

Pros: "I like that I arrived at my destination safely."
Cons: "My allergies were bothering me due to the airlines allowing animals to travel as passengers, in this case a rabbit. I am very allergic to animals. My breathing was compromised."

Pros: "The flight attendant from IAD to MSP called Bernadette was wonderful!"

Pros: "This had one of the best attendants I have encountered. She was extra friendly and made us feel good."

Cons: "Everything was perfect!"

Pros: "Friendly staff. Entertainment selection is impressive (though I didn't use it). Drinks and snacks are provided."
Cons: "Boarding process was time consuming due to poor organization from Delta. Unloading process takes forever for the same reason. Despite booking at the same time my fiancee and I didn't get seated next to one another."

Cons: "The flight was 2 hours delayed.. this cause a lot of inconvienece.."

Pros: "Everything was on time and efficient. I also liked that the captain came on and updated us on arrival, turbulence, weather, etc."

Cons: "Flight was delayed out of St. Louis causing several of us to miss our connecting flight from Salt Lake City to Portland. Delta was of very little help in assisting us in making a connecting flight. They could have at least helped with travel arrangements and provided us with a little food, a pillow and a blanket as we waited in their terminal for the next flight on their airline which was a several hour wait. I understand these things happen but the passengers didn't cause the problem and Delta needs to take care of people better if they expect to earn repeat business."

Cons: "Crew was grumpy and Curt. Seats still smaller than a kindergarten class, and didn't even serve water."

Pros: "The flight was on time. Airport personnel were courteous & efficient. Airplane was clean. Pilot was friendly. A passenger had a peanut allergy so Delta distributed almonds, instead. Nice. Overall, I like Delta."
Cons: "Leg room was just barely adequate. It was a small plane-nothing could be done about that."

Cons: "Ac not working at last 30 minutes of flight."

Cons: "They changed my departure hours three times"

Pros: "Nothing"
Cons: "We lost our whole vacation and had to pay for the plans fare twice because My last name was spelled wrong on our tickets and we were unable to use them because my passport didn’t match the name on the ticket. We had to rebook everything pay almost twice as much for the plane fare, our Lodi g cost more and our trip was delayed for two weeks. Vyama is blaming us for spelling our name wrong and claimes that it’s our fault this happened because everything is automated. There saying they don’t touch anything that we enter into the booking but somehow everything they claim we entered is now in all capital letters and the space between our first name and middle name is now gone and all run together. The coustomer service number gets you to someone in India. I have tried to get this addressed four times now at first they tried to place the responsibility on the airlines now us and they have hung up on me twice. Kayak has been worthless, they also just pass the responsibility on to someone else. We will never use them again ant I intend to make sure that this mess is put out in social media to hopefully keep others from having their travel plans ruined by their flawed system."

Pros: "Friendly and attentive staff. Would definitely recommend . Flight departed and arrived on time."

Cons: "They changed my flight to a different one departing 2 hours earlier and did not notify me! The original flight was still available & they would not let me take it despite my reservation paper work. CRAZY! I have a two hour drive to the airport this gave me the option to leave home at 2:30am or go the night before and pay for a hotel. Flight was managed by DELTA who also did not care! All involved blamed each other. Beware"

Pros: "Great service and staff. On time both directions."

Cons: "Sandwich for dinner"

Cons: "3 hrs delay My first fly was cancell Atl- Mty So ,they booking me next fly atl-Qro I have to stay weathing 9 hrs and just water and cookies"

Pros: "In flight movies"
Cons: "The flight was 3 hours late taking off which made us miss our connection to chicago so we are stuck in Atlanta tonight with unplanned expenses we were not planning on!"

Pros: "Newer plane with entertainment"
Cons: "was a great flight"

Pros: "Very friendly crew"
Cons: "Seatbelts very short given ample seat size"

Pros: "Everything from the check-in to the landing was great. We were well informed about what was going on with out luggage (we were on a regional flight) and the assortment of free snacks were superb! I guess I'll be a returning customer"
Cons: "I was expecting some form of entertainment (radio, overhead monitor, etc) on the CRJ700. But it really don't take away from the experience since T-Mobile partnered with the Wi-Fi service and I received a free hour of Wi-Fi!"

Pros: "I liked that we finally arrived."
Cons: "I didn't like the lack of communication on Delta's behalf by their employees throughout our plane delay process. We were very delayed, and would be getting alerts on our phones before anyone told us what was going on. The forced us to change planes and didn't explain what the plan was or how we why we were transitioning. A lot of passengers had to ask each other what was going on, due to this lack of direction."

Pros: "Crew was excellent everything served was of great quality, all the amenities were solid and flight was comfortable and on time."
Cons: "The only complaint was the extreme use of air conditioning that made it a necessity to use many blankets to keep warm from freezing."

Pros: "Modern plane from ATL to BOS. On board games were a fun distraction."

Cons: "My flight got to New York so late!!!! I missed my international flight."

Cons: "Not great communication from gate or staff on board. Failed to provide adequate water. No ice on super warm flight. Just bad experience overall."

Pros: "It was wonderful to have a non-stop from Rome to Atlanta. The flight was comfortable and punctual. The in-flight entertainment was very good and helped pass the long flight."
Cons: "I liked the complimentary beverage service and many meal and snack interludes, although the food was sub par, especially the snack. I don't know how you can mess up crackers, but they were terrible, even slathered with the accompanying marinara. Also not sure that I ever met a shortbread cookie I didn't like until this trip; why lace it with artificial strawberry flavor?"

Pros: "All Good"
Cons: "Read above."

Pros: "Everything"
Cons: "Everything was perfect"

Pros: "Spacious, clean, great host and hostesses. The flight arrived at our destination 30 minutes early."
Cons: "Nothing."

Cons: "Cancelled my flight then re-booked me for the next day; was able to then find a flight same day but 7 hours later. That then was delayed another 4 hours and I had to buy a rental car to drive home instead. Thus far they have been unresponsive in getting me a refund for my travel. Don't fly Delta."

Pros: "Both flights landed early. Flight attendants were excellent and very helpful."
Cons: "Small plane to Minneapolis with one bathroom and the flight to sna didn't have my request for a gluten free meal."

Pros: "Newer plane! Comfortable"
Cons: "Nothing just great"

Cons: "Not enough water on the flight and we landed in a parking lot and shuttled back to the airport."

Cons: "turbulance"

Pros: "The flight attendants were excellent! Very attentive to passenger needs and wants"
Cons: "The seats are just economy seats with the middle seat left open"

Pros: "I was cleared for standby! Flight attendant at the stl gate is always friendly and willing to help! I love her!"
Cons: "I waited almost 6 hours on the phone the night before the flight to get on standby! Almost didn't get the flight! Was charged $50 only to not get on my next flight because it was over booked! Flight attendant was very rude!"

Pros: "I liked that I was able to get able to get an earlier flight!"
Cons: "I don't like that I had to pay $50 extra dollars for standby on both legs of my flight! I am a very loyal delta customer and these past times flying I feel like my favorite airline is turning into the bad airlines delay everytime, problems with the plane fare prices too high! I'm starting to think about taking my business elsewhere!"

Pros: "10 minutes early departure"
Cons: "There isn't enough seats in the gate area and sitting on the runway for 10 extra minutes we could have been early"

Pros: "Pleasant crew. Efficient loading and gate-check."
Cons: "No inflight entertainment. Very small overhead bins."

Pros: "Timelness"
Cons: "More leg room"

Pros: "Seat uncomfortable. I am an elite flier and was put in an n uncomfortable middle seat with no choice."
Cons: "Seat should with choice."

Cons: "When the delayed flight landed, the crew should help expedite those connecting to other flights. They should announce our connecting gates so that we don’t have to look it up."

Pros: "Nothing"
Cons: "Handicap issues. We were exiting on the tarmac in Charlotte- all crew left us on the plane waiting for assistance to get off. Finally when someone showed they would not come up the ramo to get my Mom. I backed her down myself while 5 bewildered airport workers looked confused."

Cons: "2 hour delays on both flights of a round trip"

Cons: "4 hour plane availability delay - of course planned on weather but not planning"

Cons: "Could be more caring staff"

Pros: "Flight left St. Louis on time,"
Cons: "My connecting flight was cancelled while I was in the air. Customer service was SWAMPED with cancellations with only a handful of staff to help. My plane was a mechanical cancellation so I received a food and hotel voucher. Trying to get another flight from LaGuardia to YYZ was horrible."

Pros: "One flight attendant was very nice and petsonable."
Cons: "Already checked in and then flight canceled 10 hours before departure. Paid for preferred seating but rebooked on smaller aircraft full and had to sit in last row. Not happy and arrived 2 hours latet than original flight. Tried to explain this at gate to American employee but she told me to sit down until name was called. Probably could have had better seats earlier if she could have listened to my issue but she wouldn't listen to me. Didn't even have the chance to tell her what had happened."

Pros: "A cheap option to upgrade to 1st was offered that ended up being a net 0 cost upgrade for me so I took it. Comfortable on an old (but oh so nice) aircraft."
Cons: "Arrived 30 minutes early to the airport but then had to sit at a remote pad so that we ended up being 5 minutes late to the gate. A short transfer was made even more difficult, and a massive waste if time and fuel sitting and waiting. Figure out your gates early and better, and move around if needed. At the very least, bring up some stairs and buses to get passengers to the terminal and then tow the aircraft in when you have a gate available."

Pros: "Great seats in first class"
Cons: "N/a"

Pros: "Room between rows Entertainment from St Louis to Phoenix"

Cons: "Flight was cancelled with no compensation"

Pros: "We got to our destination safely, and American provided us with extra legroom seats."
Cons: "Service was curt and there was only phone-based entertainment."

Pros: "Fast"

Pros: "The pilot was great. Avoided turbulence and arrived about 20min early. Easy to find seat and stow bag. Smooth takeoff and landing."
Cons: "Alaska airlines was who I thought I was riding with but the itinerary changed past min. Gate change and the airline itself was changed. Really confusing since I printed my boarding pass the night before."

Pros: "Smooth boarding. On time flight"
Cons: "No gluten free snacks:("

Pros: "Everything went smoothly."

Cons: "Me 6’ 200 lb sitting in middle seat next to somebody that needed 2 seats for self (pls understand I’m not unsensetive nor prejudice just stating a fact). I requested to sit in last row (of both sides of plane that were empty but attendant said sears reserved for attendants - 2)."

Pros: "Quick boarding, on time departure and early arrival. No waiting for a gate at LGA upon arrival - excellent."

Cons: "Flight connections time was not enough for mam with infant.we missed the flight should better set up that kind of big airport"

Pros: "I was so happy I could check in online and boarding was a breeze. I actually got to sit by the window when my original seat was in the middle. So nice of the ladies to suggest it to me."
Cons: "No complaints"

Cons: "The video monitor for my seat was broken. So, low entertainment score."

Pros: "everything was on tyime"

Pros: "On time take off"

Pros: "A nonstop flight, with a friendly efficient crew, met my expectations. A crew member went above and beyond when I asked for a coffee stirrer with my coke and ice."
Cons: "I've been spoiled by another airline's access to screens on the back of the headrest. I have my own hand held devices to entertain myself instead."

Cons: "Flight was late, got a message from Kayak that it was delayed 3 hours...thank goodness I happened to check again, because then it was only delayed for 41 mins, then it gave me an update that it was only 21 mins delayed, then went back to 41! Pretty inconvenient, and it would have been nice to get a text, not just some silent pop up"

Pros: "Got to La Guardia almost 26 minutes early but then waited FORTY minutes for the gate!"
Cons: "AA needs better coordination with the horrible La Guardia airport"

Cons: "Delayed a total of four hous!"

Cons: "good"

Pros: "Flight was on time, staff was friendly and boarding was organized."
Cons: "I'm a small person (5'-2", 105lbs) and I didn't have room to breathe in that tiny little seat."

Pros: "Smooth - trouble free - calm process"

Pros: "Arrived to the airport well ahead of time and encountered lines so long that we were not able to make our flight. Only 2 attendants working and so many people had to be rebooked we didn't get another flight for 3 days. Did I mention I was traveling with a baby?"

Pros: "On time arrival"
Cons: "Everything else"

Pros: "Nothing"
Cons: "The storage are very small, by the time i boarded everything was full. I had to hand carry bags and i had to put it in front of me which is a very small space already, on top of that i had the window sit so i had no space to move. it was very uncomfortable, and flight was delayed. We sat there for an hour before taking off but i understand its due to the weather but it was my worst plane ride not worth 300dollars. I will not ride american airline again."

Pros: "JAL is customer oriented and it's always a pleasant experience. Unfortunately, though the return trip is also JAL, the cabin crew isn't."

Cons: "Everything was great."

Pros: "The flight attendants were great and very friendly!"
Cons: "The wifi wasn't very good so I couldn't access the in flight entertainment I also had my own snacks so I didn't buy any food"

Cons: "No usb or wall chargers. No inseat entertainment and glitchy wifi entertainment"

Pros: "Boarding was good, Good flight , good service , plane was small for the distance with limited space for movement ,"

Pros: "On time. Good leg room."
Cons: "Valet flight, i.e. even normal sized carry-on cannot be stowed above the seat We arrived at the gate 20 min before departure, due to TSA delays. But they closed the door and no one was around to even talk to. At least they put us in the next flight.... Still, as we're not checking in any bags, they could have let us in."

Cons: "Got to charlotte with 80 minutes to connect. Sat on the tarmac for 60 waiting for a gate. Missed connection by <5 minutes. Thanks, AA!"

Pros: "Non stop"
Cons: "Airline"

Cons: "Boarding took forever, the flight was over 2 hours late which caused me to miss my connecting flight and my military orders were not honored - I still had to pay extra to take all my gear back to my duty station. Never had that issue with any other American airline."

Pros: "Crew was fine even when we had to sit on the ground for 1 1/2 hours for a repair."
Cons: "American Airlines didn't honor my choice of seats."

Pros: "I don't know how airlines get away with all the stipulations and regualations they have in the buying process there is. Otho g I like about the scam artist they are"
Cons: "The fact they they can just make it a policy and then because the employees have to have a job and enforce it blows my mind. 200 dollar transfer fee plus the difference in the ticket when it's over two weeks in advance. You people are scam artist"

Cons: "Would be nice to know ahead of time if flight is equipped with an in seat television so as to be prepared to bring headphones."

Pros: "We arrived safe."
Cons: "Departure 1.5 hours late. Missed connection. Travel took 16 hours instead of 6 hours."

Pros: "Everything was timely."
Cons: "No complaints"

Pros: "I was very pleased that the attendant gave me a free drink since I had a military ID. It was very kind of her."
Cons: "The flight was delayed multiple times. We were never informed as to why this was. It was very frustrating since I had a connecting flight into Tucson from Dallas. I got off the plane with twenty minutes to get to my next flight which was not in the same terminal. The plane was also incredibly hot while we waited to take off, I was beginning to become uneasy and nauseous."

Pros: "He was the epitome of the Friendly Skies. Chatted with whom wished to chat was quite near those that wanted to snooze on this early morning flight."

Pros: "Smooth and positive communication."

Pros: "Seats tip back pretty far, without cramping up leg room for the person behind you too much."
Cons: "The passenger behind me was playing games on the screen on the back of my seat. So, my seat was constantly being tapped and it was more difficult to sleep."

Pros: "Nothing"
Cons: "Nothing"

Pros: "a little bit more foot-room than my previous flight on a different airline."

Pros: "Everything was smooth"

Pros: "I managed not to use toilet."
Cons: "An epic storm (April 27-May 4) caused my bicycle tour across MO to flood out during our trip. Rescheduling my flight back to CA cost &230..same price as RT. Gouging people leaving a massive flood! The governor of MO declared a State of Emergency yet my trip cancellation insurance didn't cover what was clearly beyond my control. I'm left with some hard feelings."

Pros: "Security was quick and efficient. Boarding was extremely organized. The airline attendants were attentive. The pilot on United informed us when the possibility of hitting turbulence occurred so we could adjust accordingly. Overall, great travel experience."

Pros: "Boarding and landing ahead of schedule"

Pros: "Generally it was ok. Travelling is so horrible these days that "ok" seems pretty great."
Cons: "My bag was lost but my husband's, checked at the same time, made it."

Pros: "Nothing"
Cons: "Refused to delay connecting flight in Denver even though severL of where already on ground in delayed flight coming into Denver. Albuquerque flght was still at gate when I got there, having run through airport along with several others. We were refused admission to plane despite delay being United's fault. Unacceptable! I will avoid flying United in the future whenever possible"

Pros: "I didn't fly.I bought the ticket for my son. He had no complaints. You should ask in your questionnaire if the booked flight was for self or someone else."

Pros: "Got there on time."
Cons: "Private screening does not work well. Very little kneeroom. No room in seat back pockets to put anything."

Cons: "Flight was delayed so long I missed my connecting flight and spent 18 hours traveling rather than 8."

Pros: "On-time departure from Cancun but early arrival in Denver (relatively mild jet stream?). Otherwise, fairly typical United cattle carrier."

Cons: "Delayed and got downgraded without refund of difference"

Cons: "My friends dad passed away and was unable to get money back to go to his funeral. Plane was a small express plane which was never mentioned. Had to check bag because overhead bins were too small. No wifi. Dad and Kid took my assigned seat."

Pros: "Sucks"

Pros: "Friendly few, clean plane, and on time"
Cons: "It was way too hot on the plane. I understand it's hard to find a happy medium with people on temperature but this flight was too warm, especially with people traveling with winter wear on."

Pros: "Good crew"
Cons: "The usual. - crowded, smelly"

Pros: "The seats had plenty of leg room and I enjoyed the movie selection"
Cons: "The food left much to be desired"

Pros: "Crew was great"
Cons: "Great aircraft!"

Pros: "Flight was on time; both ground and flight crews were pleasant and efficient."
Cons: "They were out of ginger ale, my beverage of choice :-)"

Pros: "Good communication and helpful."
Cons: "Delays"

Cons: "Terrible experience ever!!!!! Didn't get economy plus that I paid for, seats didn't recline and luggage got damaged and was not replaces or compensated for."

Pros: "Nothing because they didn't allow us to board the flight because there was 20mins left til the plane departed. Also the tickets were bought with 24hrs and they didn't refund or give us a flight credit."
Cons: "They didn't allow us tothe tickets were bought with 24hrs and they didn't refund or give us a flight credit."

Pros: "Flying in America gave me no problems. Things only got terrible after we left Denver."

Pros: "The service was food"
Cons: "Lack of leg room!!! After my bicycle box was inspected they failed to secure my bike the way I had it in the box. Bike was flipping around in box. Bent rear brake calipers. Bent brake hoods. Rear skewers were uncoupled. No way to treat a $10,000 bike! Very upset!"

Pros: "Had a stroller, two bags, and a car seat and the check in staff helped us tag everything and loaded it for us. It was nice to see the Billings staff go above and beyond in my families time of need."

Pros: "They sent me a text message telling me it was canceled"
Cons: "Unfortunately, despite the text message saying the flight was canceled, the ANA ground staff in Taipei that we talked to assured us it was not canceled. But it was. And so ensued 24 uncomfortable hours of pain. Thanks, United."

Cons: "A la ahora de irnos hubo muchos contratiempo por el tiempo pero por el vuelo después que nos fuimos fue excelente"

Cons: "Bad snacks. Need biscotti"

Cons: "Little more time between flights would be nice"

Pros: "It was a quiet and smooth ride."

Cons: "Unreliable wifi."

Pros: "The flight was snooze and the flight staff were friendly!"
Cons: "N/A"

Pros: "Crew was nice and friendly."

Cons: "Luggage compartment too small even for a rolling laptop bag"

Pros: "The crew. Short and sweet flight."
Cons: "Small seats. Bad coffee."

Pros: "The flight attendant finally took care of it after I complained a couple of times."
Cons: "That you changed our seats, and, that there was no room in any of the overhead bins. So, the flight attendant told me that I needed to fight my way through the people coming toward me back up the aisle and check every overhead bin all the way back up to see if there was room for my one suitcase. Others had brought more than one bag up there. Finally they checked my one carry on bag. The ride was also really bumpy, worst that we've ever experienced. But that was due to weather conditions."

Pros: "Good service"
Cons: "Delay in air"

Pros: "I like the seats and the leg space .they were very comfortable ."
Cons: "No comment"

Pros: "Getting off the plane"
Cons: "Bathrooms weren't working, huge lines in aisle, lackluster service. Overhead bins were full by Group 3. late takeoff."

Pros: "Wifi on flight"

Cons: "One strange thing happened on my United airlines flight. The crew announced before we boarded that there wasn't enough overhead space for rolling bags and encouraged us to check them in. Upon boarding they announced that all overhead space in the back was full. I sat in the back and noticed that the crew closed the overhead compartments even though they were mostly empty. Another passenger opened an empty one and the crew came over and closed it right away, though many people were still boarding. What's going on?"

Pros: "United seems to be recycling which is a good thing."
Cons: "The obnoxious child sitting behind me. He kicked the seat and pulled on the tray."

Pros: "New (to me) lime sparkling soda And a cookie too! Seemed to be a little more seat and leg room."
Cons: "I only wish your branded credit card did not cost$95.00 after first year."

Pros: "San Antonio flight to Denver delayed too long where could not make connection in Denver to Toronto. Had to make other flight arrangements."

Pros: "Under booked flight was a plus!"

Pros: "Rain delayed our take off but most of the time was made up. No complaints!"
Cons: "Forced to check our carry on suitcase even though there was plenty of room above the seats."

Pros: "This added almost $100 to the face. I'll try to avoid Frontier in the future. Gotcha capitalism!"
Cons: "Cheap fare until it changed with the bag fee"

Pros: "Started with the nickel and diming during check in. The app wouldn't take my card so I had get on the website. Apparently buying the ticket doesn't give you a seat, you have to pay extra for that. Taking more than a laptop bag or purse, that's extra. Right there, your low fare is shot to h#ll. Definitely check the hidden costs before booking. Then came a 5 hour delay of the flight, apparently the plane had mechanical issues at it's previous stop. Frontier provided $10 meal vouchers, which doesn't go far in an airport. Seats don't recline at all and you feel like you're in a cattle car. The seat back tray is about 6" and doesn't hold much. The combination of turbulence and a pilot yanking the plane around during landing brought out the air sick bags by several passengers around me. Then on the ground, he was racing around and taking turns like an Indy500 race car. I seriously thought he was going to do a handbrake turn into the parking spot. Frontier provided vouchers worth $100 per ticket for the flight, but only good for another Frontier flight. I don't think so..."
Cons: "Several hidden costs. Uncomfortable seats Rough landing"

Pros: "Overall good flight."
Cons: "I’m tall so comfort is not an option unless I want to pay for it. No food unless I want to pay for it. No entertainment unless I want to bring it."

Pros: "The staff was wonderful. Great people with great personality."
Cons: "Everything from getting on the plane was not only difficult, but uncomfortable, and with a lack of detail towards the customer. From the small tables at knee level, to the chair angle, this entire experience was either wrought with an inability to sit easily and definitely was painful every time I needed to move."

Pros: "The prices"
Cons: "Paying for a carry on Seats do not recline No complimentary beverages Flight was delayed and we rarely received updates I understand that you charge for everything in order to offer better prices, but by the time the customer pays to bring on luggage, we are paying the same price as an airline that allows baggage for free with inclusive drinks, snacks and seats that recline."

Cons: "Weather delays happen. But Frontier left me stranded in a Denver and offered me no options other than a refund? No rebooking no hotel nothing."

Cons: "Frontier's new seats and fees."

Pros: "The attendants were very helpful and friendly. The plane was incredibly clean and comfortable. I would fly frontier again!"
Cons: "The frontier website. Not easy to use and disk not allow me to add tsa precheck or buy my bags online."

Pros: "My only good then was that I had wonderful passengers around me that were conversationalists who were entertaining and helpful!!"
Cons: "Can't you learn how to communicate faca to face with people? Let us know personally why we keep getting held up for take off, why we are being left in the dark, andehy you can't schedule more accurately! It doesn't help to fly somewhere if you miss the event you went to attend! Try compensating for our inconveniences for a change!!!!"

Pros: "new jet. enough leg room (i'm male, 5-10). Overhead bins are normal size (can hold typical carry on), not the microscopic ones. Everything was on time."
Cons: "STL ticket counter was only staffed 2 hours before the flight -- which makes sense if they didn't have more flights, but the signs weren't big and complete enough for passengers to realize what was going on and how we would check our luggage. So we were standing around a bit confused. Once Frontier people showed up, it was fine. Also, coming back to STL, I had a 2 hr shuttle bus ride that was leaving 30 minutes after arrival, and although the plane arrived on time, the luggage didn't reach me until 37 minutes after, so I had to get a hotel room for the night. I don't know how luggage handling works, so maybe not Frontier's fault at all. 30 minutes isn't much time, but it was a direct flight, so I thought it would work."

Pros: "not much"
Cons: "I have been more comfortable on church basement folding chairs that the seats on Frontier. I did pay to move to seat 1A, and it still felt like a torture device."

Cons: "My baggage took FOREVER to come back"

Cons: "Very bumpy flight and it takes forever to get your luggage"

Pros: "Landing and getting off the plane."
Cons: "Frontier is definitely cheap for a reason."

Cons: "Airplane not clean. No entertainment at all."

Cons: "The flight was delayed several times, never even offered a free drink for the trouble"

Pros: "I don t like"
Cons: "They charge Cary on"

Cons: "Flight delayed an hour"

Pros: "The plane left on time and we arrived in Denver ahead of schedule."
Cons: "We arrived in Denver ahead of schedule and then sat on the tarmac for 50 minutes before de-boarding. There was a $30 charge for a checked bag. You had to pay for any snacks. There was no entertainment."

Pros: "The folks at security check were attempting to add humor while keeping the lines moving."
Cons: "The guy who took our checked bag had no personality. He never even looked at us."

Cons: "Fronteir created new seats that do not recline, are quite thin and small tray tables that don't lock. The consequence is that the man next to me couldn't lean back enough, so slumped onto me most of the flight. A one year old behind me constantly pulled up and down the unmatchable tray table and kicked my thin chair -- so I felt every little tiny foot. The stewardess refused to give us water when our row asked and they forgot to call boarding zone 2 when boarding so it was a mess. I would say Frontier was a terrible airline. Their discounted prices are a farce as they charge for a seat and carry-on luggage, so I may as well have paid for a regular fare from a more comfortable airline."

Pros: "On time!!"
Cons: "Everything was good!!"

Pros: "I like and it went good with no problems."
Cons: "The baggage Claim which I didn't know each baggage claim have each groups of what the name that you flying out which no one told me about that so its new to me ."

Pros: "Nothing will not recommend them"
Cons: "The price quoted did not include their fees for a carry on - $30 both ways! Feels unethical."

Pros: "The price."
Cons: "Multiple delays, uncomfortable seats."

Pros: "I liked the seats. They didn't seem worn out."
Cons: "The price of drinks and food. They should be comparable to a grocery store if you're going to charge for every little convenience."

Pros: "Nothing"
Cons: "Everything, such a rip off"

Pros: "Frontier staff tried their best to keep people in good spirits..."
Cons: "2 hour delay, I was freezing cold on the plane and the attendant said that they didn't have blankets. They pushed the alcohol sales and we were not even offered a bag of peanuts."

Pros: "the crew made the best of a miserable corporate policy; the baggage arrived - 45 minutes after landing."
Cons: "2.0 hours late boarding; boarded 2x; lousy information; surly condescending station manager; insane baggage counter hours; no connection information in flight despite airline full responsibility for everyone on the plane being behind schedule.; connecting flight still at gate when 10 people tried to board and were not given access until a near riot occurred; no one seemed care at all. A woman with 5 week old child, a senior citizen with a cane, a woman recovering form surgery all RAN from gate to the other (about 1/2 miles) only to be told they were too late, the terminal door was closed. Only after pounding on the door, cajoling the customer service people 10 feet away and telling 50 others waiting in the service area did the door open!"

Cons: "online check in and seat assignments is so concentrating on upselling that it is difficult to use. I also don't appreciate the bait and switch pricing. The flight costs $x, but then if you want a seat not located in the unheated cargo hold, that is extra."

Pros: "Plane was clean. Seats were very comfortable l, but not much leg room"
Cons: "They charge for for everything on this flight. Checking in - it cost $35 to check your bag in - $40 of you want to board with it! I do all the work and I have to pay more? Then to pick a seat - any seat - it is another $5 - $25. I understand that for premium seating (ext, etc) but any seat? Finally - drinks and snacks - that costs money too. While the fare looks cheap - beware of all the add ons. At a minimum, you have an additional $70 to $100 to the price of the ticket This does not turn out to be a cheaper price....beware."

Pros: "Free baggage for military"
Cons: "Loud announcing and not classy attempts to upsell us during the flight"

Cons: "My flight was supposed to leave at 8:p.m. We left at 12:30 am. Hot in at. 2:00 am. Had to be at work at 7:00 am. Got home at 3:00 am instead of 10:00. How do you think people were. They were very disappointed Terrible airline"

Pros: "Worse than Southwest Airlines. Uncomfortable."
Cons: "Uncomfortable seats and crew didn't smile much."

Cons: "The worst thing was having to sit on the tarmac for over an hour. This was after a very bumpy landing and having to pay for carry tons is ridiculous"

Pros: "The rates were less expensive so I guess you get what you pay for, but at the gate bag check was 40 per bag, I was expecting more in the realm of 25. (Yes I know I should have checked online) then we get to the gate and the fight was over booked and delayed. When we tried to communicate with the staff about questions pertaining to connecting flights they seemed unable/ unwilling to help. Overall not worth the discounted rate."
Cons: "I really think the baggage fee is way over the top. And perhaps a little customer service training for your people"

Cons: "My flight got delayed 6hours and it was to leave at 2:37 in the morning and instead I wanted to just get the flight the next day but they still charged me $100, nor did they offer to put me in a hotel I paid for that too."

Pros: "The flight was fairly smooth with only a few turbulents"
Cons: "I would have liked free packet of peanuts or pretzel and either club soda or water"

Pros: "I got where I was going to."
Cons: "One zone isn't even through the door and the next zone is called and all we do is stand in the very hot jetway for nearly 15 minutes. Being charged to pick our seat and for our luggage is ridiculous. It should be included in the price, if you have to raise the price then at least people would know better the true cost of their travel. Being charged for a drink! Having $1.99 put on a credit card! Wrong."

Pros: "The Staff was friendly"
Cons: "the flight was only cheaper until you had to either check a bag or pay to carry on! Pay to drink a soda or anything! The seats are the most stripped down uncomfortable airline seats I have ever experienced. After all the add on costs, there is no value in the cramped, crowded, uncomfortable flight. Also, on every flight at least half of the passengers were not aware of the baggage policy until it was too late to check it for less money and had to pay extra to carry on. To top it off, we had to change gates at the last minute, resulting in having to go out of the Domestic terminal and sent us all back through the check in!!! We should have at least been able to fly through the pre check if not rerouted us through another way that did not require the total shoes off, open bags, metal detection all over again!!!"

Cons: "My luggage was misplaced on the plane and I waited for an hour for it and it went to the wrong section. I paid two dollars for a soda. St. Louis frontier desk is not open from 930-3pm which is crazy ridiculous. Also your plans are extremely uncomfortable and have become just like military planes. $30 for a carry on is excessive and $25 for a checked back? Absolutely not. I will not fly frontier again."

Cons: "The flight was delayed and the airline charges for everything. They tried to charge me for my CARRYON bag which is hilarious, and I proceeded to say I would not pay that charge. The attendant let me board the plane anyway and I put my carryon in the overhead without an issue, which deeply concerns me. It seems as if Frontier arbitrarily tacks on that charge, tricking their customers like con artists who will fall for this absurdity. The air conditioning did not work well and they almost forgot to give us water. Maybe they even charged for the water. The attendants were rude. Dont fly Frontier unless you really really really need to save a dime or two."

Pros: "I got on quickly and off quickly. Or flight was slightly faster than predicted due to weather."

Cons: "Charged for carry on and food/drink"

Pros: "Left on early and arrived early."
Cons: "Not very comfortable seats. Should be able to get water at least."

Pros: "Nothing"
Cons: "Flight was delayed. Frontier could have cared less"

Pros: "I felt safe throughout the whole trip; the landing was on if the smoothest landings I've felt ever. Frontier is the only airline I have taken."
Cons: "n/a"

Cons: "Ended up paying more than I would have for the flight if I just went with the quality carriers. Through kayak you don't get any bags. Would have been the same price through the fro tier site and included a bag."

Pros: "The captain and stewardess were very nice and accommodating."
Cons: "The plane was very very dirty. It hadn't been cleaned in quite a while."

Pros: "The new seats are very comfortable."

Read more about Delta
COVID-19 information

Safety measures for airlines flying from St. Louis to Colorado

Airlines flying from St. Louis to Colorado have enacted additional safety measures and adjusted policies to better accommodate travelers. Policies vary by airline.

Heightened sanitation

Daily cleaning, installation of cabin HEPA filters on flights from St. Louis to Colorado

Mandatory masks

Masks required on board, masks provided on flights from St. Louis to Colorado

Social distancing seating

Middle seats unavailable to book on flights from St. Louis to Colorado

Pre-flight testing

Testing for antibodies, testing for symptoms for flights from St. Louis to Colorado

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