STL - DEN

$30 Find Cheap Flights from St. Louis to Denver

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 Denver departing on 11/5. 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

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

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from St. Louis to Denver, 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 Denver, as well as popular online travel agencies
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Cheap Flights from St. Louis to Denver (STL-DEN)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from St. Louis to Denver 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 Denver

Sat, Oct 25 - Tue, Oct 28
Frontier Logo
7:52 pm - 9:20 pmSTL-DEN
2h 28mnonstop
Frontier Logo
6:00 am - 9:07 amDEN-STL
2h 07mnonstop
$69Frontier
Find Deal
Fri, Sep 19 - Sat, Sep 27
Frontier Logo
7:55 pm - 9:20 pmSTL-DEN
2h 25mnonstop
Frontier Logo
6:00 am - 9:06 amDEN-STL
2h 06mnonstop
$78Frontier
Find Deal
Fri, Oct 3 - Sun, Oct 5
Frontier Logo
7:55 pm - 9:20 pmSTL-DEN
2h 25mnonstop
Frontier Logo
6:00 am - 9:06 amDEN-STL
2h 06mnonstop
$82Frontier
Find Deal
Wed, Oct 8 - Mon, Oct 13
Frontier Logo
7:52 pm - 9:20 pmSTL-DEN
2h 28mnonstop
Frontier Logo
6:00 am - 9:07 amDEN-STL
2h 07mnonstop
$86Frontier
Find Deal
Tue, Sep 9 - Sat, Sep 13
Frontier Logo
7:55 pm - 9:20 pmSTL-DEN
2h 25mnonstop
Frontier Logo
6:00 am - 9:06 amDEN-STL
2h 06mnonstop
$87Frontier
Find Deal
Wed, Sep 10 - Wed, Sep 17
Frontier Logo
7:55 pm - 9:20 pmSTL-DEN
2h 25mnonstop
Frontier Logo
6:00 am - 9:06 amDEN-STL
2h 06mnonstop
$89Frontier
Find Deal
Tue, Aug 26 - Wed, Sep 3
Frontier Logo
7:54 pm - 9:23 pmSTL-DEN
2h 29mnonstop
Frontier Logo
6:00 am - 9:11 amDEN-STL
2h 11mnonstop
$96Frontier
Find Deal
Fri, Sep 5 - Tue, Sep 9
Frontier Logo
7:55 pm - 9:20 pmSTL-DEN
2h 25mnonstop
Frontier Logo
6:00 am - 9:06 amDEN-STL
2h 06mnonstop
$98Frontier
Find Deal
Sat, Aug 23 - Sat, Aug 30
Frontier Logo
7:54 pm - 9:23 pmSTL-DEN
2h 29mnonstop
Frontier Logo
6:00 am - 9:11 amDEN-STL
2h 11mnonstop
$99Frontier
Find Deal
Wed, Oct 8 - Wed, Oct 8
Southwest Logo
5:55 am - 7:15 amSTL-DEN
2h 20mnonstop
Southwest Logo
5:15 pm - 8:15 pmDEN-STL
2h 00mnonstop
$157Southwest
Find Deal
Expert advice

Expert advice for your flight from St. Louis to Denver

 
Snippets provided in this section are AI-generated based on a summarization of KAYAK-commissioned articles. The articles are presented as-is, for general informational purposes only, and may not be up-to-date. The opinions contained in the articles are original to the author and reflect their authentic experience, which may vary significantly from the experience of others.
KAYAK teamed up with top travel experts to share the best tips for your journey.
Airlines
Frontier

Opt for the Premium Bundle for priority boarding and extra legroom seats.


Check bags online for cheaper rates than at the airport.

Read more about Frontierby Stefanie Waldek
United Airlines

Consider Economy Plus for extra legroom, offering up to six inches more than standard economy.


Purchase Priority Boarding to ensure overhead bin space, automatically placing you in Zone 2.

Southwest

Set an alarm to check in exactly 24 hours beforehand for a better boarding position.


Enjoy two free checked bags, each up to 50 pounds, saving on baggage fees.

Read more about Southwestby Blane Bachelor
Airports
STL

Avoid peak hours at STL to minimize wait times. Early mornings and afternoons are busiest, especially in Terminal 2 with Southwest flights.

Read more about STLby Yulia Denisyuk
DEN

Take the RTD A line train from DEN to downtown Denver for a cost-effective 40-minute journey, connecting you to Union Station and city attractions.

Read more about DENby Harriet Baskas
Our travel experts
Stefanie Waldek

Stefanie Waldek

Expert on Frontier and United Airlines

Stefanie Waldek

Stefanie Waldek

Stefanie Waldek is a freelance space, travel, and design writer based in Saratoga Springs, NY. Her words have appeared in Space.com, Travel + Leisure, Condé Nast Traveler, Architectural Digest, and House Beautiful, among other publications. An expert in aviation and expedition cruising, Stefanie is frequently up in the air or on the sea, likely en route to Antarctica or the Arctic.

Read more
Blane Bachelor

Blane Bachelor

Expert on Southwest

Blane Bachelor

Blane Bachelor

Blane Bachelor is a journalist and editor specializing in travel and aviation who writes regularly for top global outlets. Born and raised in Florida, Blane has worked and lived in four countries, including the Netherlands, where she’s currently based with her family. Her favorite way to get to know a new destination is by running or riding a bike around town – or hearing a spooky ghost story about local history. She will always choose the window seat.

Read more
Yulia Denisyuk

Yulia Denisyuk

Expert on STL

Yulia Denisyuk

Yulia Denisyuk

Yulia is a freelance journalist who’s dispatched from 90+ countries. Her work focuses on cultures, adventure trips and air travel, appearing in NatGeo, NYT, CNTraveler, and more. For past assignments, she’s stayed with nomads in Mongolia and learned the art of Imigongo in Rwanda. She’s based in Chicago; in winter she often questions that decision.

Read more
Harriet Baskas

Harriet Baskas

Expert on DEN

Harriet Baskas

Harriet Baskas

Harriet is an award-winning journalist who is happiest in an airport or an unusual museum. Her stories about airports, air travel, and the business of travel have appeared on NBC News, CNBC, USA TODAY, The Points Guy and other outlets. She is the creator of the StuckatTheAirport.com blog and the author of nine books. When not out on the road or exploring the latest airport amenities, she’s home in Seattle getting ready for the next adventure.

Read more
Booking Insights

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

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

Find cheap flights to Denver
Find cheap flights to Denver

Planning a trip from St. Louis to Denver? KAYAK’s data-powered insights will help you find cheap flights. Learn the best time to fly, how early to book your ticket, and other tips to secure great prices.

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

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

For St. Louis to Denver, Wednesday is the cheapest day to fly on average and Sunday is the most expensive. Flying from Denver back to St. Louis, the best deals are generally found on Wednesday, with Sunday being the most expensive.

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from St. Louis to Denver, 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 Denver is September, where tickets cost $157 (return) on average. On the other hand, the most expensive months are March and June, where the average cost of round-trip tickets is $336 and $267 respectively.

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

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 $637, prices are generally cheapest when you fly direct.

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

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 Denver, 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 Denver, you should book around 2 weeks before departure, which saves you about 36% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 4 weeks before departure.

Good to know

Low seasonApril
Cheapest flight$30
Best time to beat the crowds with an average 4% drop in price.
Most popular time to fly and prices are also 26% lower on average.
Flight from St. Louis to Denver

When to book flights from St. Louis to Denver

Are your dates flexible? Find out the best times to travel from St. Louis to Denver based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from St. Louis to Denver

  • How can I fly from STL to DEN?

    Frontier and United operate several nonstop flights from STL to DEN that depart throughout the day. American and United operate several flights per day that have one stop. The layover for these flights is often in cities such as Chicago (ORD), Charlotte (CLT), and Dallas (DFW).

  • Does STL have a USO lounge?

    STL provides a USO lounge for active military service members and their families. The James S. McDonnell USO, located in Terminal 1 on the lower level opposite M6 baggage claim, is open 24h a day, 7 days a week, 365 days a year. All services and amenities at the USO are without charge. Some of these offerings include beverages, snacks, Wi-Fi, a DSN phone, laptops, and computers. You can also relax by watching cable TV, watching a DVD or a Blu-ray disc, or playing Xbox 360. The USO also has a seating area, a quiet area where you can sleep, a nursery, and toiletries.

  • Does STL have designated lactation areas for nursing mothers who might prefer some privacy?

    STL provides dedicated private spaces to mothers who want to nurse or breast pump in clean privacy. These lactation suites are located past security at Gates A10, C9, and E33. Each calm, clean room has power outlets for a breast pump, a sink, and a full back comfortable chair with a movable arm table. There is also an Ottoman and a bench so that additional people, such as baby’s siblings, can join mama in the space, with enough room for luggage.

  • How do I get into downtown Denver from the DEN airport?

    You can take the A Line of the RTD bus that runs to the center of Denver. Also, you can take a train that departs from DEN 4 to 6 times an hour. Public transportation from DEN is very convenient to get you into downtown Denver.

  • What is the cheapest flight from St. Louis to Denver?

    In the last 3 days, the lowest price for a flight from St. Louis to Denver was $30 for a one-way ticket and $69 for a round-trip.

  • Do I need a passport to fly between St. Louis and Denver?

    A passport is not required to fly from St. Louis to Denver.

  • Which airlines offer Wi-Fi service onboard planes from St. Louis to Denver?

    American Airlines, Delta, and Alaska Airlines offer inflight Wi-Fi service on the St. Louis to Denver flight route.

  • Which aircraft models fly most regularly from St. Louis to Denver?

    The Boeing 737-800 Passenger/BBJ2 (winglets) is the aircraft model that flies most regularly on the St. Louis to Denver flight route.

  • Which airline alliances offer flights from St. Louis to Denver?

    Star Alliance is the only airline alliance operating flights between St. Louis and Denver.

  • On which days can I fly direct from St. Louis to Denver?

    There are nonstop flights from St. Louis to Denver on a daily basis.

  • Which is the best airline for flights from St. Louis to Denver, Southwest or Delta?

    The two airlines most popular with KAYAK users for flights from St. Louis to Denver are Southwest and Delta. With an average price for the route of $295 and an overall rating of 8.0, Southwest is the most popular choice. Delta is also a great choice for the route, with an average price of $246 and an overall rating of 8.0.

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

    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 Denver.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Denver from St. Louis 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 Denver?

    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 to Denver with an airline and back to St. Louis with another airline. Booking your flights between St. Louis and DEN can sometimes prove cheaper using this method.

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

    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 to Denver from St. Louis up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

KAYAK’s top tips for finding a cheap flight from St. Louis to Denver

  • Looking for a cheap flight? 25% of our users found flights on this route for $121 or less one-way and $187 or less round-trip.
  • When you arrive at the Denver International Airport (DEN), you can ease the stiffness out of your muscles by getting a massage at the spa, The Massage, at the B concourse on the mezzanine level. Or you could try the Colorado Oasis or Xpres spas at DEN.
  • If when you arrive at DEN you need to pick up some necessities you couldn’t pack due to airline restrictions, stop at the Peak News and Gifts to get the toiletries and essentials you need before heading into Denver.
  • As part of the Lambert Art and Culture Program at the Lambert St. Louis International Airport (STL), the airport has installed a piano permanently in Terminal 1, so travelers are treated to live music as they make their way to their plane.
  • DEN is happy to provide service animals and pets with relief areas in all three terminals, in the middle of all the gates. For A, B, and C terminals, the pet relief areas are near the US mail drop areas. If you are in Jeppesen terminal, the pet relief area is on the northwest side of the second level.
  • If you want to park your car at STL before you head off to Denver, long-term parking lots are available in lots B and D for an affordable price, and payment is usually due at the time you exit the lot. Free shuttles that run every 10min can take you to your terminal.

Prefer to fly direct from St. Louis to Denver?

 
Direct data is based off flight results for the next 60 days. Find direct flights from all airlines flying direct from Lambert-St Louis to Denver Intl.
Find which airlines fly direct from Lambert-St Louis Airport to Denver Intl Airport, which days they fly and book direct flights.

Direct departures

Lambert-St Louis to Denver Intl

Monday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

Tuesday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

Wednesday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

Thursday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

Friday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

Saturday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

Sunday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

See more direct flights

Direct returns

Denver Intl to Lambert-St Louis

Monday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

Tuesday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

Wednesday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

Thursday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

Friday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

Saturday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

Sunday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

See more direct flights

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

 
See real verified KAYAK customer reviews for airlines flying from St. Louis to Denver. 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 Denver? 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 4241 reviews
8.1Boarding
8.6Crew
8.0Comfort
7.0Food
7.5Entertainment
Airline reviews

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...

4.0 OkayGreg, Jul 2025PDX - DEN
Read more Southwest reviews

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.

After a 3 hour layover in Denver my flight was delayed over 5 hours! No explanation; no assistance; no offer to provide compensation; no one at Southwest was willing to offer any assistance. 8 hours in the Denver airport - ridiculous!

Very good. Sad to learn Southwest is going start to charge for bags

WiFi on the flight was not working. Thus, entertainment options were limited.

I really like open seating. I hate that I've heard this is going away. This is one of the unique things that makes Southwest my goto choice.

Multiple delays and gate changes. Arrived at final destination 6 hours late. All rental cars had been taken.

For the first time in a long time we had a flawless experience with Southwest. Both flights were early and no mechanical errors at all. We were shocked and pleasantly surprised 😮.

Delayed and took off even later than the scheduled delay time

For a 69 year old with health problems I had the worse experience, no wheelchair when I entered a lady told me to sit and wait while a gentleman told me I had to walk to the Delta station, which I did. I had a carry on and a bag, and I was traveling with my service dog, which was on his carrier and the lady charged me for my carry on luggage, beside all the waiting cause of the delay, I had to walk to get my luggage cause no wheelchair showed up, I am so disappointed. I will get in touch with the company. I got home at 3:00 am, not good for my health situation.

Great experience on Delta. Staff from baggage check to flight attendants were very courteous and professional. My only issue was a personal preference for pretzels instead of the chips and cookies that were offered.

There was no problems, just a little uncomfortable with seats that do not lay back a little

Always good but we must do something about people in rows ahead of you that don't put their seats back up when they are suppose to. And It's rough to not be able to even lean over to get something out of my purse.

Flight was delayed, 30+ bags had to be gate checked. Crew were very friendly!

Everything was good until we were boarding our connection flight in Atlanta, we were told to gate check our carry-on, but when we got inside the plane, there was plenty of room in the overhead.

Did not know my son and I had different seating arrangements. He was fine, but it was disappointing.

Flight was canceled, and no effort was made to help with rebooking, no hotel vouchers, no car transportation and minimal food voucher and most places for food were closed by the time the voucher was given. Waited for 3 hours for bags. Simply the worst travel experience I have ever had

Food was surprisingly good but the WiFi was not great

Our flight was understandably diverted to a small regional airport in Laramie, Wyoming due to weather conditions, which I fully recognize and appreciate. However, the low rating stems from the experience that followed: passengers remained on board for over an hour without the option to deplane and stretch, despite the aircraft being stationary. Although the pilot opened the cabin door, only he was permitted to exit. Meanwhile, passengers grew increasingly uncomfortable as warm summer air entered the cabin through the open door, and being in the second row meant we were impacted immediately. While the flight attendants made efforts to keep everyone at ease, I believe allowing passengers to deplane briefly, given the extended delay, would have significantly improved the overall experience.

I never flew. Flight was canceled. DIA worst airport in the country. Avoid at all costs.

Very rough getting into denver. my kid threw up it was so rough.

Why wasn't this flight departure scheduled eith another crew so that it could leave on time? When we arrived in Denver we had so little time between flights we had run to the connecting flight. We should received some credit for the inconvenience.

I was supposed to be on business class at first class from Denver back to Miami due to weather changes. I missed my connection and it’s put on a flight to Fort Lauderdale. Instead of honoring my business class/1st class ticket, they put me in coach, but there were two first class seats open. I think it’s absolutely disgusting that I paid for first class $1300 ticket and they put me in economy and they had to open seats available and I have still not been refunded the difference. I ended up having to eat a snack box instead of the meal I was supposed to get and did not get home till 2 AM so I think that’s a little pathetic that I had to live off crackers for dinner And my poor dog ate some cheese and salami. Oh yes, apparently when they switched me to the new flight they forgot to mention I had a service dog

Excellent service despite turbulence during the flight. Flight attendants were remarkable!

Flight attendant moved my bag without notifying me and was rude to me when I asked him about it. There was no reason to move it.

Food choices were very limited. Taste of the dishes was average.

I liked all the informational texts. I always knew where to go and when .

Received an email the night before showing that there would be seatback entertainment on our flight. We get on and there was no seatback entertainment. And then it was a scramble to try to set up the iPads for the kids before takeoff so they could watch something for the four hour flight.

Very poor delay in dfw was really bad n long

Our flight was 1.5 hours delayed. There was no weather for the inbound flight, so I don't understand why. This meant a VERY late arrival and only a quick nap before my morning flight.

Because of rescheduling, they had to put me on a flight that didn't go through Dallas

It was very difficult to stretch my knee out and I am very short. I also had a torn tendon in my knee which made it extra uncomfortable anyways. My husband is 6'2" and I can't imagine him flying in that plane.

3 hour weather delay followed by 1 hour (and counting) maintenance delay. UGH!

Couldn’t get the door on the plane to close leading to a nearly 2 hour delay. But, hey at least they didn’t cancel the flight.

Flight was cancelled 3 hrs AFTER etd. Thetefore Missed connection from JFK to New Zealand . No accommodation provided… This cost ne aporox 1000 USD in extra expenses and turned whst should have been a 24 hr trip ftom Boston - New Zealand into a VERY expensive , late 70+ hr nightmare … Complete nonsense!!!

After we'd boarded , they canceled the flight. The crew didn't even know , we just all received text messages. Then after they deplaned us , AA was just like "too bad, go F your self, we sure ain't gonna help you"

The flight got delayed 2.5 hrs due to a maintenance issue that cause a domino effect. American should have spare planes for when something like this happens.

Delayed flight, so I switched fights to SFO to Phoenix , Phoenix to DSM. Excellent service through American Airlines

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

My tickets got canceled on me by your site and I didn't have a flight. Then you kept sending me emails on the status of q flight I didn't have tickets for.

Flight was late. Missed connecting in Denver. My new flight is more than 24 hours later and I have no room, vouchers, or compensation, and might also be bumped from the one tomorrow.

This was one of the first frontier airline flights this spring that wasn't delayed. It actually left on time. Some of the flight crew did not look happy, they didn't smile when the passengers were boarding or getting off the plane, and the passengers initiated greetings, not the staff. To me this was an odd experience to have with any flight/airline. I had a bad experience booking this flight. The price didn't solidify until late hours into the night. Ever time I purchased the ticket, I either received a denial email or an error because the price has changed, but it was never reflected on the flyfrontier or kayak websites until way after midnight on the date of travel. This caused me anxiety and irritation with the websites. Then I noticed a mishap with my name on my voucher as I went to check in, it was incorrect. When I proceeded to correct it, Frontier had no easy, let alone free, way to remedy it. I couldn't correct my name without a $75 charge, I couldn't cancel my voucher to repurchase it with the correct name without a $100 charge, because it was too close to departure. Then calling frontier was nearly impossible to remedy the situation with a human. It's already difficult to want to choose frontier because of all the upcharges, but you feel kinda trapped into doing so because it's the more affordable airline.

Our flight was cancelled. They could do nothing to help us get another flight that was timely. Because the first leg was cancelled we were unable to get to our connection. We had to book on an entirely different airline for today. So we spent more money, lost a day of vacation and will never fly Frontier again, so the 'we are sorry, here is $100 credit' is a joke since we won't be flying on Frontier.

I liked the turn-style feature at gate 209B at LAX. Very efficient process. The gate staff also made several, clearly directed announcements so I felt very informed.

Seats are uncomfortable but price is good. Guess I can put up with misery for four hours.

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

Information on your arrival and departure airports

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