STL - DEN

$78 Find Cheap Flights from St. Louis to Denver - Compare and Save

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 8/19. 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 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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Everything you should know

Cheapest round-trip
$141
Typical prices: $367-$183
Frontier
Wed 7/1Wed 7/8
STL - DEN • Non-stop
Cheapest one-way
$78
Typical prices: $114-$193
Frontier
Wed 8/19
STL - DEN • Non-stop
Advice from real travelers
AI-powered summary based on content written by travel experts. AI can make mistakes.
Southwest free carry-on adds value, but checked bags now cost extra.
Frontier Premium Bundle adds legroom; United Economy Plus offers up to 6 inches more.
Expert advice
Expert advice
Expert advice
Expert advice
Nonstop flights
You can fly direct with Frontier, Southwest and United Airlines. Average duration is 2h 19m
Direct flights
Direct flights
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+1
Direct flights
Direct flights
+1
When to book
in advance
Our data shows that travelers who book at least 2 weeks in advance save around 22% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
Cheapest • 27% price drop
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
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KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to Denver!
Flight Deals
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Flight Deals

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

Wed, Jul 1 - Wed, Jul 8
Frontier Logo
8:08 pm - 9:44 pm
STL
-
DEN
2h 36mnonstop
Frontier Logo
4:10 pm - 7:23 pm
DEN
-
STL
2h 13mnonstop
$141Frontier
Thu, Aug 20 - Tue, Aug 25
Frontier Logo
8:08 pm - 9:44 pm
STL
-
DEN
2h 36mnonstop
Frontier Logo
4:12 pm - 7:23 pm
DEN
-
STL
2h 11mnonstop
$142Frontier
Wed, Jul 1 - Wed, Jul 8
Frontier Logo
8:08 pm - 9:44 pm
STL
-
DEN
2h 36mnonstop
Frontier Logo
4:10 pm - 7:23 pm
DEN
-
STL
2h 13mnonstop
$143Frontier
Tue, Aug 25 - Mon, Aug 31
Frontier Logo
3:33 pm - 11:53 pm
STL
-
DEN
9h 20m
1 stop
Frontier Logo
4:12 pm - 7:23 pm
DEN
-
STL
2h 11mnonstop
$145Frontier
Tue, Jul 28 - Mon, Aug 3
Frontier Logo
8:08 pm - 9:44 pm
STL
-
DEN
2h 36mnonstop
Frontier Logo
4:10 pm - 7:23 pm
DEN
-
STL
2h 13mnonstop
$146Frontier
Wed, Sep 2 - Sat, Sep 5
Frontier Logo
8:08 pm - 9:44 pm
STL
-
DEN
2h 36mnonstop
Frontier Logo
4:12 pm - 7:23 pm
DEN
-
STL
2h 11mnonstop
$150Frontier
Tue, Jul 21 - Tue, Jul 28
Frontier Logo
8:08 pm - 9:44 pm
STL
-
DEN
2h 36mnonstop
Frontier Logo
4:10 pm - 7:23 pm
DEN
-
STL
2h 13mnonstop
$156Frontier
Tue, Sep 1 - Tue, Sep 8
Frontier Logo
8:08 pm - 9:44 pm
STL
-
DEN
2h 36mnonstop
Frontier Logo
4:12 pm - 7:23 pm
DEN
-
STL
2h 11mnonstop
$157Frontier
Tue, Sep 1 - Sun, Sep 6
Frontier Logo
8:08 pm - 9:44 pm
STL
-
DEN
2h 36mnonstop
Frontier Logo
4:12 pm - 7:23 pm
DEN
-
STL
2h 11mnonstop
$159Frontier
Tue, Sep 1 - Sat, Sep 5
Frontier Logo
8:08 pm - 9:44 pm
STL
-
DEN
2h 36mnonstop
Frontier Logo
11:42 pm - 5:30 pm
DEN
-
STL
16h 48m
1 stop
$160Frontier
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.

How much is a round-trip flight from St. Louis to Denver?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from St. Louis to Denver departing in July.

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 Friday, 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 October, where tickets cost $175 (return) on average. On the other hand, the most expensive months are June and May, where the average cost of round-trip tickets is $337 and $298 respectively.

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 22% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 6 weeks before departure.

Expert advice

Expert advice for your flight from St. Louis to Denver

 
AI-powered summary based on content written by travel experts. AI can make mistakes.
KAYAK teamed up with top travel experts to share the best tips for your journey.
Our travel experts
Stefanie Waldek

Stefanie Waldek

Expert on Frontier and United Airlines

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.

Blane Bachelor

Blane Bachelor

Expert on Southwest

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.

Yulia Denisyuk

Yulia Denisyuk

Expert on STL

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.

Harriet Baskas

Harriet Baskas

Expert on DEN

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.

Good to know

Low seasonJanuary
Cheapest flight$78
Best time to beat the crowds with an average 17% drop in price.
Most popular time to fly and prices are also 10% 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 5 days, the lowest price for a flight from St. Louis to Denver was $78 for a one-way ticket and $141 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, Alaska Airlines, Delta, and JetBlue 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 MAX 8 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?

    SkyTeam, and Star Alliance are the airline alliances operating flights between St. Louis and Denver, with SkyTeam being the most commonly used for this route.

  • 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 $326 and an overall rating of 7.9, Southwest is the most popular choice. Delta is also a great choice for the route, with an average price of $326 and an overall rating of 7.9.

  • 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 $167 or less one-way and $301 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

Frontier,Southwest,United Airlines

Frontier,Southwest, +1 more

Tuesday

Frontier,Southwest,United Airlines

Frontier,Southwest, +1 more

Wednesday

Frontier,Southwest,United Airlines

Frontier,Southwest, +1 more

Thursday

Frontier,Southwest,United Airlines

Frontier,Southwest, +1 more

Friday

Frontier,Southwest,United Airlines

Frontier,Southwest, +1 more

Saturday

Frontier,Southwest,United Airlines

Frontier,Southwest, +1 more

Sunday

Frontier,Southwest,United Airlines

Frontier,Southwest, +1 more

See more direct flights

Direct returns

Denver Intl to Lambert-St Louis

Monday

Frontier,Southwest,United Airlines

Frontier,Southwest, +1 more

Tuesday

Frontier,Southwest,United Airlines

Frontier,Southwest, +1 more

Wednesday

Frontier,Southwest,United Airlines

Frontier,Southwest, +1 more

Thursday

Frontier,Southwest,United Airlines

Frontier,Southwest, +1 more

Friday

Frontier,Southwest,United Airlines

Frontier,Southwest, +1 more

Saturday

Frontier,Southwest,United Airlines

Frontier,Southwest, +1 more

Sunday

Frontier,Southwest,United Airlines

Frontier,Southwest, +1 more

See more direct flights

Reviews of the top 4 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.
7.9
SouthwestOverall score based on 4235 reviews
8.0Comfort
8.6Crew
7.0Food
7.5Entertainment
8.1Boarding
Airline reviews

there were two flight attendants that were up front...that were the best! They get KUDOs for making my trip only fantastic. Tell them Jeff said that!

10.0 ExcellentAnonymous, Jun 2026
OKC - LAS
Read more Southwest reviews

there were two flight attendants that were up front...that were the best! They get KUDOs for making my trip only fantastic. Tell them Jeff said that!

OKay. I sat in the back of the plane and it was really loud between babies and little kids, and adults who.like to talk a lot and loudly most of the flight.

Flight coming out of Buffalo was delayed, so we had to be rescheduled on another flight from Baltimore to Phoenix which means we had a long layover and got home 3.5 hours late. Shuttle to parking stopped at 10pm, so we had to pay for an Uber to the parking lot and got charged an extra day of parking since it was after midnight. Not the best experience. Long day!

Was fine, delayed and feels like southwest is always late

I don't know why flying out of Sarasota requires two plane changes.

The first time I flew in the extra legroom section. It was difficult to notice a difference. I had bad luck with my neighbors. The crew was okay. Southwest has reduced the live TV options.

The flight was smooth. The Southwest experience has degraded overall, but this one was okay.

No gluten free snacks. Seats felt worn or bare bones even though it was a new 737 MAX 8.

One major problem that was very unprofessional and uncalled for. Plane landed and we had to wait 20 minutes to get off the plane since they were waiting for someone to come to the gate to drive the jetway. Southwest couldn't have someone available and waiting for the plane to land? Is there only one person in Hobby airport who knows to drive the jetway? Was he at lunch? In the bar? Uncomfortable and uncalled for!

We waited in the airplane for over 45 min for a southwest employee to make the flight. This cause over half the plane to miss their connecting flight in Denver. When we confronted the desk upon arrival, they told us the only flight they had was the next day leaving at 8:50 pm!!! Or they offered to get us to Burbank or LA, but after that we were on our own to get back to Santa Barbara. I paid for a flight from sba to bna bna to sba. My re entry into mom mode has been 💯 rough because of southwest mistake with my flight. And now I’m leaving to Reno tomorrow for a vballl tournament and just discovered that my leg in Vegas has me and my 3 kids on a stand by flight even though I had booked these ticket last year November!! Do better southwest!

Only beverages were offered to first class and I thought the flight attendant could have also served the Delta Comfort as well instead of sitting down and staring at her phone and walking past all of us to the back of the plane to charge her phone more. There was a complete lack of turbulence and was safe enough for flights attendant to walk around in the front of the plane, collect trash and serve a few people water and turn off the seat belt light. Also didn’t enforce people putting their seats into the upright position and allowed two passengers to remain reclined during landing. They seemed out to lunch completely. Usually my experience on Delta is much better.

Long story short, it was one of the better flight experiences I've had in some time when compared with other airlines.

Flight was great! This flight from Atlanta was even better than when I paid for Comfort from SNA to Atlanta.

Connection flights should be spaced out farther because too close I missed my connection.

Definitely a southern flavor. Cordiality was evident even though no drinks or snacks were served.

On time! There were plenty of airport employees who were able to keep us moving in the right direction. The crew on the plane were professional.

Left /arrived on time. Decent seat space. Like the wifi/plugs and entertainment. Windows and tray table were kinda gross. Attendants didn't start snack service til 40mins before landing. Two rows before us, captain came on to say there's turbulence and recalled staff to seats. So, no drink/snack. Later, attendants didn't stop to see if we had trash nor even look our way. Felt invisible! Almost all pilot announcements were not only unintelligible, but so quiet. We had no idea what she said.

Average seat comfort, a drink and chips were provided, early boarding because we checked a carryon at the gate was nice. Ticket pricing shenanigans, including fees to pick a seat, check a bag, and get food onboard - evidence the industry is reinvigorating last century’s strategies- destroys the experience before one ever arrives at the airport. It’s difficult to recognize any value or sustain loyalty in the end-to-end process making air travel more drudgery than pleasure.

Gate agent was unhelpful for handicapped boarding. Flight attendant seemed untrained.

No service flight that took 5 hrs and a stop at an unscheduled airport. Crew and pilots did their jobs

Read the fine print. This was my flight home. I booked my flight for the quickest way home. Had a carry-on and a personal item. Same as my outbound flight. Apparently I needed to pre-pay extra for my carry-on. When I checked in, I was told that I had to check it. I said I’ll pay for it, and was told that this wasn’t an option anymore. They said I still had to pay $50 to check my carry-on. I told them I’ll pay whatever to just carry it in as intended. I was not allowed, so eventually I paid $50 to check my carry-on under a plane that was half full, with overhead compartments that were even less full. My white carry-on suitcase was practically destroyed getting from Idaho falls to Denver to Orange County. The low price air fair was a bait and switch. Got me to the gate, made me pay extra, then didn’t even allow me to pay for a carry on. Not to mention that I paid the $8 for WiFi that didn’t work. All to get my suitcase destroyed. I don’t think I’m going to even keep my Untied mileage plus membership and card. Apparently, membership does not have its privileges for this one.

I flew from Santa Fe to Denver to catch a flight to London and the transfer of my luggage on arrival at Denver to the London flight worked perfectly. The crew on the ground and on board for the London flight were so friendly and efficient.

Late- that’s what United does best. Missed my connection, rebooked to a flight 17 hours later and had to spend $500 on a hotel. What did I get? A $15 meal voucher. What can you get in an airport for $15. I hate United so much.

It was good overall except from Omaha to Denver when flight a was a repeatedly delayed apparently due to some issue at Denver. Communications could have been handled better. I had to board then deboard with luggage and board again

Booked through Kayak Business, had a seat in middle and towards back due to booking rate, not comfortable.

They told us yesterday APR21st that they were cleaning the plane and we got delayed. After that they said they didn't had any crew for the flight so they cancelled the flight till next day.

The flight crew on this leg of my trip was very friendly and pleasant. Every one of them was humorous, as well as helpful and accommodating. This group was BY FAR the best crew I’ve flown with. They deserve kudos.

The entertainment options on the seat back video boards were nice.

The boarding process was straightforward. One pertinent observation regarding all boarding procedures is that if an individual requires assistance or possesses a special status and is part of preboarding, it is advisable to limit the number of passengers who can preboard with them, rather than the entire, sometimes large, companion groups. The seats are uncomfortable, and the entertainment options are significantly inferior compared to other airlines. During the snack service, I requested an additional bag of snacks, but my request was denied. Initially, the flight attendant agreed to my request.becoming a strange accurate moment. The flight duration was four hours.

I had a cancelled flight because of technical issues going to my destination, and a delayed flight coming home. All told it wasn’t a total bust.

There weren't enough employees at check in took awhile to get bags checked. There wasn't a wheel chair for me, I was sent to someone who turns out to work for a different airline, if My flight hadn't been delayed I probably would have missed my flight as it was, by the time I arrived at my gate, they started boarding in about 15 minutes. I don't know who took me to my gate, definitely was not the normal people who take passengers to the gate. I'm guessing she may have been in a management position. I wish I knew her name, she went beyond to help me. With that said everyone was kind, and were doing the best they could. So, I choose to say it was an Adventure, stressful start, but good. In the end went well. The situation was not only difficult for passengers but the employee's.

The staff at the check in counter was so rude. Made you feel Incompetent

Frontier scheduled a 40 minute connection in DEN. What they failed to mention was that they “close the doors” 20 mins prior to departure, which means you only have 20 mins. Not enough time. Possibly against DOT regulations. Filing complaint.

Flight was scheduled at 9:40pm. Got delayed to 10 am, the next day. crazy

The bag check, flight check-in, and onboard experience convinced my wife and me that we will actively go out of our way to avoid flying Frontier Airlines in the future. At bag check, we were informed that check-in could only be completed via the Frontier mobile app. Unfortunately, the app was extremely frustrating—sending us through repetitive, confusing loops that repeatedly forced us to decline add-on services with nearly every click. While most airline apps upsell, this one felt intentionally exhausting. As the process dragged on, we became genuinely concerned that my phone battery would die before check-in could be completed. We approached the bag check staff—who were standing together talking—and explained both our frustration and our predicament. They laughed. Later, my wife described the interaction as “gaslighting,” which felt accurate. We were then informed it would cost $25 per person simply to have our boarding passes printed. From that point forward, the tone of the experience was consistently hostile. The bag check employees were condescending and combative, behaving more like bullies than customer service staff. Unfortunately, that same attitude continued onboard. One flight attendant argued with me when I attempted to stow my backpack in the overhead bin. I explained that we had each paid $75 to check our bags specifically so we would not need to use carry-on space and could have adequate legroom. She demanded to see my ticket, pointed out that it said “no carry-on”—which I acknowledged—and I reiterated that this was precisely why we paid to check our bags. Her response was, “I don’t make the rules.” She then walked away, but not before asking if I “truly wanted to fly back to Chicago today?”—an unnecessary and unmistakable threat. It is also worth noting that despite booking our tickets together in the same transaction, we were not seated together. Upon our return to Chicago—where we could once again sit together—we compared onboard experiences. We both remarked on how unhappy the flight attendants appeared and how each of us was separately asked whether we would like to purchase a beverage. We declined. At no point was water mentioned as an option, leaving us with the clear impression that even water came at a cost—or that complimentary water, if available at all, was deliberately left unmentioned. Overall, the experience was shocking and deeply disappointing, but it was also a profound learning experience—one we will not forget and will not repeat. -Steve

Plane was hot and miserable and the crew was rude!

12 hour delay required getting on and off plane 3 times - would have at least liked to have been offered a snack or drink

They didn’t offer a water, even after I asked

It was an early flight and most people napped/slept and the crew let us which was nice.

More inflight connection. And leg space is horrible. And the paying for baggage I'd ridiculous!!!

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

Other airlines flying from St. Louis to Denver

Flights from the other most popular airlines that fly from St. Louis to Denver according to KAYAK users. Prices are the lowest found on KAYAK over the last 7 days. Price and availability are not guaranteed.