Find cheap flights from Colorado to Illinois

Find cheap flights from Colorado to Illinois

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Boston (BOS)
Illinois
Thu 5/13
Thu 5/20
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Good to know

Low season

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

High season

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

Average price round-trip

$403(avg. price over the last 2 weeks)

Good deal round-trip

$83or less

Good deal one-way

$48or less

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Top 5 airlines serving from Colorado to Illinois

Scores according to KAYAK customer reviews

7.9
Delta
Overall score based on 29,252 reviews
8.1
Boarding
7.8
Comfort
8.5
Crew
7.8
Entertainment
7.5
Food
Airline reviews

Cons: "100% as always.. delta has never disappointed! Keep up the good work guys"

Cons: "Delta.... they’rrrrrr Grrrreaaate!"

Pros: "Most of the crew was great with the exception of curbside check-in in Denver."
Cons: "Curbside needs to stop chasing cash tips and do their jobs. If they focused on that tips would be easy to come by. The curbside attendant that took my bag didn’t even bother to check my id. He asked me my name and asked where my destination was. I told him Cincinnati as a layover then LaGuardia where he said that was wrong. He then proceeded to print a boarding pass that wasn’t mine and load my bag into the conveyor. Not 5 mins go by when I realize what happened I wound up having to go to special services to rectify the situation. Which ultimately consisted of me waiting another hour in LaGuardia to get my bag. Please delta have these curbside handlers actually want to do their job and stop chasing cash tips."

Pros: "Good"

Pros: "Flight left on time and landed on time"

Pros: "Quick flight...ahead of schedule"
Cons: "Cheese It’s are boring...miss the snack mix"

Pros: "Flight was delayed for more than 3 hours."
Cons: "Could have left on or close to schedule."

Cons: "Choice of healthier snack"

Pros: "Nothing spectacular."
Cons: "The headrests won’t stay up. And it’s hot."

Cons: "Have rhe right to carry at least one luggage per person at no cost. Besides carry on and personal item. Tickets prices and luggage costs are extremely expensive."

Pros: "Staff from Check in to aircraft very pleasant. Snack choice in Coach impressive."

Cons: "Uncomfortable chairs for a three hour flight"

Pros: "see above"

Pros: "Very friendly gate attendants helped us fix the problem that our frequent flyer number had not been entered on the boarding pass. This may have been because of the booking co., Just Fly."
Cons: "Would have liked more seat options, like when I book on Delta's website. Didn't have enough advance warning."

Pros: "Check in Denver super helpful Gate staff hustled to turn around flight Flight crew excellent"
Cons: "Flight delayed, almost missed international connections"

Pros: "Boarding, friendliness of staff"

Pros: "Everything was easy and smooth."

Pros: "Short flight"
Cons: "In SLC they boarded by row numbers and not zones. Weird..."

Cons: "Engine problems-2 hour delay"

Pros: "The fact that there was a screen for movie selections and a charging port for my phone and the flight attendants were super nice"

Pros: "Good flight crew"
Cons: "Delayed due to mechanical issues. For 3 hours. No offers for free drink or wi fi. When we finally land we were on the runway for half hour."

Pros: "Everyone was fairly friendly"
Cons: "Cramped foot room"

Cons: "Bags never arrived at the listed baggage claim. After 45 min, I saw bags on a different claim station and I notified everyone standing around. BUT, I filed a claim with Delta and was immediately given 2500 miles, as guaranteed!"

Pros: "After almost every airline cancelled. Delta still took me to where I needed to go with not one single problem. That pilot was amazing. I forget his name. But the plane didn't slide or anything during take off. Amazing."
Cons: "What was there not to like. We were a little bit late but I wasn't in a rush. I planned well ahead. Delta moved my flight from 10 a.m. to 6 a.m. and that was perfectly fine with me."

Pros: "Great people and crew early arrival nice passengers"

Pros: "Nothing!"
Cons: "Everything"

Pros: "Delta is great"

Cons: "The crew forgot to turn the heater on in -3°F creating a situation where the lavatory water lines froze. This caused a two hour delay which made me miss the second leg. Because I missed the second leg I was put on the very last flight out of ATL and got to spend Xmas eve in the airport."

Pros: "Crew was nice."
Cons: "The Entertainment sucked. Again I was sitting in comfort class which in theory should buy you more comfort and better entertainment. There was a ton of movies from the 90s and the same movie selection from about 6 months ago when I traveled with them. Also, what is going on, with having to use your own cell phone to watch movies on the plane? Whatever happened to the screens in the backseat of the front seat? I ended up with neck pain from trying to watch a movie on my phone. Delta has become very cheap. It is going into some serious decline."

Pros: "Nothing"
Cons: "Let me just say that I’m a loyal Delta costumer until now. The flight attendants (the two women) were an absolute nightmare. They were so rude and condescending. I was carrying with me my service dog and a bag containing an expensive medication (it couldn’t go on the top bin). Despite being in the comfort class and having the seat next to me empty, we were tight for space. The flight attendants were unreasonable and forced me to put my medication on the top bin despite the fact I had told them it was extremely delicate, that it that to go upright, and that I needed to keep it with me. They did not listen and pressured me into giving them the medication. The medication could have easily gotten broken. Thankfully it didn’t but this is no way to treat a human being."

Pros: "Was initially hoping to fly a US airline but will now look for Aeromexico first. Exceeded my expectations!"
Cons: "The layover in Mexico City was a bit long and the airport was not so great"

Pros: "What a city.. Unique for hell sure..."
Cons: "Nothing"

Pros: "Boarding super excellent! Also: Best landing I've ever experienced! Props to the pilot!!"

Pros: "Newer plane with movies."
Cons: "Airlines pack you on so tight."

Pros: "Friendly and informative flight attendants kept the passengers in reasonable spirit."
Cons: "Left nearly an hour late after confusion related to oversold seats and upgrades. The gate agent entered the plane multiple times. The landing was rough, the brakes were loud."

Cons: "I fly Delta quite often, and am usually pleased with their service, but the morning of June 23 was terrible. I got to the airport in Denver at 5:30 am for a 7:30 am flight to Atlanta, and the line to check a bag was about 40 people long. I waited 55minutes to check my bag, as they kept moving the ski priority people, and people in danger of missing their flight, to the head of the line. There were obviously not enough Delta workers on staff to process all the flights at that time."

Pros: "The moviea"
Cons: "The time of night"

Pros: "I didn't like anything because the fly leat 3 hours"

Pros: "Smooth ride. Delta got everything right from takeoff to landing."

Pros: "The flight attendants were so nice and accomadating. Even came by to refill our waters! I've never been on a flight with such friendly flight attendants!"

Cons: "Flight attendants were a little snobby and didn't treat all passengers equally, in my humble opinion (note: I was sitting in 1st class)."

Cons: "I drove 5 hours to get to the airport and unfortunately ended up delayed because of traffic and slow shuttles from parking. I arrived 1 hour before the flight, but security was so slow I didn't get to the gat until 10 minutes before arrival. There were no gate agents present and despite banging on the gateway door and other Delta agents at the adjacent gate, no one helped me. I can only surmise that they had already given away our seats, which were award tickets, GAINED BY BEING A LOYAL DELTA CUSTOMER. The gate agents were unapologetic and useless at rebooking, and I bought a ticket from Southwest instead. As i was trying to get to my sister's wedding, and repeatedly told the agents this, their behavior was particularly abominable. DELTA, YOU'VE LOST A LOYAL CUSTOMER."

Cons: "Seats too close - I'm not that tall and my knees were jammed against the seat in front of me."

Pros: "Plane was clean and staff were friendly"
Cons: "The snack options were quite average"

Pros: "Always have great experience with Delta flight attendants and staff. The entertainment on mobile phone was a really nice add-on, I had never seen before."
Cons: "Flight was delayed in taking off, waiting for connecting passengers. Plane was old, which is most Delta planes, but this one showed it. The tray table looked like it was from the 70s or 80s. Flying into Midway instead of O'hare was anticlimactic."

Pros: "Excellent customer service. That doesn't seem to happen too often with airlines. Delta has been outstanding."
Cons: "No complaints."

Pros: "on time travel care in treating my visitors from Kenya Africa"

Pros: "you still get a complimentary snack and drink"

Cons: "I had no room to move and my legs were stuck"

Pros: "Crew was nice"
Cons: "Lots of empty seats... during covid/social distancing there should only be 2 ppl in a row especially if there is room...it was crowded and not consistent with signs posted saying stay 6 ft apart"

Pros: "Nothing."
Cons: "Everything"

Pros: "We didn’t crash and die. That’s the only positive."
Cons: "Before we boarded I listened to a couple described how they always went ahead in line at boarding because no one ever stopped them. They described how they waited until group 3 was called and then went right through. While we were waiting, we watched them do it again. If you need to cram people into tiny spaces to be profitable, then you cannot allow them to make it worse by putting back their seats. I spent 90 minutes with a seat back jammed into my chest. We were ignored when handing out snacks, probably because we were invisible behind the seats pushed in our faces. It was one of the most miserable flights I’ve experienced."

Pros: "Nothing"
Cons: "Had to change our plans, and AA wouldn't give us a refund. We never got on the plane but had to pay for the tickets anyway. I'll never fly AA again."

Pros: "Everything was excellent"

Pros: "It didn’t happen"
Cons: "It didn’t happen"

Cons: "Seatings"

Pros: "Comfy seat, great entertainment options"

Cons: "You were out of earphones"

Pros: "We were allowed to board early with my father, who is disabled."
Cons: "Denver airport was a nightmare with my disabled father. We were given a “wheelchair” but no escort through a nightmarish security scene. Airport is terribly designed, lacking clear signage and navigation. TSA was a disaster and no one seemed remotely concerned about my father’s comfort or needs."

Cons: "We had 3:10h delayed..."

Cons: "Was delayed a lot"

Cons: "The flight was delayed which caused us to miss our flight in London our family was delayed for 12 hours"

Cons: "Boarding at gate a47 T2A at CDG was chaotic"

Pros: "seat was basic. prefer having tv screens in the seatbacks as opposed to using my tiny phone as a viewing screen."
Cons: "prefer having tv screens in the seatbacks as opposed to using my tiny phone as a viewing screen. only food available besides pretzel was pay food."

Pros: "The plane was super comfortable"
Cons: "Long check-in lines in Denver - there were two sky caps outside who had no line which allowed me to reach my gate in time. Otherwise I may have missed my flight"

Cons: "Try to be on time!"

Cons: "If we had access to the WiFi to watch shows earlier like United does, that would be nice."

Cons: "We are delayed 7.5 hours dues to mechanical issues with our plane and told we would have to wait or book another flight the following day. American Airlines sucks!!!!"

Pros: "The flight was on time."
Cons: "The seats are absolutely horrible. I feel crammed like a sardine in the plane. Seriously, can we adjust the seat widths and distance to the seat in front and make them a couple inches bigger?"

Cons: "I have changed flights. Been delayed 5 times now. And still haven’t left the USA."

Pros: "The crew was very friendly and accomodating."

Cons: "Poor they lost my luggage. They did not allowed me to take my suitcas whit me because the plan was too small. I never travel again whit amercan airlines"

Pros: "The jet"

Cons: "No advanced seat assignments unless we paid $100 per person?! Recently flew Delta on same equipment (A321). Delta had in-seat entertainment & adjustable head rest"

Cons: "Waited on the tarmac for over an hour before departure with very little explanation."

Cons: "There was no entertainment at all, and pretzels are gross"

Pros: "American"

Cons: "Two hour delay out of Denver, no crew."

Pros: "There was nothing to like about the way this sudden last minute cancellation was handled."
Cons: "I expected at least an offer of some kind of compensation for the inconvenience. it didn’t and hasn’t happened thus far."

Pros: "Everything went smoothly"

Cons: "Breakfast - lots of sugary items"

Pros: "We were rerouted through Philadelphia."

Pros: "Great service, friendly staff. Plenty of in-flight entertainment options"
Cons: "N/A"

Pros: "Free in-flight entertainment. Like that in-flight entertainment is available on users device, rather than screens in headrests. Staff were courteous and friendly."
Cons: "Flight delayed d/t computer glitches and problems in NC. Once we eventually boarded, we were forced to check our carryon luggage d/t lack of space."

Pros: "Good is that they sent you to Finnair to correct AA created break in service...why would they pay for it? AA is just an operator per itinerary! Why would you care if ppl get help with connections!"
Cons: "Checked in online on Finnair and automatically for the second connecting flight...and not the first -AA. So, had to check-in again for the first flight at the terminal. Board passes were printed 2 out of 3 by AA and both had errors - wrong gate for the first flight and no boarding info for the second connecting flight - just blank! AA did not provide connecting info until I found an unoccupied employee at the terminal and customer service lines were about 20 people in 2 locations I went to. The connecting info should be in the itinerary they said at customer service...nope, it was not there either!"

Pros: "Nothing"
Cons: "Broken plane, re-route and conflicting inaccurate email updates."

Pros: "Great service."

Pros: "The helpful steward"
Cons: "The bumpy ride"

Pros: "fairly comfortable, crew was helpful"
Cons: "Having to use my phone for entertainment, with no place to plug it in"

Cons: "I'm not sure where the problem was - whether with AA or Royal Jordanian, but my luggage did not make it to Amman with me. In fact, there was a whole group of passengers traveling on American from different US cities, switching to RJ in Chicago, whose luggage did not come on the flight to Amman. My advice: be sure to pack enough for a couple of days in your carryon - and don't accept an offer to check your carryon to its final destination!"

Pros: "Comfortable seats, good legroom."
Cons: "Not enough coffee for breakfast."

Cons: "This was a BA flight on an American Airlines plane. Very small crowded and uncomfortable. My husband is 6'2" and barely fit in the seat."

Pros: "The crew was awesome."
Cons: "You guys lost our luggage!"

Pros: "All good, except poor prep on food"
Cons: "As above"

Pros: "Great crew with an attention to details!"
Cons: "40 min late and a bumpy ride the whole time but good flight"

Pros: "Quick and easy boarding"
Cons: "Uncomfortable seats"

Pros: "Everything ran smoothly despite turbulence and bad weather, thanks to the crew."
Cons: "Seating is even more cramped than I'm used to, and everything outside of a drink and a biscuit is extra money."

Pros: "Nothing"
Cons: "Everything"

Pros: "There was nothing too bad other than I wasn't able to check in online bc our first leg of the flight was operated by American Airlines. But there wasn't anything that really stood out that would make me want to fly them again other than it was the best price."

Pros: "Na"
Cons: "Na"

Pros: "Very friendly and helpful crew!"
Cons: "Beverage and food was not available on a few of my flights. And neither was in seat entertainment."

Pros: "No room. Delays."
Cons: "Board me 1st."

Pros: "Crew was great."
Cons: "Doing a better job with last minute delays and connecting flights. I’m tired of lost bags."

Cons: "Complimentary ear plugs and eye mask would have been great."

Pros: "Crew was great"
Cons: "Luggage was damaged, flight was delayed multiple times, baggage took forever to retrieve (and was not prioritized properly)"

Pros: "The crew was good. Some flight attendants aren’t very personable."
Cons: "Pretzels? Really bad."

Pros: "No the crew were not very friendly at all. I was not greeted with a smile at all. My seating was horrible, I unfortunately was seated in the last row, beside the washroom. My seat would not recline. I will never locate my seat at the rear again, total claustrophobia."
Cons: "do not take the rear seat in a small airplane ever."

Cons: "The plane had some technical difficulties and after some time it was ready to go. Everyone boarded (some for the 2nd time) all luggage and carryons in place. After sitting at the gate for aboit 20 min they said the plane was not safe to fly and got everyone off. This took a while since it is a huge plane. We finally got a new plane and instead of leaving at 8:20 am we finally left Denver and arrived Chicago at 2:50 pm. Out of the 4 legs of this round trip, 3 of them were terrible."

Cons: "Late late late and no information shared about why."

Pros: "It was fine"

Pros: "Cost"
Cons: "Last row"

Cons: "No food or entertainment"

Pros: "Everything."

Pros: "Airport person with wheelchair at Denver was extremely helpful getting a disabled co-travelor from gate b85 to gate b28 in record time to catch the flight to Chicago. A BIG Thank You to the agent in charge of boarding for getting the three of us sitting together."
Cons: "The direct tv screen couldn’t be shutoff. With a plan as big as a 757 there should be a beverage cart per section of the aircraft otherwise passengers at the far end are wondering why they’re being left out."

Cons: "lost my luggage"

Cons: "The landing was terrible. I guess everyone is allowed a “opps”"

Pros: "United representatives were friendly."
Cons: "TSA at Denver was the worst I have ever experienced in all my years of flying - they closed down lanes despite incredibly long lines winding around the entire floor of of the security areas, their staff was rude and the lines moved incredibly slowly - mostly because they seemed understaffed and unconcerned with anything other than themselves."

Pros: "The flight attendant"
Cons: "United in general"

Pros: "On time for once"
Cons: "Cost of the flights + baggage"

Cons: "Flight was cold-air blowing that I could not turn off"

Pros: "Couldn't get Wi-Fi to work"

Pros: "The crew"
Cons: "The seats r too small"

Pros: "I got home safely."
Cons: "Every time I fly United they manage to screw something up. Two hour delay on the way out. 45 minute delay on the way home while they located another plane (mechanical problems) made my connection impossible. They did get me on a plane to Newark, which was also delayed. I made the connection by the skin of my teeth and a lot of anguish. My luggage did not. All in all, a very unpleasant travel day."

Pros: "Apathetic unfriendly and unprofessional personnel at ticket counter. If handicapped don't look for anyone to help. They clearly let you know it's your problem-- not their responsibility to help."

Pros: "Staff was very friendly."
Cons: "I only had 2 nights in chicago and one was completely ruined as we got in so late that the event we were supposed to attend was already finished. We also were sitting for a long time and it was very uncomfortable while waiting to take off. We didn't get any beverages after sitting for a long time and finally did once we were in the air which was 2 hours later."

Cons: "Very late."

Cons: "Boarding by zones causes passengers to have to stand longer while waiting to board, inconveniences them by having passengers seated in window and middle seats often arrive after the passenger in the aisle seat, and slows down the entire process because passengers settling into the front part of the plane frequently board and stow luggage while those seated in the back queue up behind them. Compared to boarding by row, the entire process is now one lengthy mess."

Cons: "showed up for a 5:20am flight and was told at check-in it was now 7:30... Nobody could have told me that before I woke up early, got a cab early and showed up to the airport early?!"

Cons: "Seats sucked hard no give. Cramed in like cattle"

Pros: "Snacks"
Cons: "Nothing"

Pros: "The flight was great."
Cons: "The turbulence was the worst part"

Cons: "Seemed like a newer plane that had a lot less leg room than my previous flight. I'm pretty short and I was uncomfortable."

Cons: "Was given a seat in the last row of the plane, which didn't recline. There was not enough room for my carryon cuggage and I had the lowest priority boarding. The option to upgrade was $99 each way"

Pros: "Planes are old as dirt. Flight attendants were unfriendly and unaccommodating and finally, there was a 2.5 hour world wide data transfer systems failure on the last leg of my trip. Have a 12 hour day of surgery followed by appointments. Thank you United. Your airline is a joke and I'm ditching your stupid mileage credit card. I'd rather purchase magazines with my miles than fly with you ever again."
Cons: "Absolutely nothing."

Cons: "Delayed over an hour Changed gates after our initial flight time"

Pros: "The crew was very kind to everyone and it was a very pleasant flight!"

Pros: "Did make the connection to Chicago after running to the gate-last 2 to board before cabin was locked."
Cons: "Sat on the runway for approx an hour-no wear to park. Almost missed connection. If we weren't in good shape, would never have made it."

Pros: "The crew was great"
Cons: "Late flight and plane was not parked right at terminal in Chicago so it made for a long wait to get off the plane"

Cons: "Every flight I book with United gets delayed. My flight to my destination initally was delayed by over an hour causing me to miss my connecting flight. They re-booked my flight for the next morning so I missed my first evening of my trip. On the way home my flight was delayed 5 hours, turning my travel day into a 10 hour travel day... I will not be flying with united again."

Cons: "Old huge plane. Sat in back. Awful. Didnt move for what seemed like half an hour or more before we even started moving toward runway. Then did the same thing once we landed. Chlosterphobic and awful."

Pros: "Our flight experiencedetails mechanical issues to the weather radar. The agents sent us to customer service 12 gates away but they didn't know what was going on so they sent us to another customer service desk 21 gates away. Cathy of United finally called the gate(or plane) and found out that the problem was almost fixed...a hour later."
Cons: "Above comment contains my opinion of the first leg of the flight which only got worst as the connecting flight from Chicago to Providence was delayed and the plane was too big to land in Providence which caused us to have to catch a bus from Boston to Providence."

Pros: "Departed on time."
Cons: "Small plane...every seat taken and crowded."

Cons: "The crew knew multiple people on the Hayden to Denver flights had very limited wait time to get from plane to terminal, but took forever in delivering our luggage for plane side pick up. When I asked the lady who came by to let us know of our gates, she pretty much told me, 'good luck'. I picked up my bag with 10 mins to spare to run from gate 86? to 24. I think more should have been done to accommodate. To be fair, the other lady who came by to let us know of our gates, offered to call my terminal and let them know I was on the way"

Pros: "I know it's some sort of miracle. But there was only 40 people on an airbus. We all had about 3 seats each and we made full beds for ourselves."

Cons: "Boarded and left late for many to miss connections. No real help to get to new connection both on plane and off."

Cons: "Delays! Numerous delays! No assistance to help with changing missed connections or getting a hotel while stuck in Chicago."

Pros: "A everything was fine other than..."

Cons: "Wifi didn't work"

Cons: "My flight was delayed 9 times with 9 different gate changes. I was supposed to arrive by 10PM and didn't land until 2 AM."

Pros: "Boarding back to front makes so much sense! Thanks!"

Pros: "The check in clerk took care to reprint my boarding pass so it reflects my TSA precheck status."
Cons: "The seat was stiff and uncomfortable"

Pros: "Not too much - the crew was nice."
Cons: "My flight from St. Louis to Denver did not charge me for a carryon bag. I was very surprised to be charged $50 for my carryon bag at the Denver checkin, When I complained I was presented with an incredibly rude attitude. The flight was crowded and the space was so very small and cramped. I will never fly Frontier again. Your cheaper rates are not worth the flight experience."

Pros: "Clean comfortable plane"

Pros: "The flight was delayed and seats suck"
Cons: "Everything."

Pros: "Not a whole lot- the crew wasn’t bad though. Captain flew fast to make up lost time."
Cons: "We waited until flight time for a late passenger, then another passenger complained about a seat and we had to wait for the mechanics Crew. We then needed to be bumped into the deicing line so we could take off. Nearly an hour past the origional departure."

Cons: "No WiFi - even for our HSE. Seats do not recline. Terrible turbulence."

Pros: "The staff was a well oiled machine! Very smooth overall experience! Very funny stewards! We even heard other people commenting & laughing after getting off of the flight!"

Pros: "Plane was comfortable and clean"
Cons: "Nothing"

Cons: "Flight was abnormally bumpy to the point even the crew mentioned it. I could hear the crew the whole flight chatting and bitching about Work etc"

Cons: "Disorganization with boarding process. Gate changes from that which was indicated on boarding pass, without notification. Expensive baggage/fees. No basic complimentary accommodations (snacks). Uncomfortable seats lacking ergonomic design and headrest. Small spaces for personal items."

Pros: "Breckinridge whiskey"
Cons: "Bit cramped"

Cons: "Unexpected 45$ per carry on. Horseshit"

Cons: "Same as above"

Cons: "My luggage was lost."

Pros: "Again, flight was good."
Cons: "At Denver, almost missed my flight since the gate I was supposed to board changed. And one more thing, it has been 10 years since my last flight and the hard plastic seats are something else. Since I paid for the seat, i might as well sat on the wing, would have been just as comfortable."

Cons: "Very slow getting our bags after the flight."

Pros: "The landing was good."
Cons: "$40 for a carry on? Come on now. $5 seat upcharge because "window seat"? Chairs that don't recline? You interrupt my already terrible nap so you can try to sell the entire plane your "no-black-outs" Mastercard. The cabin was much too hot, people complained and nothing was done -- adding insult to injury, water costs money. Every aspect of buying a ticket is littered with popups to upsell you to something "better" or more "exclusive". The entire experience from buying a ticket to touch-down was dehumanizing and an insult my intelligence."

Pros: "Cheap"
Cons: "Boarding was delayed by 35min and no reason was given. Bags were took 35min to arrive at baggage claim."

Pros: "Nice people around me! Crew members more concerned about selling drinks than offering anything!"
Cons: "Left late! No compensation! Little concern from crew except to SELL drinks! After arriving it took a really long time for our luggage with no explanation!! Did it have to do with a "door problem" that caused our delay! Need to share more and be more upfront!!!"

Pros: "Time enough to have a real meal."
Cons: "Spending 5 plus hours at an airport waiting for another flight."

Pros: "Price, timeliness, condition of the plane."
Cons: "The whole "buy your seat" and "buy your luggage a place on the plane" remains annoying. Similarly, the website gets confusing as you click through all the upsell options."

Pros: "No leg room. Seats do not recline. Only permitted 1 purse and all else is an extra fee. Extra fee to sit beside your loved one. Not really a good value."

Pros: "Crew was friendly"
Cons: "- They charge you extra for any tiny bit (seats, bags, ...). Makes the flight much more expense than what they tell you initially. - Seats are very uncomfortable and only have a tiny table - Unless you buy drinks, we only got water once during a +4 hours flight. - Flight took considerably longer than scheduled."

Pros: "It was over an hour delayed after we boarded"

Pros: "pre assigned seats, more leg room on A321 than Boing 737, clean cabin"
Cons: "zone 4 boarding"

Pros: "I was very surprised at all of the small things and extra charges that you had for the flight. For example, even just paying for a soda on board I thought was a little overboard. And then once my flight was canceled they were of no help on rescheduling my flight and were not able to find another frontier flight for four more days. Myself and others were left to reschedule our own flights without any repayment of the difference in ticket price. I will not fly this airline again I caution everyone else at the lack of customer support and professionalism ."

Pros: "The gate agents were nice as the higher ups were lying to them"

Cons: "2 hours on hold to speak with a human. Then, no options to get back to St. Louis until 4 days later."

Cons: "That there is extra cost for everything. Flights are not that cheap. So please do not use doublespeak in how failing to provide the smallest amenity is saving me money. All of it is on flight and people are serving. Not saving me money but your profits increase at cost of goodwill"

Cons: "Didn't get a free drink, no inflight entertainment. But this is to be expected with a budget carrier."

Pros: "On time"
Cons: "Bag fees are vague and expensive"

Pros: "Okay. Red eye flight to St. Louis. Managed to keep it cheap - but Frontier you have to pay for all the frills. You have to wear your suit on the plane to avoid paying for carry on."

Pros: "Flight was still comfortable, considering we had to fly over a lighting storm."
Cons: "the price for the trip does not include that you have to pay for Carry-on, and seat assignment, which is an odd expense to passengers. Especially for shorter trips with the round trip the carry on charge would equal up to at least $60. Which would equal to another airline who is comparatively better especially because those airlines aren't worrying about charging the customers for every single thing. So even though I comparison shop for my ticket, by the time I paid for these additional fees, I could have purchased a ticket from another airline for less money."

Pros: "Crew was knowledgeable, courteous and professional. Flight ran right on time."
Cons: "Seats (17C and 17D) were not very comfortable (minimal cushioning on seats and backs, no cushion on arm rests, and seats do not recline). Also, there were two pieces of used gum in my seat back pocket (yuck!)."

Pros: "price reasonable"
Cons: "this was the most uncomfortable seat I have ever sat in. the upholstery was so thin, no head support , no leg room, ridiculously small tray table paying for a soda??? and then having a choice to tip"

Pros: "I submitted a review a few days ago."

Pros: "All airline employees were pleasant and professional."
Cons: "Not enough leg room."

Cons: "Staff was rude. Plane was crowded. The only thing without an extra charge was a small cup of water."

Pros: "Just not a good airline anymore. The seats are so uncomfortable. Would never take Frontier on anything longer than a two hour flight. They were delayed 45 minutes. Wasn't given the option to pick my seat so ended up in the 41st row "window" although there is no window in that row. No more directv, so entertainment is no longer. No leg room. Just a bit disappointed and not crazy about their makeover. I guess they had to do something drastic to stay in business but I will only fly them as a last resort."

Pros: "Friendly; clean; efficient"
Cons: "Bit of turbulence but not the airlines fault"

Cons: "Expensive, uncomfortable, no food or drinks"

Pros: "The 2nd leg of the flight the worker was able to get me a window seat"
Cons: "I didn't like the surprise $60 fee for carry on bags"

Pros: "it was a great trip."

Pros: "That I got home safe and alive."
Cons: "My flight was delayed on my way to Denver by about an hour. I was delayed getting home by OVER 2 1/2 HOURS! And one and a half of those hours was in the tarmack due to gross negligence. I talked to my friends some of which are travel agents and all said the same. That Frontier is a nightmare and to never deal with them. From now on I won't."

Pros: "Boarding passengers with carry-on first."
Cons: "Having to pay for carry-on luggage and seats - false advertisement of lower airfares. No free drink service."

Pros: "We had service dogs, and the entire staff was willing to work with and accommodate our needs. They were super friendly and we left knowing more than a few smiles were shared. Thank you."

Cons: "I didn't like the $1.99 for soft drinks"

Pros: "What is the point of assigning passengers zones if they aren't going to use them for boarding. Asking all zones to board as once created chaos and tension in the line. It was unnecessary and unorganized. Waiting for luggage was excruciating. I've never waited that long for my luggage, and the only reason why I waited for luggage was because Frontier charges more for passengers to carry on than to check luggage. I will try to avoid this airline at all costs in the future."
Cons: "See previous comments."

Pros: "One crewmember in particular was very pleasant and helpful."
Cons: "We were squeezed in like sardines and the mini tray tables are a joke, actually left with the person next to me about them. Seats are hard and uncomfortable, and do not tilt back"

Cons: "Constant meaningless delay’s."

Pros: "The gate agent was tremendously kind, friendly and helpful."
Cons: "The cabin crew were the opposite. The plane was FREEZING. When asked to turn the heat up (twice) was told it was warm in the back (I was in the front) so it needed time to heat up. Asked again later and nothing changed. I was not the only freezing passenger. - hats coats scarves hoods everywhere"

Pros: "Paying $35 to “upgrade” to basically any other airlines regular seating"
Cons: "Literally everything."

Cons: "the flight attendants could have acted in a professional manner not like they were ten years old"

Cons: "There was a power outage and the Spirit representative told everyone that the plane wouldn’t leave anyone behind. Once we got through security at to the gate they said the plane left 2 minutes before. No announcement was made. I could’ve saved time checking in online but the server went down (seemed unrelated) and the site is incredibly confusing. Its hard to describe but all the employees seem really inexperienced and it’s hard to get good information. So unreliable"

Pros: "The people were friendly and you can't beat the price."
Cons: "The trip out was late, but that was because of weather, so no biggie. But on the return trip, we sat on the tarmac for over an hour because of "boarding gate problems". There was a loud beeping noise for the entire hour we waited and only one announcement was made to explain the situation. At some point we were finally allowed to exit the plane onto the runway (not the boarding platform)."

Pros: "Great deal!"
Cons: "A little cramped"

Pros: "Crew was very nice"
Cons: "6 hr delay"

Pros: "excelente"

Pros: "Arrived 30 minutes early"
Cons: "Rough ride, rough landing"

Pros: "It was on time. Very good overall. 4.5 stars. Can't get the stars to show correctly"
Cons: "The plane itself was rattling the overhead storage bins in the descent. In The ascent and descent, a little bumpy now and then."

Cons: "no wifi"

Pros: "Loved our pilot! He had a fantastic personality and made us feel at ease."

Cons: "My flight was delayed 3 hours on the way out to Denver and they completely cancelled my flight without notifying me. Was not reimbursed. Will never fly spirit again."

Pros: "Nothing"
Cons: "I scheduled to fly Denver -> Chicago -> Fort Lauderdale. They cancelled my flight and put me on a terrible flight (Denver -> LA -> Fort Lauderdale) without telling me. So I cancelled their new itinerary for me and flew southwest. Spirit sucks."

Pros: "You are definitely not inexpensive. I will do everything in my power to not use your service again. Your luggage policy is abominable. No thank you!!!!"

Pros: "It was safe"
Cons: "It was expensive and uncomfortable"

Cons: "Wouldn't let us change or cancel our flight a couple days in advance, even for a death in the family."

Cons: "The charge for bags is extremely high. The cost of a soda on the plane is $3."

Pros: "WE GOT CANCELLED"

Pros: "Nothing"
Cons: "Everything"

Pros: "Service was fine."
Cons: "I didn't know about the baggage charge. I probably won't fly Spirit anymore. I paid more for my bags than my ticket. Let Kayak know your baggage rules so they can advertise this with the fares."

Cons: "During a difficult weather situation, Spirit was absolutely useless and left us stranded for a week. With storms on the East Coast, Spirit cancelled flights two days in a row (as did all other airlines). However, with Spirit, the website was useless for rebooking ourselves, and there were so few representatives at the airport and to reach a rep on the phone that we waited several hours just to be able to rebook at the airport. In the end, Spirit could not get us on another flight out for 7 more days. Causing extreme additional expense to me and my travel partner. I will never risk flying Spirit again."

Cons: "My flight was 2 hours late to take off and we ended up in Detroit instead of Chicago. Passengers said they got $50 back but I never did."

Pros: "Nothing"

Pros: "Friendly employees"
Cons: "Spirit canceled our flight and their only solution was refund or wait 3 days until they could get us home. Had to spend thousands to rebook to get us home the next day on another again. Never again."

Pros: "not much poor cust. service"
Cons: "lack of service. & communication"

Pros: "Nothing"
Cons: "Had to purchase another ticket home because kayak"

Cons: "$9 Fare Club. Still trying to figure out what it means???"

Pros: "funny stewardesses"
Cons: "everything else. at least i'm home in one piece."

Pros: "Price was good."
Cons: "Rough landing, sounded like whole plane shook. Not much leg room at all. Very cramped comparably with previous flights I've had."

Pros: "The seats themselves were comfortable."
Cons: "But, the seat was too close to the one in front of me. I'm 5'7" and had barely enough room for my legs, and my husband is 6'2" and had to push his knees to straddle either side of the seat in front of him."

Pros: "Price"
Cons: "2 out of 4 flights had boarding delays."

Pros: "I like the colors and the staff"
Cons: "Just about everything else"

Cons: "Flight didn't happen because the Spirit flight from Chicago to get to Denver left 15 min early on 10/21. I never got to Denver. I was in security at o'hare at 12pm. Got to the gate at 1205 and the plane had already taken off."

Pros: "Low airfare. A320 has good seat lighting."
Cons: "Seat backs were so thin, I could feel people using the pocket on the back. Seat belts were installed wrong? I had to put a twist in the belt to buckle it."

Pros: "Left early and arrived early which doesn't happen very often."

Pros: "Nothing"
Cons: "Cramped seating."

Pros: "Nothing"
Cons: "Everything"

Cons: "Flight was delayed,"

Pros: "It was fine. I don't like how Spirit charges for take on bags and all snacks."
Cons: "It was overall fine."

Pros: "I eventually got to my destination."
Cons: "Hidden bag fees and delayed fights"

Pros: "Nothing"
Cons: "Delays, seating, costs, baggage."

Pros: "My flight was canceled indefinitely the night before the flight a) without any heads up and b) due to thunder and lightening, it was the ONLY 6am flight canceled. It's unacceptable to conduct business this way, and to no accomodate as a result. I was left completely screwed over to pay ASTRONOMICAL fees to get home for a family wedding I was in. To rub salt on wounds, Spirit's employees (very tall thin man, young to middle age, on the left far desk) along with one other, were rude, unhelpful, condescending, unprofessional, the list goes on. Spirit just lost a very loyal customer who always stood up for the company name. I expect and deserve better. Guess I'll go to Frontier."
Cons: "My flight was canceled indefinitely the night before the flight a) without any heads up and b) due to thunder and lightening, it was the ONLY 6am flight canceled. It's unacceptable to conduct business this way, and to no accommodate as a result. I was left completely screwed over to pay ASTRONOMICAL fees to get home for a family wedding I was in. To rub salt on wounds, Spirit's employees (very tall thin man, young to middle age, on the left far desk) along with one other, were rude, unhelpful, condescending, unprofessional, the list goes on. Spirit just lost a very loyal customer who always stood up for the company name. I expect and deserve better. Guess I'll go to Frontier."

Pros: "Flight was on time"
Cons: "It's so expensive to check in your luggage compare to other airlines"

Pros: "Nothing."
Cons: "Everything. Rude staff, terrible."

Pros: "The pilot got the plane to Chicago over 30 minutes early."
Cons: "Spirit allows passengers to bring a purse for free everything else is an additional charge. The plane was really dirty."

Pros: "They were friendly and entertaining."

Pros: "The staff Was very kind"
Cons: "It's not to confortable"

Cons: "Nointernet."

Read more about Delta
COVID-19 information

Safety measures for airlines flying from Colorado to Illinois

Airlines flying from Colorado to Illinois 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 Colorado to Illinois

Mandatory masks

Masks required on board, masks provided on flights from Colorado to Illinois

Social distancing seating

Middle seats unavailable to book on flights from Colorado to Illinois

Pre-flight testing

Testing for antibodies, testing for symptoms for flights from Colorado to Illinois

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