Find cheap flights from Illinois to Denver

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Find cheap flights from Illinois to Denver

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Round-trip
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Boston (BOS)
Denver Intl
Tue 5/11
Tue 5/18
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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 14% increase in price.

Average price round-trip

$175(avg. price over the last 2 weeks)

Good deal round-trip

$77or less

Good deal one-way

$45or less

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Top 5 airlines serving Illinois to Denver Intl

Scores according to KAYAK customer reviews

7.9
Delta
Overall score based on 29,242 reviews
8.1
Boarding
7.8
Comfort
8.5
Crew
7.8
Entertainment
7.5
Food
Airline reviews

Pros: "Delta is doing a great job keeping everything calm and clean during this pandemic!"

Cons: "Nothing all excellent"

Cons: "It was great! Nice job Delta !"

Pros: "Christina brown was amazing at gate"

Pros: "The staff at Delta are always friendly and helpful and they were able to squeeze me onto a very full flight."

Cons: "It was a Great flight. I always enjoy flying Delta"

Pros: "The crew was great and the free entertainment was great"
Cons: "Bring back pillows and blankets especially on red eyes out of Anchorage"

Pros: "Love the fact that the head rests move to support your head better."

Pros: "The seat was great, I wish all seats on the plane were that comfortable"
Cons: "Nothing, everyone was great"

Cons: "No meal option and my video screen volume did not work"

Pros: "Boarding was easy."
Cons: "I am 6' 1" tall and weigh 220, so not out of the ordinary and I felt like I was stuffed into a sardine can."

Cons: "Better screens for in-flight movies. More legroom or upgrade options."

Pros: "Entertainment"
Cons: "Boarding at JFK.Always messy"

Pros: "Boarding was quick"
Cons: "No entertainment, plane was small"

Cons: "At least one hour late"

Pros: "Delta cramps people into these planes and forces you to put your bags under a seat because they stuff at the overhead spaces. They nickel and dime you for every single thing. There was even one person I saw who had to pay for his headphones to listen to the onboard entertainment. I think Delta should quit being so cheap with the profits they make and give it back to your flying customers. It borders on gouging."
Cons: "Delta cramps people into these planes and forces you to put your bags under a seat because they stuff at the overhead spaces. They nickel and dime you for every single thing. There was even one person I saw who had to pay for his headphones to listen to the onboard entertainment. I think Delta should quit being so cheap with the profits they make and give it back to your flying customers. It borders on gouging."

Pros: "Entertainment choices were excellent, many new movies available, so I was able to see movies is been meaning to watch. There were drinks available."
Cons: "The air vents barely trickle out any air anymore. No relief to be had. Airline crews say hi and goodbye but that doesn't make them friendly."

Pros: "I liked the cookies and juice. The interactive screen to watch something. The cleanliness. The price. On time. The service. Thank you. The excitement of flying."

Pros: "We boarded close to on time, no hassles. Allowed my husband and me (retired military) to board early, thank you."
Cons: "LAX security is awful. We never left the airport (arrived LAX from Sydney AU) yet were forced thru security again. Had to remove shoes, was scanned and "frisked" by TSA to get to Denver. To go to Australia, Denver TSA waived the removal of shoes, skipped the scan for the metal detector and no one touched me, ditto for LAX on the trip to Sydney. Where's the uniformity or standards for TSA?? Why did I have to be subjected to this garbage on the way home?? This is why I despise flying. It makes no sense to me. This ruined what was a great vacation."

Pros: "Not much. Boarding by "zone" works ok, but is no quicker than most other boarding methods."
Cons: "Boeing 767-400ER seats had no leg room for 6'+ traveller like me. The entertainment system was so old that there were no 115v outlets or USB ports. On a 7-hour flight, that is a significant problem for travellers today with multiple electronic devices. Finally, we were not told in advance that we had to go through security twice and through US Customs BEFORE leaving Dublin. So, the 6-hour layover at JFK was a complete waste of our time as we did not have to go through Customs there."

Pros: "Free drinks and snacks - great entertainment system (please read this Frontier)!"
Cons: "Boarding process was agonizingly slow and ineffective"

Pros: "I can’t make it in mexico city on tuesday, wednesday’s performance had to be cancelled and we need to pay the cancellation fee 11500 mexican pesos, please reimburse on the credit card"
Cons: "I can’t make it in mexico city on tuesday, wednesday’s performance had to be cancelled and we need to pay the cancellation fee 11500 mexican pesos of the studio and musicians"

Pros: "The staff really helped me out getting on standby so that I didn't have to wait for a 9 hour layover. Overall great experience and great staff."

Pros: "In a pinch they were able t"

Pros: "Everything was perfect !! Staff friendly"

Pros: "Great in every way"

Pros: "It got me home, eventually."
Cons: "Poor communication, a 6 hour delay followed by a 7 hour layover (during which we had to sleep on an airport floor because Delta couldn't offer us any hotel vouchers). Gate agents disappeared after 7pm becuase they were due to be done with their shifts when our flight was originally supposed to leave at 6 pm. It felt like we were trapped in the movie The Terminal. Oh! And our bag was misrouted, because that was just how things went those 2 days. All in all a 6 hour trip turned into 18 hours. I could have driven home in that amount of time!"

Cons: "Check in lines were crazy long"

Cons: "My daughter was stuck in SLC for 5 hours because there 1 cancelled flight and 1 delayed flight. It was very upsetting not knowing when she going to arrive in Denver."

Pros: "First leg from San Diego was excellent."
Cons: "Arriving in SLC discovered out flight to Denver was CANCELLED! Had to reschedule to the next day. Not fun!"

Pros: "App is good and convenient to use."
Cons: "The app went down just as we were getting ready to board and luckily i had a printed pass and it took some extra time to check in."

Pros: "really helpful and friendly service and nice seats."

Cons: "I don't like that I already completed this survey several days ago and have been receiving reminders to do so. I guess you don't have a good system in place for knowing who has and has not completed your surveys. That's too bad."

Pros: "The boarding process in Atlanta was as smooth as could be expected given that it was a full flight. I appreciated the gate announcer's suggestions to everyone about how to ease the overhead baggage crunch."
Cons: "Economy is very tight quarters."

Pros: "Crew was all very nice"
Cons: "Flying is always uncomfortable"

Pros: "When deplaning in Denver, I was impressed that the captain was the staff who got behind my wheelchair and offered to push me up the walkway :)... New aircraft, kind staff, shorty flight!"
Cons: "Nothing disappointed, butt i didn't have any good besides pretzels."

Cons: "Excellent service excellent pilot"

Pros: "Overall, the flight was very smooth and I thought the crew did a great job."
Cons: "I know this is a federal regulation, but I have to mention it as it is part of the boarding process. For the life of me, I can't understand why it is necessary to go through security again after re-entering the country. Understandable that I have to go through customs, but going through security again is ridiculous."

Pros: "Flights were both on time and boarded quickly. Crew was wonderful!"

Pros: "Entertainment"
Cons: "This is my third flight this year with Delta and every time we wait for the "crew" to get off from another flight. And as soon as they get there we can board. It's getting very annoying. Fix it."

Cons: "long wait and delayed flight"

Pros: "WiFi, good flight attendants"
Cons: "Would like to see Direct TV along with Delta Suite so can watch live TV"

Pros: "One male attendant from the first class cabin - super sweet and attentive to our needs even tho we're not seating in the premium cabin"
Cons: "Junior attendants in economy comfort seat - so lazy and whiny!"

Pros: "Very professional and caring."

Pros: "plane had individual movies for free with each seat!"

Cons: "I've only experienced delayed flights with Delta ... and this was no exception. It wasn't weather-related, nor a late flight delivering a plane - just no ground crew to service the plane between flights."

Pros: "nice snack"

Cons: "We did not board at the scheduled time, although I believe we arrived on time. The crew was demeaning and singled out individuals who were causing the aircraft to not move. It was in a very pretentious manner, not like southwest personnel who have similar antics but with a playful tone. The plane is a small one where bags don't fit overhead and many head bumps occur. We arrived fine which mean the flight was successful but it was not very enjoyable."

Pros: "Left on time, arrived early. Great cabin service, attentive and polite. Comfort Plus seats are worth the extra few bucks."
Cons: "Nothing. Low rating for entertainment only because there really wasn't any, but I wouldn't have used it anyway, so no big deal."

Pros: "Onboarding was easy and smooth. The plane was clean and the seats were comfortable. WiFi easily connected, too. Much better than expected for a budget airline."
Cons: "Nothing."

Pros: "Nothing. Delayed for 4 hours. No time change updates were ever provided at the airport. No communications provided as to why our flight was delayed. No other options given. No food or drink vouchers given & of course, no discounts provided for future travel. Not that would EVER fly Sun Country again"
Cons: "Communication and updates. At the very least, food and drink vouchers. 4 hours is a LONG time to be delayed. Extra points had the airline reimbursed their $40 ONE WAY bag fee regardless whether it’s a carry on or checked luggage."

Pros: "Everything was well executed; friendly staff, clean plane, good entertainment options"

Cons: "My seat was hard and worn out."

Cons: "It was delayed 3 hours due to rain that lasted about 30 minutes"

Pros: "Not crowded, and enough space"
Cons: "My luggage was lost"

Cons: "More room!"

Pros: "I got to change my seat"
Cons: "The flight attendants were rude. Our flight was delayed and we were not updated nor given a reason as to why."

Pros: "I liked the crew and the fact that I could reserve a seat. I also like that they use terminal A in the DEN airport and terminal 2 at MSP."
Cons: "The legroom was none existent, my seat was hard as rock, and it did not recline. Also, aisle seats have smaller under seat space than the other seats."

Pros: "No food nor entertainment, thus low ratings in those areas. You could buy snacks but I brought a granola bar to go with complimentary coffee, which was good. Hated paying extra for checked bag and seat reservations. Added $58 to fare but it was cheap."
Cons: "On time."

Pros: "The plane was actually a bit early in leaving which was nice."
Cons: "Could see baggage handlers throwing items on the conveyer belt. Always an issue to me. Like most flights these days, the seats were cramped but not as bad as others."

Pros: "Mediocrity is really the aim of an airline this tier, correct?"
Cons: "The hour delay, on top of an already 3-hour layover, in a terminal that wasn't even connected to the rest of the airport. The least you could do in a situation like this offer complimentary snacks to make up for it."

Pros: "Lots of room and I had an exit row. The staff was friendly."

Pros: "Everything ran smoothly"

Pros: "Every thing"
Cons: "Don’t know yet"

Pros: "Convenience of a non stop from Denver to Mazatlan"

Cons: "Flight Attendant skipped our row when offering drinks. No wifi, no entertainment, no snacks. Paid $25 to check one small bag."

Pros: "leg space OK"
Cons: "we were moved to a different gate for boarding. Then the flight ahead of ours had mechanical problems and we were informed of a 1 hour delay. Then we were moved back to our original gate. There were some elderly folks who were quite confused and other passengers had to help them understand the changes."

Pros: "Friendliness, clean aircrafts, leather seats, larger seats, tray tables, on time, willingness of ticketing agents to move your seat"
Cons: "No snacks (free), must pay for a seat"

Pros: "As to be expected, the cabin was crowded. The flight attendants were great and the service superb."
Cons: "There was a three hour delay, perhaps due to weather. The late plane arrived, as expected, at 1 pm, with a departure time of 1:40 pm. Including a needed ten minute de-icing procedure, we actually took-off at 2:30 pm. I never found out what caused the three hour delay."

Pros: "friendly fast and efficient!"
Cons: "Sitting in the back of the plane!"

Pros: "Friendly attendants and an on time departure. Flying terminal 2 in Minneapolis is easy and much less crowded."

Pros: "Nonstop"
Cons: "Not enough leg room, sat by rest rooms very busy at times"

Cons: "It was too cold."

Cons: "Flight was an hour late. Unprofessional staff."

Cons: "They wouldn't let me on the plane. See about"

Pros: "Boarding was good, not glitches. The crew was very accommodating with luggage having to be checked at the gate because of inadequate room in the overheads. Seating quite comfortable on the 737."
Cons: "The website is quite difficult to navigate and trying to get confirmation on an iPhone and the "tickets" seemed not user friendly. I was able to confirm 5 of 6 tickets but when I tried to finish #6 I ended up in some iPhone Safari glitch that wouldn't let me finish the confirmation even though the final step of seat selection was done. Couldn't find where the "electronic" boarding passes were stored. There seems to be no specific APP like Delta's which worked like a charm."

Pros: "Direct flight at a great price."

Pros: "Always a pleasure to fly Sun Country"

Cons: "I was one of the last ones to check in on a flight I had already purchased a ticket for in economy seats but had to pay $15 extra at check in for an economy seat. Paying extra should be if I want to upgrade a seat and not for a seat in an area that I already paid for. This was definitely not an upgraded seat. I will avoid flying Sun Country in the future."

Pros: "2nd leg of flight... Again, Everything was great, no complaints. The roomy, leather seats made the 21/2 hr flight easy. The crew was very respectful and professional. The way flying is suppose to be. Thank you. John"
Cons: "No complaints."

Pros: "I always have a good experience on Sun Country."

Cons: "small seats and when we go into the air there were plenty of seats to spread out. The crew should have announced that it would okay to disberse."

Pros: "Great service amd friendly"

Pros: "Flight went on time, the price was great, Appreciated the complimentary beverage, The crew was nice"

Pros: "Quick smooth flight with professional service, would recommend."
Cons: "It was impossible to find a dog carrier that was up to your standards. I ended up settling for something last minute. It would be nice if pet standards were more clearly identifiable."

Pros: "courteous staff"
Cons: "Delayed due to weather. Not much to do there."

Pros: "Great price Easy reservation to make Well organized at the gate and with boarding On time"
Cons: "I did not find that I had any input as to seat selection"

Pros: "Flight was better then expected."

Pros: "Friendly staff. Helpful. Accommodating."

Cons: "I arrived to the airport about 50 minutes prior to departure due to an unexpected delay. After a poor experience with the online check-in tool (it failed to allow us to check in & wouldn't let me purchase a checked bag), my girlfriend & I made it to the check-in desk about 40 minutes before departure (which has never been a problem with any other airline). The receptionists practically laughed at me when I asked to check in, and without missing a beat or even checking anything on the computer, they told me that the plane was already on the runway waiting to depart. We asked if they could help us book a make-up flight, and they practically laughed again and said, "Yeah, for next Sunday." I found this hard to believe that the plane was on the runway so early. The whole experience was very unpleasant, and we received little help from them. After a half-hour wait on the phone, I was offered a voucher for another Sun Country flight. Very dissatisfied with this. I appreciate the direct flight from MSP-SAV, as I don't think any other airline offers it. But I don't think I'll fly with Sun Country again."

Pros: "The smooth boarding and friendly flight attendants"

Pros: "would absolutely fly Sun Country again! Clean plane. on time. last minute flight was an awesome price!!"

Pros: "Easy check-in at ticketing."

Pros: "Thank you, SunCountry. This was our first time on your airline and I could not have been more impressed. The process was smooth, simple and extremely timely. Also appreciate the allowance of a carry on at no extra cost. The staff was pleasant and kind. We really enjoyed our experience."

Cons: "Didn't get to Denver via Sun Country, please see previous."

Pros: "Short and smooth"

Cons: "Because we booked through a third party , kayak, we could not pre-check in online"

Cons: "We never got off the ground because of mechanical problem. I was sent back to the terminal where I waited in line for 2.5 hours. Finally SC put me on a different airline on a flight that left 12 hours later. No compensation for food or other costs incurred as a result of this problem. I understand that things don't always go right but it is important to provide good customer service on those occasions. SC failed me."

Pros: "The aircraft was convenient"
Cons: "The flight was delayed for an hour and then the bagging claim took too much time so I missed my bus."

Pros: "Free novies"
Cons: "Food service and better social distancing"

Pros: "Everything was great"
Cons: "Nothing"

Pros: "Great price!"
Cons: "More food."

Pros: "The place to charge the phone is easily accessible on the back of the seat in front (as opposed to underneath)."
Cons: "Did not like that I had to check my bag at the gate"

Cons: "Had to clean my seat before seating."

Cons: "The legroom is not sufficient for taller people"

Pros: "Crew was tight, friendly, flight comfortable & painless."

Pros: "On time. Fast boarding. Comfortable seating."

Cons: "Unable to play entertainment on my compatible device."

Cons: "The terrible communication for delays and boarding."

Pros: "Horrible staff at LAX boarding gate. Been treated horribly by incompetent and rude AA staff."
Cons: "Hire only friendly people for this type of job. Hire people knows basic math. Train their well on how to communicate with people."

Cons: "Feeling of being cramped"

Cons: "The plane had a mechanical issue that they needed to address (due to the fact that they prior crew did not address it) and we sat in the gate for 2 hours waiting. No worries water was offered by crew and the flight had no food."

Pros: "On time flight. We were even a little early."
Cons: "Those seats are just crammed in there aren’t they?"

Pros: "The notifications regarding my connection and baggage claim."
Cons: "Nothing."

Cons: "Delayed multiple times"

Cons: "Extraordinarily rude staff, no information, mess with gates, staff not willing to help. Really rude and awful-worst experience ever!"

Pros: "No major screw-ups this time!"
Cons: "It's AA, let's not try too hard here."

Cons: "I will never, ever book with Kayak again"

Pros: "Pretty standard flight"
Cons: "Inconvenient timing and overcrowded with obnoxious children sitting on laps. No attempts made to change their behavior by crew or parents."

Pros: "Fine for a domestic flight. Normally, American Airlines offer a small snack to go with the drinks. But on this particular flight, they went the United way and offered nothing but drinks. Crew was pleasant enough during the flight, although they didn't greet half of the passengers entering or exiting the plane."
Cons: "Flight was a little late taking off and therefore getting to Denver. But there was no announcement about it. There was one announcement from the captain, but it was so soft that I couldn't hear anything. Upon landing and arriving at the gate, we stood there for a while with no lights on and seatbelt sign on, but no explanation of what was going on. There was no welcome to Denver message either. Maybe their announcement system was down."

Pros: "Not using kayak."
Cons: "Worst flights in history. It took three days to get from Italy to the US. Do not use kayak!"

Pros: "Great service in first class"
Cons: "N/A"

Pros: "Great service"

Cons: "3rd flight in two weeks suck sitting next to a morbidly obese person. They should be forced to purchase two seats."

Pros: "The crew was amazing - agreeing to work extra because it was Christmas eve and they wanted us all to get to our destinations for Christmas. They were very gracious and helpful."
Cons: "We were over an hour late to leave. I understand the reason for the delay because of weather. What I was disappointed in is that the delay was not announced until our actual scheduled time to leave. It meant people coming to pick me up didn't get the change information in a timely manner."

Pros: "Amazing entertainment selection, comfortable."

Pros: "The first leg had awesome pasta.Then, on the 2nd leg, Philly to Denver, they had a "pay for meal" option for turkey with Chutney sandwich - again, delicious. I should add that the service was very good as well."

Pros: "Almost empty in economy"
Cons: "I liked everything"

Pros: "Flight crew had a great sense of humor - they were extra friendly while boarding as well, made traveling with AA the best! Boarding was delayed due to previous flight but our pilot even managed to get us to Denver early! Wish I could have this crew everywhere I go!"

Pros: "The airplale MD 80 are old"

Pros: "it was fine. flight left on time and the crew was nice."
Cons: "that you have to pay $100+ for economy plus to get the legroom you used to get for a regular ticket."

Cons: "They were late because of bad scheduling and the gate agent was rude"

Cons: "I loved everything"

Pros: "Friendly crew. Due to the apparent regularity of excessively delayed American Airlines flights, they had the staff at O'hare bring a cart filled with cheap canned juice and Diet Soda to lessen the blow of their consistently delayed flights."
Cons: "Like every other American Airlines flight I've ever been on, it was delayed. Including the American flight from Denver to Chicago. We pay entirely too much money to these airlines for them to deliver such painfully mediocre service and consistently delayed flights. I recommend that this airline do a SERIOUS audit of their Preventative Maintenance/Service division across their hubs. If I fly American, I would bet my entire checking account that the plane will be delayed well over 2 hours."

Pros: "was a pain checking extra baggage. No one seemed to know what to do.. Apart from that AA was good."

Cons: "Indian vegetarian rice uncooked vegetables cold inedible when asked about different food no protein no vegetables Please have better food more options for vegetarian"

Pros: "Extra blanket and pillow. Empty seat to sleep in. Fairly clean interior for the most part."

Cons: "Missed that flight because my finair was delayed at Helsinki"

Cons: "Three gate changes and 45 minute delay. Same happened two years ago"

Pros: "Missed the flight. Money was not refunded."
Cons: "Nothing"

Pros: "More improved than the last trip I took with AA to Denver. Efficient boarding."

Pros: "Flight was on time through United since we had to be rescheduled from our original flight with American."

Pros: "Nothing. AA is the worst airline. Period."
Cons: "Rude flight attendants, delayed flight (as always), just AWFUL."

Cons: "Could not read paper when passenger in front reclined seat. No space between rows."

Pros: "Flight not entirely sold out. So they let my 14 month grandson have an empty seat between my daughter and I. That was a great gift since he doesn't sleep and is jumping and crawling all over the place. And I'm sure the other passengers were breathing sighs of relief!! Also super smooth landing and nice flight attendants."
Cons: "Flying with an active 14 month old toddler boy and of his "stuff" is nothing less than anxiety provoking. Not much the airline can do.."

Pros: "The departure time. This left enough time to get to the airport and go through security without rushing!"
Cons: "Sitting in the middle Paying for luggage ( I wish Southwest flew out of ORD)"

Cons: "No complaints."

Pros: "Timing and transit time was excellent"

Pros: "Everything."
Cons: "Nothing."

Pros: "Amazing Crew! Fast flight!"
Cons: "Security"

Pros: "Crew was very helpful Everything was on time"
Cons: "Very bumpy ride (not anyone's fault) Very uncomfortable seats"

Pros: "the non-stop flight works very well. lay overs are never welcomed, but tolerated because they need to be"
Cons: "hard to think of anything"

Cons: "The padding on these seats."

Pros: "Flight speed"
Cons: "The crew needs to remember that we are all watching and listening to them hoot and holler with themselves. During the flight the head attendant was watching a movie on her personal device. At this point anybody could do her job"

Cons: "Pathetic rationale for delay"

Pros: "Everything was simple and it was cool that they let the staff wear comfy clothes"
Cons: "Usb chargers in the seat, and free refreshments and peanuts"

Pros: "Left on time, arrived early, deplaned quickly because no one had bag"
Cons: "Reclinable seats"

Pros: "Crew was nice and efficient."
Cons: "Check in counter needed more help-line very long"

Pros: "Allegiant is a Budget airline. Good fares and great service. Nonstop service to less traveled destinations"
Cons: "Nothing for the price."

Pros: "Crew was nice."
Cons: "Not having so many extra charges and having to pay for a carry on"

Pros: "The boarding wasn’t smooth, there were 3 women at the podium listing zones and it was very mumbled and low, quite hard to hear despite the small area dedicated to Allegiant passengers."
Cons: "The women at the podium listing flights could have been friendlier and more customer service oriented... there was a lot of mumbling into the speaker for boarding ... and the person kept giggling into the mic. Once past boarding, everything was great !"

Pros: "Great crew. Good on-time flight (early, actually). Smooth boarding."
Cons: "Standard no-frills gripes. Seat is tolerable but basic, no recline. No power, zero inflight entertainment, etc etc. They won't even give you a sip of water for free, which is just absurd in my opinion. They did give me a free cup of ice... so I guess ice + time = free water..."

Cons: "Delayed due to weather"

Pros: "No The crew was not friendly at all"
Cons: "I honestly am angry that I was charged for things others where not.This is ridiculous"

Cons: "on time flight. Accurate info on app. Correct seat assignments"

Pros: "Crew was great"
Cons: "Earlier delay notification"

Cons: "I cancelled this flight and somehow it doesn’t show in your records and now I cant find the cancellation.. I am not in Orlando.. last time I will use Kayak."

Pros: "Quick"

Cons: "Extra charges for everything! Asked flight attendants for a cup of water as I was not feeling well and was told I could buy some water. I was also told my carry on was too big when it clearly fit in the container at the check in process."

Pros: "Timing and ease of travel"
Cons: "Nothing"

Pros: "Friendly pilot."
Cons: "My reading light kept flashing off and on. So I couldn't read my book."

Pros: "Direct flight in less than 3 hours"

Pros: "Nothing."
Cons: "The flight was delayed by hours, with no explanation given. It was coming from Florida, with no bad weather in between. It caused us to arrive at 1 am."

Pros: "Non-stop flight at a reasonable price"
Cons: "Food choices are very limited"

Pros: "Arrived on time after boarding was delayed. Great price/ you get what you pay for."
Cons: "No diaper changing station in any of the 3 bathrooms.flight attendants could have been friendlier"

Pros: "That we made it once we were in the air"
Cons: "The 3 hour delay that should have been announced but we had to get alerts on line not from the airline but Kayak"

Pros: "Friendly staff!!"
Cons: "Hour delay on flight"

Cons: "they charged me more money because i need alleges air . ap"

Pros: "Everything the service for breakfast , the interpretation for more information about when you’re in a plane what to do in case something happened and stuff"
Cons: "They didn’t have a WiFi on for the plan I couldn’t use my phone at all"

Pros: "It was easy to book. And they helped me make changes to my flight schedule without charging me"
Cons: "Everything else is charged... from the in service beverage cart, to your boarding pass. Your baggage. Everything you have to pay for. So just be prepared for that."

Cons: "The ground crew got something stuck in the snow and we can't get off the plane because of that."

Cons: "parking my car 2 weeks in Asheville Long term was $96. I should have gone to Charlotte, parked at my friend's house and paid AA the same rate for a nicer seat and cabin leg room. a la carte pricing ran my bill up even with NO checked luggage. Asheville doesn't have a shuttle service for the long-term parking."

Pros: "on time, hepful personnel"
Cons: "my gate checked luggage was lost"

Pros: "The crew, from start to finish were great. From gate to gate The plane was nice and clean. The phone app was pretty well done also."
Cons: "I know you have to make a buck but damn. Peddling food, drink all the charges and the credit card offer during the flight."

Cons: "Our engine seats at the rear of the plane were of course a little noisy at first. We got these seats on both our flights. Hoped that at least one-way we would have managed seats with a window."

Pros: "Plane was late. 2 years ago it was late and while there at the airport I heard Allgeant routine runs hours late or cancels. 3-4 hours, not an hour. Good thing I dont fly too often"

Pros: "On the way there and back the staff was friendly, the flight was smooth and and overall everything was just great. This was my first time flying with Allegiant and I will definitely do it again."

Pros: "I had 44 min they wouldn't give me my boarding pass then the flight was delayed to 5:30 and they still wouldn't allow me up."

Pros: "Flight left and arrived on time. Boarding was OK."
Cons: "Not even water provided on flight. I miss amenities."

Cons: "Flight delayed 3 hours coming in and 5 hours going back. This is unacceptable. I will never fly Allegiant Airlines again."

Pros: "I liked that they had a direct flight from Los Angeles to Bellingham."
Cons: "The delays were horrendous and a google search reveals this to be so common it makes me wonder if it's not part of their business model. Like, so bad I ended up booking a return flight on Alaska and just ate the extra $300."

Pros: "Price of flight and it was non stop to Fort Wayne, IN."
Cons: "Flight was delayed 60 mins, no explanation given. We flew in a Sun Country Plane instead of an Alliegiant plane. Sun Country had more leg room and free non alcoholic drinks. So it was worth the delay and plane change. Made it safety to Fort Wayne."

Cons: "Did not check in or take this flight. Trip up to NJ was so bad I could not fly back. Tried to contact company and was told they could not assist in anyway. So lost ticket cost. Live and Learn. Do not fly this line."

Pros: "Great service and very clean plane. Staff did everything to accommodate everyone's needs."
Cons: "There was a lot more turnulance than expected which could have made for our shaky landing but the pilot did a great job regardless."

Pros: "Well-priced. Good seat spacing and aisle size, good atmosphere. Easy to find overhead storage and boarding is quite fast and well organised."
Cons: "No complementary drinks, no TV to watch. Which is fine since those aren't necessary, but it's good to know if that's something you're willing to pay extra for."

Pros: "Allegiant is a great flying experience! A little bit of a wait at BLV,but that will be fixed once they get the other TSA checking completed. VLP was a smooth and easy experience!"
Cons: "We weren't given a menu in the Kayak App to choose seats or bags at purchase. Kayak needs to rectify this. It caused us to spend more money on our bags especially..."

Pros: "We eventually got to Las Vegas."
Cons: "Everything. Spend an it make and book with someone else."

Cons: "After arriving to the airport to check in we were told there was a 6 hr delay. Thanks for the heads up since we could've hung out more before heading to the airport."

Pros: "flight took off on time"

Pros: "Nothing"
Cons: "Flight attendants passing out drinks completely skipped us, even though we were looking right at her."

Pros: "Nothing . Flight was cancelled"
Cons: "Refund my money!"

Pros: "Stuck in Chicago. Never made it to Denver because of weather. Had to get hotel."
Cons: "Better accommodations by United."

Cons: "It sucked in many ways. But that wasn't united's fault. The weather was threatening lightning in Denver and of course because of that the world stops turning."

Pros: "Delayed. Bagage mis-rerouted."
Cons: "Be honest when bags are not routed correctly after assuring passenger twice that bags will be at the same airport they were re-routed too. Do not ask passengers for a bag delivery fee when the mistake was United's. Keep passengers informed of delayed flight and keep inconvenience to a minimum."

Cons: "It’s just crowded. The crew was great. Safe landing"

Pros: "Crew was nice and very efficient"
Cons: "Maintenance didn't have plane ready to depart on time"

Cons: "First flight of the day and there aren't enough floor assistants to address the sea of blinking red check-in kiosks. One poor soul is running around frantically trying to address all the check-in issues Pre-TSA doesn't start before our 5:15AM flight so after walking all the way down to the Pre-TSA checkpoint, we encountered a sign redirecting us back the normal tsa checkpoint which was overflowing with late check-in customers upset with the long kiosk check in delays"

Pros: "The crew was very nice. The flight was smooth and enjoyable. I was able to charge my phone and had WiFi access."
Cons: "There was no entertainment except on my phone. The food was a small bag of pretzels."

Pros: "Everyone was really nice, and there was a decent amount of leg room etc."
Cons: "I honestly can't say that I have any complaints about it. Thank you. :)"

Cons: "Placed in middle seat with no options for isle or window due to my ticket. No problem with that if the people next to me were not so big. Young woman to my left by window was tall and broad and slept but took up all elbow and shoulder space. Guy to my right was very obese, sweaty so kept wiping his neck, head, and face with a cloth. Also had terrible body odor. I spent the entire flight in a narrow middle seat, hunching my shoulders due to lack of space. Both people taking up some of what little room I had."

Cons: "We were delayed in Chicago due to weather coming home from Europe. We were not allowed to use the business class lounge even though we paid for business class tix. My family is still sitting in the airport waiting on their flight to dallas. We have been up now for over 24 hours. We should be allowed to be someplace comfortable for the price of the business class tickets. poor form on Lufthansa’s part."

Cons: "Delays"

Pros: "Fast boarding and friendly staff."

Pros: "We had no difficulties and the crew was friendly and helpful."

Pros: "I will try to avoid Ohare in the future. Long wait to take off. Had to RUN to make the connection. Again."

Pros: "Flight left the gate on time."

Pros: "It was on time."

Cons: "I want to clarify that I boough tiquests with Lufthansa not with United... and I had to travel United most of the time to Africa and Bach to the USA... united socks terrible ... bad food and old plain to cross the Atlantic... besides the service and the bad actitude of the employees... when I travel international I want only Lufthansa. So, kayak you tricked me ....horribly!"

Cons: "internet & movies intermittently worked"

Pros: "Everyone was very respectful"
Cons: "Sight delay and having to pay for internet"

Cons: "This flight was canceled because my initial flight was canceled by united and then I could not take the rebooked flight so I could not keep the seats together with the travellers I was with and then was placed in the back of the plane. When my flight was canceled initially no one informed me that my return ticket would be canceled which I specifically asked about. I hope never to fly united again. The day to day staff at ohare and on flight were good and courteous."

Cons: "The boarding process is horrible. You have to stand in lines that disrupt the other people trying to navigate through the airport."

Pros: "The boarding and check-in process was quick and seamless. The crew was attentive, friendly, and informative. Ohare airport has Garters popcorn!!!!"
Cons: "Seating was a little cramped, even for a small guy like me, and the only way to watch anything on the small screens provided on seats in front of you, is to pay. Honestly, I know that everything is about the bottom line, but you can at least provide 1 free movie or Channel and charge for optional premium material."

Pros: "The crew was polite and offered an extra six ounces of water in addition to the usual beverage service. The flight departed and arrived on time, which is a rarity when dealing with ORD."
Cons: "The cabin was near 80 degrees Fahrenheit for about 30 minutes of boarding. During the boarding process and taxiing, the DirecTV add ran theee times. The commercial was annoying and loud. Once would be enough."

Pros: "Was able to fly standby and get home earlier. Crew was nice and friendly."
Cons: "Slept most of the way, but this plane didn't have television screens, so limited entertainment options."

Pros: "Very windy decent into denver but pilots and crew were great."

Cons: "How they canceled one of my flights just as I landed at my layover for that flight when I look back at Boston they had a direct flight ready for my destination. Very poor management I was stuck in Chicago with no money or food for hours then after they start boarding for my new flight they tell me that I may not be able to get on even with ticket in hand. It was a joke and very stressful"

Pros: "The fact that priceline said there was nothing they could do."
Cons: "The fact that my pregnant wife and i were stranded in la guardia airlort and had to shovel out 800 dollars for last minute one way flights."

Pros: "Friendly crew."
Cons: "Passengers are stowing personal items/multiple bags in the overhead bins. This is an ongoing problem that needs attention. Armrest protocol should be made explicit. My in-flight entertainment control was covered by the passenger next to me the entire flight."

Pros: "United payed for the room and 20 bucks for food."
Cons: "Late. Missed the connection to Gillette and had to stay overnight."

Cons: "The flight delay and my missed / delayed luggage."

Pros: "It was Great Thank you"

Cons: "Delayed, missed connector flight to billings had to spend night in airport. Flight delayed 2hours to billings the next day. Worst flying experience ever will never fly United again!"

Pros: "Flight ahead of schedule. Friendly crew - got a full can of soda!! Good to see small snack reintroduced."
Cons: "Felt very cramped as was a full flight. No personal entertainment available, unless you paid for DirecTV."

Cons: "I missed my flight to San Diego from a connecting flight by a few minutes. Now I have to sit in the airport for over three hours waiting for my next flight.. not to mention it's my bday. Thanks United."

Cons: "Wish the seats were a bit more comfortable on frontier. And had to pay for carry ons. Will never ride frontier again."

Cons: "45 minutes late taking off"

Pros: "New, clean United planes! Happy crew! Snacks!"

Cons: "My boarding pass was not scanning which was holding up the line. A second person came over to approve me getting on the plane. That person made me check the size of my carry on bag, which had gotten bigger from some things I purchased in the airport but was just a touch too large for their sizer. She attempted to check the bag meaning I wouldn't have it until my final destination, which I was NOT ok with for two reasons. One was i had a 3 hour layover after this flight and needed work materials inside. The second was i was on a time crunch to get my ride at my final destination and was only traveling with carry on. She was very rude and insitant on it fitting inside the sizer as she stood over me with the tag to check my bag. I managed to take some things out that I moved into my backpack, which meant I had to awkwardly carry my blanket and travel pillow onto the plane. The most frustrating part was when I got on the plane, it was oversized top carryon bins, so the extra inch my bag grew would have been fine. Because of the time it took me to rearrange, i was the last one on the plane and all the bins had been filled with tiny second bags, but a few people on the plane had seen what happened and they rearranged a space for me. Also my video screen was broken and everyone else's worked. And there were two screaming babies around me the whole flight, but that is no one's fault."

Pros: "That we got a standby flight 6 hours earlier than our scheduled 12 hour layover. This plane was far better, newer and nicer than our international flight from London. UA929 was the WORST!"
Cons: "Snack chips don't qualify as food. Only water provided free. Out of all the star alliance members, United is the worst. We will try to not fly united again. Only entertainment you have to pay extra for. The international flight UA929 was the WORST. Old enough to all have the loop playing screens and mine didn't even work."

Pros: "Customer service"
Cons: "Delays. More than an hour and missing our connection in Denver which made us miss our car reservation and had to pay double for another car at the last moment"

Pros: "I liked arriving home in a timely fashion."
Cons: "The first gate agent responding flatly, "I have NO idea." to a gate change question. OR the Mother Superior flight attendants that couldn't wait to point and nag about seat backs and tray tables. I wonder if either of the women noticed they were talking to someone who wasnt't an English speaker? United needs to fly Southwest to learn the right way to do things."

Pros: "Crew was great and the boarding staff was very friendly."
Cons: "Flight was delayed"

Pros: "The flight attendants were all super kind."

Pros: "The flight is comfortable and the no hidden fees."

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

Pros: "1st time I ever watched the safety/instructional video. Great job because it is important stuff and I saw others paying attention as well!"

Cons: "When the guy in front of me reclined his seat, there was no leg room. Today, I literally have bruises on my knees....ridiculous '"

Pros: "Nothing"
Cons: "I didn't like that I missed this flight because your first one was late"

Read more about Delta
COVID-19 information

Safety measures for airlines flying from Illinois to Denver

Airlines flying from Illinois to Denver 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 Illinois to Denver

Mandatory masks

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

Social distancing seating

Middle seats unavailable to book on flights from Illinois to Denver

Pre-flight testing

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

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