$44 Find Cheap Flights from Denver to Illinois - Compare and Save

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Cheap Flights from Denver to Illinois

Cheapest round-trip prices found by our users on KAYAK in the last 5 days
Chicago
Chicagononstop$121
Moline
Molinenonstop$309
Peoria
Peorianonstop$119
Bloomington
Bloomington1 stop$319
Champaign
Champaign1 stop$372
Springfield
Springfield1 stop$457
Decatur
Decatur1 stop$394
Chicago
Chicagononstop$121
Moline
Molinenonstop$309
Peoria
Peorianonstop$119
Bloomington
Bloomington1 stop$319
Champaign
Champaign1 stop$372
Springfield
Springfield1 stop$457
Decatur
Decatur1 stop$394
Booking Insights

KAYAK's insights & trends for Denver to Illinois flights

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

How much is a round-trip flight from Denver to Illinois?

Flight prices are below average for this route right now.

Flights to Illinois from Denver usually cost between $210 and $354 in November.
The lowest price found in the past 5 days was $121 on Frontier (Nov 13-Nov 16).

What is the cheapest Denver to Illinois flight route?

The cheapest ticket to Illinois from Denver found in the last 5 days was to Peoria, at $101 round-trip. The most popular route is from Denver (DEN) to Chicago O'Hare Intl Airport (ORD), and the cheapest round-trip airline ticket found on this route in the last 5 days was $157.

What is the cheapest time of day to fly to Illinois?

The cheapest time of day to fly to Illinois is generally at night, when round-trip flights cost $261 on average. Morning departures are around 10% more expensive than evening flights, on average. The most expensive time of day to fly to Illinois is generally in the afternoon, which is peak travel time and where the average cost of a ticket is $553.

Can I save money by flying with a layover from Denver to Illinois?

Yes, flying with a layover may cost you more time, but you can also save money on the route, with a 2 stops layover the cheapest option at $275 on average.

What is the cheapest month to fly from Denver to Illinois?

The cheapest month for flights from Denver to Illinois is January, when tickets cost $237 (return) on average. On the other hand, the most expensive months are July and June, when the average cost of round-trip tickets is $345 and $335 respectively.

What’s the cheapest day of the week to fly from Denver to Illinois?

If you are looking for a flight deal from Denver to Illinois, look for departures on Fridays and avoid leaving on a Sunday, as it's usually the priciest day. When flying back from Illinois, Wednesday is the cheapest day to fly and Monday is the most expensive.

How far in advance should I book a flight from Denver to Illinois?

To get a below average price on the flight from Denver to Illinois, you should book around 4 weeks before departure, which saves you about 44% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 10 weeks before departure.

Good to know

Low season

February

Cheapest flight

$44
Best time to beat the crowds with an average 9% drop in price.
Most popular time to fly and prices are also 9% lower on average.
Flight from Denver to St. Louis

Flights from Denver to Illinois: the best tips from KAYAK users

Insights shared by verified travelers who flew the route from Denver to Illinois 
JoanneFlew with United Airlines-Jun 2026
The runway to gate took a bit of time. So if you have a short layover pay for a seat up front .
AdamFlew with Southwest-Oct 2024
Arriving T5 at ORD on Southwest is often a LONG walk, with no moving walkways going out, to baggage claim / pickup.
BrianFlew with United Airlines-Jan 2024
Big airport. Make sure you have enough time between flights for rest, eating, etc…

FAQs - booking Illinois flights

  • How does KAYAK find such low prices on flights from Denver to Illinois?

    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 Denver to Illinois.

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

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

    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 from Denver to Illinois with an airline and back with another airline.

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

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

Top tips for finding cheap flights to Illinois

  • Looking for a cheap flight? 25% of our users found tickets from Denver to the following destinations at these prices or less: Chicago $178 one-way - $281 round-trip

Reviews of the top 5 airlines serving from Denver to Illinois

 
Need help choosing which airline to fly with from Denver to Illinois? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
8.0
SouthwestOverall score based on 4188 reviews
8.0Comfort
8.1Boarding
7.0Food
8.6Crew
7.5Entertainment
Airline reviews

Southwest has inacted unfriendly customer policies like other airlines. Watch the fine print very carefully if you are having to alter flight arrangements. Rules are now complicated and very stilted to travelers sacrificing travel funds (unlike before where the simple, straight forward flight change policy was worth the extra premium for ticket price.) On the positive side, SW Flight crews are still wonderfully helpful.

8.0 ExcellentTamara, Aug 2026
Read more Southwest reviews

Southwest has inacted unfriendly customer policies like other airlines. Watch the fine print very carefully if you are having to alter flight arrangements. Rules are now complicated and very stilted to travelers sacrificing travel funds (unlike before where the simple, straight forward flight change policy was worth the extra premium for ticket price.) On the positive side, SW Flight crews are still wonderfully helpful.

Poor customer service, no accommodation for passengers when the flight was delayed over 5 hours.

The flight was late. The crew was rude. There was no food. Cramped and uncomfortable. Nothing about this flight was good.

It was great. The gate staff were very helpful in Portland when my son forgot his rolling bag and had to go back to get it just in time to make it on the plane. We really appreciate that. Great job!

This leg was much better, but we did have to have a 3 hour lay o er after coming from a very exhausting hiccup with our flight from BNA to Den

My flight from Denver to Minneapolis was excellent. My flight from Minneapolis to Denver was one of the worst I flights I have ever experienced. I had a window seat, the gentleman in the middle seat was morbidly obese and SW should have made him purchase two seats. His elbow dug into my arm most of the way even after I asked to please be careful. I was literally squashed between the him and the window with no wiggle room. The plane was full so it was not possible to ask for a different seat. I realize I should have complained to the flight attendant but I didn't feel anything could be done to rectify the situation. I fly SW often, I will continue to do so as this was my first negative experience.

Everything went smoothly and we even arrived a little bit early.

Connecting flight is on time and boarding was a breeze!

WiFi did not work. For as outrageous as these flights cost, when they’re advertised with certain services/ features they should be in working order

I would have liked to arrive on time - not 5 hours late!

It was fine for the most part. But the volume on the announcements was way too loud, and the cabin temperature was chilly. We had the hardest landing I've ever experienced- I think it hurt my back, and the tires squealed when we touched down.

Not a United thing, but late afternoon departures from Denver with thunderstorms is always prone to delays.

Really delayed, no effort to support customers other than “sometimes we run late.”

Very easy ! Use the kiosk and bag drop and right to security within 10 min

O’hsre taxi and deboarding took 40 minutes. Needed 20 minutes extra time between connecting flights to avoid running through terminal.

Every staff member was professional, friendly and courteous. The pizza twist was ok. It was warm but too much dough.

See previous note about the passenger in Denver who threw my husband's bag out of the overhead bin in order to maker room for his own. And the flight attendant back up the new passenger.

Flight was delayed by over an hour and gate checked bags took 15 minutes to be delivered to the jet bridge.

We have taken this flight before and it is a tight connection and they were late out of denver and did not wait for us. The plane was there and the departure time had not passed but would not let us on. Next flight is very late and a connection through Newark - a big mess. Sooooo appreciate them holding the plane so we could catch the connection.

Upgrade planes to have larger overhead bins, especially on this popular route and first class. Easy flight to Chicago, good service in first class. Can't wait for seatback entertainment to be brought back. I like the free wifi and messaging with T-Mobile. Although, the tray tables are not big enough to work even on a small laptop - so why is it called "business" class?

The flights to and from Cincinnati were great at being on time for both, departures and arrivals. The planes could use some updating.

It was a dismal experience. The flight was delayed for 4 hours, and we spent hours in the plane, without air, during the summer. We were not provided with water, and the medical assistance was inadequate when it arose.

The landing the pilot was very smooth. The flight attendant was kind of rude.The boarding the plane in punta Gorda was not great made us wait out in the heat 😞

My exit seat was very comfortable Coffee was to be purchased but sodas free 😏

It was poor a four hour delay and no explanation for the delay. What’s a 35 dollars going to do. It also made me miss my car rental,

It was on time. Flight was comfortable. Staff was nice. It was the way a flight should always be.

It was cold on the flight. The crew was very pleasant. I didn't order any food. We were delayed due to Captain waiting on maintenance log. He kept us informed though. The flight itself was smooth. I would definitely fly with Allegiant again!

My 90 year old father flew with me. He needed wheel chair assistance and is nearly deaf. The staff was amazing with him.

The flight was delayed 6 hours and we were only offered an $8 food credit. My husband stood in line to get the credit for 45 minutes and when he got close to the end of the line the computers went down.

Be just a little friendlier, instead of just doing their job and speaking because it’s their job. At least act they want to speak.

The flight attendants were extremely sourly and borderline rude. I did not feel appreciated as an AA customer once.

As we approached Denver, we encountered quite a bit of turbulence. I know this can sometimes be the case as I frequently fly this route but not on American. My gripe: Usually a pilot or co-pilot alerts passengers to the possibility of turbulance ahead of time. This did not occur nor did he communiucate during what was a pretty rough ride.

Terrible. Our luggage was delayed and couldn’t be delivered for several days. We got bad information from the airline agents at baggage claim. We had to pick up our car so we wouldn’t be charged for an extra day. We got lost in the maze of airport parking. The baggage claim agents didn’t offer us any compensation for our extra time and expense. We are tired, hungry and very frustrated.

Mechanical delay and no compensation. Missed connection as a result of their delay. Mediocre performance and service. Horrible airline currently with horrible culture.

Any sort of gluten free snack option would be nice

Crew was late. Baggage was late. 2hs inside the plane waiting fro de-icing and traffic. A 3:30hs flight ended up being almost 6hs inside the airplane.

Timely boarding process, made up for lost time even after a lengthy wait for de-icing

It would have been better if I could have had my flight on time. It was delayed for 5 hours. Caused me to not be able to fulfill my promise to my granddaughters. Other than that it was a good trip.

11h50m total delay. Had to switch to another flight that was still a 7h30m delay.

Deicing in Denver took forever and I almost missed my connection. De-ice faster! Not Americans fault.

I paid for the upgraded bundle. Was worth it! Great experience round trip!

It was awful everything about it terrible I will never ever ever ride it again

Crew was kind of grumpy and there was no beverage service at all. Sodas were $4. Disappointing.

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

There's no seats that lean back with little leg space i wad uncomfortable the entire flight. Your charges for extra baggage is despicable and costly!!

There was no food and no entertainment, so I'm not sure why these are even in the survey, as my understanding is frontier does not ever offer food without a few, not even a snack, and there are no screens so unless the flight safety talk is our entertainment why ask how we liked it?. One of the flight attendants say in the back of the plane as people filed in to their seats, yelling orders about where to put baggage and telling people to hurry up. It was the least professional experience I've ever had on a flight.

Not clean and was told I would get a great seat and it was not great at all

Delayed. Text notifications were slow. Not much information o what was happening. Boarding was slow and confusing. Wasn’t even offered water other flight. Had to ask. No entertainment at all. Felt like.a Greyhound bus.

Frontier is the Walmart of airlines. Frontier has removed adjustability and comfort from their seats to make the flight lighter and save gas. This makes it impossible to sleep on their flights. Their customer service is abysmal. Once, I bought a drink on the plane, and they swiped my credit card on the plane to pay for it. Then I got three weeks of daily notices from my bank telling me they tried to charge the wrong card number over and over again. I tried to call them, but they removed the ability to actually talk to someone that can resolve such a problem from their company to cut corners. The only way to talk to someone in person is to go to the check-in counter at the airport (40 minutes drive from my house). Eventually their system gave up on trying to charge the card, after 21 days of repeated tries. They don't pad their prices even a little to handle customer service issues like missed flights. They also have a blanket policy preventing helping you reschedule a missed flight if their system says you "cancelled" your own flight online. This is a major problem because their website is broken on mobile devices, the only web browser you have at the airport when their gate staff tell you that you have to reschedule your own missed flight online because they can't help you. I tried to reschedule my flight on my android device and instead, their website crashed and "cancelled" my missed flight. When I got to the counter, the agent argued with me for 5 minutes insisting that I intentionally cancelled my own flight (implying I had to buy another flight). She missed the point: the problem was that I could not buy another flight because their website is broken. I left to avoid more conflict with the "customer service" agent. I tried to redress my issue with their only other "customer service" chanel available: the contact form on their website. The response I got was more of the same: you cancelled your own flight, according to our website / computer records, therefore we won't help you. I was trying to explain the problem with their broken website that cost me hundreds of dollars by crashing / malfunctioning and resulting in a cancelled flight, but they only had deaf ears for this problem. Worst customer service I have ever experienced. I will never buy another Frontier flight again, because it is a risky, painful move that I will likely regret often.

What I expected, nickeled and dined and a frontier flight attendant loudly complained about her job and lack of communication as she headed to the gate on her cell phone. Not professional.

More options for your flight from Denver to Illinois

Complete your trip to Illinois with a hotel stay or car rental