$37 Find Cheap Flights from Montana to Illinois

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Low seasonJanuary
High seasonMay
Cheapest flight$37
Best time to beat the crowds with an average 2% drop in price.
Most popular time to fly and prices are also 10% lower on average.
Flight from Bozeman to Chicago O'Hare Airport

FAQs for booking flights from Montana to Illinois

  • How does KAYAK find such low prices on flights from Montana 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 Montana to Illinois.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from Montana 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 Montana 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 Montana 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 Montana 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 Montana to Illinois up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

  • Which is the cheapest airport to fly into in Illinois?

    Prices will differ depending on the departure airport, but generally, the cheapest airport to fly to in Illinois is Chicago Midway Airport (MDW), with an average flight price of $250.

  • What is the cheapest day to fly to Illinois?

    Based on KAYAK data, the cheapest day to fly to Illinois is Wednesday where round-trip tickets can be as cheap as $515. On the other hand, the most expensive day to fly is Sunday, where round-trip prices are $776 on average.

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

    The cheapest time of day to fly to Illinois is generally in the afternoon, when round-trip flights cost $528 on average. Morning departures are around 5% more expensive than evening flights, on average. The most expensive time of day to fly to Illinois is generally in the morning, which is peak travel time and where the average cost of a ticket is $607.

  • What is the cheapest flight to Illinois?

    The cheapest ticket to Illinois from Montana found in the last 72 hours was to Chicago O'Hare Intl Airport, at $239 round-trip. The most popular route is Billings (BIL) to Chicago O'Hare Intl Airport (ORD) and the cheapest round-trip airline ticket found on this route in the last 72 hours was $239.

  • What is the cheapest month to fly from Montana to Illinois?

    The cheapest month for flights from Montana to Illinois is October, when tickets cost $314 (return) on average. On the other hand, the most expensive months are September and December, when the average cost of round-trip tickets is $706 and $698 respectively.

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

    To get a below average price on the flight from Montana to Illinois, you should book around 4 weeks before departure. For the absolute cheapest price, our data suggests you should book 21 weeks before departure.

  • How long is the flight to Illinois?

    An average nonstop flight from Montana to Illinois takes 10h 17m, covering a distance of 1182 miles. The shortest route is Billings (BIL) to Chicago O'Hare Intl Airport (ORD) with an average flight time of 2h 55m.

  • What are the most popular destinations in Illinois?

    Based on KAYAK flight searches, the most popular destination is Chicago (85% of total searches to Illinois). The next most popular destinations are St. Louis (9%) and Moline (3%). Searches for flights to Peoria (2%), to Dubuque (0%) and to Evansville (0%) are also popular.

Top 5 airlines serving from Montana to Illinois

Need help choosing which airline to fly with from Montana 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
Alaska AirlinesOverall score based on 9968 reviews
8.2Boarding
7.1Food
7.9Comfort
7.1Entertainment
8.5Crew
Airline reviews

My youngest didn't have a assigned seat until we biard6the plane.

2.0 MediocreStephanie, Apr 2025SAN - SLC
Read more Alaska Airlines reviews

My youngest didn't have a assigned seat until we biard6the plane.

Booked a premium seats weeks ago and got an email the night before that id instead be seated in the cabin. Only reason I booked this overnight flight was for the better seating. All they are doing to compensate is giving a $29 coupon to use on another flight. I won’t be booking this airline again.

It was all great all around. Will travel with Alaska next trip.

I got the last seat on the plane, in the back in the corner against the window, and I paid a competitive price for my ticket several weeks before the flight.

Everything was good. However, the selections of movies and TV shows were boring and unexciting. It was disappointing.

Long delay before boarding. By the time I was informed of the delay I was already at the gate.

There was no seating at the gate, no where to charge your devices, super crowded. Boarding in group F meant all luggage space was taken when it was time for me to board. The boarding crew was short with everyone and seemed irritated. The luggage space was insufficient, the seat was too small for me (6'4") and very uncomfortable trip. I was in a middle seat between a person snoring the whole trip and a person with very strong body odor. The flight crew was terse and unfriendly, seemed irritated and impatient. Yelled a lot at people with earbuds in, understandable. Finally, we arrived 10 minutes early, only to sit on the tarmac for 20 minutes and wait for a gate. Worst flight experience I've had in years.

I made a mistake. Read what I wrote in the flight from Dulles to SEA. The negative experience was from SEA to BOI. Total garbage. Wont do it again.

Flight 351 SEA to BOI was terrible. We got to cruising altitude and I needed to use the restroom but the fasten seatbelt sign never came off. There was no turbulence and I'd felt the plane level off so I stood up to use the restroom about 15 minutes after we leveled off. The stewardess went over the intercom and said I needed to be seated because the captain hadn't turned off the fasten seatbelt sign....Which... Fair.... But not five minutes later she went and used the bathroom. Felt very unprofessional to leave a paying customer with a burning urethra for the entire flight and bark at them to sit down and still use the bathroom yourself. They never did turn off the seatbelt sign.

For longer trips, snacks are puny, boring and don’t have ANY nutritional value.

It is southwest seat was ok. Not the most comfortable seat

I’ve always loved Southwest. No issues at all. I was flying standby and the gate agent was extremely friendly and helpful. Boarding was smooth and I was able to get a window seat in the emergency exit row. Crew was fantastic! They were very professional and accommodating. We had to divert from our destination due to weather but the flight crew kept everyone at ease and informed us of all pertinent information. Excellent flight

The price of the tickets isn't matching the flight experience. No matter how long the flight is, you're only getting pretzels. The flight attendants looked unkept and over it.

Plz don't take away free bags and free seating

The seats were a bit cramped and worn, but otherwise okay.

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

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

It was a perfect flight in all aspects! Both legs!

Only one drink pass through the cabin for a 4 hour flight. Quite rough and bumpy landing.

Boarding process, crew were good. But the seats were so uncomfortable that was all I could focus on. I literally had to sit forward so that all 3 of us could fit in row. I will try to avoid Southwest in the future for any flights over 60 minutes.

Delta is my preferred airline. I've traveled with them for years. On time in most cases, good communication, easy to use app. Most planes are pretty nice. I was on a CRJ 700/900 however, which was pretty badly aged inside and needed a refresh. No infotainment, unreliable wifi, best to download before boarding or bring a book. Food choices are really just snacks on this flight, nice variety but about what you'd expect. Great staff and prompt in departure and early arrival too. Overall quite satisfied.

Crew was friendly Love the entertainment in the seat head rest.

Delta flight was on time, seats were comfortable, and crew was nice.

This had nothing to do with Delta… The flights were on time and flawless. The service was excellent. We purchased seats in (aisle/middle) comfort plus since this was a cross country flight. Unfortunately, the woman seated at the window was 300+ pounds and, as might be expected, covered up about a third of the middle seat also. there was absolutely nothing that Delta could have done about that… I just don’t know what the answer should be. If you purchase a seat, you should should be able to use the entire seat and not just the portion that someone else is not sitting/oozing in. Disappointing…there should be something that could be done….I'm just not sure what solution could be.

Delayed take-off. Very small plane so very scary with lots of bumps during the flight. Would never fly Delta on short flights in small 80 seaters plane again! Felt relieved when landed.

The worst part was I was NOT allowed in the lounge even though I was holding a first class ticket and have a premium American Express card. I have flown Business or First Class with many airlines. Delta is the ONLY one who does not extend this courtesy to anyone except people who hold the very expensive American Express card. As a result, I won’t fly Delta if I have any other choice.

A little bumpy ride . No food was being provided due the the turbulence. That was ok it was a short flight to my standards.

Simply outstanding. Their new lounge for Delta One customers is a cut above the rest.

The Dekta Rep that checked us in was great. She's very personable, pleasant, and can tell she enjoys her job.

The plane was old with small storage areas that had problems closing/latching and not enough storage for everyone, and worn, damaged seats. Service was great but feel a little unsafe on such well used planes.

Smooth flight. Boarding was chaotic. Could not hear the gate agent over the intercom. People were lined up in the wrong lines. Groups one and two were told to board through line one and group 3 through line 2. All very confusing. Once in the air, the flight was smooth. There was no entertainment option on this aircraft, even though it was a larger aircraft.

Overall poor for me I paid extra for seats with leg room and my regional flights exit row seats have less leg room then the others that's money that could have been saved and on my final flight home the flights air was not operating it was unbearably hot in the cabin I will be contacting United and filing a DOT complaint

There's just no way to sit fully upright and comfortably in these seats. There needs to be 2 more inches of room, and that's not something that only one person on the flight needs - the whole flight needs 2 more inches of room. If that means you sell 6 less seats, so be it. It's too close for anyone. Forcing people to pay for "premium" economy just to get "barely enough space to breathe" isn't really an answer to that.

The crew were very nice. The Chocolate is good and v there’s no entertainment. Thanks

The crew were very nice. I would have appreciated a pillow for comfort. I had a special meal that was sloppy, but the salad was great. Thanks

The plane was in Moline all night. Consequently, we assumed an on time departure at 8:15am. Unfortunately, and as is the normal case with United in Moline, we departed 2.5 hours late. When the crew came, it was discovered that there was very little heat in the plane. Seems this should have been checked hours before the crew arrived. Then when we boarded and the plane was to be de-iced, the United de-icing truck was not working! We awaited the American Airlines truck. All of this caused us to miss our connection in Chicago. My suggestion is never take United Airlines flight from Moline. We have been disappointed 80% of the time and have vowed to not take United again from Moline.

Flight was delayed two hours. No snacks and no tv screens. My bag got stuck in Chicago

The aircrew was solid, the flight was chill, I had no issues. The gate agent was not the best. I was trying to use a military bag upgrade to move my bag from under the seat to the overhead bins and he told me there’s no overhead bins on the plane, argued with me why booking put a military member in basic economy (I don’t really understand this) and made it an issue to even try to help me stating I’d have to call reservations to get a bag upgrade. When every other agent with United can add it at the gate, this man couldn’t be bothered.

They canceled our flight and left us stranded to figure it out

Everything was very good. Was able to change a make run flight leaving on direct earlier in the app -seamless!!! Well done

To start, I’d like to say that every American Airline personnel I interacted with on the ground, especially flight crew, was very friendly and did their best to help me out. Despite this, however, my experience with the airline was an entire mess. The 7:19 PM flight was heavily delayed due to weather, and pushed to 10:30 AM the next morning. Because of this, I had to spend the night inside of the airport. At some point later in the night, I got an email saying that the flight had been canceled. I called the support number, and the representative on the other line told me that the flight was still on and that I didn’t need to rebook. The next morning, no one came to the gate to open the door for the crew until almost 11 AM. By this time the flight crew had been waiting for over an hour, and they had called management to get someone to open the door for them multiple times. Around 11:30, the gate screen had changed to a different flight. I ended up buying a last minute ticket with Southwest airline just to get to Chicago, because the next flight with American wasn’t until 7:19 pm that day. Now, earlier that morning my suitcase had been sent ahead of me to ORD. I went to baggage claim to ask them if I could have my suitcase forwarded to where I was staying. The representative at SDF baggage claim said they could and put the claim in for me. As I was going back through TSA, I got an email that the airline had found my suitcase, but the next step was to send it BACK to SDF. I called the airline support number again, and I made it clear that my suitcase needed to stay in Chicago and to not come back to SDF. The representative told me that they would hold my suitcase at ORD and that it wasn’t going to be forwarded anywhere. Once I got there, I found that they had loaded my suitcase onto a plane to send it back to SDF. Thankfully, I had gotten to the baggage claim counter in time for them to put in a request to bring my suitcase back up. My refund with the airline is processing already, but because of this entire experience and miscommunication at every turn of the way, I will not book with American Airlines in the future.

The plane was late and then sat on the runway for almost 45 minutes before taking off.

Crew professional. Easy bag drop off. On time. Good entertainment.

Everything was great. Boarding, early departure, early arrival, and deplaning were smooth. Smooth flight.

Per usual, flight status, staff courtesy and professionalism were excellent

Everything was on time, we arrived early, everything worked well.

The only thing is if Wi-Fi is available after you land and taxi to the gate. It takes forever to get to the gate, and having the Wi-Fi continue would be great to bide the time at least 5 minutes before you arrive at the entrance. That is my only comment; otherwise, everything was good.

Had to wait on pilot and crew to depart and had to wait to arrive at the gate because they only had 2 crews working. Delays, delays....Planes just keep getting smaller and tighter and they nickle and dime for everything. When will an airline actually wake up and make flying more enjoyable?

Seating was horrible. Small seats. Access to flight information and extras very iser unfriendly. Kept losing internet after paying for it. Staff in madison was as unprofessional and unhelpful.

Delayed due to no crew. On a major holiday travel day.

Book cheap flights from Montana to Illinois

Recent round-trip flight deals

9/18Thu
1 stopAlaska Airlines
7h 51mBZN-ORD
9/23Tue
1 stopAlaska Airlines
8h 54mORD-BZN
$197
8/16Sat
nonstopAmerican Airlines
2h 51mBIL-ORD
8/20Wed
nonstopAmerican Airlines
3h 13mORD-BIL
$209
6/5Thu
1 stopUnited Airlines
5h 20mBZN-ORD
6/9Mon
nonstopUnited Airlines
3h 24mORD-BZN
$221
6/13Fri
1 stopUnited Airlines
7h 18mMSO-ORD
6/15Sun
nonstopUnited Airlines
3h 48mORD-MSO
$230
8/16Sat
1 stopDelta
7h 34mBIL-ORD
8/20Wed
2 stopsDelta
9h 51mORD-BIL
$234
6/5Thu
1 stopDelta
6h 05mBZN-MDW
6/9Mon
1 stopDelta
5h 35mMDW-BZN
$237
6/6Fri
1 stopHawaiian Airlines
9h 07mBZN-ORD
6/8Sun
1 stopHawaiian Airlines
10h 05mORD-BZN
$240
5/27Tue
1 stopHawaiian Airlines
7h 42mMSO-ORD
6/3Tue
1 stopHawaiian Airlines
7h 13mORD-MSO
$254
9/18Thu
1 stopSouthwest
8h 00mBZN-MDW
9/23Tue
1 stopSouthwest
6h 00mMDW-BZN
$257
6/5Thu
nonstopSouthwest
2h 55mBZN-MDW
6/9Mon
1 stopSouthwest
5h 45mMDW-BZN
$260

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Recent one-way flight deals

6/15Sun
1 stopAlaska Airlines
7h 59mBZN-ORD
$37
9/3Wed
1 stopHawaiian Airlines
7h 51mBZN-ORD
$98
9/16Tue
nonstopAmerican Airlines
3h 13mBZN-ORD
$99
6/30Mon
nonstopAmerican Airlines
3h 13mBZN-ORD
$106
6/5Thu
nonstopSouthwest
2h 55mBZN-MDW
$106
9/4Thu
1 stopUnited Airlines
6h 55mBZN-ORD
$109
9/3Wed
1 stopSouthwest
7h 55mBZN-MDW
$109
6/5Thu
1 stopUnited Airlines
5h 20mBZN-ORD
$116
6/15Sun
1 stopDelta
6h 06mBZN-MDW
$119
6/28Sat
1 stopDelta
5h 46mBZN-ORD
$119

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Last minute flights from Montana to Illinois

Last minute flight, train and bus deals

5/5Mon
multi-stopSouthwest
7h 05mBZN-ORD
5/7Wed
multi-stopSouthwest
7h 15mORD-BZN
$514
5/5Mon
multi-stopSouthwest
10h 50mBZN-ORD
5/7Wed
multi-stopSouthwest
7h 15mORD-BZN
$519
5/2Fri
multi-stopDelta
4h 08mBIL-ORD
5/4Sun
multi-stopDelta
6h 13mORD-BIL
$529
5/2Fri
multi-stopDelta
6h 28mBIL-ORD
5/4Sun
multi-stopDelta
7h 07mORD-BIL
$534
5/2Fri
multi-stopDelta
9h 48mBIL-ORD
5/4Sun
multi-stopDelta
7h 07mORD-BIL
$539
5/5Mon
nonstopUnited Airlines
3h 07mBZN-ORD
5/7Wed
multi-stopUnited Airlines
6h 44mORD-BZN
$558
5/5Mon
multi-stopDelta
9h 16mBZN-ORD
5/7Wed
multi-stopDelta
10h 46mORD-BZN
$634
5/2Fri
multi-stopAmerican Airlines
7h 37mBZN-STL
5/4Sun
multi-stopAmerican Airlines
8h 41mSTL-BZN
$651
5/2Fri
multi-stopUnited Airlines
7h 40mBZN-STL
5/4Sun
multi-stopUnited Airlines
7h 26mSTL-BZN
$656
5/2Fri
multi-stopAlaska Airlines
13h 18mBIL-ORD
5/5Mon
multi-stopAlaska Airlines
22h 11mORD-BIL
$1,234

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Everything you need to know for your flight to Illinois

Cabin class types available on flights to Montana

Cabin classes available on flights to Montana. Prices are the lowest found on KAYAK over the last 7 days. Price and availability is not guaranteed.

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