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Illinois

$67+ Cheap flights from Montana to Illinois

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 10/22. Fares are subject to change and may not be available on all flights or dates of travel.
BZN — ORD
Oct 11 — Oct 181
Sat 10/11
Sat 10/18
1 adult, Economy
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Cheap flight deals from Montana to Illinois

Keep the following information in mind while searching for Montana to Illinois flight deals. Data was last updated September 11, 2025.

Round-trip from

$133
(United Airlines)

One-way from

$67
(United Airlines)

Popular in

November

Cheapest in

July

Average price

$371

Good round-trip deal

$253 or less

Good one-way deal

$196 or less
From Montana to Illinois
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One-way flight from Montana to Illinois
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Highest demand for flights based on searches. 14% potential increase in price ($67 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease ($14 potential savings vs. average RT price).
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Average for round-trip flights in September 2025
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Price to beat on a round-trip flight from Montana to Illinois.
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Price to beat on a one-way flight from Montana to Illinois.
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Find flight deals from Montana to Illinois

Cheapest flights from Montana to Illinois
Explore the most affordable flight options available from Montana to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 11, 2025.

This United Airlines deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/158:00 amBZN - ORD
Nonstop3h 05mUnited Airlines
Sat 10/184:40 pmORD - BZN
Nonstop3h 18mUnited Airlines
Deal found 9/10$133
This United Airlines deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/312:50 pmBZN - ORD
Nonstop3h 05mUnited Airlines
Sun 10/54:40 pmORD - BZN
Nonstop3h 18mUnited Airlines
Deal found 9/10$165
This United Airlines deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/1612:50 pmBZN - ORD
Nonstop3h 05mUnited Airlines
Sun 10/199:15 amORD - BZN
Nonstop3h 24mUnited Airlines
Deal found 9/11$191
This Southwest deal was found by Cheapflights users on 9/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/110:50 amBZN - ORD
1 stop11h 15mSouthwest
Sat 10/111:50 pmORD - BZN
1 stop8h 35mSouthwest
Deal found 9/8$199
This Alaska Airlines deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/303:02 pmBZN - ORD
1 stop8h 22mAlaska Airlines
Sun 11/25:00 amORD - BZN
1 stop9h 08mAlaska Airlines
Deal found 9/10$210
This United Airlines deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/1112:45 pmBZN - ORD
Nonstop2h 59mUnited Airlines
Wed 11/129:15 amORD - BZN
Nonstop3h 28mUnited Airlines
Deal found 9/11$213
This United Airlines deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/264:30 pmBZN - ORD
1 stop5h 09mUnited Airlines
Tue 9/304:40 pmORD - BZN
Nonstop3h 18mUnited Airlines
Deal found 9/11$216
This United Airlines deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/188:00 amBZN - ORD
Nonstop3h 05mUnited Airlines
Mon 10/209:15 amORD - BZN
Nonstop3h 24mUnited Airlines
Deal found 9/11$229
This American Airlines deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/2512:20 pmBIL - ORD
Nonstop2h 57mAmerican Airlines
Wed 10/299:40 amORD - BIL
Nonstop3h 10mAmerican Airlines
Deal found 9/10$229
This Southwest deal was found by Cheapflights users on 9/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/2710:35 amBZN - STL
1 stop7h 25mSouthwest
Tue 12/25:35 amSTL - BZN
1 stop5h 20mSouthwest
Deal found 9/9$239
This Hawaiian Airlines deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Hawaiian Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/73:04 pmBZN - STL
1 stop7h 59mHawaiian Airlines
Tue 10/146:33 amSTL - BZN
1 stop8h 37mHawaiian Airlines
Deal found 9/10$251
This American Airlines deal was found by Cheapflights users on 9/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/212:19 pmBIL - ORD
Nonstop2h 54mAmerican Airlines
Sun 10/58:39 pmORD - BIL
Nonstop3h 00mAmerican Airlines
Deal found 9/9$252

Cheapflights Fare Finder

 
Customize your flight search to find flights from Montana to Illinois that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated September 11, 2025.
Use the filters below to find and compare flights from Montana to Illinois that are best for you.

Fly from

Montana

Fly to

Illinois

Route

Depart

Return

Price

BozemanChicago

BZN - ORD

BZNORD

Bozeman Gallatin Field

Tue 2/24

12:30 pm-4:30 pm

Nonstop3h 00m

Chicago O'Hare Intl

Fri 2/27

9:10 am-11:33 am

Nonstop3h 23m

$149

BozemanChicago

BZN - ORD

BZNORD

Bozeman Gallatin Field

Thu 10/16

12:50 pm-4:55 pm

Nonstop3h 05m

Chicago O'Hare Intl

Sun 10/19

9:15 am-11:39 am

Nonstop3h 24m

$165

BozemanChicago

BZN - ORD

BZNORD

Bozeman Gallatin Field

Fri 10/3

12:50 pm-4:55 pm

Nonstop3h 05m

Chicago O'Hare Intl

Sun 10/5

4:40 pm-6:58 pm

Nonstop3h 18m

$165

BozemanChicago

BZN - ORD

BZNORD

Bozeman Gallatin Field

Wed 10/15

12:50 pm-4:55 pm

Nonstop3h 05m

Chicago O'Hare Intl

Sat 10/18

8:49 am-1:22 pm

1 stop5h 33m

$201

BozemanChicago

BZN - ORD

BZNORD

Bozeman Gallatin Field

Fri 9/26

4:30 pm-10:39 pm

1 stop5h 09m

Chicago O'Hare Intl

Tue 9/30

4:40 pm-6:58 pm

Nonstop3h 18m

$216

BillingsChicago

BIL - ORD

BILORD

Billings Logan Intl

Sat 10/25

12:20 pm-4:17 pm

Nonstop2h 57m

Chicago O'Hare Intl

Wed 10/29

9:40 am-11:50 am

Nonstop3h 10m

$229

BozemanChicago

BZN - MDW

BZNMDW

Bozeman Gallatin Field

Tue 2/24

11:15 am-10:40 pm

1 stop10h 25m

Chicago Midway

Fri 2/27

5:20 am-9:55 am

1 stop5h 35m

$232

BozemanChicago

BZN - ORD

BZNORD

Bozeman Gallatin Field

Thu 2/26

3:00 pm-11:44 pm

1 stop7h 44m

Chicago O'Hare Intl

Mon 3/2

7:00 pm-12:04 am

1 stop6h 04m

$237

BozemanChicago

BZN - ORD

BZNORD

Bozeman Gallatin Field

Fri 10/31

2:29 pm-11:59 pm

1 stop8h 30m

Chicago O'Hare Intl

Sun 11/2

7:37 am-2:21 pm

1 stop7h 44m

$237

BozemanSt. Louis

BZN - STL

BZNSTL

Bozeman Gallatin Field

Thu 11/27

10:35 am-7:00 pm

1 stop7h 25m

Lambert-St Louis

Tue 12/2

5:35 am-9:55 am

1 stop5h 20m

$239

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/10

Showing 1-10 of 60 results
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Best time to book a flight from Montana to Illinois

Have a flexible travel schedule? Discover the best time to fly to Illinois from Montana with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Montana to Illinois

What is the cheapest month to book a flight from Montana to Illinois?

Currently, August is the cheapest month in which you can book a flight from Montana to Illinois (average of $245). Flying from Montana to Illinois in March is currently the most expensive (average of $321). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from MT to IL?

Find hourly flight availability from Montana to Illinois. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated September 11, 2025.

When flying from Montana to Illinois, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

Weekly flight availability from Montana to Illinois

Explore weekly flight availability from Montana to Illinois. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated September 11, 2025.

The most flights from USMT to USIL are scheduled on a Monday (11 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (6 on average).

Reviews of airlines servicing Illinois

Get insights into the airlines that provide service to Illinois. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Illinois. Reviews last updated September 11, 2025.
Get a feel of what it's like to fly with Alaska Airlines, Southwest, and Delta from Montana to Illinois by reading reviews from past customers. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Comfort

7.8

Boarding

8.1

Crew

8.5

Food

7.1

Entertainment

7.0

Reviews

1 / 20
6.0
Good

Hannah,Aug 2025

SFO - SAN

Ticket said TSA pre check, but then the TSA agent said that Alaska Airlines has not actually entered the pre check information for the ticket, so I had to use regular security. During boarding, I have a disability and need to board early. The Alaska Airlines employee announced disability boarding, but then immediately announced 2 other groups to board, so I still had to fight the crowds. On the plane, the stewardess was brusk and rude. Seats were very uncomfortable, especially on lower back.
Alaska Airlines
8.0
Very good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Comfort

7.8

Boarding

8.1

Crew

8.5

Food

7.1

Entertainment

7.0

Reviews

1 / 20
6.0
Good

Hannah,Aug 2025

SFO - SAN

Ticket said TSA pre check, but then the TSA agent said that Alaska Airlines has not actually entered the pre check information for the ticket, so I had to use regular security. During boarding, I have a disability and need to board early. The Alaska Airlines employee announced disability boarding, but then immediately announced 2 other groups to board, so I still had to fight the crowds. On the plane, the stewardess was brusk and rude. Seats were very uncomfortable, especially on lower back.
Southwest
8.0
Very good
4,248 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Comfort

7.8

Boarding

8.1

Crew

8.5

Food

7.1

Entertainment

7.0

Reviews

1 / 20
6.0
Good

Hannah,Aug 2025

SFO - SAN

Ticket said TSA pre check, but then the TSA agent said that Alaska Airlines has not actually entered the pre check information for the ticket, so I had to use regular security. During boarding, I have a disability and need to board early. The Alaska Airlines employee announced disability boarding, but then immediately announced 2 other groups to board, so I still had to fight the crowds. On the plane, the stewardess was brusk and rude. Seats were very uncomfortable, especially on lower back.
Delta
8.0
Very good
7,960 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Comfort

7.8

Boarding

8.1

Crew

8.5

Food

7.1

Entertainment

7.0

Reviews

1 / 20
6.0
Good

Hannah,Aug 2025

SFO - SAN

Ticket said TSA pre check, but then the TSA agent said that Alaska Airlines has not actually entered the pre check information for the ticket, so I had to use regular security. During boarding, I have a disability and need to board early. The Alaska Airlines employee announced disability boarding, but then immediately announced 2 other groups to board, so I still had to fight the crowds. On the plane, the stewardess was brusk and rude. Seats were very uncomfortable, especially on lower back.
United Airlines
7.4
Good
8,937 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Comfort

7.8

Boarding

8.1

Crew

8.5

Food

7.1

Entertainment

7.0

Reviews

1 / 20
6.0
Good

Hannah,Aug 2025

SFO - SAN

Ticket said TSA pre check, but then the TSA agent said that Alaska Airlines has not actually entered the pre check information for the ticket, so I had to use regular security. During boarding, I have a disability and need to board early. The Alaska Airlines employee announced disability boarding, but then immediately announced 2 other groups to board, so I still had to fight the crowds. On the plane, the stewardess was brusk and rude. Seats were very uncomfortable, especially on lower back.
American Airlines
7.2
Good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Comfort

7.8

Boarding

8.1

Crew

8.5

Food

7.1

Entertainment

7.0

Reviews

1 / 20
6.0
Good

Hannah,Aug 2025

SFO - SAN

Ticket said TSA pre check, but then the TSA agent said that Alaska Airlines has not actually entered the pre check information for the ticket, so I had to use regular security. During boarding, I have a disability and need to board early. The Alaska Airlines employee announced disability boarding, but then immediately announced 2 other groups to board, so I still had to fight the crowds. On the plane, the stewardess was brusk and rude. Seats were very uncomfortable, especially on lower back.

Related info for your journey

Find useful and relevant information for your journey from Montana to Illinois. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How long is the flight from Montana to Illinois?

    Departing from Montana to Illinois will take you 2h 57m. Airlines will cover a distance of 1057 mi. Both multi-stop and nonstop flights can be found to your destination and back.

  • What are the cheapest airlines to fly from Montana to Illinois one-way?

    The cheapest airline one-way is United Airlines, with whom users have recently found tickets for as low as $67. However, be on the lookout for offers from Southwest and American Airlines, as they are both options that can get you from Montana to Illinois for a low price.

  • Can I find deals for flights from Montana to Illinois that include hotel bookings?

    Yes. In addition to deals on Montana to Illinois flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Montana to Illinois?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Montana to Illinois.

  • Can I find deals for business class flights from Montana to Illinois?

    Yes. Cheapflights offers flight deals from Montana to Illinois by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Montana to Illinois?

    Currently, August is the cheapest month in which you can book a flight from Montana to Illinois (average of $245). Flying from Montana to Illinois in March is currently the most expensive (average of $321). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

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Alternative routes for Montana to Illinois

See prices for flight routes from nearby airports that may be better suited for you.
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Top 5 airlines flying from Montana to Illinois

Discover the top 5 airlines that operate flights from Montana to Illinois. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated September 11, 2025.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$191Average$344FlexibilityNo cancel feeOn-time71%
DeltaCheapest$236Average$377FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$239Average$514FlexibilityNo cancel feeOn-time69%
Alaska AirlinesCheapest$267Average$449FlexibilityNo cancel feeOn-time75%
SouthwestCheapest$388Average$418FlexibilityNo cancel feeOn-time63%

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