What is the cheapest airline that flies from Oregon to Illinois?

Frontier, United Airlines, and Alaska Airlines are the most popular carriers operating from Oregon to Illinois

What airlines fly to Illinois?

United Airlines, American Airlines and Alaska Airlines are the top three most popular airlines that fly to Illinois from Oregon according to our data. United Airlines is the first choice among our users, with 41% of people opting to fly with this airline when traveling to Illinois. Keep in mind that there are 8 different airlines that fly to Illinois on a routine basis, so you have a few additional options to choose from.

How long is the flight from Oregon to Illinois?

The flight from Oregon to Illinois depends on which airports you’re departing and arriving from and whether or not you have a layover. If you fly from Portland (a popular airport in Oregon) to Chicago O'Hare Intl Airport (the most popular airport in Illinois), then the flight time is 3h 44m on average. If you fly from Eugene (another popular airport in Oregon) to Chicago O'Hare Intl Airport, then the average flight time is 3h 59m.

How many flights depart from Oregon to Illinois on average per day?

The number of flights available between Oregon and Illinois is 25 per day as of December 2025. The most frequent departure time is 7:00AM, with 66% of daily flights leaving at noon.

How many flights depart from Oregon to Illinois on average per week?

The number of flights available between Oregon and Illinois is 177 per week as of December 2025. The most frequent departure day is Fri, with 18% of weekly flights leaving on this day.

When did momondo last update prices for flights from Oregon to Illinois?

Prices for flights from Oregon to Illinois are updated daily.

How many operators does momondo search for flights from Oregon to Illinois?

The number of operators available for flights from Oregon to Illinois is 8 as of December 2025.

How old do you have to be to fly from Oregon to Illinois?

The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Oregon to Illinois.

What documentation or ID do you need to fly to Illinois?

The necessary travel and health documents for your Illinois trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.

$68 Cheap Flights from Oregon to Illinois in 2025/26

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Find the cheapest flights from Oregon to Illinois

Round-trip

One-way

Last minute

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Cheap round-trip flights

Enter your travel dates to find the best prices.

8:45 pm - 10:02 am

PDX

STL

35h 17m2 stops

7:43 pm - 11:15 am

STL

PDX

17h 32m1 stop

$179Frontier

Mon, Jan 5 - Sat, Jan 10

10:10 am - 9:45 pm

BOI

ORD

10h 35m1 stop

12:07 pm - 11:12 am

ORD

BOI

24h 05m1 stop

$195Multiple Airlines

Fri, Jan 23 - Sun, Jan 25

6:00 am - 3:20 pm

BOI

MDW

8h 20m1 stop

5:35 am - 1:00 pm

MDW

BOI

8h 25m1 stop

$225Southwest

Sat, Jan 10 - Sat, Jan 17

1:55 pm - 11:50 pm

BOI

ORD

8h 55m1 stop

6:06 pm - 11:59 pm

ORD

BOI

6h 53m1 stop

$228Alaska Airlines

Tue, Jan 20 - Wed, Jan 28

11:25 am - 5:13 pm

PDX

STL

3h 48mnonstop

6:20 pm - 8:30 pm

STL

PDX

4h 10mnonstop

$229Alaska Airlines

Thu, May 21 - Wed, May 27

1:24 pm - 9:15 pm

PDX

ORD

5h 51m1 stop

6:29 pm - 12:39 am

ORD

PDX

8h 10m1 stop

$232United Airlines

Sat, Jan 17 - Tue, Jan 20

1:24 pm - 9:15 pm

PDX

ORD

5h 51m1 stop

4:15 pm - 6:56 pm

ORD

PDX

4h 41mnonstop

$233United Airlines

Sat, Jan 24 - Sun, Feb 1

8:45 am - 6:30 pm

PDX

MDW

7h 45m2 stops

8:05 am - 3:05 pm

MDW

PDX

9h 00m1 stop

$233Southwest

Sat, Jan 31 - Sun, Feb 1

1:40 pm - 11:25 pm

BOI

STL

8h 45m2 stops

3:31 pm - 11:59 pm

STL

BOI

9h 28m2 stops

$236Delta

Thu, Jan 22 - Mon, Jan 26

11:35 am - 12:25 am

PDX

STL

10h 50m2 stops

7:00 am - 6:48 pm

STL

PDX

13h 48m2 stops

$236Delta

Fri, Feb 20 - Tue, Feb 24

Alaska Airlines flights from Oregon to Illinois

Our best Alaska Airlines deals on Oregon to Illinois flight tickets

Alaska Airlines

Jan 20

BOI1:55 pmBoise Air Term. Gowen Fld

8h 55m

1 stop

ORD11:50 pmChicago O'Hare Intl

Jan 28

ORD6:06 pmChicago O'Hare Intl

6h 53m

1 stop

BOI11:59 pmBoise Air Term. Gowen Fld

$228

Find similar

Alaska Airlines

May 21

PDX11:25 amPortland

3h 48m

STL5:13 pmLambert-St Louis

May 27

STL6:20 pmLambert-St Louis

4h 10m

PDX8:30 pmPortland

$229

Find similar

Alaska Airlines

Feb 4

PDX1:38 pmPortland

8h 12m

1 stop

ORD11:50 pmChicago O'Hare Intl

Feb 11

ORD3:44 pmChicago O'Hare Intl

10h 06m

1 stop

PDX11:50 pmPortland

$236

Find similar

United Airlines flights from Oregon to Illinois

Our best United Airlines deals on Oregon to Illinois flight tickets

United Airlines

Jan 17

PDX1:24 pmPortland

5h 51m

1 stop

ORD9:15 pmChicago O'Hare Intl

Jan 20

ORD6:29 pmChicago O'Hare Intl

8h 10m

1 stop

PDX12:39 amPortland

$232

Find similar

United Airlines

Jan 24

PDX1:24 pmPortland

5h 51m

1 stop

ORD9:15 pmChicago O'Hare Intl

Feb 1

ORD4:15 pmChicago O'Hare Intl

4h 41m

PDX6:56 pmPortland

$233

Find similar

United Airlines

Jan 30

PDX1:24 pmPortland

5h 51m

1 stop

ORD9:15 pmChicago O'Hare Intl

Feb 1

ORD7:50 pmChicago O'Hare Intl

4h 42m

PDX10:32 pmPortland

$243

Find similar

Fly from

Fly to

Route

Depart

Return

Price

PortlandSt. Louis

PDX - STL

PDXSTL

Portland

Mon 1/5

8:45 pm-10:02 am

2 stops35h 17m

Lambert-St Louis

Sat 1/10

7:43 pm-11:15 am

1 stop17h 32m

$179

BoiseChicago

BOI - ORD

BOIORD

Boise Air Term. Gowen Fld

Fri 1/23

10:10 am-9:45 pm

1 stop10h 35m

Chicago O'Hare Intl

Sun 1/25

12:07 pm-11:12 am

1 stop24h 05m

$195

BoiseChicago

BOI - MDW

BOIMDW

Boise Air Term. Gowen Fld

Sat 1/10

6:00 am-3:20 pm

1 stop8h 20m

Chicago Midway

Sat 1/17

5:35 am-1:00 pm

1 stop8h 25m

$225

BoiseChicago

BOI - ORD

BOIORD

Boise Air Term. Gowen Fld

Tue 1/20

1:55 pm-11:50 pm

1 stop8h 55m

Chicago O'Hare Intl

Wed 1/28

6:06 pm-11:59 pm

1 stop6h 53m

$228

PortlandSt. Louis

PDX - STL

PDXSTL

Portland

Thu 5/21

11:25 am-5:13 pm

Nonstop3h 48m

Lambert-St Louis

Wed 5/27

6:20 pm-8:30 pm

Nonstop4h 10m

$229

PortlandChicago

PDX - ORD

PDXORD

Portland

Sat 1/17

1:24 pm-9:15 pm

1 stop5h 51m

Chicago O'Hare Intl

Tue 1/20

6:29 pm-12:39 am

1 stop8h 10m

$232

PortlandChicago

PDX - ORD

PDXORD

Portland

Sat 1/24

1:24 pm-9:15 pm

1 stop5h 51m

Chicago O'Hare Intl

Sun 2/1

4:15 pm-6:56 pm

Nonstop4h 41m

$233

PortlandChicago

PDX - MDW

PDXMDW

Portland

Sat 1/31

8:45 am-6:30 pm

2 stops7h 45m

Chicago Midway

Sun 2/1

8:05 am-3:05 pm

1 stop9h 00m

$233

BoiseSt. Louis

BOI - STL

BOISTL

Boise Air Term. Gowen Fld

Thu 1/22

1:40 pm-11:25 pm

2 stops8h 45m

Lambert-St Louis

Mon 1/26

3:31 pm-11:59 pm

2 stops9h 28m

$236

PortlandSt. Louis

PDX - STL

PDXSTL

Portland

Fri 2/20

11:35 am-12:25 am

2 stops10h 50m

Lambert-St Louis

Tue 2/24

7:00 am-6:48 pm

2 stops13h 48m

$236

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How to get the cheapest flight ticket from Oregon to Illinois

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

Prices

Airlines

Other information

What is the cheapest month to fly to Illinois?

The cheapest month to fly to Illinois from Oregon is in August. Flight prices, which tend to average around $291, are often lower during this time because this is during the off-season. If you aren’t able to travel to Illinois during the month of August, then flying in January is also cheap. Prices for this month can be found on momondo for an average of $293.

What is the cheapest day to depart on your flight to Illinois?

The cheapest day to depart from Oregon to Illinois is on a Friday when prices can be found for as low as $431. Flights from Oregon to Illinois on a Sunday will generally be more expensive and average around $538. Keep in mind that these prices on both days could fluctuate depending on the season and the demand.

What is the cheapest time of day to depart on your flight to Illinois?

Our most recent data shows that the best time of day to fly to Illinois is in the afternoon. Flights from Oregon to Illinois during this time can be as low as $318. Flights in the morning are often more expensive with an average ticket price of $487.

What is the cheapest Oregon to Illinois flight route?

Fly from Portland to Chicago Midway for the best Oregon - Illinois flight prices

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

You are more likely to see cheaper flights to Illinois from Oregon when booking weeks ahead of your departure date. In general, you can expect to find flights to Illinois for around $353 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Illinois from Oregon for as low as $293 on momondo.

What cabin class options are available on Oregon to Illinois flights?

There are 4 cabin classes available to choose from on Oregon to Illinois flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Cheap Oregon to Illinois flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Oregon to Illinois

Best Price Found	$148
Fastest flight time	3h 24m
Direct flights	Every day
Airports in Illinois	98 airports

The best one-way flight to Illinois from Oregon in the past 72 hours is $148. The best round-trip flight deal from Oregon to Illinois found on momondo in the last 72 hours is $325.

The fastest flight from Oregon to Illinois takes 3h 24m

Direct flights go from Oregon to Illinois every day.

There are 98 airports in Illinois. From Oregon there are direct flights to Chicago O'Hare Intl (ORD), Chicago Midway (MDW), Lambert-St Louis (STL).

Search flight deals

When did momondo last update prices for flights from Oregon to Illinois?
Prices for flights from Oregon to Illinois are updated daily.
How many operators does momondo search for flights from Oregon to Illinois?
The number of operators available for flights from Oregon to Illinois is 8 as of December 2025.
How old do you have to be to fly from Oregon to Illinois?
The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Oregon to Illinois.
What documentation or ID do you need to fly to Illinois?
The necessary travel and health documents for your Illinois trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.
What is the most popular plane model from Oregon to Illinois?
Based on momondo bookings for this flight route, the most popular plane model on flight routes from Oregon to Illinois is Boeing 737-800 (23.14% of total bookings). The next most popular plane models are Boeing 737 MAX 9 (17.21%), Boeing 737-900 (16.13%), and Boeing 737 MAX 8 (13.93%).

Best airlines flying from Oregon to Illinois

Compare and see reviews for airlines that fly from Oregon to Illinois with momondo

Airline	Rating	Free Cancellation	Price
Frontier	PriceFrom $96	Free Cancellation	Rating 5.8 3,076 reviews	Search Frontier flights
Spirit Airlines	PriceFrom $119	Free Cancellation	Rating 6.3 8,193 reviews	Search Spirit Airlines flights
Delta	PriceFrom $123	Free Cancellation	Rating 7.9 8,013 reviews	Search Delta flights
Hawaiian Airlines	PriceFrom $125	Free Cancellation	Rating 7.8 2,822 reviews	Search Hawaiian Airlines flights
Southwest	PriceFrom $179	Free Cancellation	Rating 8.0 4,253 reviews	Search Southwest flights
American Airlines	PriceFrom $196	Free Cancellation	Rating 7.2 11,052 reviews	Search American Airlines flights
Alaska Airlines	PriceFrom $217	Free Cancellation	Rating 8.0 11,506 reviews	Search Alaska Airlines flights
United Airlines	PriceFrom $222	Free Cancellation	Rating 7.4 9,102 reviews	Search United Airlines flights

Why use momondo?

Why should I use momondo to find a flight deal from Oregon to Illinois?

momondo collates all your flight options in one place and lets you filter them to find the perfect flight from Oregon to Illinois. momondo saves you time and could save you money on your trip.

Can I find flights from Oregon to Illinois with flexible booking policies on momondo?

Flights from Oregon to Illinois with flexible booking policies can be found by using the search form above and then selecting our dedicated flexible booking filter, which will highlight only the flights where this policy is applied.

How can momondo help me find flights from Oregon to Illinois?

Once you have performed a search for Oregon to Illinois flights, momondo helps you find the right one by offering useful filters to narrow down your flight selection. Flights can be filtered by multiple factors such as airline, airport and price; but also by other criteria like aircraft type and payment method.

I’m not ready to book a flight from Oregon to Illinois right now. Can momondo alert me if prices change?

Yes momondo offers price alerts on flights to Illinois from Oregon. After performing a search on this page you should be able to see the price alert set up feature. Simply provide a valid email address and momondo will instantly alert you when prices change.

An easier way to manage your Illinois trip

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Find better results for your trip to Illinois

Popular cities in Illinois

Flights to New Yorkfrom $50

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Flights to Chicagofrom $51

Flights to Orlandofrom $50

Flights to San Franciscofrom $53

Flights to Las Vegasfrom $38

Flights to Washington, D.C.from $58

Flights to Bostonfrom $50

Flights to Atlantafrom $47

Flights to Dallasfrom $51

Flights to Seattlefrom $55

Cheap flights from Oregon to Illinois from $68

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Oregon to Illinois departing on 1/16. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

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Find the cheapest flights from Oregon to Illinois

Cheap round-trip flights

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Alaska Airlines flights from Oregon to Illinois

Our best Alaska Airlines deals on Oregon to Illinois flight tickets

United Airlines flights from Oregon to Illinois

Our best United Airlines deals on Oregon to Illinois flight tickets

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Use the filters below to find and compare flights from Oregon to Illinois that are best for you.

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How to get the cheapest flight ticket from Oregon to Illinois

What is the cheapest month to fly to Illinois?

What is the cheapest day to depart on your flight to Illinois?

What is the cheapest time of day to depart on your flight to Illinois?

Our most recent data shows that the best time of day to fly to Illinois is in the afternoon. Flights from Oregon to Illinois during this time can be as low as $318. Flights in the morning are often more expensive with an average ticket price of $487.

What is the cheapest Oregon to Illinois flight route?

Fly from Portland to Chicago Midway for the best Oregon - Illinois flight prices

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

What cabin class options are available on Oregon to Illinois flights?

There are 4 cabin classes available to choose from on Oregon to Illinois flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

What is the cheapest airline that flies from Oregon to Illinois?

Frontier, United Airlines, and Alaska Airlines are the most popular carriers operating from Oregon to Illinois

What airlines fly to Illinois?

How many flights depart from Oregon to Illinois on average per day?

The number of flights available between Oregon and Illinois is 25 per day as of December 2025. The most frequent departure time is 7:00AM, with 66% of daily flights leaving at noon.

How many flights depart from Oregon to Illinois on average per week?

The number of flights available between Oregon and Illinois is 177 per week as of December 2025. The most frequent departure day is Fri, with 18% of weekly flights leaving on this day.

How long is the flight from Oregon to Illinois?

Cheap Oregon to Illinois flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Oregon to Illinois

Best Price Found

Fastest flight time

Direct flights

Airports in Illinois

When did momondo last update prices for flights from Oregon to Illinois?

How many operators does momondo search for flights from Oregon to Illinois?

How old do you have to be to fly from Oregon to Illinois?

What documentation or ID do you need to fly to Illinois?

What is the most popular plane model from Oregon to Illinois?

Best airlines flying from Oregon to Illinois

Compare and see reviews for airlines that fly from Oregon to Illinois with momondo

Why use momondo?

Why should I use momondo to find a flight deal from Oregon to Illinois?

Can I find flights from Oregon to Illinois with flexible booking policies on momondo?

How can momondo help me find flights from Oregon to Illinois?

I’m not ready to book a flight from Oregon to Illinois right now. Can momondo alert me if prices change?

An easier way to manage your Illinois trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.

Get notified when prices go down

Daily price changes in your inbox - only with Price Alerts.

Find better results for your trip to Illinois

Popular cities in Illinois

Popular flights according to clicks in the last 7 days on momondo