$96 Find Cheap Flights from Portland to Illinois - Compare and Save

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Portland to Illinois departing on 9/5. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
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Cheap Flights from Portland to Illinois

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours
Chicago
Chicago1 stop$327
Moline
Moline1 stop$349
Peoria
Peoria1 stop$331
Bloomington
Bloomington1 stop$349
Champaign
Champaign1 stop$338
Springfield
Springfield1 stop$525
St. Louis
St. Louis1 stop$201
Paducah
Paducah2 stops$442
Chicago
Chicago1 stop$327
Moline
Moline1 stop$349
Peoria
Peoria1 stop$331
Bloomington
Bloomington1 stop$349
Champaign
Champaign1 stop$338
Springfield
Springfield1 stop$525
St. Louis
St. Louis1 stop$201
Paducah
Paducah2 stops$442

Book Cheap Portland to Illinois Plane Tickets

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Portland to Illinois that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Portland to Illinois

Sat, Aug 22 - Sat, Aug 29
Southwest Logo
9:00 am - 6:25 pm
PDX
-
STL
7h 25m
1 stop
Southwest Logo
8:30 am - 10:40 am
STL
-
PDX
4h 10mnonstop
$201Southwest
Mon, Aug 10 - Tue, Aug 18
Delta Logo
12:35 am - 10:23 am
PDX
-
STL
7h 48m
1 stop
Delta Logo
7:45 pm - 11:39 pm
STL
-
PDX
5h 54m
1 stop
$211Delta
Thu, Oct 1 - Mon, Oct 5
Frontier Logo
9:34 pm - 11:51 am
PDX
-
STL
12h 17m
1 stop
Frontier Logo
12:46 pm - 8:39 pm
STL
-
PDX
9h 53m
1 stop
$240Frontier
Tue, Aug 4 - Wed, Aug 5
United Airlines Logo
8:35 am - 6:17 pm
PDX
-
STL
7h 42m
1 stop
United Airlines Logo
7:23 pm - 12:50 am
STL
-
PDX
7h 27m
1 stop
$245United Airlines
Mon, Oct 5 - Thu, Oct 8
Frontier Logo
9:34 pm - 11:51 am
PDX
-
STL
12h 17m
1 stop
Frontier Logo
5:19 pm - 8:39 pm
STL
-
PDX
29h 20m
1 stop
$249Frontier
Fri, Jul 31 - Wed, Aug 5
Multiple Airlines Logo
5:49 pm - 5:37 am
PDX
-
ORD
9h 48m
1 stop
Multiple Airlines Logo
7:20 am - 9:45 am
ORD
-
PDX
4h 25mnonstop
$329Multiple Airlines
Fri, Aug 7 - Sun, Aug 9
Multiple Airlines Logo
5:49 pm - 5:37 am
PDX
-
ORD
9h 48m
1 stop
Multiple Airlines Logo
7:20 am - 9:45 am
ORD
-
PDX
4h 25mnonstop
$330Multiple Airlines
Wed, Oct 21 - Tue, Oct 27
American Airlines Logo
6:00 am - 4:59 pm
PDX
-
PIA
8h 59m
1 stop
American Airlines Logo
12:23 pm - 7:29 pm
PIA
-
PDX
9h 06m
1 stop
$331American Airlines
Thu, Jul 30 - Wed, Aug 5
American Airlines Logo
1:45 pm - 7:50 pm
PDX
-
ORD
4h 05mnonstop
American Airlines Logo
9:30 pm - 11:59 pm
ORD
-
PDX
4h 29mnonstop
$331American Airlines
Fri, Jul 31 - Fri, Aug 7
United Airlines Logo
11:40 pm - 8:40 am
PDX
-
MLI
7h 00m
1 stop
United Airlines Logo
3:47 pm - 11:13 pm
MLI
-
PDX
9h 26m
2 stops
$368United Airlines
Booking Insights

KAYAK's insights & trends for Portland to Illinois flights

Get data-powered insights and trends into flights from Portland 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 Portland to Illinois?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from Portland to Illinois departing in August.

What is the cheapest Portland to Illinois flight route?

Data is based on round-trip flight searches on KAYAK over the past month.

The cheapest ticket to Illinois from Portland found in the last 5 days was to Chicago, at $277 round-trip. The most popular route is from Portland (PDX) to Chicago O'Hare Intl Airport (ORD), and the cheapest round-trip airline ticket found on this route in the last 5 days was $323.

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

The average price for all round-trip flights from Portland to Illinois depending on the time of departure, clicked by users on KAYAK in the last 2 weeks.

The cheapest time of day to fly to Illinois is generally in the evening, when round-trip flights cost $369 on average. Morning departures are around 29% 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 $476.

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

The average round-trip price for all non-stop flights, flights with one layover, and flights with two layovers for the route found by users searching on KAYAK in the last 2 weeks.

No, with an average price for the route of $396, prices are generally cheapest when you fly direct.

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Portland to Illinois, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Portland to Illinois is November, when tickets cost $103 (return) on average. On the other hand, the most expensive months are October and September, when the average cost of round-trip tickets is $743 and $715 respectively.

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

The average price of all round-trip flights from Portland to Illinois clicked on KAYAK for each day over the last 12 months.

Your flight ticket price will generally be cheaper if you fly to Illinois on a Wednesday and more expensive on a Monday. On your return trip to Portland, you should consider flying back on a Tuesday, and avoid Mondays for better deals.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Portland to Illinois, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from Portland to Illinois, you should book around 4 weeks before departure, which saves you about 50% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 18 weeks before departure.

Good to know

Low seasonJanuary
Cheapest flight$96
Best time to beat the crowds with an average 20% drop in price.
Most popular time to fly and prices are also 1% lower on average.
Flight from Portland to St. Louis

FAQs - booking Illinois flights

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

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from Portland 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 Portland 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 Portland 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 Portland 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 Portland 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 Portland to the following destinations at these prices or less: Chicago $224 one-way - $403 round-trip

Reviews of the top 5 airlines serving from Portland to Illinois

 
See real verified KAYAK customer reviews for airlines flying from Portland to Illinois. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Portland 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.
7.9
Alaska AirlinesOverall score based on 12631 reviews
7.0Entertainment
7.8Comfort
8.1Boarding
8.5Crew
7.0Food
Airline reviews

Alaska has clean planes, modern interiors, and good service. Major drawback is the lack of IFE seat back screens. Otherwise it could really give Delta a run for its money.

8.0 ExcellentAnthony, Jul 2026
PDX - BOS
Read more Alaska Airlines reviews

Alaska has clean planes, modern interiors, and good service. Major drawback is the lack of IFE seat back screens. Otherwise it could really give Delta a run for its money.

Left one of our suitcases behind. SUPER ANNOYING since I’m traveling solo with a lap infant 😡

The flight was direct, anytime a flight is on time, and there's not a layover that risk yet another delay is a win!!

Staff on the flight were terse, bossy, and impatient with people on the plane.

The crew was excellent. We brought our own snacks due to dietary requirements and personal preference. There was an ample beverage selection. The seating was comfortable enough. My only complaint was that there was no announcement, or at least none that we could hear, that our connecting flight was departing from a different terminal. That could been announced by the air crew in flight or before disembarking.

I was able to upgrade easily on the way home to first class. No problems with luggage. Efficient time management getting us to our destination on time

The airline was great. What was annoying as hell were the inaccurate emails from KAYAK telling me the boarding gate changed and the date of my flight was 1 day later then the actual flight 😡

The airline itself was extremely comfortable and the staff were wonderful. The communication was excellent amongst the pilots and flight attendants and the passengers. I was throughly impressed by the cleaning crew that came on the plane immediately to ready it for the next flight. I have flown a bunch of times post Covid pandemic and have never seen this! I gave the “okay” rating for the food and entertainment because I didn’t order food and there wasn’t entertainment offered through the plane (only your personal devices).

Quick easy boarding. Airport was unprepared for early landing and we were waiting in the plane for 20 minutes before getting a gate.

No complaints. One of the flight attendants was especially engaging and helpful. She was like a merging of nurse and teacher energy in one person.. The seats were very comfortable, and so nice to have extra legroom in the main cabin. Puts United and American to shame. Thanks

Flight was delayed over 3 hours. Planes were dirty. Staff indifferent. And they serve vegan pretzels as snacks.

The flight was smooth. The Southwest experience has degraded overall, but this one was okay.

No gluten free snacks. Seats felt worn or bare bones even though it was a new 737 MAX 8.

The checking experience in Orlando was terrible, almost missed the flight. Too many travelers and Southwest completely understaffed.

no service at all due to turbulence. they should've at least given us snacks, there were only 10 people on the entire flight.

For the first time in a long time, the Wi-Fi actually worked the entire flight! The flight crew was amazing as usual.

The Southwest employees (all two of them) were very nice and cheerful despite the fact the line to self-check a bag (simply drop it off) was hundreds of people long. Thank God I arrived early to the airport because I stood in this line for at least an hour. Once on the flight that had been delayed by an hour, we had no Wi-Fi and thus no entertainment. Finally, I hope the investor strong arm tactics against Southwest pay off in a short-term windfall to your C-Suite because the rest of you are screwed. I have been a faithful Southwest customer for 15 years due to everything you just got rid of. I'm flying to Idaho and Washington in October, both places I used to simply book with Southwest without a second thought now with Frontier (Washington) and United (Idaho) because they offer everything the "new" Southwest does but cheaper and at better times, destinations, etc. This really makes me sad...

It was really nice! I appreciate the gate attendant allowing families with small children to board early on in the process… that was very helpful! The internet service didn’t work with the app I was trying to use even though I paid the $8… other than that it was great! Oh and I should’ve asked for the whole cranberry cocktail can. That cup was about 2 sips…

I liked the boarding process with our loading group and numbers. I disliked that I couldn't guarantee our seats together. I didn't like that the Internet costs $8/ flight, but did love all the inflight options available through their app. I disliked no charging station at my seat for a 3+ hour flight.

Great! Although the flight was about 40 minutes delayed, the crew did a good job getting everything boarded quickly and efficiently.

It was as good as it could be. Flying is not a pleasant experience these days.

Bus to plane was delayed for no apparent reason and our luggage was still on the belt when they shut it off. Took about 20 minutes to turn it back on to get our luggage.

I haven’t flown economy in over 20 years but it was not bad. Room by my feet for my bag and seat was roomy enough. Surprised in a good way.

There was an unruly family behind us that made the short flight miserable!!! The cabin crew did nothing to contain it.

Flight delay was frustrating, also you cannot checkin online without delta app, web browser check-in throw errors

Second flight in a row where the entertainment system is broken. 5 hour long flight with no entertainment and flight attendants did not seem interested in resolving the matter. Very shocked to be treated this poorly considering I paid for a first class experience and have Diamond Medallion status.

The service from the flight attendants were of supreme quality. They greeted and treated everyone with a wide smile. This is totally absent nowadays. Kudos to them!!!!

My seat had no padding, it was literally plywood with a plastic cover. I could not change seats on my 10 hour flight. My excitement for this trip helped me deal with the pain.

The flights were on time- Great service Would have liked more options for food choices.

The brakes on the A220 are sensitive and uncomfortably grabby

the whole trip was smooth, and as comfortable as flying is these days. flight crew was friendly and very courteous and helpful.

Yet another flight in which beverage and snack service was skipped. Other that that, firmly mediocre. Landed early, to gate late due to congestion at the gates. Airline's fault or airports fault: unknown.

The flights were on time which was great give. It was holiday travel season and there’d been some weather issues. The only complaint and this is every time with United is the terrible seat design. The head rest is not built for comfort and having my neck bent forward for a cross country trip reminded me while I try not to take United flights as a rule.

This was a very average flight. The seat was out of alignment so more uncomfortable than usual. The cabin felt not well maintained. But I safely got where I needed to go.

We had a 90 minute delay due to equipment failure that was detected just before we took off. United rebooked my connecting flight.

Dinner was okay but the breakfast was not eatable on the flight San Francisco to Zurich.

This was a Lufthansa flight. Disappointing main meal. Very rough over Canada and arrival at FRA. IFE was almost unusable.

Poor seating comfort, seat cushion too thin, very uncomfortable. My luggage didi not make the flight due to equipment change. At least. United had it delivered the next day. I was without my toilet items for one day.

Flight cancelled because of the grounded 737s. United was good about it and got us onto a later Alaska Airlines flight to Oakland (not San Francisco as originally intended). Had to go through security again and my wife dropped her MacBook Pro, which broke, a $2,500 whoopsie. But we made it home.

I liked being upgraded to first class. The flight was a redeye, so I did sleep most of it.

Awful, tons of delays, I got into Chicago multiple hours late meaning I hit the very traffic I tried so desperately to avoid. Just empty apologies from American Airlines text alerts. Trash behavior from a trash airline.

The boarding was as always, the crew tried their best but not enough. The food was a disaster I had dietary restrictions that were half met because the company did not loaded the food for the flight. The entertainment screen was fine but content was not and also they removed the free messaging option from the flight and they charged 30 dollars for that crappy bandwidth. This flight is not worth the cost and the company is going down on quality.

As smooth as you can expect. Some issues with boarding because the previous plane took forever to deplane but overall, a good experience.

DFW-LHR Toilets not kept clean Too cramped. Aisles so narrow crew were constantly banging into people on the aisle seats. Even then, the carts used are reduced width. Other than that it was a decent flight on both legs

Excellent customer service at check in at Austin flight to DFW and excellent customer service from Karren in terminal B at DFW.

The flight itself was fine, but between the man in front of me putting his chair back, and the gentleman next to me who took up 50% of my seat, my back and neck are destroyed from the flight. I’m hoping for a better outcome flying back.

Flight boarded without pilots. Sat on plane for 3 hrs. after over an hour late boarding. Plane never took off. Had to deplane near midnight. Line for rebooking was 3 hours + long. I had to leave.

We were told there would be no food/beverage service due to turbulence. There was very little turbulence on the 2+ hour flight. I was in First Class and thought they could have done a quick service after take off as they had a quite bit of time before we would be reaching the predicted turbulent area. They could have at least passed out a quick bag of pretzels.

Very disappointed with the crew and the lack of attention given to the passengers. On a 5 hour flight they never offered a snack. One time offered a beverage and didn’t pick up the used cups until the flight was on final approach. The two flight attendants in our section mentioned that they were best friends and compared their pre flight shoes. When paying for first/business class there is a level of service that should be expected. These two spent the majority of the flight in their seats playing on their phones and laughing with each other. Very frustrating!!!

I love the Kayak has keep on updating me about flight status as it was delayed for 30mins. as well notifications to book seat and if any change on booking. Tickets were also cheap compared to British Airways online website. No hidden charges or terms n conditions. Keep it up!!!

Everything you need to know for your flight from Portland to Illinois

Information on your arrival and departure airports