$300 Find Cheap Flights from Portugal to Illinois

1 adult
1 adult, Economy

KAYAK searches hundreds of travel sites at once for deals on flights to Illinois

 
These are the airlines KAYAK users have selected most often from within our search results for flights to Illinois, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results for flights to Illinois, as well as popular online travel agencies
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Booking Insights

KAYAK's insights & trends for flights to Illinois

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

What is the cheapest flight to Illinois?

These are the best round-trip prices found by users searching on KAYAK in the last 72 hours.

The cheapest ticket to Illinois from Portugal found in the last 72 hours was to Chicago O'Hare Intl Airport, at $672 round-trip. The most popular route is Lisbon (LIS) to Chicago O'Hare Intl Airport (ORD) and the cheapest round-trip airline ticket found on this route in the last 72 hours was $672.

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for flights from Portugal 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 Portugal to Illinois is April, when tickets cost $721 (return) on average. On the other hand, the most expensive months are August and January, when the average cost of round-trip tickets is $1,209 and $981 respectively.

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 O'Hare Intl Airport (ORD), with an average flight price of $681.

Good to know

Low seasonMarch
Cheapest flight$300
Best time to beat the crowds with an average 11% drop in price.
Most popular time to fly and prices are also 8% lower on average.
Flight from Porto to Chicago

FAQs for booking flights from Portugal to Illinois

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

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

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

  • What is the cheapest day to fly to Illinois?

    Based on KAYAK data, the cheapest day to fly to Illinois is Thursday where round-trip tickets can be as cheap as $748. On the other hand, the most expensive day to fly is Sunday, where round-trip prices are $1,111 on average.

  • 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 $622 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 $1,209.

Reviews of the top 5 airlines serving from Portugal to Illinois

 
See real verified KAYAK customer reviews for airlines flying to Illinois. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline from Portugal to Illinois. 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 Portugal 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
DeltaOverall score based on 7954 reviews
7.9Entertainment
8.2Boarding
7.9Comfort
8.5Crew
7.3Food
Airline reviews

Perfect flight both ways. On time, courteous staff, plane comfortable and cool. Best domestic flights I’ve had in awhile.

10.0 ExcellentAnonymous, Sep 2025CLT - BOS
Read more Delta reviews

Perfect flight both ways. On time, courteous staff, plane comfortable and cool. Best domestic flights I’ve had in awhile.

Really low quality food especially for an international flight. The crew also was surprisingly unpleasant except couple of ladies. I know we were not in first class but that’s no reason to treat customers as less.

Flight delayed for two and half hours and then canceled altogether due to mechanical issues. No mechanic onsite to fix so had to send one from LAX.

Crew was good. The reservation got mixed up and they didn't have my TSA number. I am also a Silver Medallion and wasn't able to use Sky Priority.

The airport crew helped a lot, what I didn’t like? We were not informed that we needed to pick our luggage’s, if the crew at the luggage center didn’t tell me I would have been home without my belongings, I was heading out to my next connecting flight while looking for what gate to go to, I asked one of the crews for help, he told me and he also told me to not forget to grab my luggage’s which was chocking, because on my way out the country that wasn’t required, I just hope none of your customers lost their luggage’s because of this.

Delta made it easy, comfortable and timely. The crew was fantastic.

This route with Delta always has delays or is cancelled. Aircrafts seem smaller and older. I fly Delta quite a bit - haven’t had issues with the international flights. But this route has always been the troublesome one

The flight crew was friendly. I tried to adjust my seat online ahead of time but no option existed without additional fees. My friend asked at the gate about a seat change and was able to make it happen. That was great! The flight crew moved a very tall gentleman and his companion which allowed us to have more space which was nice. Overall, good experience. Appreciated the blanket and pillow.

Three seats in first class were broken and while they were able to still acommodate us it was looking very touch and go and they had others they could not acommodate

Mechanic delay in addition to a 2 hour change in takeoff time was frustrating.

My flight was delayed about 1 1/2 hours in Chicago, but other then that it was a good flight.

Flight attendant in first class gave poor service (like he didn't want to be there) and food was awful. We sat waiting for gate upon arrival over 45 mins.

Inoperable monitor left no entert for 9 hours. Crew was not helpful Food was awful.

Weather delay in Chicago?. No sense of urgency to make connection in Chicago for our connecting flight that wasn't delayed. Connection was missed.

Overall it was good. I missed my connection but I was put on another flight.

Overall a very poor experience - booked premium economy tickets but due to last minute flight delays , all my itinery went for a toss and had to fly economy class with no access to lounge or any compensation by united airlines to make up for the flight delays . i had expected better experience than that from united.

It was fine, definitely older planes with no charging or anything. There’s no entertainment set up on board, but it is nice that they allow you to access the in flight entertainment from your phone without having to pay for the Wi-Fi and they do offer free texting.

I liked that the flight was nonstop from ORD to CIU for $200 round trip.

The schedule to Moline changed 5 times. The gate changed 6 times. That is a pathetic way to run an airline. No wonder that no one in our company flies on United Express to or from Moline. Changes happen most of the time. I learned my lesson on this trip…never again!

All flight attendants could benefit by taking an international flight on Qantas Airline. Qantas attendants are much more hospitable in every way. Much superior than and attendants on any US airline.

The flight was on time and crew were nice, seats were tight and there was entertainment available

Any flight to ORD after about 2pm this summer has been challenging. Flight was delayed getting in (coming from ORD) and that led to it not leaving before a ground stop due to lightening before they could fuel the plane, and so forth. They made up some time but we were still late in arriving at ORD, and that led to missed connections.

Food was ok, but not as good as I have had before on AA.

Pretty good. The food was just mediocre, the boarding and crew were good.

Worst flight ever. I was suppose to have a 3 1/2 hour layover in Chicago but got to the gate 4 minutes before boarding.

My flight got switched and my prepaid bag didnt transfer over properly so I paid to check ANOTHER BAG. I was placed in a middle seat and it was just miserable. At least it was a bulkhead row so I had legroom. The flight just never seem3d to end

They should have MSNBC available on board. A 4- hour flight should provide more than a cookie.

Was not able to watch most shows on the entertainment site. They would not load

On Wednesday, July 30 we were in mid flight from Manchester to Charlotte and we turned around because the right engine was malfunctioning. That was the last flight out of Manchester that night. I was rebooked for Thursday, which became a weather event Friday. There were no seats left on the flight from Manchester to Charlotte. Consequently I didn’t leave Manchester until Saturday morning and we flew to Chicago so to say the least my scheduled flight and return to Iowa was three days off and it messed with my business schedule. Consequently cash flow. I would like some sort of acknowledgment of this event.

Dreadful experience. Our flight was delayed more than 8 hours due to a maintenance issue and the assistance from rebooking was poor. I was travelling with a bad knee and needed assistance waited in one place more than 3 hours before someone came with a wheelchair. The woman next to me was a 91 year old great grandmother who had waited more than 4 hours. There were moments of support from the staff but it appeared as they were going against the direction of management. It was apathy, lack of ownership and dismissive responses with small moments of kindness and understanding typically from grey haired, female, veteran staff..

Too hot. Asked for an extra glass of water and was ignored. Asked to sit in empty seats that were open because it was so hot and crowded and was denied and the seats were empty the entire flight

Terrible leg room - I’m 5’3” and my knees were touching the seat in front of me. When the person sitting in front of me leaned back, there was about 15 inches of space between my head and the TV screen which made it awkward to view movies. Last year they had decent food, but this year the only tasty item on the trip was dessert.

The flight from Cincinnati to Philadelphia was satisfactory and uneventful.

All of my Aer Lingus flights were delayed. The seat I purchased with extra leg room was exactly the same as my previous seat that was free. I would appreciate my money back.

It was fine. Not worth the premium price. Overhead bins were so high I could barely reach and no crew offered to help me. Average food. Lounge in Dublin - 51st and green- absolutely appalling. Plagued with hordes of flies, dirty, meager food and beverages. Shameful.

Dear Aer Lingus Customer Care, I am writing to formally raise a complaint regarding my recent experience on Aer Lingus flight EI53 from Dublin to Seattle on 22/08/2025. Both my wife and I were seated in 15D, 15E directly under a faulty air conditioning unit. Even though the unit was switched off, cold air continued seeping through the sides and blew directly onto us for the entire duration of the flight (over 9 hours). We reported the issue to the cabin crew, but the only attempted solution was placing a piece of food-packaging sticker over the vent. Unsurprisingly, this had no effect. When we pressed further, the crew told us: “It is hard to fix it because we don’t have an engineer on board.” As a result, my wife and I remained exposed to constant cold airflow for the whole flight, and both of us became unwell afterwards, experiencing chills, sore throat and fever at the end of the flight. This has caused significant distress, disrupted our work plans. This experience highlights both a serious maintenance issue and a lack of adequate care for passengers. We therefore request: A full investigation into the defective AC system on this aircraft. An explanation of why no effective remedy (such as reseating us) was provided. Compensation for the illness and disruption caused to both myself and my wife. We ask for a full written response within 28 days. Should this matter not be satisfactorily resolved, we are prepared to escalate the complaint to the Irish Aviation Authority and Commission for Aviation Regulation and other relevant authorities. Thank you for your urgent attention to this matter. Sincerely, Temuujin Tuvshingal Myagmarsuren Ganbold

Not JetBlue's fault but Aer Lingus never explained how to transfer to JetBlue.

Excellent as far as the flight is concerned. Faro airport passport check was a huge delay and worrisome re missing the flight. 45 minutes there through passport control

The space between seats was reduced even further. Could not even open the tray table fully and got compressed the moment the front guy reclined. For a long haul flight it was extremely uncomfortable.

Not satisfying due to loss Luguage for 4days. Damage Luguage that had no way to fill up a report for and me as a client to spend more money and time to replace it. Thank you for soliciting my opinion, but it was unfortunately a very disappointing experience. Stephanie Zvi

Check-in guidance for transfer flight, boarding, in-flight service, seat comfort, etc.

Very rude person at the boarding desk; flight attendant coughing 3 inches from my face three times- not even covering her mouth; boarding process very unacceptable for older people with stairs to all planes (are you all stuck in the 1960’s?). I am sure that I am not remembering all of the negative things, but I am sure you get the message!

Flight was fine. Second meal ( fish sandwich on hard roll) was awful. My suitcase didn’t make the flight. It had been located, but won’t be delivered until tomorrow. Five days after flight

Boarding experience was awful. TAP claims I did not have check in luggage with tickets. I went 3-4 check in agents until I finally found a helpful kind agent who checked in my luggage with no fees. On top of that our flight was over 2 hours delayed with barely an apology or explanation.

The airport temperature at the airport and on the flight was too warm

Flight being delayed for 35 minutes had me lose the connection to my transport

Was the best airplane ✈️ ever that I never see I will traveling again again with u guys.

Flight was delayed on 6/20 to miss international connection. Next flight out was 24 hours later. Not acceptable.

Flight from FNC to OBO was cancelled. We were rebooked to Lisbon later in the day. It was inconvenient but it worked out ok in the end.

Terrible flight attendant attitude. Average 3-star hotel employee has better hospitality skills. Business class seats are literally a joke. TAP executives should ride business class in other airlines to develop some rudimentary sense of what business class is.

Everything you need to know for your flight to Illinois

Cabin class types available on flights to Illinois

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

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