Illinois

$315+ Cheap flights from Porto (OPO) 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 6/4. Fares are subject to change and may not be available on all flights or dates of travel.
OPO — ORD
Apr 30 — May 71
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Cheap flight deals from Porto to Illinois

Keep the following information in mind while searching for Porto to Illinois flight deals. Data was last updated April 25, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
2 stars

Round-trip from

$689
(Delta)

One-way from

$315
(Kiwi.com)

Popular in

July

Cheapest in

March

Average price

$682
Provider with most accurate pricing for Porto-Chicago (CHI) flight deals.
Provider most trusted by Cheapflights users for Porto-Chicago (CHI) flights.
From Porto to Illinois
One-way flight from Porto to Illinois
Highest demand for flights based on searches. 13% potential increase in price ($128 potential increase over avg. RT price).
Cheapest flight prices on average. 3% potential price decrease ($26 potential savings vs. average RT price).
Average for round-trip flights in April 2025

Find flight deals from Porto to Illinois

Cheapest flights from Porto to Illinois
Explore the most affordable flight options available from Porto to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on April 25, 2025.

This Delta deal was found by Cheapflights users on 4/25. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/156:30 amOPO - ORD
1 stop13h 40mDelta
Thu 5/297:00 amORD - OPO
2 stops19h 25mDelta
Deal found 4/25$689
This KLM deal was found by Cheapflights users on 4/25. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/126:30 amOPO - ORD
1 stop13h 40mKLM
Tue 6/244:20 pmORD - OPO
1 stop12h 20mKLM
Deal found 4/25$696
This British Airways deal was found by Cheapflights users on 4/25. 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 British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/157:30 pmOPO - ORD
1 stop22h 15mBritish Airways
Thu 5/2910:25 pmORD - OPO
1 stop15h 55mBritish Airways
Deal found 4/25$722
This AirNGo deal was found by Cheapflights users on 4/25. 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 AirNGo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/1010:35 pmOPO - ORD
1 stop23h 55mTAP AIR PORTUGAL
Fri 10/176:00 pmORD - OPO
1 stop24h 40mTAP AIR PORTUGAL
Deal found 4/25$765
This Lufthansa deal was found by Cheapflights users on 4/25. 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 Lufthansa is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/276:15 amOPO - ORD
1 stop18h 10mLufthansa
Mon 12/2910:35 pmORD - OPO
1 stop17h 50mLufthansa
Deal found 4/25$792
This Mytrip deal was found by Cheapflights users on 4/25. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/1510:25 pmOPO - ORD
3 stops28h 50mMultiple Airlines
Wed 5/287:25 pmORD - OPO
2 stops22h 20mMultiple Airlines
Deal found 4/25$826
This American Airlines deal was found by Cheapflights users on 4/25. 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.
Fri 10/108:15 amOPO - ORD
2 stops17h 15mAmerican Airlines
Fri 10/174:30 pmORD - OPO
1 stop13h 10mAmerican Airlines
Deal found 4/25$837
This United Airlines deal was found by Cheapflights users on 4/25. 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 5/156:00 amOPO - ORD
1 stop12h 55mUnited Airlines
Wed 5/288:45 amORD - OPO
1 stop16h 15mUnited Airlines
Deal found 4/25$855

Cheapflights Fare Finder

Customize your flight search to find flights from Porto 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 April 25, 2025.
Use the filters below to find and compare flights from Porto to Illinois that are best for you.

Fly from

Porto

Fly to

Illinois

Route

Depart

Return

Price

PortoChicago

OPO - ORD

OPOORD

Porto

Thu 5/15

6:30 am-2:10 pm

1 stop13h 40m

Chicago O'Hare Intl

Thu 5/29

7:00 am-8:25 am

2 stops19h 25m

$689

PortoChicago

OPO - ORD

OPOORD

Porto

Thu 6/12

6:30 am-2:10 pm

1 stop13h 40m

Chicago O'Hare Intl

Tue 6/24

4:20 pm-10:40 am

1 stop12h 20m

$696

PortoChicago

OPO - ORD

OPOORD

Porto

Thu 5/15

7:30 pm-11:45 am

1 stop22h 15m

Chicago O'Hare Intl

Thu 5/29

10:25 pm-8:20 pm

1 stop15h 55m

$722

PortoChicago

OPO - ORD

OPOORD

Porto

Fri 10/10

10:35 pm-4:30 pm

1 stop23h 55m

Chicago O'Hare Intl

Fri 10/17

6:00 pm-12:40 am

1 stop24h 40m

$765

PortoChicago

OPO - ORD

OPOORD

Porto

Thu 5/15

10:25 pm-9:15 pm

3 stops28h 50m

Chicago O'Hare Intl

Wed 5/28

7:25 pm-11:45 pm

2 stops22h 20m

$826

PortoChicago

OPO - ORD

OPOORD

Porto

Fri 10/10

8:15 am-7:30 pm

2 stops17h 15m

Chicago O'Hare Intl

Fri 10/17

4:30 pm-11:40 am

1 stop13h 10m

$837

PortoChicago

OPO - ORD

OPOORD

Porto

Thu 5/15

6:00 am-12:55 pm

1 stop12h 55m

Chicago O'Hare Intl

Wed 5/28

8:45 am-7:00 am

1 stop16h 15m

$855

PortoChicago

OPO - ORD

OPOORD

Porto

Wed 6/4

7:40 am-6:32 am

2 stops28h 52m

$315

PortoSt. Louis

OPO - STL

OPOSTL

Porto

Tue 9/9

6:55 pm-6:38 pm

3 stops53h 43m

$546

PortoChicago

OPO - ORD

OPOORD

Porto

Fri 7/4

4:50 pm-9:40 am

1 stop22h 50m

$606

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/25

Showing 1-10 of 15 results
1
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Best time to book a flight from Porto to Illinois

Have a flexible travel schedule? Discover the best time to fly to Illinois from Porto 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 Porto to Illinois

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

Currently, August is the cheapest month in which you can book a flight from Porto to Illinois (average of $245). Flying from Porto 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.

Rainfall in Illinois by month

Plan your trip to Illinois by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Illinois ranges from 1.7 - 4.9 inches per month. August is typically the wettest month, when rainfall can reach 4.9 in. January is typically the driest time to visit Illinois when rainfall is around 1.7 in.

Temperature in Illinois by month

Plan your trip to Illinois by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Illinois, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 73.4 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 23.0 F).

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 April 25, 2025.
8.0
Very good

Comfort

7.9

Boarding

8.2

Crew

8.5

Overall

8.0

Entertainment

7.9

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
8.0
Very good
8.0
Very good

Comfort

7.9

Boarding

8.2

Crew

8.5

Overall

8.0

Entertainment

7.9

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
8.0
Very good

Comfort

7.9

Boarding

8.2

Crew

8.5

Overall

8.0

Entertainment

7.9

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
8.0
Very good

Comfort

7.9

Boarding

8.2

Crew

8.5

Overall

8.0

Entertainment

7.9

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
8.0
Very good

Comfort

7.9

Boarding

8.2

Crew

8.5

Overall

8.0

Entertainment

7.9

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
8.0
Very good

Comfort

7.9

Boarding

8.2

Crew

8.5

Overall

8.0

Entertainment

7.9

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

Related info for your journey

Find useful and relevant information for your journey from Porto to Illinois. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
  • What airport do you fly from for flights from Porto to Illinois?

    Porto (OPO), located 6.8 mi from the city center, is the airport you fly out of when you book flights from Porto to Illinois.

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

    For one-way options, check prices for Turkish Airlines. According to our data, you can fly for as low as $606. Users have also found prices from $711 and $922 on Iberia and United Airlines, respectively.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Porto 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 Porto to Illinois?

    Currently, August is the cheapest month in which you can book a flight from Porto to Illinois (average of $245). Flying from Porto 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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