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$401+ 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 5/21. Fares are subject to change and may not be available on all flights or dates of travel.
OPO — ORD
Mar 8 — Mar 151
Sun 3/8
Sun 3/15
1 adult, Economy
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Cheap 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 February 6, 2026.

This Trip.com deal was found by Cheapflights users on 2/5. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/65:35 pm
OPO
-
ORD
1 stop29h 10m
Scandinavian Airlines
Sun 3/228:20 pm
ORD
-
OPO
1 stop15h 25m
Scandinavian Airlines
Deal found 2/5$533
This oojo deal was found by Cheapflights users on 2/3. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/2310:25 pm
OPO
-
ORD
1 stop23h 35m
TAP AIR PORTUGAL
Sun 4/266:00 pm
ORD
-
OPO
1 stop15h 30m
TAP AIR PORTUGAL
Deal found 2/3$575
This Rumbo deal was found by Cheapflights users on 2/3. 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 Rumbo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/58:00 pm
OPO
-
ORD
1 stop25h 25m
TAP AIR PORTUGAL
Wed 2/187:10 pm
ORD
-
OPO
1 stop11h 55m
TAP AIR PORTUGAL
Deal found 2/3$579
This Mytrip deal was found by Cheapflights users on 2/5. 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.
Fri 2/69:00 am
OPO
-
ORD
1 stop12h 25m
TAP AIR PORTUGAL
Fri 2/208:15 pm
ORD
-
OPO
1 stop31h 35m
TAP AIR PORTUGAL
Deal found 2/5$605
This Trip.com deal was found by Cheapflights users on 2/5. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/98:00 pm
OPO
-
ORD
2 stops33h 40m
Multiple Airlines
Sat 3/146:01 pm
ORD
-
OPO
1 stop14h 09m
Multiple Airlines
Deal found 2/5$622
This Mytrip deal was found by Cheapflights users on 2/5. 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.
Fri 3/66:45 pm
OPO
-
ORD
2 stops25h 35m
Multiple Airlines
Sun 3/226:20 pm
ORD
-
OPO
2 stops23h 40m
Multiple Airlines
Deal found 2/5$696
This Scandinavian Airlines deal was found by Cheapflights users on 2/3. 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 Scandinavian Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/3011:50 am
OPO
-
ORD
2 stops55h 37m
Scandinavian Airlines
Mon 4/67:15 pm
ORD
-
OPO
1 stop33h 45m
Scandinavian Airlines
Deal found 2/3$705
This Mytrip deal was found by Cheapflights users on 2/3. 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 4/238:40 pm
OPO
-
ORD
2 stops25h 20m
Multiple Airlines
Sun 4/267:25 pm
ORD
-
OPO
2 stops19h 15m
Multiple Airlines
Deal found 2/3$708
This FlightHub deal was found by Cheapflights users on 2/3. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 2/144:55 pm
OPO
-
ORD
1 stop27h 50m
TAP AIR PORTUGAL
Fri 2/208:15 pm
ORD
-
OPO
1 stop31h 35m
TAP AIR PORTUGAL
Deal found 2/3$735
This United Airlines deal was found by Cheapflights users on 2/5. 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 9/232:25 pm
OPO
-
STL
1 stop34h 16m
United Airlines
Sun 9/279:23 am
STL
-
OPO
2 stops18h 22m
United Airlines
Deal found 2/5$880
This United Airlines deal was found by Cheapflights users on 2/6. 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.
Sun 2/2212:35 pm
OPO
-
STL
2 stops16h 24m
United Airlines
Thu 2/2611:25 am
STL
-
OPO
2 stops16h 05m
United Airlines
Deal found 2/6$977
This Delta deal was found by Cheapflights users on 2/3. 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.
Wed 2/45:00 am
OPO
-
STL
2 stops17h 37m
Delta
Wed 2/1111:23 am
STL
-
OPO
2 stops17h 07m
Delta
Deal found 2/3$989

Find flight deals from Porto to Illinois

Keep the following information in mind while searching for Porto to Illinois flight deals. Data was last updated February 6, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$533
(Trip.com)

One-way from

$401
(Kiwi.com)

Popular in

August

Cheapest in

January

Average price

$652
Provider with most accurate pricing for Porto-Chicago (CHI) flight deals.
Search Deals
Provider most trusted by Cheapflights users for Porto-Chicago (CHI) flights.
Search Deals
From Porto to Illinois
Search Deals
One-way flight from Porto to Illinois
Search Deals
Highest demand for flights based on searches. 25% potential increase in price ($286 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($32 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in February 2026
Search Deals

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 February 6, 2026.
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

Fri 3/6

5:35 pm-4:45 pm

1 stop29h 10m

Chicago O'Hare Intl

Sun 3/22

8:20 pm-4:45 pm

1 stop15h 25m

$533

PortoChicago

OPO - ORD

OPOORD

Porto

Fri 3/6

6:45 pm-2:20 pm

2 stops25h 35m

Chicago O'Hare Intl

Sun 3/22

6:20 pm-11:00 pm

2 stops23h 40m

$696

PortoChicago

OPO - ORD

OPOORD

Porto

Wed 3/18

10:25 am-5:45 pm

1 stop36h 20m

Chicago O'Hare Intl

Sat 5/30

7:15 pm-5:05 pm

1 stop15h 50m

$744

PortoChicago

OPO - ORD

OPOORD

Porto

Wed 3/4

6:00 am-1:25 pm

1 stop13h 25m

Chicago O'Hare Intl

Sun 3/8

2:00 pm-9:30 am

2 stops14h 30m

$806

PortoChicago

OPO - ORD

OPOORD

Porto

Thu 3/19

12:30 pm-9:05 pm

1 stop13h 35m

Chicago O'Hare Intl

Sat 5/30

12:11 pm-6:55 am

1 stop12h 44m

$808

PortoChicago

OPO - ORD

OPOORD

Porto

Tue 3/17

6:00 am-4:20 pm

1 stop15h 20m

Chicago O'Hare Intl

Sat 5/30

12:11 pm-6:55 am

1 stop12h 44m

$808

PortoChicago

OPO - ORD

OPOORD

Porto

Tue 3/17

6:00 am-4:20 pm

1 stop15h 20m

Chicago O'Hare Intl

Wed 6/3

7:00 am-6:50 am

2 stops17h 50m

$811

PortoSt. Louis

OPO - STL

OPOSTL

Porto

Sun 2/22

12:35 pm-11:59 pm

1 stop17h 24m

Lambert-St Louis

Thu 2/26

11:39 am-9:30 am

1 stop15h 51m

$977

PortoSt. Louis

OPO - STL

OPOSTL

Porto

Sun 2/22

12:35 pm-10:59 pm

2 stops16h 24m

Lambert-St Louis

Thu 2/26

11:25 am-9:30 am

2 stops16h 05m

$977

PortoSt. Louis

OPO - STL

OPOSTL

Porto

Fri 3/20

6:00 am-2:55 pm

1 stop13h 55m

Lambert-St Louis

Fri 3/27

4:50 pm-10:25 pm

1 stop24h 35m

$1,107

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/3

Showing 1-10 of 23 results
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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
No data available for this route at this time. Please check back soon.

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 February 6, 2026.
Get a feel of what it's like to fly with KLM from Porto to Illinois by reading reviews from past customers. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
KLM
7.7
Good
1,449 reviews

Boarding

7.8

Entertainment

7.1

Crew

8.4

Overall

7.7

Comfort

7.6

Food

7.3

Reviews

1 / 20
10.0
Excellent

Snapyou,Jan 2026

TPA - LHR

Flight operated by Virgin Atlantic - usual high standard service by Virgin.
KLM
7.7
Good
1,449 reviews
KLM
7.7
Good
1,449 reviews

Boarding

7.8

Entertainment

7.1

Crew

8.4

Overall

7.7

Comfort

7.6

Food

7.3

Reviews

1 / 20
10.0
Excellent

Snapyou,Jan 2026

TPA - LHR

Flight operated by Virgin Atlantic - usual high standard service by Virgin.

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.

  • How long is the flight from Porto to Illinois?

    For as low as $806, Scandinavian Airlines can have you in Illinois from Porto in 13h 25m. The distance between Porto and Illinois is about 3931 mi. This flight may include one or multiple stops.

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

    For one-way options, check prices for American Airlines. According to our data, you can fly for as low as $484. Users have also found prices from $484 and $505 on Iberia and TAP AIR PORTUGAL, 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.

See more FAQs

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