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$731+ Cheap flights from Portland, ME (PWM) to Porto (OPO)

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 11/16. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — OPO
Aug 29 — Sep 51
Sat 8/29
Sat 9/5
1 adult, Economy
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Cheap flight deals from Portland to Porto

Cheapest flights from Portland to Porto
Explore the most affordable flight options available from Portland to Porto. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 30, 2026.

This United Airlines deal was found by Cheapflights users on 7/26. 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.
Mon 11/168:45 am
PWM
-
OPO
1 stop19h 45m
United Airlines
Wed 11/1812:35 pm
OPO
-
PWM
1 stop11h 17m
United Airlines
Deal found 7/26$731
This United Airlines deal was found by Cheapflights users on 7/26. 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 9/93:43 pm
PWM
-
OPO
1 stop10h 12m
United Airlines
Wed 9/166:00 am
OPO
-
PWM
2 stops20h 23m
United Airlines
Deal found 7/26$931
This United Airlines deal was found by Cheapflights users on 7/27. 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 9/103:47 pm
PWM
-
OPO
1 stop10h 08m
United Airlines
Thu 9/176:00 am
OPO
-
PWM
2 stops17h 29m
United Airlines
Deal found 7/27$1,001
This United Airlines deal was found by Cheapflights users on 7/29. 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.
Sat 9/123:47 pm
PWM
-
OPO
1 stop12h 58m
United Airlines
Sat 9/1912:20 pm
OPO
-
PWM
2 stops35h 09m
United Airlines
Deal found 7/29$1,044
This United Airlines deal was found by Cheapflights users on 7/25. 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.
Wed 8/129:49 am
PWM
-
OPO
2 stops16h 06m
United Airlines
Fri 8/1412:35 pm
OPO
-
PWM
1 stop10h 54m
United Airlines
Deal found 7/25$1,586

Find flight deals from Portland to Porto

Discover tips and strategies to find the most affordable flight options for your journey from Portland (PWM) to Porto (OPO). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated July 30, 2026.

Most accurate provider

Ovago
3 stars

Most trusted provider

Ovago
3 stars

Round-trip from

$731
(United Airlines)
Provider with most accurate pricing for Portland-Porto flight deals.
Search Deals
Provider most trusted by Cheapflights users for Portland-Porto flights.
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From Portland to Porto
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Cheapflights Fare Finder

 
Customize your flight search to find flights from Portland to Porto 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 July 30, 2026.
Use the filters below to find and compare flights from Portland to Porto that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

PortlandPorto

PWM - OPO

PWMOPO

Portland

Mon 11/16

8:45 am-9:30 am

1 stop19h 45m

Porto

Wed 11/18

12:35 pm-6:52 pm

1 stop11h 17m

$731

PortlandPorto

PWM - OPO

PWMOPO

Portland

Sat 1/16

4:48 pm-3:20 pm

2 stops41h 32m

Porto

Wed 1/20

12:35 pm-10:57 pm

2 stops39h 22m

$766
Quickest round-trip

PortlandPorto

PWM - OPO

PWMOPO

Portland

Wed 9/9

3:43 pm-6:55 am

1 stop10h 12m

Porto

Wed 9/16

6:00 am-9:23 pm

2 stops20h 23m

$931

PortlandPorto

PWM - OPO

PWMOPO

Portland

Thu 9/10

9:49 am-9:45 am

2 stops18h 56m

Porto

Thu 9/17

6:00 am-6:29 pm

2 stops17h 29m

$1,005

PortlandPorto

PWM - OPO

PWMOPO

Portland

Sat 9/12

3:47 pm-9:45 am

1 stop12h 58m

Porto

Sat 9/19

12:20 pm-6:29 pm

2 stops35h 09m

$1,044

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/26

Sorted by cheapest first
  • Most accurate provider: When it comes to deals on Portland, Maine-Porto flights, users find the pricing of Ovago to be most consistent on Cheapflights vs. Ovago Users can find the same prices on Portland, Maine-Porto flight deals on Cheapflights vs. Ovago >95% of the time. Price accuracy is based on data collected from Portland, Maine-Porto flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Portland, Maine-Porto flights, Cheapflights users trust Ovago the most. Ovago has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Portland, Maine-Porto flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from Portland to Porto

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

Related info for your journey

Find useful and relevant information for your journey from Portland to Porto. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How long is the flight from Portland, Maine to Porto?

    For as low as $731, United Airlines can have you in Porto from Portland, Maine in 19h 45m. Portland, Maine and Porto are separated by a distance of 3071 mi.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Portland to Porto 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

Traveling to a place near Porto?

Book flights to Porto if you plan to visit one of these locations
Vila Nova de Gaia
Arcos de Valdevez
Coimbra
Aveiro

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