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$502+ Cheap flights from Porto (OPO) to Seattle (SEA)

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 11/20. Fares are subject to change and may not be available on all flights or dates of travel.
OPO — SEA
dic. 6 — dic. 131
sáb. 12/6
sáb. 12/13
1 adult, Economy
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Find flight deals from Porto to Seattle

Cheapest flights from Porto to Seattle
Explore the most affordable flight options available from Porto to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on noviembre 6, 2025.

This KLM deal was found by Cheapflights users on 11/5. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 11/136:35 amOPO - SEA
1 stop37h 10mMultiple Airlines
mar. 11/189:30 amSEA - OPO
2 stops17h 00mMultiple Airlines
Deal found 11/5$850
This KLM deal was found by Cheapflights users on 11/6. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 11/184:10 pmOPO - SEA
1 stop27h 35mKLM
lun. 11/242:05 pmSEA - OPO
1 stop36h 25mKLM
Deal found 11/6$852
This KLM deal was found by Cheapflights users on 11/5. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 11/1811:15 amOPO - SEA
1 stop32h 30mKLM
dom. 11/239:43 amSEA - OPO
2 stops16h 47mKLM
Deal found 11/5$853
This Delta deal was found by Cheapflights users on 11/6. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 11/186:05 amOPO - SEA
2 stops24h 18mDelta
dom. 11/237:30 amSEA - OPO
2 stops19h 00mDelta
Deal found 11/6$854
This Delta deal was found by Cheapflights users on 11/5. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 11/136:35 amOPO - SEA
2 stops23h 48mDelta
mar. 11/189:30 amSEA - OPO
2 stops17h 00mDelta
Deal found 11/5$855
This Rumbo deal was found by Cheapflights users on 11/5. 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 Rumbo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 12/204:10 pmOPO - SEA
1 stop32h 55mTurkish Airlines
sáb. 12/277:00 pmSEA - OPO
1 stop30h 55mTurkish Airlines
Deal found 11/5$940
This United Airlines deal was found by Cheapflights users on 11/5. 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.
sáb. 12/2012:30 pmOPO - SEA
2 stops40h 27mUnited Airlines
sáb. 12/277:12 pmSEA - OPO
2 stops56h 28mUnited Airlines
Deal found 11/5$961

Cheap flight deals from Porto to Seattle

Discover tips and strategies to find the most affordable flight options for your journey from Porto (OPO) to Seattle (SEA). 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 noviembre 6, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$848
(United Airlines)

One-way from

$502
(Kiwi.com)

Popular in

August

Cheapest in

October

Average price

$1,012
Provider with most accurate pricing for Porto-Seattle/Tacoma Intl flight deals.
Search Deals
Provider most trusted by Cheapflights users for Porto-Seattle/Tacoma Intl flights.
Search Deals
From Porto to Seattle/Tacoma Intl
Search Deals
One-way flight from Porto to Seattle/Tacoma Intl
Search Deals
Highest demand for flights based on searches. 9% potential increase in price ($97 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($20 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in November 2025
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Porto to Seattle 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 noviembre 6, 2025.
Use the filters below to find and compare flights from Porto to Seattle that are best for you.

Fly from

Porto

Fly to

Seattle

Route

Depart

Return

Price

PortoSeattle

OPO - SEA

OPOSEA

Porto

jue. 3/26

6:00 am-11:04 pm

2 stops24h 04m

Seattle/Tacoma Intl

lun. 3/30

5:07 am-9:45 am

2 stops20h 38m

$848

PortoSeattle

OPO - SEA

OPOSEA

Porto

mar. 11/18

4:10 pm-11:45 am

1 stop27h 35m

Seattle/Tacoma Intl

lun. 11/24

9:30 am-10:30 am

2 stops17h 00m

$850

PortoSeattle

OPO - SEA

OPOSEA

Porto

mar. 11/18

4:10 pm-11:45 am

1 stop27h 35m

Seattle/Tacoma Intl

lun. 11/24

2:05 pm-10:30 am

1 stop36h 25m

$852

PortoSeattle

OPO - SEA

OPOSEA

Porto

mar. 11/18

11:15 am-11:45 am

1 stop32h 30m

Seattle/Tacoma Intl

dom. 11/23

9:43 am-10:30 am

2 stops16h 47m

$853

PortoSeattle

OPO - SEA

OPOSEA

Porto

mar. 11/18

6:05 am-10:23 pm

2 stops24h 18m

Seattle/Tacoma Intl

dom. 11/23

7:30 am-10:30 am

2 stops19h 00m

$854

PortoSeattle

OPO - SEA

OPOSEA

Porto

mié. 11/19

6:00 am-12:01 am

2 stops26h 01m

Seattle/Tacoma Intl

dom. 11/23

7:30 am-10:30 am

2 stops19h 00m

$854

PortoSeattle

OPO - SEA

OPOSEA

Porto

mar. 11/18

6:05 am-10:29 pm

2 stops24h 24m

Seattle/Tacoma Intl

lun. 11/24

6:00 am-10:30 am

2 stops20h 30m

$854

PortoSeattle

OPO - SEA

OPOSEA

Porto

mié. 11/19

11:15 am-11:45 am

1 stop32h 30m

Seattle/Tacoma Intl

dom. 11/23

3:00 pm-3:25 pm

1 stop16h 25m

$855

PortoSeattle

OPO - SEA

OPOSEA

Porto

jue. 11/20

7:10 am-11:56 am

3 stops36h 46m

$502

PortoSeattle

OPO - SEA

OPOSEA

Porto

mié. 11/19

9:55 pm-8:46 pm

3 stops30h 51m

$548

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/4

Showing 1-10 of 15 results
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Compare providers for flights from Porto to Seattle

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Porto to Seattle in November.
ProviderPrice AccuracyTrust Score*
eDreamsPrice Accuracy3 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Porto-Seattle flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Porto-Seattle flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from Porto-Seattle flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Porto-Seattle flights, Cheapflights users trust eDreams the most. eDreams 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 Porto-Seattle 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 Porto to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle 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.

Related info for your journey

Find useful and relevant information for your journey from Porto to Seattle. 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 Porto to Seattle?

    There are many flights that can get you from Porto to Seattle in 24h 04m. Fly via United Airlines or KLM to get the fastest option. Porto and Seattle are separated by a distance of 5083 mi. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

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

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

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

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

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

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

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SeaTac
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Tukwila
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Edmonds
Leavenworth
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Kirkland
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