Seattle

$694+ 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 11/2. Fares are subject to change and may not be available on all flights or dates of travel.
OPO — SEA
Nov 15 — Nov 221
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1. Tell us where you want to go

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2. Select your favorite providers

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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 October 16, 2025.

This Delta deal was found by Cheapflights users on 10/15. 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 10/236:30 amOPO - SEA
1 stop17h 35mDelta
Tue 10/282:40 pmSEA - OPO
1 stop12h 50mDelta
Deal found 10/15$855
This Delta deal was found by Cheapflights users on 10/15. 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.
Mon 12/86:30 amOPO - SEA
2 stops22h 05mDelta
Fri 12/127:10 amSEA - OPO
2 stops24h 15mDelta
Deal found 10/15$1,000
This Mytrip deal was found by Cheapflights users on 10/15. 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.
Mon 12/87:45 amOPO - SEA
2 stops17h 15mMultiple Airlines
Fri 12/122:35 pmSEA - OPO
3 stops33h 35mMultiple Airlines
Deal found 10/15$1,004
This Mytrip deal was found by Cheapflights users on 10/15. 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 10/239:40 pmOPO - SEA
2 stops25h 25mMultiple Airlines
Tue 10/283:10 pmSEA - OPO
3 stops19h 50mMultiple Airlines
Deal found 10/15$1,151
This Orbitz deal was found by Cheapflights users on 10/15. 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/96:15 pmOPO - SEA
2 stops30h 45mMultiple Airlines
Sat 12/203:59 pmSEA - OPO
2 stops35h 51mMultiple Airlines
Deal found 10/15$3,489
This oojo deal was found by Cheapflights users on 10/16. 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.
Tue 12/94:10 pmOPO - SEA
1 stop32h 55mTurkish Airlines
Sat 12/207:00 pmSEA - OPO
1 stop36h 10mTurkish Airlines
Deal found 10/16$3,577

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 October 16, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$855
(KLM)

One-way from

$694
(KAYAK)

Popular in

August

Cheapest in

October

Average price

$562
Provider with most accurate pricing for Porto-Seattle/Tacoma Intl flight deals.
Provider most trusted by Cheapflights users for Porto-Seattle/Tacoma Intl flights.
From Porto to Seattle/Tacoma Intl
One-way flight from Porto to Seattle/Tacoma Intl
Highest demand for flights based on searches. 9% potential increase in price ($99 potential increase over avg. RT price).
Cheapest flight prices on average. 2% potential price decrease ($22 potential savings vs. average RT price).
Average for round-trip flights in October 2025

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 October 16, 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

Wed 2/25

4:10 pm-11:40 am

1 stop27h 30m

Seattle/Tacoma Intl

Mon 3/9

9:55 am-10:30 am

2 stops17h 35m

$855

PortoSeattle

OPO - SEA

OPOSEA

Porto

Tue 2/24

4:10 pm-11:40 am

1 stop27h 30m

Seattle/Tacoma Intl

Mon 3/9

9:55 am-10:30 am

2 stops17h 35m

$855

PortoSeattle

OPO - SEA

OPOSEA

Porto

Tue 2/24

4:10 pm-11:40 am

1 stop27h 30m

Seattle/Tacoma Intl

Mon 3/9

4:00 pm-3:25 pm

1 stop16h 25m

$861

PortoSeattle

OPO - SEA

OPOSEA

Porto

Tue 2/24

6:05 am-10:25 pm

2 stops24h 20m

Seattle/Tacoma Intl

Sun 3/8

7:20 am-10:30 am

2 stops20h 10m

$861

PortoSeattle

OPO - SEA

OPOSEA

Porto

Wed 2/25

11:15 am-11:40 am

1 stop32h 25m

Seattle/Tacoma Intl

Mon 3/9

4:00 pm-10:30 am

1 stop35h 30m

$861

PortoSeattle

OPO - SEA

OPOSEA

Porto

Tue 2/24

4:10 pm-11:40 am

1 stop27h 30m

Seattle/Tacoma Intl

Sun 3/8

4:00 pm-10:30 am

1 stop35h 30m

$861

PortoSeattle

OPO - SEA

OPOSEA

Porto

Wed 2/25

6:00 am-9:17 pm

2 stops23h 17m

Seattle/Tacoma Intl

Sun 3/8

6:20 am-9:30 am

2 stops20h 10m

$879

PortoSeattle

OPO - SEA

OPOSEA

Porto

Thu 3/26

12:30 pm-1:10 pm

1 stop31h 40m

Seattle/Tacoma Intl

Mon 3/30

7:00 am-9:45 am

2 stops18h 45m

$894

PortoSeattle

OPO - SEA

OPOSEA

Porto

Sun 11/2

10:55 am-5:05 pm

1 stop38h 10m

$694

PortoSeattle

OPO - SEA

OPOSEA

Porto

Sun 11/2

5:15 am-12:10 pm

2 stops37h 55m

$878

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/16

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 October.
ProviderPrice AccuracyTrust Score*
eDreamsPrice Accuracy3 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars

*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 FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Porto-Seattle flight deals on Cheapflights vs. FlightHub >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 FlightHub the most. FlightHub 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.

Cheapflights Insights

Everything you need to know about your flight from Porto to Seattle

How much does it cost to fly round-trip from Porto to Seattle?

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 27h 30m. Fly via KLM to get the fastest option. Porto and Seattle are separated by a distance of 5083 mi.

  • 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?

Book flights to Seattle if you plan to visit one of these locations
SeaTac
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Tacoma
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Leavenworth
Renton
Lacey
Olympia
Kent
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Issaquah
Aberdeen

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