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$383+ 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 5/20. Fares are subject to change and may not be available on all flights or dates of travel.
OPO — SEA
Apr 22 — Apr 291
Wed 4/22
Wed 4/29
1 adult, Economy
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Cheap 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 March 23, 2026.

This Mytrip deal was found by Cheapflights users on 3/22. 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 5/157:10 am
OPO
-
SEA
2 stops34h 30m
Multiple Airlines
Sun 5/243:40 pm
SEA
-
OPO
2 stops20h 50m
Multiple Airlines
Deal found 3/22$784
This Kiwi.com deal was found by Cheapflights users on 3/18. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/29:45 am
OPO
-
SEA
1 stop17h 38m
Multiple Airlines
Sat 5/97:00 pm
SEA
-
OPO
2 stops39h 30m
Multiple Airlines
Deal found 3/18$822
This Kiwi.com deal was found by Cheapflights users on 3/20. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/71:30 pm
OPO
-
SEA
1 stop37h 53m
Multiple Airlines
Wed 5/137:00 pm
SEA
-
OPO
2 stops43h 55m
Multiple Airlines
Deal found 3/20$891
This oojo deal was found by Cheapflights users on 3/18. 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.
Sat 5/26:15 am
OPO
-
SEA
1 stop19h 00m
Turkish Airlines
Sat 5/97:10 pm
SEA
-
OPO
1 stop20h 20m
Turkish Airlines
Deal found 3/18$918
This Mytrip deal was found by Cheapflights users on 3/22. 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.
Wed 5/138:25 am
OPO
-
SEA
3 stops33h 15m
Multiple Airlines
Sun 5/243:40 pm
SEA
-
OPO
3 stops25h 00m
Multiple Airlines
Deal found 3/22$935
This Mytrip deal was found by Cheapflights users on 3/22. 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 5/148:50 am
OPO
-
SEA
3 stops21h 50m
Multiple Airlines
Sun 5/243:40 pm
SEA
-
OPO
2 stops20h 50m
Multiple Airlines
Deal found 3/22$937
This Delta deal was found by Cheapflights users on 3/18. 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.
Sat 4/115:00 am
OPO
-
SEA
2 stops17h 50m
Delta
Sat 4/2512:00 pm
SEA
-
OPO
2 stops19h 25m
Delta
Deal found 3/18$939
This Mytrip deal was found by Cheapflights users on 3/18. 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.
Sat 4/115:55 am
OPO
-
SEA
3 stops24h 58m
Multiple Airlines
Sat 4/257:00 pm
SEA
-
OPO
3 stops21h 40m
Multiple Airlines
Deal found 3/18$941
This Delta deal was found by Cheapflights users on 3/18. 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.
Sat 5/25:00 am
OPO
-
SEA
2 stops19h 40m
Delta
Sat 5/99:30 am
SEA
-
OPO
2 stops17h 25m
Delta
Deal found 3/18$944
This KLM deal was found by Cheapflights users on 3/18. 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.
Sat 4/115:00 am
OPO
-
SEA
1 stop19h 30m
KLM
Sat 4/251:30 pm
SEA
-
OPO
1 stop17h 55m
KLM
Deal found 3/18$950

Find 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 March 23, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$784
(Mytrip)

One-way from

$383
(Kiwi.com)

Popular in

July

Cheapest in

May

Average price

$1,056
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. 8% potential increase in price ($93 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease ($43 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in March 2026
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 March 23, 2026.
Use the filters below to find and compare flights from Porto to Seattle that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

PortoSeattle

OPO - SEA

OPOSEA

Porto

Fri 5/15

7:10 am-9:40 am

2 stops34h 30m

Seattle/Tacoma Intl

Sun 5/24

3:40 pm-9:00 am

3 stops33h 20m

$784

PortoSeattle

OPO - SEA

OPOSEA

Porto

Thu 5/7

1:30 pm-7:23 pm

1 stop37h 53m

Seattle/Tacoma Intl

Wed 5/13

7:00 pm-10:55 pm

2 stops43h 55m

$891

PortoSeattle

OPO - SEA

OPOSEA

Porto

Sat 4/11

5:00 am-2:50 pm

2 stops17h 50m

Seattle/Tacoma Intl

Sat 4/25

12:00 pm-3:25 pm

2 stops19h 25m

$939

PortoSeattle

OPO - SEA

OPOSEA

Porto

Thu 5/7

5:00 am-11:42 am

1 stop14h 42m

Seattle/Tacoma Intl

Wed 5/13

6:40 pm-10:00 pm

1 stop19h 20m

$955

PortoSeattle

OPO - SEA

OPOSEA

Porto

Tue 9/15

6:00 am-8:03 pm

2 stops22h 03m

Seattle/Tacoma Intl

Fri 9/25

11:50 pm-9:45 am

2 stops25h 55m

$956

PortoSeattle

OPO - SEA

OPOSEA

Porto

Thu 4/2

11:25 am-11:45 am

1 stop32h 20m

Seattle/Tacoma Intl

Mon 4/6

6:40 pm-10:00 pm

1 stop19h 20m

$959

PortoSeattle

OPO - SEA

OPOSEA

Porto

Wed 9/2

6:00 am-9:56 pm

2 stops23h 56m

Seattle/Tacoma Intl

Thu 9/10

11:56 pm-6:55 am

2 stops22h 59m

$960

PortoSeattle

OPO - SEA

OPOSEA

Porto

Wed 9/2

5:00 am-2:45 pm

2 stops17h 45m

Seattle/Tacoma Intl

Thu 9/10

6:45 pm-10:00 pm

1 stop19h 15m

$966
Quickest round-trip

PortoSeattle

OPO - SEA

OPOSEA

Porto

Thu 4/2

5:00 am-11:45 am

1 stop14h 45m

Seattle/Tacoma Intl

Mon 4/6

9:00 am-10:40 am

2 stops17h 40m

$970
Cheapest one-way

PortoSeattle

OPO - SEA

OPOSEA

Porto

Tue 6/23

6:55 am-6:45 pm

2 stops19h 50m

$435

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/21

Showing 1-10 of 18 resultsSorted by cheapest first
1
2
  • 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.

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 17h 50m. Fly via Delta to get the fastest option. Porto and Seattle are separated by a distance of 5083 mi.

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

    The cheapest airlines for a one-way flight from Porto to Seattle are Lufthansa ($724), KLM ($752), and United Airlines ($948).

  • 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
Tacoma
Ocean Shores
Olympia
Kent
Lynnwood
Edmonds
Lacey
Renton
Puyallup
Kirkland
Ellensburg
Tukwila
Fife
Lakewood
Aberdeen
Shoreline
Marysville
Centralia
Federal Way

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