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$438+ 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 6/18. Fares are subject to change and may not be available on all flights or dates of travel.
OPO — SEA
Jun 3 — Jun 101
Wed 6/3
Wed 6/10
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 May 4, 2026.

This Mytrip deal was found by Cheapflights users on 5/3. 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.
Wed 6/1712:00 pm
OPO
-
SEA
2 stops36h 00m
Multiple Airlines
Wed 6/245:40 pm
SEA
-
OPO
2 stops19h 40m
Multiple Airlines
Deal found 5/3$837
This Mytrip deal was found by Cheapflights users on 4/29. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/275:05 am
OPO
-
SEA
2 stops20h 05m
Multiple Airlines
Wed 6/37:10 pm
SEA
-
OPO
1 stop18h 45m
Multiple Airlines
Deal found 4/29$917
This Delta deal was found by Cheapflights users on 5/1. 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.
Fri 5/155:00 am
OPO
-
SEA
1 stop19h 30m
Delta
Tue 5/196:40 pm
SEA
-
OPO
1 stop19h 25m
Delta
Deal found 5/1$958
This Delta deal was found by Cheapflights users on 5/3. 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.
Sun 5/175:00 am
OPO
-
SEA
1 stop14h 42m
Delta
Sat 5/236:40 pm
SEA
-
OPO
1 stop19h 20m
Delta
Deal found 5/3$960
This KLM deal was found by Cheapflights users on 5/2. 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.
Fri 5/295:00 am
OPO
-
SEA
1 stop14h 42m
Multiple Airlines
Mon 6/156:50 pm
SEA
-
OPO
1 stop19h 25m
Multiple Airlines
Deal found 5/2$961
This Kiwi.com deal was found by Cheapflights users on 4/29. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/2710:45 am
OPO
-
SEA
1 stop38h 30m
Turkish Airlines
Wed 6/37:10 pm
SEA
-
OPO
1 stop30h 30m
Turkish Airlines
Deal found 4/29$962

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 May 4, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$837
(Mytrip)

One-way from

$438
(Kiwi.com)

Popular in

March

Cheapest in

May

Average price

$823
Provider with most accurate pricing for Porto-Seattle/Tacoma Intl flight deals.
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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. 18% potential increase in price ($232 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 6% potential price decrease ($61 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in May 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 May 4, 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

Wed 5/27

5:05 am-5:10 pm

2 stops20h 05m

Seattle/Tacoma Intl

Wed 6/3

7:10 pm-9:55 pm

1 stop18h 45m

$917
Quickest round-trip

PortoSeattle

OPO - SEA

OPOSEA

Porto

Wed 5/27

5:00 am-11:42 am

1 stop14h 42m

Seattle/Tacoma Intl

Wed 6/3

1:30 pm-3:25 pm

1 stop17h 55m

$958

PortoSeattle

OPO - SEA

OPOSEA

Porto

Fri 5/15

5:00 am-4:30 pm

1 stop19h 30m

Seattle/Tacoma Intl

Tue 5/19

6:40 pm-10:05 pm

1 stop19h 25m

$958

PortoSeattle

OPO - SEA

OPOSEA

Porto

Fri 5/29

5:00 am-11:42 am

1 stop14h 42m

Seattle/Tacoma Intl

Mon 6/15

6:50 pm-10:15 pm

1 stop19h 25m

$961

PortoSeattle

OPO - SEA

OPOSEA

Porto

Wed 6/17

5:00 am-4:24 pm

1 stop19h 24m

Seattle/Tacoma Intl

Wed 6/24

5:45 pm-6:20 pm

1 stop16h 35m

$964

PortoSeattle

OPO - SEA

OPOSEA

Porto

Fri 5/29

4:20 pm-11:42 am

1 stop27h 22m

Seattle/Tacoma Intl

Sat 6/13

11:40 am-10:20 am

1 stop14h 40m

$964

PortoSeattle

OPO - SEA

OPOSEA

Porto

Sun 5/17

5:00 am-11:42 am

1 stop14h 42m

Seattle/Tacoma Intl

Sat 5/23

7:30 am-10:55 am

2 stops19h 25m

$965

PortoSeattle

OPO - SEA

OPOSEA

Porto

Wed 6/17

5:00 am-7:05 pm

2 stops22h 05m

Seattle/Tacoma Intl

Wed 6/24

5:45 pm-6:20 pm

1 stop16h 35m

$971
Cheapest one-way

PortoSeattle

OPO - SEA

OPOSEA

Porto

Sat 5/23

6:15 am-9:40 am

3 stops35h 25m

$535

PortoSeattle

OPO - SEA

OPOSEA

Porto

Mon 9/14

8:40 pm-9:09 pm

2 stops32h 29m

$598

Flights are sorted by cheapest round-trip flights first.

Deals found on 5/2

Showing 1-10 of 15 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.

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 14h 42m. 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 ($877), 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
Lynnwood
Lacey
Edmonds
Leavenworth
Snoqualmie
Tumwater
Tukwila
Puyallup
Kent
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Ellensburg
Fife
Lakewood
Issaquah
Shoreline

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