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$802+ Cheap flights from Porto (OPO) to Seattle (SEA)

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 6/6. Fares are subject to change and may not be available on all flights or dates of travel.
OPO — SEA
Apr 22 — Apr 291
Tue 4/22
Tue 4/29
1 adult, Economy
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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 April 17, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$802
(Booking.com)

Popular in

June

Cheapest in

October

Average price

$836
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.
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From Porto to Seattle/Tacoma Intl
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Highest demand for flights based on searches. 20% potential increase in price ($231 potential increase over avg. RT price).
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Cheapest flight prices on average. 6% potential price decrease ($52 potential savings vs. average RT price).
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Average for round-trip flights in April 2025
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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 April 17, 2025.

This Booking.com deal was found by Cheapflights users on 4/17. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/65:55 pmOPO - SEA
1 stop27h 55mScandinavian Airlines
Sat 6/144:00 pmSEA - OPO
1 stop35h 10mScandinavian Airlines
Deal found 4/17$802
This AirNGo deal was found by Cheapflights users on 4/17. 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 AirNGo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/611:15 amOPO - SEA
1 stop32h 20mBritish Airways
Sat 6/146:24 amSEA - OPO
2 stops30h 11mBritish Airways
Deal found 4/17$834
This Delta deal was found by Cheapflights users on 4/17. 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 5/176:40 amOPO - SEA
2 stops24h 11mDelta
Sat 5/246:07 pmSEA - OPO
1 stop20h 08mDelta
Deal found 4/17$861
This United Airlines deal was found by Cheapflights users on 4/17. 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 5/1712:35 pmOPO - SEA
3 stops33h 25mUnited Airlines
Sat 5/245:14 pmSEA - OPO
2 stops29h 41mUnited Airlines
Deal found 4/17$880
This FlightHub deal was found by Cheapflights users on 4/17. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/174:50 pmOPO - SEA
1 stop32h 25mTurkish Airlines
Sat 5/247:10 pmSEA - OPO
1 stop30h 45mTurkish Airlines
Deal found 4/17$930
This Lufthansa deal was found by Cheapflights users on 4/17. 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 Lufthansa is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 6/16:15 amOPO - SEA
1 stop18h 44mLufthansa
Sun 6/86:50 pmSEA - OPO
1 stop20h 30mLufthansa
Deal found 4/17$963
This Mytrip deal was found by Cheapflights users on 4/17. 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 6/66:05 pmOPO - SEA
2 stops28h 20mMultiple Airlines
Sat 6/1410:00 amSEA - OPO
3 stops22h 30mMultiple Airlines
Deal found 4/17$1,004
This American Airlines deal was found by Cheapflights users on 4/17. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/78:15 amOPO - SEA
2 stops21h 28mAmerican Airlines
Fri 7/115:19 amSEA - OPO
2 stops18h 16mAmerican Airlines
Deal found 4/17$1,151

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 April 17, 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

Fri 6/6

5:55 pm-1:50 pm

1 stop27h 55m

Seattle/Tacoma Intl

Sat 6/14

4:00 pm-11:10 am

1 stop35h 10m

$802

PortoSeattle

OPO - SEA

OPOSEA

Porto

Fri 6/6

11:15 am-11:35 am

1 stop32h 20m

Seattle/Tacoma Intl

Sat 6/14

6:24 am-8:35 pm

2 stops30h 11m

$834

PortoSeattle

OPO - SEA

OPOSEA

Porto

Sat 5/17

6:40 am-10:51 pm

2 stops24h 11m

Seattle/Tacoma Intl

Sat 5/24

6:07 pm-10:15 pm

1 stop20h 08m

$861

PortoSeattle

OPO - SEA

OPOSEA

Porto

Sat 5/17

12:35 pm-2:00 pm

3 stops33h 25m

Seattle/Tacoma Intl

Sat 5/24

5:14 pm-6:55 am

2 stops29h 41m

$880

PortoSeattle

OPO - SEA

OPOSEA

Porto

Sat 5/17

4:50 pm-5:15 pm

1 stop32h 25m

Seattle/Tacoma Intl

Sat 5/24

7:10 pm-9:55 am

1 stop30h 45m

$930

PortoSeattle

OPO - SEA

OPOSEA

Porto

Sun 6/1

6:15 am-4:59 pm

1 stop18h 44m

Seattle/Tacoma Intl

Sun 6/8

6:50 pm-11:20 pm

1 stop20h 30m

$963

PortoSeattle

OPO - SEA

OPOSEA

Porto

Fri 6/6

6:05 pm-2:25 pm

2 stops28h 20m

Seattle/Tacoma Intl

Sat 6/14

10:00 am-4:30 pm

3 stops22h 30m

$1,004

PortoSeattle

OPO - SEA

OPOSEA

Porto

Mon 7/7

8:15 am-9:43 pm

2 stops21h 28m

Seattle/Tacoma Intl

Fri 7/11

5:19 am-7:35 am

2 stops18h 16m

$1,151

PortoSeattle

OPO - SEA

OPOSEA

Porto

Thu 7/24

12:10 pm-8:41 pm

1 stop16h 31m

$1,120

PortoSeattle

OPO - SEA

OPOSEA

Porto

Wed 10/8

10:00 pm-9:41 pm

3 stops31h 41m

$1,599

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/17

Showing 1-10 of 13 results
1
2

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 April.
ProviderPrice AccuracyTrust Score*
eDreamsPrice Accuracy3 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*2 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 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.

Cheapflights Insights

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

What is the cheapest month to book a flight from Porto to Seattle?

Currently, January is the cheapest month in which you can book a flight from Porto to Seattle (average of $238). Flying from Porto to Seattle in July is currently the most expensive (average of $411). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

Rainfall in Seattle by month

Plan your trip to Seattle by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Seattle ranges from 0.7 - 6.6 inches per month. November is typically the wettest month, when rainfall can reach 6.6 in. July is typically the driest time to visit Seattle when rainfall is around 0.7 in.

Temperature in Seattle by month

Plan your trip to Seattle by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Seattle, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 66.2 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 41.0 F).

Reviews of airlines servicing Seattle

Get insights into the airlines that provide service to Seattle. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Seattle. Reviews last updated April 17, 2025.
Delta
8.0
Very good
7,917 reviews

Entertainment

7.9

Boarding

8.2

Crew

8.5

Overall

8.0

Comfort

7.9

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Delta
8.0
Very good
7,917 reviews
Delta
8.0
Very good
7,917 reviews

Entertainment

7.9

Boarding

8.2

Crew

8.5

Overall

8.0

Comfort

7.9

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
SWISS
7.5
Good
1,580 reviews
Delta
8.0
Very good
7,917 reviews

Entertainment

7.9

Boarding

8.2

Crew

8.5

Overall

8.0

Comfort

7.9

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
United Airlines
7.4
Good
8,667 reviews
Delta
8.0
Very good
7,917 reviews

Entertainment

7.9

Boarding

8.2

Crew

8.5

Overall

8.0

Comfort

7.9

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Turkish Airlines
7.3
Good
3,769 reviews
Delta
8.0
Very good
7,917 reviews

Entertainment

7.9

Boarding

8.2

Crew

8.5

Overall

8.0

Comfort

7.9

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Scandinavian Airlines
7.3
Good
1,335 reviews
Delta
8.0
Very good
7,917 reviews

Entertainment

7.9

Boarding

8.2

Crew

8.5

Overall

8.0

Comfort

7.9

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

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.

  • What are the cheapest airlines flying from Porto to Seattle round-trip?

    Currently priced at $802, Scandinavian Airlines will fly you from Porto to Seattle and back. In addition to Scandinavian Airlines, many other airlines offer competitively priced options for your trip. Search Cheapflights for deals from Delta and British Airways - these airlines can fly you to your destination from $831 and $834, respectively. Users have found that Scandinavian Airlines is 10% cheaper than the other options available to this destination.

  • 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.

  • What is the cheapest month to book a flight from Porto to Seattle?

    Currently, January is the cheapest month in which you can book a flight from Porto to Seattle (average of $238). Flying from Porto to Seattle in July is currently the most expensive (average of $411). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Traveling to a place near Porto?

Book flights to Porto if you plan to visit one of these locations
SeaTac
Tukwila
Tacoma
Renton
Lakewood
Ocean Shores
Lacey
Leavenworth
Federal Way
Olympia
Shoreline
Cle Elum
Centralia
Aberdeen
Kent
Lynnwood
Shelton
Silverdale
Redmond
Issaquah

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Alternative routes for Porto to Seattle

See prices for flight routes from nearby airports that may be better suited for you.
Lisbon to Seattle flights
Lisbon to Portland flights

Top airline flying from Porto to Seattle

Discover the top airline that operate flights from Porto to Seattle. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated April 17, 2025.
AirlineCheapestAverageFlexibilityOn-time
KLMCheapest$756Average$848FlexibilityNo cancel feeOn-time75%

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