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$280+ Cheap flights from Seattle (SEA) to Porto (OPO)

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 3/11. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — OPO
Jan 25 — Feb 11
Sat 1/25
Sat 2/1
1 adult, Economy
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The best prices from Seattle/Tacoma Intl to Porto are usually found in November or February, booked 89 days in advance, depart on a Tuesday or Monday and return on a Monday

Cheap flight deals from Seattle to Porto

Discover tips and strategies to find the most affordable flight options for your journey from Seattle (SEA) to Porto (OPO). 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 January 20, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$669
(Mytrip)

One-way from

$355
(Kiwi.com)

Popular in

June

Cheapest in

November

Average price

$859
Provider with most accurate pricing for Seattle/Tacoma Intl-Porto flight deals.
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Provider most trusted by Cheapflights users for Seattle/Tacoma Intl-Porto flights.
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From Seattle/Tacoma Intl to Porto
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One-way flight from Seattle/Tacoma Intl to Porto
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High demand for flights, 21% potential price rise
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Best time to find cheap flights, 3% potential price drop
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Average for round-trip flights in January 2025
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Find flight deals from Seattle to Porto

Cheapest flights from Seattle to Porto
Explore the most affordable flight options available from Seattle to Porto. Find the lowest fares from popular airlines and budget airlines, with prices last updated on January 20, 2025.

This Mytrip deal was found by Cheapflights users on 1/19. 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 3/55:45 amSEA - OPO
3 stops22h 05mMultiple Airlines
Wed 3/124:45 pmOPO - SEA
2 stops27h 25mMultiple Airlines
Deal found 1/19$652
This Ticket deal was found by Cheapflights users on 1/18. 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 Ticket is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/52:10 pmSEA - OPO
1 stop34h 05mKLM
Wed 3/1211:25 amOPO - SEA
1 stop32h 15mKLM
Deal found 1/18$662
This Flysmarter deal was found by Cheapflights users on 1/19. 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 Flysmarter is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/52:00 pmSEA - OPO
1 stop17h 15mLufthansa
Wed 3/126:00 amOPO - SEA
2 stops19h 45mLufthansa
Deal found 1/19$689
This Air Canada deal was found by Cheapflights users on 1/19. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/410:35 amSEA - OPO
2 stops20h 40mAir Canada
Tue 3/116:00 amOPO - SEA
2 stops22h 30mAir Canada
Deal found 1/19$694
This United Airlines deal was found by Cheapflights users on 1/20. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/52:00 pmSEA - OPO
1 stop17h 15mUnited Airlines
Wed 3/126:00 amOPO - SEA
2 stops46h 30mUnited Airlines
Deal found 1/20$697
This SWISS deal was found by Cheapflights users on 1/19. 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 SWISS is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/512:37 pmSEA - OPO
2 stops39h 13mSWISS
Wed 3/127:20 pmOPO - SEA
2 stops34h 33mSWISS
Deal found 1/19$710
This Justfly.com deal was found by Cheapflights users on 1/19. 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 Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/2512:30 pmSEA - OPO
1 stop19h 20mTurkish Airlines
Mon 10/134:50 pmOPO - SEA
1 stop25h 45mTurkish Airlines
Deal found 1/19$790
This oojo deal was found by Cheapflights users on 1/19. 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 9/64:00 pmSEA - OPO
1 stop35h 10mScandinavian Airlines
Thu 9/116:30 amOPO - SEA
2 stops39h 30mScandinavian Airlines
Deal found 1/19$887
This Cheapflightsfares deal was found by Cheapflights users on 1/19. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/1910:38 amSEA - OPO
2 stops22h 22mTAP AIR PORTUGAL
Tue 5/2712:00 pmOPO - SEA
2 stops29h 28mTAP AIR PORTUGAL
Deal found 1/19$1,263

Find flights from Seattle to Porto within your budget

Customize your flight search to find flights from Seattle to Porto 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 January 20, 2025.

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Route

Depart

Return

Price

SeattlePorto

SEA - OPO

SEAOPO

Seattle/Tacoma Intl

Wed 3/5

5:45 am-11:50 am

3 stops22h 05m

Porto

Wed 3/12

4:45 pm-1:10 pm

2 stops27h 25m

$652

SeattlePorto

SEA - OPO

SEAOPO

Seattle/Tacoma Intl

Wed 3/5

2:10 pm-8:15 am

1 stop34h 05m

Porto

Wed 3/12

11:25 am-12:40 pm

1 stop32h 15m

$662

SeattlePorto

SEA - OPO

SEAOPO

Seattle/Tacoma Intl

Wed 3/5

2:00 pm-3:15 pm

1 stop17h 15m

Porto

Wed 3/12

6:00 am-6:45 pm

2 stops19h 45m

$675

SeattlePorto

SEA - OPO

SEAOPO

Seattle/Tacoma Intl

Tue 3/4

10:35 am-3:15 pm

2 stops20h 40m

Porto

Tue 3/11

6:00 am-9:30 pm

2 stops22h 30m

$694

SeattlePorto

SEA - OPO

SEAOPO

Seattle/Tacoma Intl

Wed 3/5

2:00 pm-3:15 pm

1 stop17h 15m

Porto

Wed 3/12

6:00 am-9:30 pm

2 stops46h 30m

$697

SeattlePorto

SEA - OPO

SEAOPO

Seattle/Tacoma Intl

Wed 3/5

12:37 pm-11:50 am

2 stops39h 13m

Porto

Wed 3/12

7:20 pm-10:53 pm

2 stops34h 33m

$710

SeattlePorto

SEA - OPO

SEAOPO

Seattle/Tacoma Intl

Sat 4/5

7:05 pm-9:45 am

1 stop30h 40m

Porto

Tue 4/15

10:45 am-5:10 pm

1 stop38h 25m

$900

SeattlePorto

SEA - OPO

SEAOPO

Seattle/Tacoma Intl

Tue 3/11

11:48 am-11:00 pm

3 stops52h 12m

$280

SeattlePorto

SEA - OPO

SEAOPO

Seattle/Tacoma Intl

Tue 3/11

7:00 am-3:15 pm

2 stops25h 15m

$520

SeattlePorto

SEA - OPO

SEAOPO

Seattle/Tacoma Intl

Tue 3/11

2:35 pm-10:35 am

1 stop13h 00m

$524

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/19

Showing 1-10 of 16 results
1
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Compare providers for flights from Seattle to Porto

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 Seattle to Porto in January.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
AranGrantPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice 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 Seattle-Porto flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Seattle-Porto flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Seattle-Porto flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Seattle-Porto 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 Seattle-Porto 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 Seattle to Porto

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

Travel insights for flights from Seattle to Porto

Get recent, data-driven insights about flights from Seattle to Porto including ideal travel times, pricing trends, and more.

How far ahead should I book a flight from Seattle to Porto?

Use this chart to determine the optimal time to book a round-trip flight from Seattle to Porto. Price data was last updated on January 17, 2025.

Booking 89 days in advance of your planned departure date is, on average, the best time to get cheap flights from Seattle to Porto. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

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

Currently, January is the cheapest month in which you can book a flight from Seattle to Porto (average of $523). Flying from Seattle to Porto in June is currently the most expensive (average of $1,083). 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.

What is the cheapest time of day to fly from SEA to OPO?

Find hourly flight availability from Seattle to Porto. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated January 20, 2025.

It’s optimal to fly from Seattle to Porto in the evening. By choosing this option you can save up to 26% on the cost of your flight, compared to a flight in the morning.

What is the cheapest day to fly from Seattle to Porto?

Use this chart to determine the cheapest time to fly round-trip from Seattle to Porto. Price data was last updated on December 16, 2024.

Travelers seeking maximum savings on their Seattle to Porto flight should consider departing on Tuesday evenings when fares are most often at their lowest. Sunday mornings flights should be avoided if possible as fares are typically the most expensive at this time.

Rainfall in Porto by month

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

In terms of precipitation, rainfall in Porto ranges from 0.7 - 7.7 inches per month. December is typically the wettest month, when rainfall can reach 7.7 in. July is typically the driest time to visit Porto when rainfall is around 0.7 in.

Temperature in Porto by month

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

If weather is an important factor for your trip to Porto, 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 68.0 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 48.2 F).

Reviews of airlines servicing Porto

Get insights into the airlines that provide service to Porto. 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 Porto. Reviews last updated January 20, 2025.
KLM
7.8
Good
1,341 reviews

Entertainment

7.2

Overall

7.8

Crew

8.4

Food

7.3

Boarding

7.8

Comfort

7.7

Reviews

1 / 10

I could not select a seat prior to check in as systems not integrated. Different PNRs should be on reservation which would make process easier.

KLM
7.8
Good
1,341 reviews
KLM
7.8
Good
1,341 reviews

Entertainment

7.2

Overall

7.8

Crew

8.4

Food

7.3

Boarding

7.8

Comfort

7.7

Reviews

1 / 10

I could not select a seat prior to check in as systems not integrated. Different PNRs should be on reservation which would make process easier.

SWISS
7.5
Good
1,599 reviews
KLM
7.8
Good
1,341 reviews

Entertainment

7.2

Overall

7.8

Crew

8.4

Food

7.3

Boarding

7.8

Comfort

7.7

Reviews

1 / 10

I could not select a seat prior to check in as systems not integrated. Different PNRs should be on reservation which would make process easier.

United Airlines
7.4
Good
8,982 reviews
KLM
7.8
Good
1,341 reviews

Entertainment

7.2

Overall

7.8

Crew

8.4

Food

7.3

Boarding

7.8

Comfort

7.7

Reviews

1 / 10

I could not select a seat prior to check in as systems not integrated. Different PNRs should be on reservation which would make process easier.

Turkish Airlines
7.3
Good
3,931 reviews
KLM
7.8
Good
1,341 reviews

Entertainment

7.2

Overall

7.8

Crew

8.4

Food

7.3

Boarding

7.8

Comfort

7.7

Reviews

1 / 10

I could not select a seat prior to check in as systems not integrated. Different PNRs should be on reservation which would make process easier.

American Airlines
7.2
Good
10,000 reviews
KLM
7.8
Good
1,341 reviews

Entertainment

7.2

Overall

7.8

Crew

8.4

Food

7.3

Boarding

7.8

Comfort

7.7

Reviews

1 / 10

I could not select a seat prior to check in as systems not integrated. Different PNRs should be on reservation which would make process easier.

Related info for your journey

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

    Our cheapest airline available from Seattle to Porto is KLM. Our recent data shows that you can find tickets from as low as $696 on this airline. Additional options worth looking into are United Airlines and Lufthansa, starting at $697 and $700 round-trip. Users have found that KLM is 37% cheaper than the other options available to this destination.

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

    $524 is the cheapest one-way deal found within the past few days, from KLM. You may also be able to find cheap deals on United Airlines and SWISS, with prices starting from $579 and $586, respectively.

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

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

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

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

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

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

    Currently, January is the cheapest month in which you can book a flight from Seattle to Porto (average of $523). Flying from Seattle to Porto in June is currently the most expensive (average of $1,083). 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.

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Traveling to a place near Seattle?

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Top 7 airlines flying from Seattle to Porto

Discover the top 7 airlines that operate flights from Seattle to Porto. 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 January 20, 2025.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$544Average$771FlexibilityNo cancel feeOn-time71%
KLMCheapest$649Average$1,127FlexibilityNo cancel feeOn-time75%
British AirwaysCheapest$673Average$1,174FlexibilityNo cancel feeOn-time70%
DeltaCheapest$674Average$1,156FlexibilityNo cancel feeOn-timeN/A
Turkish AirlinesCheapest$765Average$944FlexibilityNo cancel feeOn-time77%
LufthansaCheapest$769Average$1,185FlexibilityNo cancel feeOn-time76%
United AirlinesCheapest$851Average$1,277FlexibilityNo cancel feeOn-time69%
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