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SEA - OPO

$384 Find cheap flights from Seattle to Porto

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Seattle to Porto departing on 9/24. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
0 bags
Sat 6/29
Sat 7/6

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These are the airlines KAYAK users have selected most often from within our search results in flight searches from Seattle to Porto.
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Seattle to Porto.
In the last 7 days travelers have searched 42,686,544 times on KAYAK, and here is why:

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Cheap flight deals from Seattle to Porto (SEA-OPO)

Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Seattle to Porto that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices and deals for you by selecting your travel dates.
Choose your dates
6:45 pm - 8:00 pmSEA-OPO
17h 15m2 stops
8:20 am - 12:57 amOPO-SEA
24h 37m2 stops
$607American Airlines
Find Deal
Sun, Nov 10 - Thu, Dec 5
9:45 am - 11:15 amSEA-OPO
41h 30m2 stops
6:00 am - 9:08 pmOPO-SEA
23h 08m2 stops
Tue, Nov 12 - Thu, Dec 5
9:55 am - 3:25 pmSEA-OPO
21h 30m2 stops
6:00 am - 9:08 pmOPO-SEA
23h 08m2 stops
$664Air Canada
Find Deal
Wed, Nov 13 - Tue, Dec 3
2:00 pm - 3:25 pmSEA-OPO
17h 25m1 stop
6:05 am - 1:20 pmOPO-SEA
15h 15m1 stop
$668Lufthansa
Find Deal
Mon, Nov 11 - Fri, Dec 6
12:40 pm - 10:50 amSEA-OPO
14h 10m1 stop
11:15 am - 10:15 amOPO-SEA
31h 00m1 stop
$675Delta
Find Deal
Sun, Nov 10 - Wed, Dec 4
3:00 pm - 3:25 pmSEA-OPO
17h 25m1 stop
6:00 am - 10:22 pmOPO-SEA
24h 22m2 stops
$679United Airlines
Find Deal
Wed, Oct 30 - Wed, Nov 6
10:55 pm - 10:50 amSEA-OPO
27h 55m2 stops
11:15 am - 10:15 amOPO-SEA
31h 00m1 stop
$680Delta
Find Deal
Mon, Nov 11 - Wed, Dec 4
11:50 pm - 3:25 pmSEA-OPO
32h 35m2 stops
6:00 am - 10:22 pmOPO-SEA
24h 22m2 stops
$683United Airlines
Find Deal
Sat, Nov 2 - Tue, Nov 12
3:00 pm - 3:25 pmSEA-OPO
17h 25m1 stop
12:30 pm - 12:10 pmOPO-SEA
31h 40m1 stop
$684Lufthansa
Find Deal
Wed, Oct 30 - Wed, Nov 6
1:30 pm - 8:00 pmSEA-OPO
22h 30m1 stop
4:20 pm - 10:15 amOPO-SEA
25h 55m1 stop
$1,119KLM
Find Deal
Thu, Aug 15 - Mon, Aug 26

Flights from Seattle to Porto - Travel Insights & Trends

Get data-powered insights and trends into flights from Seattle to Porto to help you find the cheapest flights, the best time to fly and much more.

What’s the cheapest day of the week to fly from Seattle to Porto?

The average price of all flights from Seattle to Porto clicked on KAYAK for each day over the last 12 months.
Your flight ticket price will generally be cheaper if you fly to Porto on a Monday and more expensive on a Friday. On your return trip to Seattle, you should consider flying back on a Tuesday, and avoid Mondays for better deals.

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for flights from Seattle to Porto, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.
The cheapest month for flights from Seattle to Porto is February, where tickets cost $757 on average. On the other hand, the most expensive months are June and December, where the average cost of tickets is $1,689 and $1,522 respectively.

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

To calculate daily average prices, KAYAK takes all prices for each day before departure over the last year for flights from Seattle to Porto, removes the top 0.1% to account for outliers, and then takes the average of all the values for each month.
To get a below average price on the flight from Seattle to Porto, you should book around 3 days before departure. For the absolute cheapest price, our data suggests you should book 16 days before departure.

Which airlines provide the cheapest flights from Seattle to Porto?

The cheapest price for the route for each airline clicked by KAYAK users in the last 72 hours.
The cheapest return flight ticket from Seattle to Porto found by KAYAK users in the last 72 hours was for $607 on American Airlines, followed by Air Canada ($664). One-way flight deals have also been found from as low as $726 on Turkish Airlines and from $754 on TAP AIR PORTUGAL.

Good to know

Low season

February

High season

September

Cheapest flight

$384
Best time to beat the crowds with an average 34% drop in price.
Most popular time to fly with an average 4% increase in price.
Flight from Seattle to Porto

When to book flights from Seattle to Porto

Are your dates flexible? Find out the best times to travel from Seattle to Porto based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from Seattle to Porto

  • Do I need to get a visa before this flight?

    Traveling to Portugal for a stay in the Schengen area is hassle-free if your trip is for under 90 days within a 180-day timeframe. No visa is required for this duration. Keep in mind that a new 180-day period starts after spending 90 consecutive days outside the Schengen area. This allows you to enjoy your stay in Portugal without worrying about obtaining a visa.

  • What are some reasons to consider upgrading to First Class on Delta Air Lines?

    Enjoy the comfort of wider and more spacious seats and the added convenience of ticket flexibility without change fees. With Sky Priority service, your journey will be well-crafted from the beginning to the end. Indulge in a travel experience like no other, making your trip truly unforgettable in First Class.

  • What is a good choice for a sustainable airline on this trip?

    United Airlines is deeply dedicated to operating as an environmentally sustainable and responsible airline, with this commitment deeply embedded in its strategy and core principles. By the year 2050, the airline strives to achieve a remarkable goal of completely eliminating 100% of its greenhouse gas (GHG) emissions, going beyond the conventional reliance on carbon offsets. As part of its mid-term objective, United aims to reduce its carbon intensity by an impressive 50% by the year 2035, comparing against the levels recorded in 2019.

  • If I have special dietary needs, what is a good airline choice?

    On KLM, you have the convenience of ordering a customized meal that caters to your specific dietary needs. They offer various options, including low-fat, low-salt, meals suitable for diabetic, gluten-intolerance, or lactose-intolerance diets. Additionally, there is a limited number of vegetarian meals available on each flight. To ensure you receive your preferred vegetarian or vegan meal, it is advisable to place your order at least 24 h before your scheduled departure.

  • What is the cheapest flight from Seattle to Porto?

    In the last 3 days, the lowest price for a flight from Seattle to Porto was $384 for a one-way ticket and $607 for a round-trip.

  • Do I need a passport to fly between Seattle and Porto?

    Yes, you’ll need a passport to travel to Porto from Seattle.

  • Which aircraft models fly most regularly from Seattle to Porto?

    We unfortunately don’t have that data for this specific route.

  • Which airline alliances offer flights from Seattle to Porto?

    Star Alliance, oneworld, and SkyTeam are the airline alliances operating flights between Seattle and Porto, with Star Alliance being the most commonly used for this route.

  • What is the most popular layover when flying to Porto from Seattle?

    Amsterdam is the most popular layover city among KAYAK users traveling from Seattle to Porto.

  • Which is the best airline for flights from Seattle to Porto, Delta or KLM?

    The two airlines most popular with KAYAK users for flights from Seattle to Porto are Delta and KLM. With an average price for the route of $1,080 and an overall rating of 8.0, Delta is the most popular choice. KLM is also a great choice for the route, with an average price of $1,123 and an overall rating of 7.8.

  • How does KAYAK find such low prices on flights from Seattle to Porto?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Seattle to Porto.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Seattle to Porto?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Porto from Seattle is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Seattle to Porto?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Porto with an airline and back to Seattle with another airline. Booking your flights between Seattle and OPO can sometimes prove cheaper using this method.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Seattle to Porto?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Porto from Seattle up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

See more FAQs

KAYAK’s top tips for finding a cheap flight from Seattle to Porto

  • If you would like a way to Seattle Tacoma International Airport (SEA) that does not involve driving yourself, check out the 1-Line from Sound Transit that riders can take from Pioneer Square Station to the airport in about 33 minutes.
  • Because there are no direct flights available on this trip, some layover airports you can expect to use include Amsterdam Airport Schiphol (AMS), San Francisco International Airport (SFO), and Zurich Airport (ZRH).
  • When you fly with WestJet, carry-in bags can be no bigger than 21 x 9 x 15 inches, and a personal item can be no larger than 16 x 16 x 13 inches. There is no weight limit for either bag.
  • Before checking bags on Air France flights, make sure bags don't exceed linear dimensions greater than 62.2 inches, including wheels, pockets, and handles. The weight allowance for Economy Classes is a maximum of 50 lb, while Business and La Premiere Classes allow up to 70 lb.
  • When flying with American Airlines, you are permitted to bring one golf bag containing golf clubs, golf balls, golf tees, and one pair of golf shoes. It's essential to be aware that standard checked bag fees, which vary depending on your destination, will apply to bags weighing up to 50 lb and measuring up to 126 inches in total dimensions.
See more tips

Top 5 airlines serving from Seattle to Porto

 
See real verified KAYAK customer reviews for airlines flying from Seattle to Porto. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Seattle to Porto? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
8.0
DeltaOverall score based on 10457 reviews
7.9Comfort
8.0Entertainment
7.4Food
8.2Boarding
8.6Crew
Airline reviews

The plane from SNA wouldn’t start after 5 tries. The team gave me an option of flying direct from LAX and giving me a Lyft ride there! Perfect!

10.0 ExcellentSash, May 2024SEA - HNL
Read more about Delta reviews

The plane from SNA wouldn’t start after 5 tries. The team gave me an option of flying direct from LAX and giving me a Lyft ride there! Perfect!

Had a broken tray in business class. Crew just shrugged it off.

Everything was great except for the seat. The backrest would not stay in the upright position.

public website still broken for years randomly blocking browsers with privacy options active after loading a page maybe once. check-in on laptop was almost impossible but eventually randomly worked. had to print pass at airport since couldn't get back in to load digital pass on mobile firefox or chrome. red eye flight so smooth onboarding, plenty of room to spread out, easy offboarding. onboard wifi instructions mention vpn can cause problems connecting but fails to also mention private dns. no printed or built in menu list, seems weird to require personal device to point at qr code link for menu which does not even allow direct ordering. people with health condition risk related dietary restrictions trying to avoid for example cholesterol and sugar are left guessing what they can order either way without nutritional info highlights (cranberry juice was minute maid cocktail with as much suger as typical can of soda). tap to pay wasn't working and always seems sketchy to manually enter card info. good movie variety, so limited tv was okay.

Bag drop off was slow and annoying. Only 2 agents at the entire delta desk, and no one directing traffic for what line to be in, many confused people slowed down the process. Boarding was fine. Seats in Delta comfort plus were fine. Snacks were great! Definitely a bonus. The entertainment system was awful — old, slow, not responsive, and completely unable to play games due to some kind of error. But on the other hand, thank you to Delta for the free WiFi. That made it better.

Flight diverted in SD. Later take off in Seattle by 1.3hrs

Mi primera conexión se retrasó por lo cual perdí mi segunda conexión la cual salió adelantada

Crew was not friendly when I went to request a seat change.

There were choices for the snacks. Good choices and tasty lunch and breakfast as well.

The flight crew was amazing. I’m very tall and they moved me to an exit row unsolicited!!! Amazing service.

The flight was again delayed for more then 2 hours with some lousy explanation regarding the reason of the delay. Although the flight was delayed for more than 2 hours, no refreshments were offered (according to EU regulations). Last 4 flights on KLM - always at least 2 hrs late. So be prepared that you cannot plan anything with KLM.

We left one hour late because of technical difficulties. The economy comfort seats are great for the price. The crew was mediocre, they do not provide a pleasant experience, they just deliver food and drinks and give orders, not very amicable, no service and hospitality focus.

Seats are fair enough for medium tall people. Good food all the trip. Fight attendances are warm

no issues at all... Kudos to the food. This time was really really good

Overall a good experience. We were disappointed when we had to check our carry on due to the plane being full. KLM hadn’t notified us and we had valuable items in the carry on but they still made us check it. Some of the food was great and some was mediocre. Crew is really kind and funny.

One of the vstewardeses wanted to bump me of the plane for absolutely nothing. There is CCTV in the plane ans everything can be verified. Very disappointing , you all will see, o other 5 years and the passangers who does not smile to flight attendent will be bumped off...

The worst airline. Cancelled flight 30 min before boarding and rebooked on flight after 3 days.

Mostly fine. Minor delays departing and arriving. Quite a cramped plane, not so much as regards legroom but very narrow seats. Quiet nice food. Non-working USB charger. Flight attendants were helpful but not particularly proactive — one had to work to get their attention (but all was fine once they notice you), very Dutch style:)

The plane was clean and the staff was friendly. Food and drinks as expected on international flights. The entertainment system was old style, with a pullout controller, and selections not as extensive as on other flights.

I requested wheel chair assistance , it was confirmed via email that inwoood get it but I didn’t get it . The last leg of my trip to Nigeria was the worst.

Well....let's start from the point that I had to stay in airport for 12 hours instead of 2 that was scheduled. Poor company and even worst customer service. Never again....

The flight and boarding were easy peasy. I was traveling with my 4-year-old, so a smooth boarding experience was especially appreciated. My only piece of feedback is really about where our gate was in O'Hare. They've shoved four gates into a tiny corner of the B terminal and there isn't early enough room or seating for everyone. Not United's problem, but did dent the overall experience.

We liked the fully reclinable seats. Had center seats, so it was difficult to talk to spouse. Crew was great

Aisle chair was good and liked the foot bar preventing you from putting your foot in the isle, The breakfast on this international flight to Zurich was horrible (Europeans, specially, used to good food) may make this a dealbreaker for booking with United Airlines again. I agreed with my Spanish fellow passenger.

Dinner was okay but the breakfast was not eatable on the flight San Francisco to Zurich.

There was no screens on board AND the WiFi didn’t work. My seat was broken and couldn’t recline so I couldn’t even sleep. The flight attendants didn’t offer anything to make it more comfortable. It was such an old cramped plane, when the person in front of me reclined I couldn’t even open my tray table. All the United ads talk about guaranteeing everyone gets a screen!

The Wi-Fi was unavailable on this flight for some reason.

The flight was delayed almost 2 hours. Bad customer service etc. I will never fly Luthansa. Ever!!!

On time take off…US cabins look tired and need of refresh!

Fine. Though no food or entertainment so the survey needs to be updated with those options.

Will try to not fly with them again. Delays because of weather but got redirected to an airport where I could not make connection.

Staff didn’t care in business class. Closed the door on my mom while she was on the jetbridge and flight attendant told me she would make it from the connecting flight. They lied. My luggage was damaged on arrival. No success in filing damage claim.

Boston Logan is a crummy airport - signage is terrible or lacking in areas. Boarding seemed to be a free for all and with all the different airlines speaking, you couldn't tell who was supposed to be where and when. Plain and simple, airlines should board from the back of the plane to the front. Also someone was sitting in my seat. By the time that was figured out, I had to place my overhead behind me which made de-planing more difficult. Logan is not Lufthansa's fault so that is not on them, Boarding is on them! Still, overall it was a Good Experience flying with Lufthansa. This is not my first flight with them...

Overall, the flight was comfortable without any serious issues. Transit through Frankfurt airport was a little confusing, but not too difficult if you follow the signs

There was a screaming child behind our seats. This prevented us from getting any sleep during the night.

There was a screaming child just behind our seats. This prevented us from getting any sleep during the night!!

Staff disappeared after dinner service until breakfast, no help with beds, no help running to our gate to catch connection cause flight was late, our luggage didn’t make it, took over 24 hours to get luggage to hotel, no compensation!!

Everything was good except food. I believe there is room for improvement

Houston to Porto flight delayed landing made us miss our connection. Tried to get on standby for the next flight and even though the lady knew we wouldn’t be able to get on it and she sent us down there. We sat there three hours and then we’re told there’s no way you’re getting on this flight. So we had to go to customer service and ended up having to spend the night in Frankfurt and missed a whole day of our vacation in Porto

my flight was at 3:45 after that they delayed to 4:40 I have transit from Chicago to Frankfurt and Frankfurt to vina airport from vina to Erbil buy the Time I come to Frankfort my other flight left me I have to stay at airport all day with my 5 kids ask for help no one help me I spent at airport almost $450 just for food was horrible flight ever I call and ask for hotel from united customer service they been telling me we can’t provide any hotel I need some refund or fixed my flight when I return to America need some one respond my email

Very bed boarding, there was overbooked and make a lot of problems and noises

There was a problem in the luggage because there were not porters

On my way from Chicago to London, I was seated next to a quite heavy passenger. I could barely move. BA should have ensured that overweight customers are placed in comfortable seats and not to penalize also other passengers because BA is not willing to accommodate these passengers and their needs. No respect at all.

The flight as far as timings go was excellent. Unfortunately we ended up sat with someone on a night flight who had been drinking alcohol before boarding and BA staff were happily serving him more alcohol. He was very drunk which made our flight uncomfortable and awkward. My partner had this person lying on him whilst asleep. Alcohol should be served minimally. If there had been an emergency this person would not have been in a fit state to act accordingly.

First time flying with BA and I will do it again. Staff at airport and on board were very nice and helpful

they are improving. The crew from Charlotte to Tampa was outstanding. SMILING and trying to be helpful with the customers.

Wonderful service and very comfy in the bulkhead in Economy Plus! Delicious food.

The BA team at Sky Harbor is deplorable, full of unnecessary attitude and poor communication. It seems like every member of the team was looking at another to solve the problem, instead of taking agency to do so themselves. I saw no less than 6 altercations with the same gate agent where he threatened to revoke the passengers boarding pass for asking a wildly reasonable question, something as simple as where the cue to board was. I’ve complained to BA before but it seems this isn’t an issue for them, which is very disappointing

Boarding poor in London,ok in Chicago. Don’t like Heatrow/terminal5

It was very good. We got a late start by about an hour and a half. However I worked rather have that than crash. It was purely mechanical. They had our tickets ready when we came off the plane in London for the next leg. The only mishap was when we got to Lisbon my husbands luggage made or bit mine didn't. All was not lost because I did finally get it 2 days later. I was really pleased that they c made the effort.

Book cheap flights from Seattle to Porto

Recent one-way flight deals

 
Only flying one-way? Below are some of the best one-way flight deals from Seattle to Porto found on KAYAK in the last 72 hours.
9/24Tue
2 stops
21h 00mSEA-OPO
$384
6/10Mon
3 stops
51h 11mSEA-OPO
$459
9/24Tue
3 stops
30h 15mSEA-OPO
$478
8/27Tue
1 stopTurkish Airlines
37h 10mSEA-OPO
$726
9/1Sun
1 stopTurkish Airlines
37h 10mSEA-OPO
$729
9/21Sat
2 stopsTAP AIR PORTUGAL
31h 54mSEA-OPO
$754
6/9Sun
2 stopsAmerican Airlines
26h 45mSEA-OPO
$785
7/20Sat
2 stopsAmerican Airlines
28h 48mSEA-OPO
$811
7/20Sat
3 stopsUnited Airlines
31h 10mSEA-OPO
$953
7/19Fri
2 stopsUnited Airlines
22h 25mSEA-OPO
$1,003

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Last minute flights from Seattle to Porto

Last minute flight, train and bus deals

 
These last-minute flight deals are the cheapest flights found on KAYAK in the last 72 hours for flights from Seattle to Porto that are departing in the next 10 days.
6/4Tue
multi-stopTurkish Airlines
32h 35mSEA-OPO
6/21Fri
multi-stopTurkish Airlines
38h 00mOPO-SEA
$5,995
6/4Tue
multi-stopLufthansa
17h 30mSEA-OPO
6/21Fri
multi-stopLufthansa
24h 05mOPO-SEA
$7,245
6/4Tue
multi-stopLufthansa
18h 35mSEA-OPO
6/21Fri
multi-stopLufthansa
20h 26mOPO-SEA
$7,252
6/3Mon
multi-stopAmerican Airlines
26h 30mSEA-OPO
6/21Fri
multi-stopAmerican Airlines
24h 32mOPO-SEA
$8,483

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Seattle - Porto Flights

Departure:

Seattle (SEA)United States

Destination:

Porto (OPO)Portugal

Return flight deals:

Porto - Seattle

Cabin classes:

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