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SEA - OPO

$354 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 7/4. 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
Thu 7/11
Thu 7/18

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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 44,212,782 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
7:40 am - 5:25 pmSEA-OPO
25h 45m2 stops
8:40 am - 6:26 pmOPO-SEA
17h 46m2 stops
Wed, Sep 4 - Wed, Sep 11
7:00 am - 4:15 pmSEA-OPO
25h 15m2 stops
9:55 pm - 8:50 pmOPO-SEA
30h 55m3 stops
Sat, Aug 31 - Sat, Sep 14
12:12 pm - 9:45 amSEA-OPO
13h 33m1 stop
9:00 am - 12:54 amOPO-SEA
23h 54m2 stops
$941United Airlines
Find Deal
Sun, Jul 21 - Mon, Jul 29
1:35 pm - 3:30 pmSEA-OPO
17h 55m1 stop
7:25 pm - 10:15 amOPO-SEA
22h 50m1 stop
$942KLM
Find Deal
Mon, Aug 12 - Sun, Aug 25
1:35 pm - 3:30 pmSEA-OPO
17h 55m1 stop
11:25 am - 11:57 pmOPO-SEA
20h 32m2 stops
$952Delta
Find Deal
Mon, Aug 12 - Sun, Aug 25
6:15 pm - 6:15 pmSEA-OPO
16h 00m1 stop
9:15 am - 11:53 pmOPO-SEA
22h 38m2 stops
$976Delta
Find Deal
Fri, Aug 9 - Fri, Aug 16
12:30 am - 6:55 amSEA-OPO
22h 25m2 stops
9:00 am - 12:54 amOPO-SEA
23h 54m2 stops
$991United Airlines
Find Deal
Fri, Jul 19 - Mon, Jul 29
3:15 pm - 3:40 pmSEA-OPO
16h 25m2 stops
8:30 am - 4:50 pmOPO-SEA
16h 20m1 stop
$996KLM
Find Deal
Thu, Sep 5 - Wed, Sep 11
6:50 pm - 11:20 pmSEA-OPO
20h 30m1 stop
6:15 am - 4:59 pmOPO-SEA
18h 44m1 stop
$1,176Lufthansa
Find Deal
Sun, Jul 21 - Tue, Jul 30
2:15 pm - 3:45 pmSEA-OPO
17h 30m1 stop
6:15 am - 4:59 pmOPO-SEA
18h 44m1 stop
$1,212Lufthansa
Find Deal
Tue, Jul 23 - Tue, Jul 30

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 Thursday. 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 $941 on United Airlines, followed by KLM ($942). One-way flight deals have also been found from as low as $729 on Turkish Airlines and from $778 on United Airlines.

Good to know

Low season

February

High season

September

Cheapest flight

$354
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 $354 for a one-way ticket and $904 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 $1,081 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 $1,138 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 10277 reviews
8.6Crew
7.9Comfort
8.2Boarding
7.4Food
8.0Entertainment
Airline reviews

Really bad baggage handling. Had my Rimowa bag badly damaged at the latches.

4.0 OkayDavwinder Singh, Jun 2024SEA - ATL
Read more about Delta reviews

Really bad baggage handling. Had my Rimowa bag badly damaged at the latches.

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 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.

Booked connecting flights with KlM. My serving flight was the furthest part of the airport. On arrival in Zurich. My two cases arrived but only one carry on belong to my son. His three suitcase didn't arrive. After enquiring we discovered they were still in Amsterdam. We landed at 11.12. We eventually left the airport just after one.

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.

It was nice to be on a legacy airline, people try at least.

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 entertainment wasn’t playing in the app or online.

Lady was a bit rude during boarding and I was being nice to her.

Why does it have to be painful to fly long distances?

It is a modern tragedy that any airline expects you to travel for 14 hours in such discomfort and that the only way to add comfort is exorbitant prices. I was in pain by the time we landed. Shameful.

Original plane sidelined. Had to wait an hour for replacement.

Crew was very cooperative and professional. Passenger's first checked in bag should be free.

No real agent onsite helping you for missing luggage there. Not like the other airline next to UA desk, they have staff attending in their desk assisting answer/helping luggage issue, even after midnight.

Horrible, the flights kept delaying, so it is obvious that we won't be able to make it to the next connection. No easier/real agent on site to help you figure this out. UA agent on other counters refuse to assist you and direct us to use the QR code/call customer service. So inefficient and poor. While technology seems convenient, but it's not the best interest/experience for customers need help while there is active issue need assistance.

Food is very bad and entertint not too many options ... flight attendet service is not good

After the morning frenzy of 35 min wait through CLT security at 4;30 AM, it was nice to have a smooth pleasant boarding experience. This 6:30 AM flight was not full. We were able to get seated swiftly and took off promptly. Nice touch they distributed the old fashioned headsets with 8 mm jacks. Snacks were decent and arrival was uneventful.

United delayed the flight to assist customers to make the connection. The Ohara customs area was overwhelm which created an issue for customers trying to make the Little Rock connection. The delayed allow several customers to make the final flight into Little Rock.

Missed our flight to London and we were put on coach seats to Munich.

Terrible. Missed our flight to Newark as well as our flight to London. Complete disaster

They canceled our flight last minute and we had to get another flight with twice the cost

Dinner was excellent - beef stew, the eggs for breakfast were only ok. It was soooo nice that there were so many options for movies and games.

Captain waited 45 minutes for late passengers boarding from Washington DC to Munich which was nice for them but caused our luggage to miss boarding our connection on to Bucharest. We then did not receive our luggage for about 48 hours after landing which was very inconvenient for our travel.

Poor, we had 1 hour to grab our checked luggage, go through customs, recheck bags and run across terminals to make our United flight. Poorly planned connections.

Check in in Albuquerque was awful. The people were great but they were over loaded. The procedures were terrible. We got through fine but it took 90+ minutes.

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.

Economy class has no legroom so if you have the money worth to upgrade! Food was absolutely horrible! The crew was super nice!!!!!

The flight was provided by Aer Lingus and our seats were in a poor condition (15A & 15C). They looked like they needed repairing/replacing and were uncomfortable for such a long flight. Also the arm rests on Aer Lingus planes do not lift more than around 45 degrees, instead of the usual 90 degrees upright, meaning you cannot maximum the space between you & your travel companion so as to be more comfortable for such a long flight.

Flights were actually with Aer Lingus outward and American Airlines & Aer Lingus on the return journey. Outward flight with Aer Lingus was good but the return flight with them was not so good as our seats were in a poor condition (15A & 15C) and looked like they needed replacing! The American Airlines flight from Miami to JFK New York was good and the seats were very comfortable and spacious (32D & 32E)

Awful. Delay, lost vacation time and travel time now more than 24h

Awful. Flight delayed and we missed our long flight to Rome. It has been a nightmare and we have still not arrived. It was NOT a weather delay, just poor planning by AA

Boarding was as fast and efficient as possible. The flight crew were amazing and extremely friendly. We enjoyed our flight.

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.

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.
7/4Thu
3 stops
40h 32mSEA-OPO
$354
7/4Thu
2 stops
53h 00mSEA-OPO
$370
8/4Sun
3 stops
57h 50mSEA-OPO
$383
8/1Thu
3 stops
48h 15mSEA-OPO
$427
8/27Tue
1 stopTurkish Airlines
39h 00mSEA-OPO
$729
9/7Sat
1 stopTurkish Airlines
38h 55mSEA-OPO
$769
9/1Sun
2 stopsUnited Airlines
18h 45mSEA-OPO
$778
9/7Sat
2 stopsAmerican Airlines
35h 56mSEA-OPO
$785
7/20Sat
3 stopsUnited Airlines
31h 10mSEA-OPO
$804
8/3Sat
2 stopsAmerican Airlines
31h 42mSEA-OPO
$832

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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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