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SEA - OPO

$392 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 8/2. 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
Wed 6/19
Wed 6/26

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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 41,611,298 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
9:45 am - 12:50 pmSEA-OPO
19h 05m2 stops
6:00 am - 9:08 pmOPO-SEA
23h 08m2 stops
Sun, Nov 3 - Wed, Nov 13
7:05 pm - 11:35 amSEA-OPO
32h 30m2 stops
6:00 am - 9:08 pmOPO-SEA
23h 08m2 stops
Mon, Nov 4 - Wed, Nov 13
12:40 pm - 10:50 amSEA-OPO
14h 10m1 stop
11:15 am - 10:15 amOPO-SEA
31h 00m1 stop
$675Delta
Find Deal
Wed, Nov 6 - Wed, Nov 13
1:50 pm - 3:45 pmSEA-OPO
17h 55m1 stop
6:00 am - 6:59 pmOPO-SEA
20h 59m2 stops
$679Lufthansa
Find Deal
Sun, Nov 3 - Wed, Nov 13
1:50 pm - 3:45 pmSEA-OPO
17h 55m1 stop
12:30 pm - 12:00 pmOPO-SEA
31h 30m1 stop
$686United Airlines
Find Deal
Mon, Nov 4 - Tue, Nov 12
2:35 pm - 3:25 pmSEA-OPO
16h 50m1 stop
11:15 am - 10:15 amOPO-SEA
31h 00m1 stop
$689Delta
Find Deal
Sun, Nov 3 - Thu, Nov 14
11:50 pm - 3:45 pmSEA-OPO
32h 55m2 stops
12:30 pm - 12:00 pmOPO-SEA
31h 30m1 stop
$690United Airlines
Find Deal
Sat, Nov 2 - Tue, Nov 12
2:07 pm - 11:35 pmSEA-OPO
26h 28m2 stops
4:35 pm - 12:00 pmOPO-SEA
27h 25m1 stop
$696Lufthansa
Find Deal
Wed, Oct 30 - Wed, Nov 6
6:10 pm - 3:40 pmSEA-OPO
13h 30m1 stop
4:20 pm - 10:15 amOPO-SEA
25h 55m1 stop
$1,039KLM
Find Deal
Wed, Aug 7 - Wed, Aug 21
1:30 pm - 8:05 pmSEA-OPO
22h 35m1 stop
5:00 am - 3:40 pmOPO-SEA
18h 40m2 stops
$1,149KLM
Find Deal
Fri, Oct 4 - Sun, Oct 13

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 Wednesday and more expensive on a Sunday. 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 $1,700 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 $675 on Delta, followed by Lufthansa ($679). One-way flight deals have also been found from as low as $737 on Turkish Airlines and from $875 on United Airlines.

Good to know

Low season

February

High season

September

Cheapest flight

$392
Best time to beat the crowds with an average 35% drop in price.
Most popular time to fly and prices are also 0% lower on average.
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 $392 for a one-way ticket and $663 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 $1,099 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 10635 reviews
7.9Comfort
8.6Crew
8.2Boarding
8.0Entertainment
7.4Food
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.

My seat was broken. WiFi didn’t work. Gate crew at HOU were rude and condescending. Treated all the passengers badly. Bad experience, United.

First flight of the day… MINIMUM FUEL! 15 minute landing delay at HOU due to fog turned into a 2+ hour delay! Rather than circle, they had to divert to another city to refuel! Sat on tarmac at Austin to refuel. We ALL missed our connections! The crew, including pilots, were clueless. Crew was really a mess. At HOU, Untied employees were exceedingly rude to all. It was pitiful.

Food wasn’t very good, old business seating configuration on an old A340

An hour and a half late is UNACCEPTABLE. The negative impact to our family is unconscionable. And for the price we were forced to pay...

Standard flight experience, but there is only power at the seat to row 20 on the aircraft, on my initial check in it did not say that was the case

Not a fan of the diagonal partially enclosed business class seats or how they have to be converted to beds manually by crew. I prefer more isolation and user control for switching to lie flat.

No lounge access with “United First” ticket. False alarm about late flight, jeopardizing connection. Wrong meal. Loose power socket would not hold plug, could not charge device. In-flight access to text messaging did not work. Toilet seat on plane would not stay up.

We ended up with seats in the very back. So they did not recline. Have no idea why, we reserved and checked in very early. The isles were very narrow and the seats had very little leg room. But they did give us water, and a snack.

Energetic crew - flight full of swiftied going to Taylor's opening show in Paris! Long lines for bathroom made out kind of suck though

Check in etc was very good. As for on the plane, it was like flying in a freezer. It was so cold, i have flown for years and never been so cold on a plane. Staff on board said its always cold when flying which is a load of rubbish. They wouldnt put any heating on and now i have the flu because of this .

My experience would have been greatly improved by arriving on time to connect to my Porto flight. The staff that dealt with the aftermath of the late arrival evidently booked my group into a hotel in Frankfurt. This reduced my time in Porto Portugal a day and half. I do want to commend Jorge Klein for his hard work. He spent a great deal.of time trying to rebook the flight and he eventually did rebook for the next day and did provide accommodations for me overnight. This was a big issue for me and the group I traveled. The rest of the trip was good.

Not your fault…..didn’t get my drink until just before landing….bumpy flight.

Lufthansa flights were great. United flight from houston to Frankfurt had very small seats with almost no space

Second time I took this flight, and they lost my luggage both times. Waiting for my suitcase now, last time it took two days to get it back.

Everything could be better. The plain was in Orlando for 3 hours prior to boarding. After boarding all the passengers they found out that plane has a mechanical problem. After an hour the problem was solved, the pilot comes on and states, (We have to go back to the gate and take on more fuel!) Are you kidding me???? Who they have for pilots, Boy scouts?? I barely made my connecting flight to Vienna, but my suitcase did not. I'm still waiting for it, in Gyor, Hungary. Am I having fun yet?? Other passenger were in the same binned. I travelled all over the world both for business and pleasure with all types of airlines. By far of all the carriers I travelled with, Discover is the worst. I'm contemplating to bight the bullet and go back to the US with a different carrier. For International flights, the seats are made for little people. The person in front of me had his seat reclined the whole way, I felt like he was sitting in my lap. For closing, I would not let my dog travel with Discover, yet alone recommend it to an other person. Does it sound like I'm frustrated, Think about having to travel back to the US with them. I'm sure I'll not hear back from you, because nobody wants to hear about bad news, but with all the hype Discover puts out there about their services, nothing could be further from the truth. Joseph A. Nagy

Only problem we experienced was not anything to do with Lufthansa. When changing planes in Frankfurt we spent over an hour on passport control line. Lufthansa did a marvelous job on everything from keeping me informed via texts, to terrific cabin crew.

Bordón could be bettet if the company say before boarding the order of the different groups.

Checked in is easy and it was a smooth flight from LAX to Munich

There is no recline on flight from DFW to FRA. Middle eastern airways provide better recline option for the same class. FRA to Bangalore has better recline option. I bid 100$ for premium economy, my request was declined. But staff handled it without issues.

The Lufthansa part was wonderful. The short connection flight was not.

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.

Leg space was not enough. The meal was not satisfactory.

Liked that my American Airlines status seamlessly transferred to BA so luggage check was free. Flights were on time, boarding quick. Wish they didn’t assign connecting gate so late at Heathrow.

The entire process was flawless and as expected flying first class. The only thing that I have a complaint on...when first boarding, the plane was EXTREMELY cold; then when we were trying to sleep, it was way too hot - just better regulating (especially trying to sleep) would have made it perfect.

- OK plane. Basic accommodations. OK food. The digital window shade wasn't working.

- OK plane. Basic accommodations. OK food. The digital window shade wasn't working. - Expect to be woken up more than an hour before landing when they start dinging the bell and making announcements and turning on all cabin lights to serve a snack. I would prefer they remain quiet and only serve people who want to wake up.

Better food and more space in the seats. Also when doing the web check in both times I was going in to your site the minute you open it and there is not really many seats to choose only to buy!!!

It was ok, not as good as it used to be. The Heathrow connection was a disaster - complete anarchy, unknowledgable and skimpy assistance and signage. Gate crew at next flight was great, held the flight while my wife struggled through security.

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.
8/2Fri
2 stops
34h 10mSEA-OPO
$392
7/28Sun
3 stops
32h 55mSEA-OPO
$417
7/29Mon
3 stops
30h 15mSEA-OPO
$432
8/2Fri
3 stops
21h 30mSEA-OPO
$436
7/28Sun
1 stopTurkish Airlines
31h 35mSEA-OPO
$737
8/1Thu
1 stopTurkish Airlines
37h 10mSEA-OPO
$765
6/9Sun
1 stopUnited Airlines
13h 35mSEA-OPO
$875
6/24Mon
2 stopsAmerican Airlines
31h 35mSEA-OPO
$909
7/20Sat
3 stopsUnited Airlines
31h 10mSEA-OPO
$938
6/8Sat
2 stopsAmerican Airlines
27h 20mSEA-OPO
$2,975

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Seattle - Porto Flights

Departure:

Seattle (undefined)United States

Destination:

Porto (OPO)Portugal

Return flight deals:

Porto - Seattle

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