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SEA - OPO

$380 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 7/23. 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
Sun 6/9
Sun 6/16

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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 43,895,468 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
1:50 pm - 8:00 amSEA-OPO
34h 10m3 stops
7:00 am - 9:08 pmOPO-SEA
21h 08m2 stops
Thu, Oct 17 - Thu, Oct 31
11:10 pm - 3:45 pmSEA-OPO
32h 35m2 stops
6:15 am - 9:58 pmOPO-SEA
23h 43m2 stops
$904Air Canada
Find Deal
Mon, Jul 15 - Thu, Jul 25
11:50 pm - 7:15 pmSEA-OPO
35h 25m2 stops
8:35 pm - 11:35 amOPO-SEA
23h 00m1 stop
$998British Airways
Find Deal
Mon, Sep 9 - Sun, Sep 22
6:45 am - 9:45 amSEA-OPO
19h 00m2 stops
12:30 pm - 1:00 pmOPO-SEA
31h 30m1 stop
$1,004United Airlines
Find Deal
Thu, Oct 17 - Thu, Oct 31
11:59 pm - 6:55 amSEA-OPO
22h 56m2 stops
12:35 pm - 11:18 amOPO-SEA
30h 43m2 stops
$1,012United Airlines
Find Deal
Mon, Jul 15 - Thu, Oct 3
11:30 am - 3:30 pmSEA-OPO
20h 00m2 stops
6:30 am - 8:30 pmOPO-SEA
22h 00m2 stops
$1,061Delta
Find Deal
Sun, Jul 21 - Tue, Jul 30
6:10 pm - 9:25 pmSEA-OPO
19h 15m1 stop
8:40 pm - 10:25 amOPO-SEA
21h 45m1 stop
$1,158KLM
Find Deal
Sat, Aug 24 - Mon, Sep 2
11:50 am - 3:30 pmSEA-OPO
19h 40m2 stops
9:15 am - 5:35 pmOPO-SEA
16h 20m1 stop
$1,199Delta
Find Deal
Mon, Jul 15 - Thu, Jul 25
7:40 pm - 7:45 pmSEA-OPO
16h 05m1 stop
8:15 am - 5:45 pmOPO-SEA
17h 30m2 stops
$3,643British Airways
Find Deal
Sat, Aug 10 - Mon, Aug 19
9:15 pm - 10:15 pmSEA-OPO
17h 00m2 stops
4:20 pm - 10:15 amOPO-SEA
25h 55m1 stop
$6,340KLM
Find Deal
Sun, Aug 11 - Sat, Aug 17

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 Monday, and avoid Saturdays 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 $1,553 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 $904 on Air Canada, followed by SWISS ($915). One-way flight deals have also been found from as low as $662 on United Airlines and from $737 on Turkish Airlines.

Good to know

Low season

February

High season

September

Cheapest flight

$380
Best time to beat the crowds with an average 35% drop in price.
Most popular time to fly with an average 2% 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 $380 for a one-way ticket and $900 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 $1,138 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

Top tips for finding a cheap flight from SEA 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 10768 reviews
7.9Comfort
8.2Boarding
8.6Crew
7.4Food
8.0Entertainment
Airline reviews

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

2.0 MediocreShiva, Apr 2024SEA - SFO
Read more about Delta reviews

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 boarding process was terrible especially with an indirect flight Chicago to Seattle to San Diego was terrible talking about we overbooked a flight idk if I’d take this airline ever again we got off our flight from Chicago to Seattle and we traveled for business and they told us our connecting flight was over booked and their was no seats asking people to take a delayed next flight and they don’t tell anyone coughing to wear masks seats 30A-B were terrible during the flight no one wants to sit next to people coughing all around I don’t want to be sick traveling for work or get sick anytime it’s very upsetting the staff doesn’t take this stuff serious to tell them to wear masks when they see people coughing and sneezing

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.

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 .

I’ve had a couple flights this week on United that were delayed by an hour or more

Flight was delayed 2.5 hours - a big deal on an overnight when you plan to sleep.

I feel like they have upgraded the app since I last flew United and I found it to be super helpful. I had stopped flying United unless absolutely necessary and my experience on this trip indicates they have been working hard to improve their services.

Surprisingly easy! I was hesitant to try this, but the cost swayed me. I actually felt like I had less stress than all the taxiing and possible delays that occur with short regional flights where you spend less time in the air than getting to and from the plane..

This flight was delayed multiple times and eventually canceled around 2-3ish. Original take off time was around 10:30am. By 3, there were no other options out of Houston, so stuck in Houston for from 3pm - 11am the next day.

Should have video screens Plane audio was poor and without wired connection hard to understand crew. Should serve more than just cups of water and pretzels on six hour flight. Did not see crew rest of flight. Fix charging sockets to retain charging blocks.

I paid $380 for my one-way ticket from California to Minnesota. The fair did not include online check-in. I received instructions from their app to check in at a kiosk. At the kiosk, the boarding pass would not print until an actual person came to verify that I had a personal item and not a carry-on item, On the plane, the person next to me was drunk and allowed to continue to order alcohol. United is garbage I’d rather fly spirit.

The plane was dirty and the in seat air wasn't blowing as planes usually do.

Generally good but there wasn’t any staff available when my luggage didn’t appear at baggage claim in Fresno. It took about half an hour to locate a staff member to open up the locked room where it was being kept.

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.

German crew were very kind. Food was okay but can be better, especially bread was not good, Garbage collection was very poor.

Awful Terrible staff poor communication Flight delayed for an hour with no apology or explanation and no help re missing connecting flight. Resulted in a 7 hour layover at Munich waiting for another connecting flight. Only 15 euros refreshment voucher given. Will not fly Lufthansa again

Both flights were late for what appeared to be the airline’s not having the planes ready. Arrived over 6 hours late.

It was a busy flight and all the crew were very helpful and gracious

This flight was cancelled at the last minute. We were rebooked on another flight but a day later. We lost a day of our vacation and paid for a night in a hotel we couldn’t use. The flights we were rebooked on (both American) messed up our seating on both flights-we didn’t get the seats we had paid for. All in all, a terrible experience.

Lost our bags in Heathrow, We didn’t receive bags in Mallorca for 3 days, out of a 7 day cycling vacation. Really inconvenient and disappointing!

We missed the flight to Barcelona because the flight from Baltimore was delayed. We flew on Vueling VW6653. Our luggage didn’t arrive. Please help us get our luggage. We are staying at Hotel Gran Via in Barcelona

The seats were tiny, being of a fairly petite build, I don’t usually expect to feel crammed and cramped in a seat, but I definitely was on this flight. I couldn’t even bend over to get anything out from under the seat in front and getting up to go to the bathroom at night with the seat backs reclined was nearly impossible. I had to do gymnastics to get over and out. For an airline that does long flights overnight, it’s kind of ridiculous.

Not connecting flights. Missed my flight from Dublin to Liverpool because I arrived at Dublin one hour too late. For this mistake, they offered me a flight from Dublin to Manchester. Thats great and all, but I waste time and money to commute to Liverpool. Be sure to check the time of your connecting flights, because they sure don’t when they sell it to you

Excellent! Great flight attendants, good food (in business class, at least), very comfortable. Touchscreen and remote wasn’t great.

In economy and food was ok, but with limited leg space (and I was in a 2 seat configuration) it was difficult to eat with a tiny seat tray. I spilt wine on my trousers. First time on British Air (I usually fly Turkish Air) and in a 777. Heathrow was pleasant but changing terminals awkward.

Starting with the flight Cairo to London the plain was so poor no entertainment at all uncomfortable seats although it’s 5 hours long,then an American airline plain took me from London to Miami it was a bad experience the crew most of flight time not available and they asked us to help our selves for any snacks if we need. From Miami to London actually was perfect flight with a huge plain and perfect crew but from London to Cairo was horrible plain with stiff fixed seats not movable no entertainment or wi fi very poor Menu which is unacceptable for a business class

I've done hundreds of flights in my life, and this flight was one of the best I've ever taken, From beginning to end, everything went smoothly, professionally, and with a smile and friendly attitude from all employees I interacted with. The food was delicious (and free), as were the drinks. There was just a genial and effective way in the way that British Airways organized the flight -that reminded of days in the 70's, 80's, and 90's, when flying was a fun, and exciting adventure. I enjoyed and had confidence in the abilities of the flight crew, I'll be flying British Airways several more times this summer. Thank you so much for the great experience! Cheryl Olso

My baggage did not arrived with me. Took 3 days to get it after so may calls and follow up

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.
7/23Tue
2 stops
25h 10mSEA-OPO
$380
10/7Mon
3 stops
31h 55mSEA-OPO
$381
10/7Mon
2 stops
19h 45mSEA-OPO
$388
9/16Mon
3 stops
22h 40mSEA-OPO
$393
7/20Sat
2 stopsUnited Airlines
23h 08mSEA-OPO
$662
8/27Tue
1 stopTurkish Airlines
19h 45mSEA-OPO
$737
7/28Sun
1 stopTurkish Airlines
37h 10mSEA-OPO
$764
9/21Sat
3 stopsUnited Airlines
36h 55mSEA-OPO
$940
6/4Tue
2 stopsAmerican Airlines
31h 35mSEA-OPO
$2,975
8/26Mon
2 stopsAmerican Airlines
26h 26mSEA-OPO
$3,325

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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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