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Alaska Airlines(AS) flights from Seattle to Porto

Flight INFO & Alaska Airlines(AS) flights from Seattle to Porto

Cheapest one-way flight price US$358
Cheapest month December
Peak season for travel July
Flight distance 8,187.39 km

Book Alaska Airlines(AS) flights from Seattle to Porto

  • One way
  • Round-trip
      • SEA18:45
        21h 10m
        1 stops
        OPO23:55
        Seattle - Porto|Sat, Nov 7|Alaska Airlines
        US$521
        US$712
        27% off
        Search
        27% off
        US$712
        US$521
      • SEA07:10
        16h 30m
        2 stops
        OPO07:40
        Seattle - Porto|Tue, Nov 10|Alaska Airlines
        US$612
        US$712
        14% off
        Search
        14% off
        US$712
        US$612
      • SEA13:00
        16h 30m
        Nonstop
        OPO14:00
        Seattle - Porto|Mon, Sep 6|Normal Airline
        More cheap flights
        More cheap flights

Alaska Airlines(AS) flights from Seattle to Porto & Flight Schedule

Flight info.
Departure
Arrival
Weekly Schedule

  1. AS026

    Alaska Airlines

    08:00

    SEA

    5.5h

    Nonstop

    16:29

    JFK

    S M T W T F S
    Search

  2. DL138

    Delta Air Lines

    20:30

    JFK

    6.8h

    Nonstop

    07:15

    OPO

    - - - - - - S
    Search

  3. AS100

    Alaska Airlines

    18:45

    SEA

    9.6h

    Nonstop

    12:20

    LHR

    S M T W T F S
    Search

  4. BA2666

    British Airways

    08:15

    LGW

    2.7h

    Nonstop

    10:55

    OPO

    S M - W T F S
    Search

  5. AS016

    Alaska Airlines

    07:00

    SEA

    5.6h

    Nonstop

    15:36

    JFK

    S M T W T F S
    Search

  6. SN9030

    Brussels Airlines

    21:50

    EWR

    6.9h

    Nonstop

    09:45

    OPO

    S M T W T F S
    Search

  7. AS100

    Alaska Airlines

    18:45

    SEA

    9.6h

    Nonstop

    12:20

    LHR

    S M T W T F S
    Search

  8. FR1275

    Ryanair

    17:40

    STN

    2.4h

    Nonstop

    20:05

    OPO

    S M T W T F S
    Search

  9. AS100

    Alaska Airlines

    18:45

    SEA

    9.6h

    Nonstop

    12:20

    LHR

    S M T W T F S
    Search

  10. FR1261

    Ryanair

    12:10

    STN

    2.4h

    Nonstop

    14:35

    OPO

    S M T W T F S
    Search

  11. AS100

    Alaska Airlines

    18:45

    SEA

    9.6h

    Nonstop

    12:20

    LHR

    S M T W T F S
    Search

  12. FR519

    Ryanair

    06:25

    STN

    2.4h

    Nonstop

    08:50

    OPO

    S M T W T F S
    Search

  13. AS016

    Alaska Airlines

    07:00

    SEA

    5.6h

    Nonstop

    15:36

    JFK

    S M T W T F S
    Search

  14. AY5654

    Finnair

    16:55

    JFK

    7.3h

    Nonstop

    06:10

    MAD

    S M T W T F S
    Search

  15. AY4809

    Finnair

    07:20

    MAD

    1.3h

    Nonstop

    07:40

    OPO

    S M T W T F S
    Search

  16. AS100

    Alaska Airlines

    18:45

    SEA

    9.6h

    Nonstop

    12:20

    LHR

    S M T W T F S
    Search

  17. TP1361

    TAP Air Portugal

    16:35

    LHR

    2.8h

    Nonstop

    19:25

    LIS

    - - - W - - S
    Search

  18. TP1936

    TAP Air Portugal

    22:05

    LIS

    1.2h

    Nonstop

    23:15

    OPO

    S M T W T F S
    Search

  19. AS385

    Alaska Airlines

    08:20

    SEA

    4.8h

    Nonstop

    16:05

    YYZ

    S M T W T F S
    Search

  20. S4322

    SATA International

    20:45

    YYZ

    5.9h

    Nonstop

    06:40

    PDL

    S M T W T - -
    Search

  21. S4172

    SATA International

    07:15

    PDL

    2.3h

    Nonstop

    10:35

    OPO

    S M T W T F S
    Search

  22. AS100

    Alaska Airlines

    18:45

    SEA

    9.6h

    Nonstop

    12:20

    LHR

    S M T W T F S
    Search

  23. KL1010

    KLM

    14:45

    LHR

    1.3h

    Nonstop

    17:00

    AMS

    S M T W T F S
    Search

  24. KL1577

    KLM

    20:30

    AMS

    2.8h

    Nonstop

    22:15

    OPO

    S M T W T F S
    Search
Show less

Alaska Airlines(AS) flights from Seattle to Porto Flight Booking FAQ

  • When is the best time to book flights from Seattle to Porto?

    By analyzing data from all airlines on the Trip.com flight calendar, it looks like the best time to book a flight from Seattle to Porto is around 40 days (6 weeks) in advance, and the best time to fly is usually on Tuesday, Wednesday, and Saturday. Tuesday typically offers the cheapest flights for departure, while Saturday offers the best return deals.

  • When are flight tickets from Seattle (SEA) to Porto (OPO) the cheapest?

    The cheapest months to fly from Seattle to Porto is December, when demand for travel is lower.

  • Which upcoming date is cheapest to fly from Seattle to Porto on?

    After crunching the numbers on our October flight calendar, it's currently cheapest to fly from Seattle to Porto on October 25, 2026 with Lufthansa, with prices starting at US$692.

  • Is there any time difference between Seattle and Porto?

    The time difference between Porto and Seattle is 8h.

  • How do I change or cancel my ticket from Seattle to Porto?

    Tickets can only be changed or canceled if permitted by airline policy. To submit a change or cancellation request, go to the flight bookings page, select the option to change or cancel your booking, choose the relevant passengers and segment, and submit a request. Please note that additional charges may apply according to the airline ticket policy. However, if the flight has been rescheduled and you would like to change or cancel your ticket, you can submit an involuntary cancellation request. For more details about change and cancellation policies, please check the customer support pages.