$391+ Cheap flights from Porto (OPO) to Seattle (SEA)
This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 9/21. Fares are subject to change and may not be available on all flights or dates of travel.
OPO — SEA
Sep 18 — Sep 251
Round-trip
1 adult, Economy
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Find cheap flights from Porto to Seattle with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.3. Compare prices and book
Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheap flight deals from Porto to Seattle
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Best
Last-minute
One-way
Cheapest flights from Porto to SeattleExplore the most affordable flight options available from Porto to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 19, 2026.
Explore the most affordable flight options available from Porto to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 19, 2026.
This Mytrip deal was found by Cheapflights users on 8/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/136:15 am -
2 stops22h 25m
Tue 10/207:00 pm -
2 stops19h 55m
Deal found 8/17![Multiple Airlines logo]()
$812
This Mytrip deal was found by Cheapflights users on 8/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/116:35 am -
3 stops44h 10m
Sun 10/183:40 pm -
2 stops20h 50m
Deal found 8/15![Multiple Airlines logo]()
$877
This Mytrip deal was found by Cheapflights users on 8/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/1610:30 pm -
3 stops43h 10m
Wed 9/235:50 am -
3 stops29h 55m
Deal found 8/16![Multiple Airlines logo]()
$908
This Kiwi.com deal was found by Cheapflights users on 8/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/86:05 pm -
1 stop24h 10m
Tue 10/139:58 am -
1 stop16h 57m
Deal found 8/15![Multiple Airlines logo]()
$949
Best flights from Porto to SeattleDiscover carefully curated flight deals from Porto to Seattle that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated August 19, 2026.
Discover carefully curated flight deals from Porto to Seattle that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated August 19, 2026.
This Mytrip deal was found by Cheapflights users on 8/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/135:05 am -
3 stops23h 35m
Tue 10/207:00 pm -
3 stops29h 00m
Deal found 8/17![Multiple Airlines logo]()
$884
This Delta deal was found by Cheapflights users on 8/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/55:00 am -
1 stop19h 35m
Tue 9/226:45 pm -
1 stop19h 20m
Deal found 8/17![Delta logo]()
$966
This United Airlines deal was found by Cheapflights users on 8/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/156:00 am -
2 stops19h 37m
Mon 10/197:00 am -
1 stop18h 45m
Deal found 8/13![United Airlines logo]()
$997
Last-minute flights from Porto to SeattleDiscover last-minute flight deals from Porto to Seattle. Data last updated August 19, 2026 and is based on user searches.
Discover last-minute flight deals from Porto to Seattle. Data last updated August 19, 2026 and is based on user searches.
This Trip.com deal was found by Cheapflights users on 8/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/244:20 pm -
1 stop27h 17m
Sun 8/301:30 pm -
1 stop24h 30m
Deal found 8/15![Multiple Airlines logo]()
$1,017
This Delta deal was found by Cheapflights users on 8/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/2411:25 am -
1 stop32h 12m
Sun 8/301:30 pm -
1 stop18h 00m
Deal found 8/16![Delta logo]()
$1,070
This Delta deal was found by Cheapflights users on 8/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/275:00 am -
1 stop14h 37m
Tue 9/17:25 am -
2 stops19h 30m
Deal found 8/17![Delta logo]()
$971
This Mytrip deal was found by Cheapflights users on 8/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/279:45 pm -
3 stops43h 55m
Tue 9/17:00 pm -
3 stops29h 00m
Deal found 8/17![Multiple Airlines logo]()
$1,203
This Delta deal was found by Cheapflights users on 8/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/55:00 am -
1 stop19h 35m
Tue 9/226:45 pm -
1 stop19h 20m
Deal found 8/17![Delta logo]()
$966
This Mytrip deal was found by Cheapflights users on 8/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/56:55 am -
3 stops43h 50m
Tue 9/227:35 pm -
3 stops32h 20m
Deal found 8/17![Multiple Airlines logo]()
$1,074
This Mytrip deal was found by Cheapflights users on 8/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/1610:30 pm -
3 stops43h 10m
Wed 9/235:50 am -
3 stops29h 55m
Deal found 8/16![Multiple Airlines logo]()
$908
One-way flights from Porto to SeattleSearch for one-way flight options from Porto to Seattle. Find affordable one-way fares based on user searches. Data last updated August 19, 2026.
Search for one-way flight options from Porto to Seattle. Find affordable one-way fares based on user searches. Data last updated August 19, 2026.
This Kiwi.com deal was found by Cheapflights users on 8/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/218:40 pm -
3 stops45h 00m
Deal found 8/16![Multiple Airlines logo]()
$391
This Kiwi.com deal was found by Cheapflights users on 8/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/92:40 pm -
3 stops51h 00m
Deal found 8/15![Multiple Airlines logo]()
$404
This Kiwi.com deal was found by Cheapflights users on 8/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/76:50 pm -
2 stops50h 50m
Deal found 8/18![Multiple Airlines logo]()
$461
This Kiwi.com deal was found by Cheapflights users on 8/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/199:45 pm -
3 stops51h 25m
Deal found 8/17![Multiple Airlines logo]()
$492
This Kiwi.com deal was found by Cheapflights users on 8/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/510:40 pm -
3 stops50h 30m
Deal found 8/15![Multiple Airlines logo]()
$497
This Kiwi.com deal was found by Cheapflights users on 8/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/2010:00 pm -
2 stops44h 20m
Deal found 8/18![Multiple Airlines logo]()
$509
This Kiwi.com deal was found by Cheapflights users on 8/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/189:30 pm -
3 stops44h 10m
Deal found 8/15![Multiple Airlines logo]()
$525
This Kiwi.com deal was found by Cheapflights users on 8/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/119:45 pm -
3 stops51h 25m
Deal found 8/15![Multiple Airlines logo]()
$531
This Kiwi.com deal was found by Cheapflights users on 8/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/1010:05 pm -
3 stops51h 05m
Deal found 8/15![Multiple Airlines logo]()
$535
This Kiwi.com deal was found by Cheapflights users on 8/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/179:45 pm -
3 stops43h 55m
Deal found 8/18![Multiple Airlines logo]()
$546
Find flight deals from Porto to Seattle
Discover tips and strategies to find the most affordable flight options for your journey from Porto (OPO) to Seattle (SEA). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated August 19, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $812 (Mytrip) |
One-way from | $391 (Kiwi.com) |
Popular in | July |
Cheapest in | May |
Average price | $962 |
Cheapflights Fare Finder
Customize your flight search to find flights from Porto to Seattle that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated August 19, 2026.
Use the filters below to find and compare flights from Porto to Seattle that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
PortoSeattle
OPO Porto - SEA Seattle/Tacoma Intl
OPOSEA
Porto
Tue 10/13
5:05 am-8:40 pm
3 stops23h 35m
Seattle/Tacoma Intl
Tue 10/20
7:00 pm-8:00 am
3 stops29h 00m
$884
PortoSeattle
OPO Porto - SEA Seattle/Tacoma Intl
OPOSEA
Porto
Sat 9/5
5:00 am-4:35 pm
1 stop19h 35m
Seattle/Tacoma Intl
Tue 9/22
6:45 pm-10:05 pm
1 stop19h 20m
$966
Quickest round-trip
PortoSeattle
OPO Porto - SEA Seattle/Tacoma Intl
OPOSEA
Porto
Thu 10/15
6:00 am-5:37 pm
2 stops19h 37m
Seattle/Tacoma Intl
Mon 10/19
7:00 am-9:45 am
1 stop18h 45m
$997
Cheapest one-way
PortoSeattle
OPO Porto - SEA Seattle/Tacoma Intl
OPOSEA
Porto
Wed 9/9
8:25 am-9:40 am
2 stops33h 15m
$575
PortoSeattle
OPO Porto - SEA Seattle/Tacoma Intl
OPOSEA
Porto
Thu 9/17
10:20 pm-9:40 am
2 stops43h 20m
$582
PortoSeattle
OPO Porto - SEA Seattle/Tacoma Intl
OPOSEA
Porto
Mon 9/14
6:30 am-10:34 am
2 stops36h 04m
$621
PortoSeattle
OPO Porto - SEA Seattle/Tacoma Intl
OPOSEA
Porto
Sun 9/27
7:35 pm-8:44 pm
2 stops57h 09m
$725
PortoSeattle
OPO Porto - SEA Seattle/Tacoma Intl
OPOSEA
Porto
Tue 10/20
10:40 am-5:20 pm
1 stop38h 40m
$741
PortoSeattle
OPO Porto - SEA Seattle/Tacoma Intl
OPOSEA
Porto
Sat 10/24
10:45 am-6:10 pm
1 stop39h 25m
$744
PortoSeattle
OPO Porto - SEA Seattle/Tacoma Intl
OPOSEA
Porto
Mon 9/21
5:50 pm-10:37 pm
1 stop36h 47m
$796
Showing 1-10 of 11 resultsSorted by cheapest first
- Most accurate provider: When it comes to deals on Porto-Seattle flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Porto-Seattle flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Porto-Seattle flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on Porto-Seattle flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Porto-Seattle flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.
Best time to book a flight from Porto to Seattle
Have a flexible travel schedule? Discover the best time to fly to Seattle from Porto with our price prediction graph.
OPO-SEA
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.
Cheapflights Insights
Everything you need to know about your flight from Porto to Seattle
Related info for your journey
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