$326+ Cheap flights from Seattle (SEA) to Porto (OPO)
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 8/11. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — OPO
Jun 12 — Jun 191
Round-trip
1 adult, Economy
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Find cheap flights from Seattle to Porto 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
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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 Seattle to Porto
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Best
Last-minute
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Cheapest flights from Seattle to PortoExplore the most affordable flight options available from Seattle to Porto. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 13, 2026.
Explore the most affordable flight options available from Seattle to Porto. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 13, 2026.
This Lufthansa deal was found by Cheapflights users on 5/10. 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 Lufthansa is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/26:50 pm
SEA
- OPO
1 stop20h 35m
Lufthansa
Fri 10/166:20 am
OPO
- SEA
1 stop18h 39m
Lufthansa
Deal found 5/10![Lufthansa logo]()
$621
This Orbitz deal was found by Cheapflights users on 5/13. 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/96:50 pm
SEA
- OPO
2 stops28h 50m
Iberia
Mon 11/239:55 pm
OPO
- SEA
2 stops27h 00m
Iberia
Deal found 5/13![Iberia logo]()
$775
This Justfly.com deal was found by Cheapflights users on 5/11. 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 Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 11/87:20 am
SEA
- OPO
2 stops19h 45m
Scandinavian Airlines
Mon 11/2311:55 am
OPO
- SEA
2 stops42h 16m
Scandinavian Airlines
Deal found 5/11![Scandinavian Airlines logo]()
$778
This Scandinavian Airlines deal was found by Cheapflights users on 5/11. 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 Scandinavian Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/177:20 am
SEA
- OPO
2 stops19h 45m
Scandinavian Airlines
Fri 11/205:45 pm
OPO
- SEA
2 stops36h 19m
Scandinavian Airlines
Deal found 5/11![Scandinavian Airlines logo]()
$782
This oojo deal was found by Cheapflights users on 5/10. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/77:10 pm
SEA
- OPO
1 stop30h 30m
Turkish Airlines
Thu 10/1511:00 am
OPO
- SEA
1 stop38h 15m
Turkish Airlines
Deal found 5/10![Turkish Airlines logo]()
$792
This British Airways deal was found by Cheapflights users on 5/10. 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 British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/71:30 pm
SEA
- OPO
1 stop21h 35m
British Airways
Thu 10/158:20 am
OPO
- SEA
2 stops23h 54m
British Airways
Deal found 5/10![British Airways logo]()
$795
This American Airlines deal was found by Cheapflights users on 5/12. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/1112:00 pm
SEA
- OPO
2 stops20h 00m
American Airlines
Wed 10/218:20 am
OPO
- SEA
2 stops19h 10m
American Airlines
Deal found 5/12![American Airlines logo]()
$799
This American Airlines deal was found by Cheapflights users on 5/10. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/512:57 pm
SEA
- OPO
2 stops19h 03m
American Airlines
Wed 10/1412:25 pm
OPO
- SEA
2 stops19h 50m
American Airlines
Deal found 5/10![American Airlines logo]()
$800
This KAYAK deal was found by Cheapflights users on 5/13. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/113:10 pm
SEA
- OPO
1 stop24h 45m
Lufthansa
Fri 11/206:15 am
OPO
- SEA
1 stop15h 05m
Lufthansa
Deal found 5/13![Lufthansa logo]()
$807
This United Airlines deal was found by Cheapflights users on 5/12. 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.
Wed 10/217:00 am
SEA
- OPO
1 stop18h 45m
United Airlines
Wed 12/1612:30 pm
OPO
- SEA
2 stops20h 03m
United Airlines
Deal found 5/12![United Airlines logo]()
$812
Best flights from Seattle to PortoDiscover carefully curated flight deals from Seattle to Porto that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated May 13, 2026.
Discover carefully curated flight deals from Seattle to Porto that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated May 13, 2026.
This United Airlines deal was found by Cheapflights users on 5/12. 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.
Wed 10/217:00 am
SEA
- OPO
1 stop18h 45m
United Airlines
Wed 12/1612:30 pm
OPO
- SEA
2 stops20h 03m
United Airlines
Deal found 5/12![United Airlines logo]()
$812
This KLM deal was found by Cheapflights users on 5/8. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/157:15 am
SEA
- OPO
1 stop19h 15m
KLM
Fri 8/145:00 am
OPO
- SEA
1 stop19h 27m
KLM
Deal found 5/8![KLM logo]()
$927
This Delta deal was found by Cheapflights users on 5/9. 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.
Wed 7/81:30 pm
SEA
- OPO
1 stop17h 55m
Delta
Sun 7/2612:25 pm
OPO
- SEA
1 stop34h 25m
Delta
Deal found 5/9![Delta logo]()
$1,024
This United Airlines deal was found by Cheapflights users on 5/8. 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.
Tue 9/157:30 am
SEA
- OPO
1 stop14h 45m
United Airlines
Tue 10/612:15 pm
OPO
- SEA
2 stops40h 09m
United Airlines
Deal found 5/8![United Airlines logo]()
$900
This KLM deal was found by Cheapflights users on 5/12. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/87:15 am
SEA
- OPO
1 stop19h 05m
KLM
Tue 8/2511:35 am
OPO
- SEA
1 stop32h 02m
KLM
Deal found 5/12![KLM logo]()
$948
This United Airlines deal was found by Cheapflights users on 5/9. 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.
Sun 7/127:30 am
SEA
- OPO
1 stop15h 25m
United Airlines
Wed 7/2911:20 am
OPO
- SEA
2 stops30h 20m
United Airlines
Deal found 5/9![United Airlines logo]()
$923
This KLM deal was found by Cheapflights users on 5/10. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/167:15 am
SEA
- OPO
1 stop19h 15m
KLM
Mon 8/104:20 pm
OPO
- SEA
1 stop26h 55m
KLM
Deal found 5/10![KLM logo]()
$1,008
This United Airlines deal was found by Cheapflights users on 5/10. 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.
Sat 7/2511:00 pm
SEA
- OPO
1 stop23h 55m
United Airlines
Thu 8/1311:50 am
OPO
- SEA
2 stops29h 46m
United Airlines
Deal found 5/10![United Airlines logo]()
$923
This United Airlines deal was found by Cheapflights users on 5/9. 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.
Fri 8/215:00 am
SEA
- OPO
2 stops18h 00m
United Airlines
Sun 9/69:00 am
OPO
- SEA
1 stop17h 41m
United Airlines
Deal found 5/9![United Airlines logo]()
$978
This United Airlines deal was found by Cheapflights users on 5/9. 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.
Sun 7/127:30 am
SEA
- OPO
1 stop15h 25m
United Airlines
Sun 7/2612:15 pm
OPO
- SEA
2 stops29h 25m
United Airlines
Deal found 5/9![United Airlines logo]()
$993
Last-minute flights from Seattle to PortoDiscover last-minute flight deals from Seattle to Porto. Data last updated May 13, 2026 and is based on user searches.
Discover last-minute flight deals from Seattle to Porto. Data last updated May 13, 2026 and is based on user searches.
This Lufthansa deal was found by Cheapflights users on 5/12. 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 Lufthansa is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/156:50 pm
SEA
- OPO
1 stop20h 35m
Lufthansa
Tue 6/96:20 am
OPO
- SEA
1 stop18h 39m
Lufthansa
Deal found 5/12![Lufthansa logo]()
$888
This Mytrip deal was found by Cheapflights users on 5/12. 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.
Fri 5/225:50 am
SEA
- OPO
3 stops33h 35m
Multiple Airlines
Fri 5/297:50 pm
OPO
- SEA
3 stops29h 09m
Multiple Airlines
Deal found 5/12![Multiple Airlines logo]()
$941
This Mytrip deal was found by Cheapflights users on 5/8. 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.
Mon 6/13:40 pm
SEA
- OPO
3 stops34h 20m
Multiple Airlines
Wed 6/177:00 am
OPO
- SEA
3 stops34h 40m
Multiple Airlines
Deal found 5/8![Multiple Airlines logo]()
$925
This Mytrip deal was found by Cheapflights users on 5/12. 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 6/116:05 pm
SEA
- OPO
3 stops32h 30m
Multiple Airlines
Thu 6/185:20 pm
OPO
- SEA
2 stops30h 40m
Multiple Airlines
Deal found 5/12![Multiple Airlines logo]()
$923
This Air Canada deal was found by Cheapflights users on 5/13. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 6/273:00 pm
SEA
- OPO
2 stops31h 50m
Air Canada
Thu 10/156:00 am
OPO
- SEA
2 stops40h 22m
Air Canada
Deal found 5/13![Air Canada logo]()
$929
This KAYAK deal was found by Cheapflights users on 5/13. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 6/273:00 pm
SEA
- OPO
2 stops56h 00m
Lufthansa
Thu 10/156:20 am
OPO
- SEA
1 stop18h 39m
Lufthansa
Deal found 5/13![Lufthansa logo]()
$930
This Air Canada deal was found by Cheapflights users on 5/13. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 6/275:45 am
SEA
- OPO
2 stops41h 05m
Air Canada
Fri 10/168:40 am
OPO
- SEA
2 stops20h 24m
Air Canada
Deal found 5/13![Air Canada logo]()
$939
This Gotogate deal was found by Cheapflights users on 5/12. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/307:20 pm
SEA
- OPO
2 stops27h 40m
Multiple Airlines
Tue 9/298:40 am
OPO
- SEA
2 stops17h 52m
Multiple Airlines
Deal found 5/12![Multiple Airlines logo]()
$906
This Lufthansa deal was found by Cheapflights users on 5/13. 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 Lufthansa is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/306:50 pm
SEA
- OPO
1 stop20h 35m
Lufthansa
Fri 10/166:20 am
OPO
- SEA
1 stop18h 39m
Lufthansa
Deal found 5/13![Lufthansa logo]()
$934
One-way flights from Seattle to PortoSearch for one-way flight options from Seattle to Porto. Find affordable one-way fares based on user searches. Data last updated May 13, 2026.
Search for one-way flight options from Seattle to Porto. Find affordable one-way fares based on user searches. Data last updated May 13, 2026.
This Kiwi.com deal was found by Cheapflights users on 5/10. 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 8/117:00 pm
SEA
- OPO
3 stops44h 35m
Multiple Airlines
Deal found 5/10![Multiple Airlines logo]()
$326
This Kiwi.com deal was found by Cheapflights users on 5/9. 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 8/1011:25 pm
SEA
- OPO
2 stops36h 15m
Multiple Airlines
Deal found 5/9![Multiple Airlines logo]()
$327
This Kiwi.com deal was found by Cheapflights users on 5/10. 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 8/811:25 pm
SEA
- OPO
2 stops35h 05m
Multiple Airlines
Deal found 5/10![Multiple Airlines logo]()
$333
This Kiwi.com deal was found by Cheapflights users on 5/8. 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 8/167:00 pm
SEA
- OPO
3 stops44h 30m
Multiple Airlines
Deal found 5/8![Multiple Airlines logo]()
$339
This Kiwi.com deal was found by Cheapflights users on 5/10. 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 9/77:00 pm
SEA
- OPO
3 stops36h 00m
Multiple Airlines
Deal found 5/10![Multiple Airlines logo]()
$355
This Kiwi.com deal was found by Cheapflights users on 5/12. 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 8/193:40 pm
SEA
- OPO
2 stops21h 50m
Multiple Airlines
Deal found 5/12![Multiple Airlines logo]()
$364
This Kiwi.com deal was found by Cheapflights users on 5/12. 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 8/2011:25 pm
SEA
- OPO
2 stops36h 10m
Multiple Airlines
Deal found 5/12![Multiple Airlines logo]()
$368
Find flight deals from Seattle to Porto
Discover tips and strategies to find the most affordable flight options for your journey from Seattle (SEA) to Porto (OPO). 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 May 13, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $621 (Lufthansa) |
One-way from | $326 (Kiwi.com) |
Popular in | December |
Cheapest in | January |
Average price | $950 |
Cheapflights Fare Finder
Customize your flight search to find flights from Seattle to Porto 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 May 13, 2026.
Use the filters below to find and compare flights from Seattle to Porto that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
SeattlePorto
SEA - OPO
SEAOPO
Seattle/Tacoma Intl
Wed 10/21
7:00 am-9:45 am
1 stop18h 45m
Porto
Wed 12/16
12:30 pm-12:33 am
2 stops20h 03m
$812
SeattlePorto
SEA - OPO
SEAOPO
Seattle/Tacoma Intl
Tue 9/15
7:30 am-6:15 am
1 stop14h 45m
Porto
Tue 10/6
12:15 pm-8:24 pm
2 stops40h 09m
$900
SeattlePorto
SEA - OPO
SEAOPO
Seattle/Tacoma Intl
Sun 7/12
7:30 am-6:55 am
1 stop15h 25m
Porto
Wed 7/29
11:20 am-9:40 am
2 stops30h 20m
$923
SeattlePorto
SEA - OPO
SEAOPO
Seattle/Tacoma Intl
Sat 7/25
11:00 pm-6:55 am
1 stop23h 55m
Porto
Thu 8/13
11:50 am-9:36 am
2 stops29h 46m
$923
SeattlePorto
SEA - OPO
SEAOPO
Seattle/Tacoma Intl
Wed 7/15
7:15 am-10:30 am
1 stop19h 15m
Porto
Fri 8/14
5:00 am-4:27 pm
1 stop19h 27m
$927
SeattlePorto
SEA - OPO
SEAOPO
Seattle/Tacoma Intl
Sat 8/8
7:15 am-10:20 am
1 stop19h 05m
Porto
Tue 8/25
11:35 am-11:37 am
1 stop32h 02m
$948
Quickest round-trip
SeattlePorto
SEA - OPO
SEAOPO
Seattle/Tacoma Intl
Fri 8/21
5:00 am-7:00 am
2 stops18h 00m
Porto
Sun 9/6
9:00 am-6:41 pm
1 stop17h 41m
$978
SeattlePorto
SEA - OPO
SEAOPO
Seattle/Tacoma Intl
Sun 7/12
7:30 am-6:55 am
1 stop15h 25m
Porto
Sun 7/26
12:15 pm-9:40 am
2 stops29h 25m
$993
SeattlePorto
SEA - OPO
SEAOPO
Seattle/Tacoma Intl
Thu 7/16
7:15 am-10:30 am
1 stop19h 15m
Porto
Mon 8/10
4:20 pm-11:15 am
1 stop26h 55m
$1,008
SeattlePorto
SEA - OPO
SEAOPO
Seattle/Tacoma Intl
Wed 7/8
1:30 pm-3:25 pm
1 stop17h 55m
Porto
Sun 7/26
12:25 pm-2:50 pm
1 stop34h 25m
$1,024
Showing 1-10 of 21 resultsSorted by cheapest first
Compare providers for flights from Seattle to Porto
Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Seattle to Porto in May.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy- | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars |
- Most accurate provider: When it comes to deals on Seattle-Porto flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Seattle-Porto flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Seattle-Porto flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on Seattle-Porto 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 Seattle-Porto 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 Seattle to Porto
Have a flexible travel schedule? Discover the best time to fly to Porto from Seattle with our price prediction graph.
SEA-OPO
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 Seattle to Porto
How far ahead should I book a flight from Seattle to Porto?
Booking 44 days in advance of your planned departure date is, on average, the best time to get cheap flights from Seattle to Porto. The general trend is that the closer you book to the departure date, the more expensive your flight will be.
What is the cheapest month to book a flight from Seattle to Porto?
Currently, January is the cheapest month in which you can book a flight from Seattle to Porto (average of $498). Flying from Seattle to Porto in December is currently the most expensive (average of $1,451). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.
How much does it cost to fly round-trip from Seattle to Porto?
Reviews of airlines servicing Porto
Get insights into the airlines that provide service to Porto. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Porto. Reviews last updated May 13, 2026.
Peruse reviews from past customers who have flown with Delta,KLM, andUnited Airlines from Seattle to Porto to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Crew
8.5
Boarding
8.1
Comfort
7.8
Entertainment
7.8
Overall
7.9
Food
7.2
Reviews
1 / 20
10.0
ExcellentAnonymous,May 2026
SEA - KOA
Crew
8.5
Boarding
8.1
Comfort
7.8
Entertainment
7.8
Overall
7.9
Food
7.2
Reviews
1 / 20
10.0
ExcellentAnonymous,May 2026
SEA - KOA
Crew
8.5
Boarding
8.1
Comfort
7.8
Entertainment
7.8
Overall
7.9
Food
7.2
Reviews
1 / 20
10.0
ExcellentAnonymous,May 2026
SEA - KOA
Crew
8.5
Boarding
8.1
Comfort
7.8
Entertainment
7.8
Overall
7.9
Food
7.2
Reviews
1 / 20
10.0
ExcellentAnonymous,May 2026
SEA - KOA
Crew
8.5
Boarding
8.1
Comfort
7.8
Entertainment
7.8
Overall
7.9
Food
7.2
Reviews
1 / 20
10.0
ExcellentAnonymous,May 2026
SEA - KOA
Crew
8.5
Boarding
8.1
Comfort
7.8
Entertainment
7.8
Overall
7.9
Food
7.2
Reviews
1 / 20
10.0
ExcellentAnonymous,May 2026
SEA - KOA
Related info for your journey
Find useful and relevant information for your journey from Seattle to Porto. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
Traveling to a place near Porto?
Book flights to Porto if you plan to visit one of these locationsVila Nova de Gaia
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Coimbra
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Top 7 airlines flying from Seattle to Porto
Discover the top 7 airlines that operate flights from Seattle to Porto. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated May 13, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$490 | Average$950 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$503 | Average$855 | FlexibilityNo cancel fee | On-time76% | |
| Cheapest$582 | Average$950 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$651 | Average$909 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$660 | Average$823 | FlexibilityNo cancel fee | On-time67% | |
| Cheapest$665 | Average$758 | FlexibilityNo cancel fee | On-time77% | |
| Cheapest$1,029 | Average$1,301 | FlexibilityNo cancel fee | On-time77% |