Cheap flights from Seattle to Porto from $292
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Seattle to Porto departing on 10/18. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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KLM flights from Seattle to Porto
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Fly from
Fly to
Route
Depart
Return
SeattlePorto
SEA Seattle/Tacoma Intl - OPO Porto
SEAOPO
Seattle/Tacoma Intl
Thu 11/5
4:05 pm-10:00 pm
1 stop21h 55m
Porto
Thu 11/12
10:15 am-11:00 pm
1 stop20h 45m
SeattlePorto
SEA Seattle/Tacoma Intl - OPO Porto
SEAOPO
Seattle/Tacoma Intl
Thu 11/5
4:05 pm-10:00 pm
1 stop21h 55m
Porto
Thu 11/12
5:00 am-4:53 pm
2 stops19h 53m
SeattlePorto
SEA Seattle/Tacoma Intl - OPO Porto
SEAOPO
Seattle/Tacoma Intl
Tue 1/5
4:05 pm-10:00 pm
1 stop21h 55m
Porto
Thu 2/4
11:15 am-11:47 am
1 stop32h 32m
SeattlePorto
SEA Seattle/Tacoma Intl - OPO Porto
SEAOPO
Seattle/Tacoma Intl
Tue 1/5
4:05 pm-10:00 pm
1 stop21h 55m
Porto
Mon 2/8
11:15 am-11:47 am
1 stop32h 32m
SeattlePorto
SEA Seattle/Tacoma Intl - OPO Porto
SEAOPO
Seattle/Tacoma Intl
Tue 2/2
4:05 pm-10:00 pm
1 stop21h 55m
Porto
Wed 3/3
5:00 am-11:35 am
1 stop14h 35m
SeattlePorto
SEA Seattle/Tacoma Intl - OPO Porto
SEAOPO
Seattle/Tacoma Intl
Mon 3/1
1:50 pm-3:30 pm
1 stop17h 40m
Porto
Mon 3/8
7:20 pm-11:21 pm
2 stops36h 01m
SeattlePorto
SEA Seattle/Tacoma Intl - OPO Porto
SEAOPO
Seattle/Tacoma Intl
Wed 2/3
2:50 pm-11:55 pm
1 stop25h 05m
Porto
Fri 3/5
6:15 am-1:00 pm
1 stop14h 45m
SeattlePorto
SEA Seattle/Tacoma Intl - OPO Porto
SEAOPO
Seattle/Tacoma Intl
Sun 1/31
7:45 am-11:15 am
2 stops43h 30m
Porto
Thu 3/4
6:00 am-6:20 pm
2 stops20h 20m
SeattlePorto
SEA Seattle/Tacoma Intl - OPO Porto
SEAOPO
Seattle/Tacoma Intl
Mon 2/1
7:45 am-11:15 am
2 stops43h 30m
Porto
Wed 3/3
6:00 am-9:30 am
2 stops35h 30m
SeattlePorto
SEA Seattle/Tacoma Intl - OPO Porto
SEAOPO
Seattle/Tacoma Intl
Wed 2/3
7:00 am-11:55 pm
2 stops32h 55m
Porto
Fri 3/5
6:15 am-1:00 pm
1 stop14h 45m
See travel insights to Porto from
How to get the cheapest flight ticket from Seattle to Porto
Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip
What is the typical price of a round-trip flight between Seattle and Porto?
Prices are currently low for flights on this route.
Typical prices usually range from $758 to $905.The lowest price recently found on this route was $668.
What is the cheapest month to fly to Porto?
The month of January is, on average, the cheapest month to fly to Porto from Seattle, with most prices found around $498. If you aren’t able to travel during the month of January, then book flights to Porto from Seattle during March instead. Flights to Porto in March, while not as cheap as those in January, still average around $680.
How far in advance should I book a flight from Seattle to Porto?
You are more likely to see cheaper flights to Porto from Seattle when booking weeks ahead of your departure date. In general, you can expect to find flights to Porto for around $897 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Porto from Seattle for as low as $745 on momondo.
Can stopping save me money on Seattle to Porto flights?
You could potentially save up to 5% on your flight if you consider stops on a Seattle to Porto flight.
How have Seattle to Porto flight prices changed over time?
What is the cheapest airline that flies from Seattle/Tacoma Intl to Porto?
Lufthansa and United Airlines are the most popular carriers operating from Seattle/Tacoma Intl to Porto
What airlines fly to Porto?
Delta, KLM and Lufthansa are the top three most popular airlines that fly to Porto from Seattle according to our data. Delta is the first choice among our users, with 49% of people opting to fly with this airline when traveling to Porto. Keep in mind that there are 6 different airlines that fly to Porto on a routine basis, so you have a few additional options to choose from.
Which airport is the most popular layover for flights between Seattle and Porto?
Amsterdam (AMS) was the most common stop: 75% of momondo users choosing 1-stop flights on this route connected there.
Which layover airport offers the lowest fares from Seattle to Porto?
Flights via New York (JFK) offer the lowest average round-trip price of $971.
Which layover airport has the shortest travel time from Seattle to Porto?
Flights connecting via New York (JFK) have the shortest average one-way travel time: 14h 58m.
Which layover airport has the shortest connection time from Seattle to Porto?
Amsterdam (AMS) has the shortest average layover time for this route: 2h 32m.
When to book flights from Seattle to Porto
Cheap Seattle to Porto (SEA to OPO) flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from Seattle to Porto
Frequently asked questions about flying from Seattle to Porto
How far is Seattle/Tacoma Intl to Porto by plane?
Seattle/Tacoma Intl and Porto are 5083.1 mi apart from one another. Typically, this will take 17h 00m by plane in normal conditions.
When did momondo last update prices for flights from Seattle/Tacoma Intl Airport to Porto Airport?
Prices for flights from Seattle/Tacoma Intl Airport to Porto Airport are refreshed on a daily basis.
How many operators does momondo search for flights from Seattle/Tacoma Intl Airport to Porto Airport?
As of October 2026, there are 6 operators available to choose from for flights from Seattle/Tacoma Intl Airport to Porto Airport.
How old do you have to be to fly from Seattle/Tacoma Intl Airport to Porto Airport?
The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Seattle/Tacoma Intl Airport to Porto Airport.
What documentation or ID do you need to fly to Porto Airport?
The travel and health documents you'll need for your trip to Porto Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Porto Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.
What is the most popular airline from Seattle to Porto?
Based on momondo bookings for flights between Seattle and Porto, the leading airline is Delta, making up 44% of the total bookings. Other popular airlines include KLM with 22%, Lufthansa with 14%, and United Airlines with 9%.
Best airlines flying from Seattle to Porto
Compare and see reviews for airlines that fly from Seattle to Porto with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $490 | Free Cancellation | Rating 7.8 1,580 reviews | |||
| PriceFrom $503 | Free Cancellation | Rating 6.8 8,271 reviews | |||
| PriceFrom $630 | Free Cancellation | Rating 7.8 8,646 reviews | |||
| PriceFrom $660 | Free Cancellation | Rating 7.1 11,749 reviews | |||
| PriceFrom $691 | Free Cancellation | Rating 7.4 10,322 reviews | |||
| PriceFrom $795 | Free Cancellation | Rating 7.5 1,650 reviews |
Traveling to a place near Porto?
Book flights to Porto if you plan to visit one of these locationsWhy use momondo?
Why should I use momondo to find a flight deal from Seattle to Porto?
To find the flight that best suits your needs, momondo gathers a range of flights from a large pool of different airlines and agents; you can then use our insights and filters to find and book the right flight to Porto from Seattle.
Can I find flights from Seattle to Porto with flexible booking policies on momondo?
Yes. All flights to Porto from Seattle on momondo can be compared and filtered by various policies on offer, including flexible booking.
How can momondo help me find flights from Seattle to Porto?
momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from Seattle to Porto.
I’m not ready to book a flight from Seattle to Porto right now. Can momondo alert me if prices change?
If you are simply researching potential flights to Porto, momondo offers a useful price alert feature which will track prices for flights to Porto from Seattle and alert you when they change.