Latest deals
Insights
When to book
FAQs
Reviews
Price Alerts

Cheap flights from Seattle to Porto from $257

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 8/8. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
1 adult
0 bags

Discover deals from 900+ travel sites with momondo.

Save money when you book flights with momondo

Big names and deals

Big names and deals

Search 100s of travel sites to compare prices.

Filter for what you want

Filter for what you want

Free Wi-Fi? Stopover? Instantly customize your results.

Trusted and free

Trusted and free

We’re completely free to use - no hidden charges or fees.

Price Alerts

Price Alerts

Not ready to book? to track prices.
Search flight deals

Find the cheapest flights from Seattle to Porto

Cheap round-trip flights

Enter your travel dates to find the best prices.
Delta Logo
6:40 pm - 10:00 pm
SEA
-
OPO
19h 20m
1 stop
Delta Logo
5:00 am - 4:30 pm
OPO
-
SEA
19h 30m
1 stop
$478Delta
Mon, Apr 13 - Thu, Apr 23
Multiple Airlines Logo
6:40 pm - 10:00 pm
SEA
-
OPO
19h 20m
1 stop
Multiple Airlines Logo
4:20 pm - 11:45 am
OPO
-
SEA
27h 25m
1 stop
$479Multiple Airlines
Mon, Apr 13 - Wed, Apr 22
Lufthansa Logo
2:10 pm - 10:50 pm
SEA
-
OPO
24h 40m
1 stop
Lufthansa Logo
6:20 am - 4:59 pm
OPO
-
SEA
18h 39m
1 stop
$482Lufthansa
Mon, Apr 13 - Wed, Apr 22
Delta Logo
1:45 pm - 10:05 pm
SEA
-
OPO
24h 20m
2 stops
Delta Logo
5:00 am - 4:30 pm
OPO
-
SEA
19h 30m
1 stop
$483Delta
Tue, Apr 14 - Thu, Apr 23
Delta Logo
6:40 pm - 10:00 pm
SEA
-
OPO
19h 20m
1 stop
Delta Logo
5:00 am - 9:49 pm
OPO
-
SEA
24h 49m
2 stops
$488Delta
Mon, Apr 13 - Wed, Apr 22
Delta Logo
6:40 pm - 10:00 pm
SEA
-
OPO
19h 20m
1 stop
Delta Logo
5:00 am - 8:43 pm
OPO
-
SEA
23h 43m
2 stops
$489Delta
Mon, Apr 13 - Fri, Apr 24
Delta Logo
1:45 pm - 10:05 pm
SEA
-
OPO
24h 20m
2 stops
Delta Logo
5:00 am - 9:50 pm
OPO
-
SEA
24h 50m
2 stops
$493Delta
Tue, Apr 14 - Thu, Apr 23
Lufthansa Logo
2:10 pm - 10:50 pm
SEA
-
OPO
24h 40m
1 stop
Lufthansa Logo
6:20 am - 4:59 pm
OPO
-
SEA
18h 39m
1 stop
$495Lufthansa
Tue, Apr 14 - Wed, Apr 22
Delta Logo
11:59 pm - 10:55 am
SEA
-
OPO
26h 56m
2 stops
Delta Logo
5:00 am - 9:50 pm
OPO
-
SEA
24h 50m
2 stops
$498Delta
Mon, Apr 13 - Thu, Apr 23
Delta Logo
6:00 am - 6:10 pm
SEA
-
OPO
28h 10m
2 stops
Delta Logo
5:00 am - 8:43 pm
OPO
-
SEA
23h 43m
2 stops
$499Delta
Sun, Apr 12 - Fri, Apr 24

United Airlines flights from Seattle to Porto

Our best United Airlines deals on Seattle to Porto flight tickets
United Airlines
Apr 12
SEA11:59 pmSeattle/Tacoma Intl
27h 16m
2 stops
OPO11:15 amPorto
Apr 22
OPO6:00 amPorto
23h 06m
2 stops
SEA9:06 pmSeattle/Tacoma Intl
$508
United Airlines
Mar 11
SEA8:00 amSeattle/Tacoma Intl
24h 25m
2 stops
OPO3:25 pmPorto
Mar 18
OPO6:00 amPorto
25h 59m
2 stops
SEA12:59 amSeattle/Tacoma Intl
$512
United Airlines
Apr 12
SEA11:59 pmSeattle/Tacoma Intl
27h 16m
2 stops
OPO11:15 amPorto
Apr 22
OPO12:00 pmPorto
32h 20m
1 stop
SEA12:20 pmSeattle/Tacoma Intl
$518

Iberia flights from Seattle to Porto

Our best Iberia deals on Seattle to Porto flight tickets
Iberia
Feb 19
SEA10:22 amSeattle/Tacoma Intl
21h 38m
2 stops
OPO4:00 pmPorto
Feb 23
OPO9:55 pmPorto
21h 35m
2 stops
SEA11:30 amSeattle/Tacoma Intl
$1,036
Iberia
Feb 19
SEA6:44 amSeattle/Tacoma Intl
16h 56m
2 stops
OPO7:40 amPorto
Feb 23
OPO9:55 pmPorto
27h 00m
2 stops
SEA4:55 pmSeattle/Tacoma Intl
$1,101

momondo 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, momondo users made 832,500 searches. Data last updated February 12, 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

Price

SeattlePorto

SEA - OPO

SEAOPO

Seattle/Tacoma Intl

Mon 4/13

6:40 pm-10:00 pm

1 stop19h 20m

Porto

Thu 4/23

5:00 am-4:30 pm

1 stop19h 30m

$478

SeattlePorto

SEA - OPO

SEAOPO

Seattle/Tacoma Intl

Mon 4/13

6:40 pm-10:00 pm

1 stop19h 20m

Porto

Wed 4/22

4:20 pm-11:45 am

1 stop27h 25m

$479

SeattlePorto

SEA - OPO

SEAOPO

Seattle/Tacoma Intl

Mon 4/13

2:10 pm-10:50 pm

1 stop24h 40m

Porto

Wed 4/22

6:20 am-4:59 pm

1 stop18h 39m

$482

SeattlePorto

SEA - OPO

SEAOPO

Seattle/Tacoma Intl

Tue 4/14

1:45 pm-10:05 pm

2 stops24h 20m

Porto

Thu 4/23

5:00 am-4:30 pm

1 stop19h 30m

$483

SeattlePorto

SEA - OPO

SEAOPO

Seattle/Tacoma Intl

Mon 4/13

6:40 pm-10:00 pm

1 stop19h 20m

Porto

Wed 4/22

5:00 am-9:49 pm

2 stops24h 49m

$488

SeattlePorto

SEA - OPO

SEAOPO

Seattle/Tacoma Intl

Mon 4/13

6:40 pm-10:00 pm

1 stop19h 20m

Porto

Fri 4/24

5:00 am-8:43 pm

2 stops23h 43m

$489

SeattlePorto

SEA - OPO

SEAOPO

Seattle/Tacoma Intl

Tue 4/14

1:45 pm-10:05 pm

2 stops24h 20m

Porto

Thu 4/23

5:00 am-9:50 pm

2 stops24h 50m

$493

SeattlePorto

SEA - OPO

SEAOPO

Seattle/Tacoma Intl

Tue 4/14

2:10 pm-10:50 pm

1 stop24h 40m

Porto

Wed 4/22

6:20 am-4:59 pm

1 stop18h 39m

$495

SeattlePorto

SEA - OPO

SEAOPO

Seattle/Tacoma Intl

Mon 4/13

11:59 pm-10:55 am

2 stops26h 56m

Porto

Thu 4/23

5:00 am-9:50 pm

2 stops24h 50m

$498

SeattlePorto

SEA - OPO

SEAOPO

Seattle/Tacoma Intl

Sun 4/12

6:00 am-6:10 pm

2 stops28h 10m

Porto

Fri 4/24

5:00 am-8:43 pm

2 stops23h 43m

$499

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first
1
2

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 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 $662.

How far in advance should I book a flight 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 $898 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 $739 on momondo.

Can stopping save me money on Seattle to Porto flights?

You could potentially save up to 24% on your flight if you consider stops on a Seattle to Porto flight.

How have Seattle to Porto flight prices changed over time?

When to book flights from Seattle to Porto

Are you open to changing your travel dates? Check out the ideal times to fly from Seattle to Porto according to our flight data. Find out which month and days have the cheapest flights.
Estimated round-trip price

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

Fastest flight time

17h 30m

Direct flights

None
The fastest flight from Seattle to Porto takes 17h 30m
There are no direct flights from Seattle to Porto. There are no popular flight routes from Seattle to Porto.
Search flight deals

  • 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 30m 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?

  • 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?

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
KLMPriceFrom $490Free CancellationRating
7.7
1,451 reviews
Search KLM flights
LufthansaPriceFrom $503Free CancellationRating
6.8
7,780 reviews
Search Lufthansa flights
DeltaPriceFrom $580Free CancellationRating
7.9
8,181 reviews
Search Delta flights
United AirlinesPriceFrom $664Free CancellationRating
7.4
9,279 reviews
Search United Airlines flights

Traveling to a place near Porto?

Book flights to Porto if you plan to visit one of these locations
Vila Nova de Gaia
Coimbra
Matosinhos
Braga
Aveiro
Esposende
Lamego
Guimarães
Pinhao
Chaves
Espinho
Arcos de Valdevez
Viseu
Ponte de Lima
Curia
Penafiel
Mesao Frio
Mira
Baiao

Why 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.

An easier way to manage your Porto trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.
Start using Trips
Find my bookings

Get notified when prices go down

Daily price changes in your inbox - only with Price Alerts.
1 adult
Sat 3/14
Sat 3/21
By creating a price alert you accept our terms of use and privacy policy.

Find better results for your trip to Portugal