What is the cheapest airline that flies from Seattle/Tacoma Intl to Portugal?

Iberia, Delta, and United Airlines are the most popular carriers operating from Seattle/Tacoma Intl to Portugal

What airlines fly to Portugal?

Delta, British Airways and United Airlines are the top three most popular airlines that fly to Portugal from Seattle according to our data. Delta is the first choice among our users, with 37% of people opting to fly with this airline when traveling to Portugal. Keep in mind that there are 12 different airlines that fly to Portugal on a routine basis, so you have a few additional options to choose from.

When did momondo last update prices for flights from Seattle/Tacoma Intl Airport to Portugal?

Prices for flights from Seattle/Tacoma Intl Airport to Portugal were last updated today.

How many operators does momondo search for flights from Seattle/Tacoma Intl Airport to Portugal?

The number of operators available for flights from Seattle/Tacoma Intl Airport to Portugal is 12 as of September 2026.

How old do you have to be to fly from Seattle/Tacoma Intl Airport to Portugal?

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 Portugal.

What documentation or ID do you need to fly to Portugal?

The necessary travel and health documents for your Portugal trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.

$270 Cheap Flights from Seattle to Portugal in 2026/27

Discover deals from 900+ travel sites with momondo.

Find the cheapest flights from Seattle to Portugal

Round-trip

One-way

Last minute

Cheap round-trip flights

Enter your travel dates to find the best prices.

10:56 pm - 9:30 amSEA Seattle/Tacoma Intl-OPO Porto

26h 34m2 stops Chicago O'Hare Intl Newark

12:35 pm - 9:49 pmOPO Porto-SEA Seattle/Tacoma Intl

17h 14m1 stop Newark

$595United Airlines

Sun, Nov 8 - Tue, Nov 24

6:15 am - 9:30 amSEA Seattle/Tacoma Intl-OPO Porto

19h 15m1 stop Newark

12:35 pm - 11:16 amOPO Porto-SEA Seattle/Tacoma Intl

30h 41m1 stop Newark

$595United Airlines

Sun, Nov 8 - Tue, Nov 24

10:43 am - 4:45 pmSEA Seattle/Tacoma Intl-OPO Porto

22h 02m2 stops Chicago O'Hare Intl London Heathrow

8:20 am - 8:21 pmOPO Porto-SEA Seattle/Tacoma Intl

20h 01m2 stops Madrid Barajas Chicago O'Hare Intl

$600British Airways

Sun, Nov 8 - Tue, Nov 24

7:15 am - 8:15 amSEA Seattle/Tacoma Intl-OPO Porto

17h 00m1 stop New York John F Kennedy Intl

10:15 am - 11:00 pmOPO Porto-SEA Seattle/Tacoma Intl

20h 45m1 stop New York John F Kennedy Intl

$604Delta

Wed, Nov 4 - Thu, Nov 19

10:43 am - 4:50 pmSEA Seattle/Tacoma Intl-OPO Porto

22h 07m2 stops Chicago O'Hare Intl London Heathrow

8:20 am - 12:32 amOPO Porto-SEA Seattle/Tacoma Intl

24h 12m2 stops Madrid Barajas Chicago O'Hare Intl

$604British Airways

Wed, Nov 11 - Thu, Dec 3

7:15 am - 8:15 amSEA Seattle/Tacoma Intl-OPO Porto

17h 00m1 stop New York John F Kennedy Intl

10:15 am - 8:19 pmOPO Porto-SEA Seattle/Tacoma Intl

18h 04m1 stop New York John F Kennedy Intl

$604Air France

Wed, Nov 11 - Thu, Dec 3

7:15 am - 8:15 amSEA Seattle/Tacoma Intl-OPO Porto

17h 00m1 stop New York John F Kennedy Intl

10:15 am - 8:19 pmOPO Porto-SEA Seattle/Tacoma Intl

18h 04m1 stop New York John F Kennedy Intl

$605Air France

Wed, Nov 11 - Thu, Dec 3

7:15 am - 8:15 amSEA Seattle/Tacoma Intl-OPO Porto

17h 00m1 stop New York John F Kennedy Intl

11:15 am - 11:47 amOPO Porto-SEA Seattle/Tacoma Intl

32h 32m1 stop Amsterdam Schiphol

$609Delta

Sun, Nov 1 - Tue, Nov 17

2:50 pm - 12:50 pmSEA Seattle/Tacoma Intl-OPO Porto

14h 00m1 stop Munich Franz Josef Strauss

6:15 am - 2:00 pmOPO Porto-SEA Seattle/Tacoma Intl

14h 45m1 stop Munich Franz Josef Strauss

$624Lufthansa

Sun, Feb 7 - Fri, Mar 19

6:50 pm - 11:25 pmSEA Seattle/Tacoma Intl-OPO Porto

20h 35m1 stop Munich Franz Josef Strauss

6:15 am - 1:00 pmOPO Porto-SEA Seattle/Tacoma Intl

14h 45m1 stop Munich Franz Josef Strauss

$627Lufthansa

Tue, Oct 13 - Fri, Nov 6

Cheap last minute flights

Enter your travel dates to find the best prices.

6:45 pm - 5:50 pmSEA Seattle/Tacoma Intl-LIS Lisbon Humberto Delgado

15h 05m1 stop Paris Charles de Gaulle

5:00 am - 11:52 amLIS Lisbon Humberto Delgado-SEA Seattle/Tacoma Intl

14h 52m1 stop Amsterdam Schiphol

$725Delta

Tue, Sep 22 - Tue, Oct 6

7:15 am - 11:15 amSEA Seattle/Tacoma Intl-LIS Lisbon Humberto Delgado

20h 00m2 stops Chicago O'Hare Intl Paris Charles de Gaulle

5:00 am - 11:52 amLIS Lisbon Humberto Delgado-SEA Seattle/Tacoma Intl

14h 52m1 stop Amsterdam Schiphol

$730Delta

Mon, Sep 21 - Wed, Oct 21

1:50 pm - 6:45 pmSEA Seattle/Tacoma Intl-LIS Lisbon Humberto Delgado

20h 55m1 stop Amsterdam Schiphol

7:45 pm - 11:52 amLIS Lisbon Humberto Delgado-SEA Seattle/Tacoma Intl

24h 07m1 stop Amsterdam Schiphol

$737KLM

Mon, Sep 21 - Wed, Oct 21

5:45 pm - 10:50 pmSEA Seattle/Tacoma Intl-LIS Lisbon Humberto Delgado

21h 05m1 stop Amsterdam Schiphol

7:45 pm - 11:52 amLIS Lisbon Humberto Delgado-SEA Seattle/Tacoma Intl

24h 07m1 stop Amsterdam Schiphol

$797KLM

Tue, Sep 22 - Sat, Oct 10

7:10 pm - 9:35 pmSEA Seattle/Tacoma Intl-LIS Lisbon Humberto Delgado

18h 25m1 stop Dublin

10:15 pm - 5:10 pmLIS Lisbon Humberto Delgado-SEA Seattle/Tacoma Intl

26h 55m1 stop Dublin

$940Aer Lingus

Sat, Sep 19 - Wed, Sep 23

6:45 pm - 10:00 pmSEA Seattle/Tacoma Intl-OPO Porto

19h 15m1 stop Paris Charles de Gaulle

7:00 pm - 11:47 amOPO Porto-SEA Seattle/Tacoma Intl

24h 47m1 stop Amsterdam Schiphol

$992Multiple Airlines

Sun, Sep 20 - Sun, Sep 27

11:00 pm - 10:30 amSEA Seattle/Tacoma Intl-LIS Lisbon Humberto Delgado

27h 30m2 stops Chicago O'Hare Intl Washington, D.C. Dulles Intl

12:20 pm - 9:38 amLIS Lisbon Humberto Delgado-SEA Seattle/Tacoma Intl

29h 18m2 stops Washington, D.C. Dulles Intl Chicago O'Hare Intl

$994United Airlines

Tue, Sep 22 - Sat, Oct 10

7:11 am - 10:30 amSEA Seattle/Tacoma Intl-LIS Lisbon Humberto Delgado

19h 19m2 stops San Francisco Washington, D.C. Dulles Intl

12:20 pm - 9:38 amLIS Lisbon Humberto Delgado-SEA Seattle/Tacoma Intl

29h 18m2 stops Washington, D.C. Dulles Intl Chicago O'Hare Intl

$994United Airlines

Tue, Sep 22 - Sat, Oct 10

8:20 pm - 11:00 pmSEA Seattle/Tacoma Intl-LIS Lisbon Humberto Delgado

18h 40m1 stop London Heathrow

10:40 am - 4:50 pmLIS Lisbon Humberto Delgado-SEA Seattle/Tacoma Intl

14h 10m1 stop London Heathrow

$1,021British Airways

Tue, Sep 22 - Tue, Dec 22

6:18 am - 9:05 amSEA Seattle/Tacoma Intl-LIS Lisbon Humberto Delgado

18h 47m2 stops Chicago O'Hare Intl Philadelphia

11:05 am - 10:11 pmLIS Lisbon Humberto Delgado-SEA Seattle/Tacoma Intl

19h 06m1 stop Philadelphia

$1,048American Airlines

Tue, Sep 22 - Tue, Dec 22

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Air Canada flights from Seattle to Portugal

Our best Air Canada deals on Seattle to Portugal flight tickets

Air Canada

Jan 9

SEA8:40 amSeattle/Tacoma Intl

16h 00m

2 stops

LIS8:40 amLisbon Humberto Delgado

Feb 11

LIS11:20 amLisbon Humberto Delgado

30h 12m

2 stops

SEA9:32 amSeattle/Tacoma Intl

$739

Air Canada

Oct 18

SEA3:00 pmSeattle/Tacoma Intl

34h 20m

2 stops

LIS9:20 amLisbon Humberto Delgado

Oct 27

LIS6:05 amLisbon Humberto Delgado

19h 17m

2 stops

SEA6:22 pmSeattle/Tacoma Intl

$750

Air Canada

Jan 9

SEA7:05 pmSeattle/Tacoma Intl

30h 15m

2 stops

LIS9:20 amLisbon Humberto Delgado

Feb 10

LIS5:00 amLisbon Humberto Delgado

17h 37m

2 stops

SEA2:37 pmSeattle/Tacoma Intl

$754

SWISS flights from Seattle to Portugal

Our best SWISS deals on Seattle to Portugal flight tickets

SWISS

Feb 9

SEA3:30 pmSeattle/Tacoma Intl

35h 45m

2 stops

OPO11:15 amPorto

Mar 23

OPO12:05 pmPorto

43h 09m

2 stops

SEA12:14 amSeattle/Tacoma Intl

$638

SWISS

Jan 8

SEA3:30 pmSeattle/Tacoma Intl

39h 05m

2 stops

LIS2:35 pmLisbon Humberto Delgado

Feb 13

LIS12:35 pmLisbon Humberto Delgado

42h 46m

2 stops

SEA11:21 pmSeattle/Tacoma Intl

$746

SWISS

Oct 14

SEA3:18 pmSeattle/Tacoma Intl

24h 07m

2 stops

LIS11:25 pmLisbon Humberto Delgado

Nov 2

LIS3:35 pmLisbon Humberto Delgado

39h 32m

2 stops

SEA11:07 pmSeattle/Tacoma Intl

$766

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

SeattlePorto

SEA Seattle/Tacoma Intl - OPO Porto

SEAOPO

Seattle/Tacoma Intl

Sun 11/8

10:56 pm-9:30 am

2 stops26h 34m

Porto

Tue 11/24

12:35 pm-9:49 pm

1 stop17h 14m

$595

SeattlePorto

SEA Seattle/Tacoma Intl - OPO Porto

SEAOPO

Seattle/Tacoma Intl

Sun 11/8

6:15 am-9:30 am

1 stop19h 15m

Porto

Tue 11/24

12:35 pm-11:16 am

1 stop30h 41m

$595

SeattlePorto

SEA Seattle/Tacoma Intl - OPO Porto

SEAOPO

Seattle/Tacoma Intl

Sun 11/8

10:43 am-4:45 pm

2 stops22h 02m

Porto

Tue 11/24

8:20 am-8:21 pm

2 stops20h 01m

$600

SeattlePorto

SEA Seattle/Tacoma Intl - OPO Porto

SEAOPO

Seattle/Tacoma Intl

Wed 11/4

7:15 am-8:15 am

1 stop17h 00m

Porto

Thu 11/19

10:15 am-11:00 pm

1 stop20h 45m

$604

SeattlePorto

SEA Seattle/Tacoma Intl - OPO Porto

SEAOPO

Seattle/Tacoma Intl

Wed 11/11

10:43 am-4:50 pm

2 stops22h 07m

Porto

Thu 12/3

8:20 am-12:32 am

2 stops24h 12m

$604

SeattlePorto

SEA Seattle/Tacoma Intl - OPO Porto

SEAOPO

Seattle/Tacoma Intl

Wed 11/11

7:15 am-8:15 am

1 stop17h 00m

Porto

Thu 12/3

10:15 am-8:19 pm

1 stop18h 04m

$604

SeattlePorto

SEA Seattle/Tacoma Intl - OPO Porto

SEAOPO

Seattle/Tacoma Intl

Wed 11/11

7:15 am-8:15 am

1 stop17h 00m

Porto

Thu 12/3

10:15 am-8:19 pm

1 stop18h 04m

$605

SeattlePorto

SEA Seattle/Tacoma Intl - OPO Porto

SEAOPO

Seattle/Tacoma Intl

Sun 11/1

7:15 am-8:15 am

1 stop17h 00m

Porto

Tue 11/17

11:15 am-11:47 am

1 stop32h 32m

$609

Quickest round-trip

SeattlePorto

SEA Seattle/Tacoma Intl - OPO Porto

SEAOPO

Seattle/Tacoma Intl

Sun 2/7

2:50 pm-12:50 pm

1 stop14h 00m

Porto

Fri 3/19

6:15 am-2:00 pm

1 stop14h 45m

$624

SeattlePorto

SEA Seattle/Tacoma Intl - OPO Porto

SEAOPO

Seattle/Tacoma Intl

Tue 10/13

6:50 pm-11:25 pm

1 stop20h 35m

Porto

Fri 11/6

6:15 am-1:00 pm

1 stop14h 45m

$627

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first

How to get the cheapest flight ticket from Seattle to Portugal

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

Prices

Airlines

What is the cheapest month to fly to Portugal?

The cheapest month to fly to Portugal from Seattle is in January. Flight prices, which tend to average around $470, are often lower during this time because this is during the off-season. If you aren’t able to travel during the month of January, then book flights to Portugal from Seattle during February instead. Flights to Portugal in February, while not as cheap as those in January, still average around $580.

How far in advance should I book a flight from Seattle to Portugal?

You are more likely to see cheaper flights to Portugal from Seattle when booking weeks ahead of your departure date. In general, you can expect to find flights to Portugal for around $855 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Portugal from Seattle for as low as $780 on momondo.

Can stopping save me money on Seattle to Portugal flights?

You could potentially save up to 2% on your flight if you consider stops on a Seattle to Portugal flight.

Cheap Seattle to Portugal flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Seattle to Portugal

Best Price Found	$270
Fastest flight time	13h 10m
Direct flights	None

The best one-way flight to Portugal from Seattle in the past 72 hours is $270. The best round-trip flight deal from Seattle to Portugal found on momondo in the last 72 hours is $595.

The fastest flight from Seattle to Portugal takes 13h 10m

There are no direct flights from Seattle to Portugal. There are no popular flight routes from Seattle to Portugal.

Search flight deals

Frequently asked questions about flying from Seattle to Portugal

When did momondo last update prices for flights from Seattle/Tacoma Intl Airport to Portugal?
Prices for flights from Seattle/Tacoma Intl Airport to Portugal were last updated today.
How many operators does momondo search for flights from Seattle/Tacoma Intl Airport to Portugal?
The number of operators available for flights from Seattle/Tacoma Intl Airport to Portugal is 12 as of September 2026.
How old do you have to be to fly from Seattle/Tacoma Intl Airport to Portugal?
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 Portugal.
What documentation or ID do you need to fly to Portugal?
The necessary travel and health documents for your Portugal trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.

Best airlines flying from Seattle to Portugal

Compare and see reviews for airlines that fly from Seattle to Portugal with momondo

Airline	Rating	Free Cancellation	Price
Icelandair	PriceFrom $345	Free Cancellation	Rating 6.9 745 reviews	Search Icelandair flights
Lufthansa	PriceFrom $471	Free Cancellation	Rating 6.8 8,231 reviews	Search Lufthansa flights
KLM	PriceFrom $481	Free Cancellation	Rating 7.8 1,578 reviews	Search KLM flights
British Airways	PriceFrom $482	Free Cancellation	Rating 6.7 8,229 reviews	Search British Airways flights
United Airlines	PriceFrom $482	Free Cancellation	Rating 7.4 10,214 reviews	Search United Airlines flights
American Airlines	PriceFrom $497	Free Cancellation	Rating 7.1 12,076 reviews	Search American Airlines flights
Air France	PriceFrom $504	Free Cancellation	Rating 7.5 1,650 reviews	Search Air France flights
Delta	PriceFrom $554	Free Cancellation	Rating 7.8 8,581 reviews	Search Delta flights
Scandinavian Airlines	PriceFrom $567	Free Cancellation	Rating 7.4 1,984 reviews	Search Scandinavian Airlines flights
Air Canada	PriceFrom $660	Free Cancellation	Rating 7.1 11,644 reviews	Search Air Canada flights

Why use momondo?

Why should I use momondo to find a flight deal from Seattle to Portugal?

It is quick and easy to find Seattle to Portugal flights on momondo. We search and return numerous flight options from various airlines and agents. You can then use our filters to narrow your search until you have found the most convenient flight to Portugal that suits you.

Can I find flights from Seattle to Portugal with flexible booking policies on momondo?

All flight searches from Seattle to Portugal on momondo can be filtered to show those which offer flexible booking policies.

How can momondo help me find flights from Seattle to Portugal?

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 Portugal.

I’m not ready to book a flight from Seattle to Portugal right now. Can momondo alert me if prices change?

If you are simply researching potential flights to Portugal, momondo offers a useful price alert feature which will track prices for flights to Portugal from Seattle and alert you when they change.

An easier way to manage your Portugal 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.

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Find better results for your trip to Portugal

Popular cities

Other flights from Seattle

Other flights to Portugal

Airlines

Cabin classes

Complete your trip

Feeling lucky

Popular cities in Portugal

Flights to Lisbonfrom $469

Flights to Portofrom $470

Flights to Funchalfrom $570

Flights to Farofrom $509

Flights to Ponta Delgadafrom $560

Flights to Lajesfrom $569

Flights to Hortafrom $570

Flights to Pico Islandfrom $570

Flights to Porto Santofrom $756

Flights to Velasfrom $593

Cheap flights from Seattle to Portugal from $270

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 Portugal departing on 10/11. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

Find the cheapest flights from Seattle to Portugal

Cheap round-trip flights

Cheap one-way flights

Cheap last minute flights

Big names and deals

Big names and deals

Filter for what you want

Filter for what you want

Trusted and free

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Price Alerts

Price Alerts

Air Canada flights from Seattle to Portugal

Our best Air Canada deals on Seattle to Portugal flight tickets

SWISS flights from Seattle to Portugal

Our best SWISS deals on Seattle to Portugal flight tickets

momondo Fare Finder

Use the filters below to find and compare flights from Seattle to Portugal that are best for you.

See travel insights to Portugal from

How to get the cheapest flight ticket from Seattle to Portugal

What is the cheapest month to fly to Portugal?

How far in advance should I book a flight from Seattle to Portugal?

Can stopping save me money on Seattle to Portugal flights?

What is the cheapest airline that flies from Seattle/Tacoma Intl to Portugal?

What airlines fly to Portugal?

Cheap Seattle to Portugal flight deals and tips

Best Price Found

Fastest flight time

Direct flights

Frequently asked questions about flying from Seattle to Portugal

Best airlines flying from Seattle to Portugal

Compare and see reviews for airlines that fly from Seattle to Portugal with momondo

Why use momondo?

An easier way to manage your Portugal 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.

Get notified when prices go down

Daily price changes in your inbox - only with Price Alerts.

Find better results for your trip to Portugal

Popular cities in Portugal

Popular flights according to clicks in the last 7 days on momondo

Seattle flight routes

According to popular flight searches on momondo this year

Portugal flight routes

According to popular flight searches on momondo this year

Fly your favorite airline to Portugal

Airlines are sorted and displayed according to clicks in the past 7 days on momondo

Cabin classes currently available on flights to Portugal

List of cabin classes available on flights landing in Portugal. Availability may vary depending on flight origin and airline.

Complete your trip to Portugal

Explore popular destinations other users love

According to popular flight searches on momondo this year