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

KLM, Icelandair, and British Airways are the most popular carriers operating from Seattle/Tacoma Intl to Portugal

What airlines fly to Portugal?

Delta, British Airways and Lufthansa 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 36% 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 August 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.

$273 Cheap Flights from Seattle to Portugal in 2026

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.

2:35 pm - 12:50 pmSEA Seattle/Tacoma Intl-LIS Lisbon Humberto Delgado

14h 15m1 stop Reykjavik Keflavik Intl

2:00 pm - 5:00 pmLIS Lisbon Humberto Delgado-SEA Seattle/Tacoma Intl

35h 00m1 stop Reykjavik Keflavik Intl

$702Icelandair

Sat, Dec 5 - Sun, Dec 13

2:35 pm - 12:50 pmSEA Seattle/Tacoma Intl-LIS Lisbon Humberto Delgado

14h 15m1 stop Reykjavik Keflavik Intl

2:00 pm - 5:00 pmLIS Lisbon Humberto Delgado-SEA Seattle/Tacoma Intl

35h 00m1 stop Reykjavik Keflavik Intl

$710Icelandair

Sat, Dec 5 - Sun, Dec 13

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

20h 35m1 stop Munich Franz Josef Strauss

1:45 pm - 1:00 pmOPO Porto-SEA Seattle/Tacoma Intl

31h 15m1 stop Munich Franz Josef Strauss

$715Lufthansa

Sun, Oct 18 - Tue, Nov 3

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

14h 00m1 stop Munich Franz Josef Strauss

6:00 am - 6:20 pmOPO Porto-SEA Seattle/Tacoma Intl

20h 20m2 stops Frankfurt am Main Vancouver Intl

$717Multiple Airlines

Wed, Jan 6 - Tue, Mar 2

10:10 am - 9:20 amSEA Seattle/Tacoma Intl-LIS Lisbon Humberto Delgado

15h 10m2 stops Vancouver Intl Montreal Pierre Elliott Trudeau Intl

5:00 am - 6:22 pmLIS Lisbon Humberto Delgado-SEA Seattle/Tacoma Intl

21h 22m2 stops Frankfurt am Main Vancouver Intl

$720Multiple Airlines

Wed, Jan 27 - Wed, Feb 24

2:50 pm - 1:30 pmSEA Seattle/Tacoma Intl-LIS Lisbon Humberto Delgado

14h 40m1 stop Munich Franz Josef Strauss

6:00 am - 1:00 pmLIS Lisbon Humberto Delgado-SEA Seattle/Tacoma Intl

15h 00m1 stop Munich Franz Josef Strauss

$727Lufthansa

Sun, Nov 1 - Fri, Nov 20

8:00 am - 11:05 amSEA Seattle/Tacoma Intl-LIS Lisbon Humberto Delgado

19h 05m1 stop Toronto Pearson Intl

6:05 am - 6:22 pmLIS Lisbon Humberto Delgado-SEA Seattle/Tacoma Intl

20h 17m2 stops Munich Franz Josef Strauss Vancouver Intl

$728Air Canada

Sun, Oct 18 - Tue, Nov 3

3:25 pm - 9:55 pmSEA Seattle/Tacoma Intl-OPO Porto

22h 30m1 stop Paris Charles de Gaulle

11:15 am - 11:50 amOPO Porto-SEA Seattle/Tacoma Intl

32h 35m1 stop Amsterdam Schiphol

$743Delta

Sun, Nov 29 - Wed, Dec 9

3:25 pm - 9:55 pmSEA Seattle/Tacoma Intl-OPO Porto

22h 30m1 stop Paris Charles de Gaulle

11:15 am - 11:50 amOPO Porto-SEA Seattle/Tacoma Intl

32h 35m1 stop Amsterdam Schiphol

$743Delta

Sun, Nov 29 - Mon, Dec 7

7:05 pm - 10:40 amSEA Seattle/Tacoma Intl-LIS Lisbon Humberto Delgado

31h 35m2 stops Vancouver Intl Montreal Pierre Elliott Trudeau Intl

5:00 am - 6:22 pmLIS Lisbon Humberto Delgado-SEA Seattle/Tacoma Intl

21h 22m2 stops Frankfurt am Main Vancouver Intl

$743Air Canada

Sun, Nov 22 - Thu, Dec 3

Cheap last minute flights

Enter your travel dates to find the best prices.

7:10 pm - 9:55 pmSEA Seattle/Tacoma Intl-LIS Lisbon Humberto Delgado

18h 45m1 stop Dublin

6:15 am - 9:40 amLIS Lisbon Humberto Delgado-SEA Seattle/Tacoma Intl

35h 25m2 stops Halifax Intl Calgary

$906Multiple Airlines

Sat, Sep 5 - Tue, Sep 15

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

$1,036Aer Lingus

Sat, Sep 5 - Tue, Sep 8

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

19h 15m1 stop Paris Charles de Gaulle

5:00 am - 11:47 amOPO Porto-SEA Seattle/Tacoma Intl

14h 47m1 stop Amsterdam Schiphol

$1,104Delta

Wed, Sep 2 - Sat, Sep 12

9:53 am - 3:25 pmSEA Seattle/Tacoma Intl-OPO Porto

21h 32m2 stops Detroit Metropolitan Wayne County Paris Charles de Gaulle

5:00 am - 11:47 amOPO Porto-SEA Seattle/Tacoma Intl

14h 47m1 stop Amsterdam Schiphol

$1,108Delta

Wed, Sep 2 - Sat, Sep 12

5:45 pm - 10:15 pmSEA Seattle/Tacoma Intl-OPO Porto

20h 30m1 stop Amsterdam Schiphol

5:00 am - 11:47 amOPO Porto-SEA Seattle/Tacoma Intl

14h 47m1 stop Amsterdam Schiphol

$1,109KLM

Wed, Sep 2 - Sat, Sep 12

1:50 pm - 3:30 pmSEA Seattle/Tacoma Intl-OPO Porto

17h 40m1 stop Amsterdam Schiphol

5:00 am - 4:35 pmOPO Porto-SEA Seattle/Tacoma Intl

19h 35m1 stop Amsterdam Schiphol

$1,109KLM

Tue, Sep 1 - Mon, Sep 14

5:50 am - 7:00 amSEA Seattle/Tacoma Intl-OPO Porto

17h 10m2 stops Vancouver Intl Montreal Pierre Elliott Trudeau Intl

12:20 pm - 10:05 amOPO Porto-SEA Seattle/Tacoma Intl

29h 45m2 stops Montreal Pierre Elliott Trudeau Intl Vancouver Intl

$1,114Air Canada

Wed, Sep 2 - Sat, Sep 12

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

19h 15m1 stop Paris Charles de Gaulle

6:10 am - 4:45 pmOPO Porto-SEA Seattle/Tacoma Intl

18h 35m2 stops Paris Charles de Gaulle Minneapolis St Paul

$1,121Air France

Wed, Sep 2 - Sat, Sep 12

10:58 pm - 6:55 amSEA Seattle/Tacoma Intl-OPO Porto

23h 57m1 stop Newark

12:20 pm - 7:14 pmOPO Porto-SEA Seattle/Tacoma Intl

38h 54m2 stops Montreal Pierre Elliott Trudeau Intl Chicago O'Hare Intl

$1,172United Airlines

Fri, Sep 4 - Sat, Sep 12

5:50 am - 7:10 amSEA Seattle/Tacoma Intl-OPO Porto

41h 20m2 stops Vancouver Intl Montreal Pierre Elliott Trudeau Intl

12:20 pm - 10:47 pmOPO Porto-SEA Seattle/Tacoma Intl

18h 27m2 stops Montreal Pierre Elliott Trudeau Intl Vancouver Intl

$1,184Air Canada

Thu, Sep 3 - Sat, Sep 12

Save money when you book flights with momondo

Big names and deals

Search 100s of travel sites to compare prices.

Filter for what you want

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

Trusted and free

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

Price Alerts

Not ready to book? to track prices.

Search flight deals

Icelandair flights from Seattle to Portugal

Our best Icelandair deals on Seattle to Portugal flight tickets

Icelandair

Dec 5

SEA2:35 pmSeattle/Tacoma Intl

14h 15m

1 stop

LIS12:50 pmLisbon Humberto Delgado

Dec 13

LIS2:00 pmLisbon Humberto Delgado

35h 00m

1 stop

SEA5:00 pmSeattle/Tacoma Intl

$702

Icelandair

Dec 5

SEA2:35 pmSeattle/Tacoma Intl

14h 15m

1 stop

LIS12:50 pmLisbon Humberto Delgado

Dec 13

LIS2:00 pmLisbon Humberto Delgado

35h 00m

1 stop

SEA5:00 pmSeattle/Tacoma Intl

$710

Icelandair

Jan 9

SEA2:35 pmSeattle/Tacoma Intl

14h 15m

1 stop

LIS12:50 pmLisbon Humberto Delgado

Jan 26

LIS11:35 amLisbon Humberto Delgado

13h 25m

1 stop

SEA5:00 pmSeattle/Tacoma Intl

$731

Air Canada flights from Seattle to Portugal

Our best Air Canada deals on Seattle to Portugal flight tickets

Air Canada

Oct 18

SEA8:00 amSeattle/Tacoma Intl

19h 05m

1 stop

LIS11:05 amLisbon Humberto Delgado

Nov 3

LIS6:05 amLisbon Humberto Delgado

20h 17m

2 stops

SEA6:22 pmSeattle/Tacoma Intl

$728

Air Canada

Oct 21

SEA5:50 amSeattle/Tacoma Intl

19h 30m

2 stops

LIS9:20 amLisbon Humberto Delgado

Nov 4

LIS5:00 amLisbon Humberto Delgado

21h 22m

2 stops

SEA6:22 pmSeattle/Tacoma Intl

$743

Air Canada

Nov 29

SEA7:45 amSeattle/Tacoma Intl

21h 05m

2 stops

OPO12:50 pmPorto

Dec 9

OPO6:00 amPorto

35h 27m

2 stops

SEA9:27 amSeattle/Tacoma Intl

$748

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

SeattleLisbon

SEA Seattle/Tacoma Intl - LIS Lisbon Humberto Delgado

SEALIS

Seattle/Tacoma Intl

Sat 12/5

2:35 pm-12:50 pm

1 stop14h 15m

Lisbon Humberto Delgado

Sun 12/13

2:00 pm-5:00 pm

1 stop35h 00m

$702

SeattleLisbon

SEA Seattle/Tacoma Intl - LIS Lisbon Humberto Delgado

SEALIS

Seattle/Tacoma Intl

Sat 12/5

2:35 pm-12:50 pm

1 stop14h 15m

Lisbon Humberto Delgado

Sun 12/13

2:00 pm-5:00 pm

1 stop35h 00m

$710

SeattlePorto

SEA Seattle/Tacoma Intl - OPO Porto

SEAOPO

Seattle/Tacoma Intl

Sun 10/18

6:50 pm-11:25 pm

1 stop20h 35m

Porto

Tue 11/3

1:45 pm-1:00 pm

1 stop31h 15m

$715

SeattlePorto

SEA Seattle/Tacoma Intl - OPO Porto

SEAOPO

Seattle/Tacoma Intl

Wed 1/6

2:50 pm-12:50 pm

1 stop14h 00m

Porto

Tue 3/2

6:00 am-6:20 pm

2 stops20h 20m

$717

SeattleLisbon

SEA Seattle/Tacoma Intl - LIS Lisbon Humberto Delgado

SEALIS

Seattle/Tacoma Intl

Wed 1/27

10:10 am-9:20 am

2 stops15h 10m

Lisbon Humberto Delgado

Wed 2/24

5:00 am-6:22 pm

2 stops21h 22m

$720

Quickest round-trip

SeattleLisbon

SEA Seattle/Tacoma Intl - LIS Lisbon Humberto Delgado

SEALIS

Seattle/Tacoma Intl

Sun 11/1

2:50 pm-1:30 pm

1 stop14h 40m

Lisbon Humberto Delgado

Fri 11/20

6:00 am-1:00 pm

1 stop15h 00m

$727

SeattleLisbon

SEA Seattle/Tacoma Intl - LIS Lisbon Humberto Delgado

SEALIS

Seattle/Tacoma Intl

Sun 10/18

8:00 am-11:05 am

1 stop19h 05m

Lisbon Humberto Delgado

Tue 11/3

6:05 am-6:22 pm

2 stops20h 17m

$728

SeattlePorto

SEA Seattle/Tacoma Intl - OPO Porto

SEAOPO

Seattle/Tacoma Intl

Sun 11/29

3:25 pm-9:55 pm

1 stop22h 30m

Porto

Wed 12/9

11:15 am-11:50 am

1 stop32h 35m

$743

SeattlePorto

SEA Seattle/Tacoma Intl - OPO Porto

SEAOPO

Seattle/Tacoma Intl

Sun 11/29

3:25 pm-9:55 pm

1 stop22h 30m

Porto

Mon 12/7

11:15 am-11:50 am

1 stop32h 35m

$743

SeattleLisbon

SEA Seattle/Tacoma Intl - LIS Lisbon Humberto Delgado

SEALIS

Seattle/Tacoma Intl

Sun 11/22

7:05 pm-10:40 am

2 stops31h 35m

Lisbon Humberto Delgado

Thu 12/3

5:00 am-6:22 pm

2 stops21h 22m

$743

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 $488, 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 $583.

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 $853 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 $755 on momondo.

Can stopping save me money on Seattle to Portugal flights?

You could potentially save up to 26% 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	$273
Fastest flight time	14h 00m
Direct flights	None

The best one-way flight to Portugal from Seattle in the past 72 hours is $273. The best round-trip flight deal from Seattle to Portugal found on momondo in the last 72 hours is $702.

The fastest flight from Seattle to Portugal takes 14h 00m

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 August 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 $348	Free Cancellation	Rating 6.9 738 reviews	Search Icelandair flights
Lufthansa	PriceFrom $471	Free Cancellation	Rating 6.8 8,226 reviews	Search Lufthansa flights
KLM	PriceFrom $481	Free Cancellation	Rating 7.8 1,568 reviews	Search KLM flights
British Airways	PriceFrom $482	Free Cancellation	Rating 6.7 8,198 reviews	Search British Airways flights
United Airlines	PriceFrom $482	Free Cancellation	Rating 7.4 10,148 reviews	Search United Airlines flights
American Airlines	PriceFrom $497	Free Cancellation	Rating 7.1 12,022 reviews	Search American Airlines flights
Air France	PriceFrom $504	Free Cancellation	Rating 7.5 1,644 reviews	Search Air France flights
Air Canada	PriceFrom $543	Free Cancellation	Rating 7.1 11,558 reviews	Search Air Canada flights
Delta	PriceFrom $554	Free Cancellation	Rating 7.8 8,537 reviews	Search Delta flights
Scandinavian Airlines	PriceFrom $567	Free Cancellation	Rating 7.4 1,968 reviews	Search Scandinavian Airlines 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.

Start using Trips

Find my bookings

Get notified when prices go down

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

1 adult

Wed 9/30

Wed 10/7

Email me momondo's favorite deals

By creating a price alert you accept our terms of use and privacy policy.

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 $554

Flights to Portofrom $527

Flights to Funchalfrom $551

Flights to Farofrom $633

Flights to Ponta Delgadafrom $572

Flights to Lajesfrom $568

Flights to Hortafrom $579

Flights to Pico Islandfrom $671

Flights to Porto Santofrom $725

Flights to Velasfrom $673

Cheap flights from Seattle to Portugal from $273

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 10/18. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

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

Trusted and free

Price Alerts

Price Alerts

Icelandair flights from Seattle to Portugal

Our best Icelandair deals on Seattle to Portugal flight tickets

Air Canada flights from Seattle to Portugal

Our best Air Canada 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