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

WestJet and British Airways 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 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 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.

$258 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

$698Icelandair

Sat, Dec 5 - Sun, Dec 13

7:00 pm - 12:35 pmSEA Seattle/Tacoma Intl-LIS Lisbon Humberto Delgado

33h 35m3 stops Reykjavik Keflavik Intl Stockholm Arlanda Warsaw Frederic Chopin

3:00 pm - 6:00 pmLIS Lisbon Humberto Delgado-SEA Seattle/Tacoma Intl

34h 00m3 stops Warsaw Frederic Chopin Stockholm Arlanda Reykjavik Keflavik Intl

$716Multiple Airlines

Mon, Oct 19 - Mon, Oct 26

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

14h 00m1 stop Munich Franz Josef Strauss

6:00 am - 6:22 pmOPO Porto-SEA Seattle/Tacoma Intl

20h 22m2 stops Frankfurt am Main Vancouver Intl

$717Multiple Airlines

Wed, Nov 11 - Thu, Dec 3

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

$723Icelandair

Sat, Nov 7 - Sun, Nov 22

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

14h 00m1 stop Munich Franz Josef Strauss

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

31h 15m1 stop Munich Franz Josef Strauss

$729Lufthansa

Wed, Nov 11 - Thu, Dec 3

7:55 am - 11:05 amSEA Seattle/Tacoma Intl-LIS Lisbon Humberto Delgado

19h 10m1 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

$729Air Canada

Sun, Oct 18 - Tue, Nov 3

7:15 am - 10:25 amSEA Seattle/Tacoma Intl-OPO Porto

19h 10m1 stop New York John F Kennedy Intl

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

32h 32m1 stop Amsterdam Schiphol

$735Delta

Sun, Oct 18 - Tue, Nov 3

3:15 pm - 10:40 amSEA Seattle/Tacoma Intl-LIS Lisbon Humberto Delgado

35h 25m2 stops Vancouver Intl Montreal Pierre Elliott Trudeau Intl

5:00 am - 12:00 pmLIS Lisbon Humberto Delgado-SEA Seattle/Tacoma Intl

15h 00m1 stop Frankfurt am Main

$736Lufthansa

Sun, Nov 8 - Wed, Nov 18

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

22h 30m1 stop Paris Charles de Gaulle

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

14h 47m1 stop Amsterdam Schiphol

$737Delta

Sun, Nov 8 - Tue, Nov 17

3:15 pm - 6:55 amSEA Seattle/Tacoma Intl-LIS Lisbon Humberto Delgado

31h 40m2 stops Vancouver Intl Montreal Pierre Elliott Trudeau Intl

5:00 am - 9:32 amLIS Lisbon Humberto Delgado-SEA Seattle/Tacoma Intl

36h 32m2 stops Frankfurt am Main Vancouver Intl

$743Air Canada

Tue, Nov 10 - Wed, Nov 18

Cheap last minute flights

Enter your travel dates to find the best prices.

7:10 pm - 5:50 pmSEA Seattle/Tacoma Intl-LIS Lisbon Humberto Delgado

14h 40m1 stop Dublin

6:00 am - 9:40 amLIS Lisbon Humberto Delgado-SEA Seattle/Tacoma Intl

35h 40m2 stops Halifax Intl Calgary

$939Multiple Airlines

Wed, Sep 9 - Mon, Sep 14

7:10 pm - 6:55 pmSEA Seattle/Tacoma Intl-LIS Lisbon Humberto Delgado

15h 45m1 stop Dublin

6:00 am - 9:40 amLIS Lisbon Humberto Delgado-SEA Seattle/Tacoma Intl

35h 40m2 stops Halifax Intl Calgary

$943Multiple Airlines

Mon, Sep 7 - Mon, Sep 14

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

20h 35m1 stop Munich Franz Josef Strauss

6:20 am - 4:59 pmOPO Porto-SEA Seattle/Tacoma Intl

18h 39m1 stop Munich Franz Josef Strauss

$1,039Lufthansa

Fri, Sep 11 - Wed, Oct 7

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

20h 35m1 stop Munich Franz Josef Strauss

6:20 am - 4:59 pmOPO Porto-SEA Seattle/Tacoma Intl

18h 39m1 stop Munich Franz Josef Strauss

$1,039Lufthansa

Fri, Sep 11 - Tue, Oct 6

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

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

6:00 am - 6:32 pmOPO Porto-SEA Seattle/Tacoma Intl

20h 32m2 stops Frankfurt am Main Vancouver Intl

$1,042Air Canada

Wed, Sep 9 - Tue, Oct 6

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

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

6:00 am - 2:22 pmOPO Porto-SEA Seattle/Tacoma Intl

40h 22m2 stops Frankfurt am Main Vancouver Intl

$1,042Air Canada

Wed, Sep 9 - Thu, Oct 8

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

19h 15m1 stop Paris Charles de Gaulle

11:35 am - 11:52 amOPO Porto-SEA Seattle/Tacoma Intl

32h 17m1 stop Amsterdam Schiphol

$1,043Delta

Wed, Sep 9 - Tue, Oct 6

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

19h 15m1 stop Paris Charles de Gaulle

5:00 am - 11:52 amOPO Porto-SEA Seattle/Tacoma Intl

14h 52m1 stop Amsterdam Schiphol

$1,043Delta

Wed, Sep 9 - Wed, Oct 7

7:30 am - 6:55 amSEA Seattle/Tacoma Intl-OPO Porto

15h 25m1 stop Newark

11:50 am - 7:14 pmOPO Porto-SEA Seattle/Tacoma Intl

39h 24m2 stops Montreal Pierre Elliott Trudeau Intl Chicago O'Hare Intl

$1,111United Airlines

Thu, Sep 10 - Thu, Sep 17

7:00 am - 6:55 amSEA Seattle/Tacoma Intl-OPO Porto

15h 55m2 stops Chicago O'Hare Intl Newark

11:50 am - 7:14 pmOPO Porto-SEA Seattle/Tacoma Intl

39h 24m2 stops Montreal Pierre Elliott Trudeau Intl Chicago O'Hare Intl

$1,116United Airlines

Thu, Sep 10 - Thu, Sep 17

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Air Canada flights from Seattle to Portugal

Our best Air Canada deals on Seattle to Portugal flight tickets

Air Canada

Oct 18

SEA7:55 amSeattle/Tacoma Intl

19h 10m

1 stop

LIS11:05 amLisbon Humberto Delgado

Nov 3

LIS6:05 amLisbon Humberto Delgado

20h 17m

2 stops

SEA6:22 pmSeattle/Tacoma Intl

$729

Air Canada

Nov 10

SEA3:15 pmSeattle/Tacoma Intl

31h 40m

2 stops

LIS6:55 amLisbon Humberto Delgado

Nov 18

LIS5:00 amLisbon Humberto Delgado

36h 32m

2 stops

SEA9:32 amSeattle/Tacoma Intl

$743

Air Canada

Oct 26

SEA8:40 amSeattle/Tacoma Intl

19h 00m

2 stops

LIS10:40 amLisbon Humberto Delgado

Nov 11

LIS5:00 amLisbon Humberto Delgado

23h 59m

2 stops

SEA8:59 pmSeattle/Tacoma Intl

$754

United Airlines flights from Seattle to Portugal

Our best United Airlines deals on Seattle to Portugal flight tickets

United Airlines

Nov 8

SEA8:09 amSeattle/Tacoma Intl

17h 56m

1 stop

LIS10:05 amLisbon Humberto Delgado

Nov 18

LIS5:00 amLisbon Humberto Delgado

15h 00m

1 stop

SEA12:00 pmSeattle/Tacoma Intl

$744

United Airlines

Nov 8

SEA8:09 amSeattle/Tacoma Intl

17h 56m

1 stop

LIS10:05 amLisbon Humberto Delgado

Nov 17

LIS12:50 pmLisbon Humberto Delgado

34h 42m

2 stops

SEA3:32 pmSeattle/Tacoma Intl

$747

United Airlines

Nov 7

SEA11:17 pmSeattle/Tacoma Intl

26h 48m

2 stops

LIS10:05 amLisbon Humberto Delgado

Nov 18

LIS5:00 amLisbon Humberto Delgado

15h 00m

1 stop

SEA12:00 pmSeattle/Tacoma Intl

$749

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

$698

SeattleLisbon

SEA Seattle/Tacoma Intl - LIS Lisbon Humberto Delgado

SEALIS

Seattle/Tacoma Intl

Mon 10/19

7:00 pm-12:35 pm

3 stops33h 35m

Lisbon Humberto Delgado

Mon 10/26

3:00 pm-6:00 pm

3 stops34h 00m

$716

Quickest round-trip

SeattlePorto

SEA Seattle/Tacoma Intl - OPO Porto

SEAOPO

Seattle/Tacoma Intl

Wed 11/11

2:50 pm-12:50 pm

1 stop14h 00m

Porto

Thu 12/3

6:00 am-6:22 pm

2 stops20h 22m

$717

SeattleLisbon

SEA Seattle/Tacoma Intl - LIS Lisbon Humberto Delgado

SEALIS

Seattle/Tacoma Intl

Sat 11/7

2:35 pm-12:50 pm

1 stop14h 15m

Lisbon Humberto Delgado

Sun 11/22

2:00 pm-5:00 pm

1 stop35h 00m

$723

SeattlePorto

SEA Seattle/Tacoma Intl - OPO Porto

SEAOPO

Seattle/Tacoma Intl

Wed 11/11

2:50 pm-12:50 pm

1 stop14h 00m

Porto

Thu 12/3

1:45 pm-1:00 pm

1 stop31h 15m

$729

SeattleLisbon

SEA Seattle/Tacoma Intl - LIS Lisbon Humberto Delgado

SEALIS

Seattle/Tacoma Intl

Sun 10/18

7:55 am-11:05 am

1 stop19h 10m

Lisbon Humberto Delgado

Tue 11/3

6:05 am-6:22 pm

2 stops20h 17m

$729

SeattlePorto

SEA Seattle/Tacoma Intl - OPO Porto

SEAOPO

Seattle/Tacoma Intl

Sun 10/18

7:15 am-10:25 am

1 stop19h 10m

Porto

Tue 11/3

11:15 am-11:47 am

1 stop32h 32m

$735

SeattleLisbon

SEA Seattle/Tacoma Intl - LIS Lisbon Humberto Delgado

SEALIS

Seattle/Tacoma Intl

Sun 11/8

3:15 pm-10:40 am

2 stops35h 25m

Lisbon Humberto Delgado

Wed 11/18

5:00 am-12:00 pm

1 stop15h 00m

$736

SeattlePorto

SEA Seattle/Tacoma Intl - OPO Porto

SEAOPO

Seattle/Tacoma Intl

Sun 11/8

3:25 pm-9:55 pm

1 stop22h 30m

Porto

Tue 11/17

5:00 am-11:47 am

1 stop14h 47m

$737

SeattleLisbon

SEA Seattle/Tacoma Intl - LIS Lisbon Humberto Delgado

SEALIS

Seattle/Tacoma Intl

Tue 11/10

3:15 pm-6:55 am

2 stops31h 40m

Lisbon Humberto Delgado

Wed 11/18

5:00 am-9:32 am

2 stops36h 32m

$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 $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 $852 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 7% 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	$258
Fastest flight time	13h 45m
Direct flights	None

The best one-way flight to Portugal from Seattle in the past 72 hours is $258. The best round-trip flight deal from Seattle to Portugal found on momondo in the last 72 hours is $698.

The fastest flight from Seattle to Portugal takes 13h 45m

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 $348	Free Cancellation	Rating 6.9 740 reviews	Search Icelandair flights
Lufthansa	PriceFrom $471	Free Cancellation	Rating 6.8 8,225 reviews	Search Lufthansa flights
KLM	PriceFrom $481	Free Cancellation	Rating 7.8 1,569 reviews	Search KLM flights
British Airways	PriceFrom $482	Free Cancellation	Rating 6.7 8,207 reviews	Search British Airways flights
United Airlines	PriceFrom $482	Free Cancellation	Rating 7.4 10,174 reviews	Search United Airlines flights
American Airlines	PriceFrom $497	Free Cancellation	Rating 7.1 12,045 reviews	Search American Airlines flights
Air France	PriceFrom $504	Free Cancellation	Rating 7.5 1,645 reviews	Search Air France flights
Air Canada	PriceFrom $543	Free Cancellation	Rating 7.1 11,586 reviews	Search Air Canada flights
Delta	PriceFrom $554	Free Cancellation	Rating 7.8 8,574 reviews	Search Delta flights
Scandinavian Airlines	PriceFrom $567	Free Cancellation	Rating 7.4 1,979 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.

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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 $509

Flights to Portofrom $539

Flights to Funchalfrom $554

Flights to Farofrom $574

Flights to Ponta Delgadafrom $554

Flights to Lajesfrom $577

Flights to Hortafrom $591

Flights to Pico Islandfrom $561

Flights to Porto Santofrom $942

Flights to Velasfrom $692

Cheap flights from Seattle to Portugal from $258

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 10/9. 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

Air Canada flights from Seattle to Portugal

Our best Air Canada deals on Seattle to Portugal flight tickets

United Airlines flights from Seattle to Portugal

Our best United Airlines 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