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

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

What airlines fly to Portugal?

British Airways, United Airlines and Delta are the top three most popular airlines that fly to Portugal from Seattle according to our data. British Airways is the first choice among our users, with 33% of people opting to fly with this airline when traveling to Portugal. Keep in mind that there are 13 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 13 as of February 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.

$216 Cheap Flights from Seattle to Portugal in 2026

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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.

8:20 pm - 11:00 pm

SEA

LIS

18h 40m

1 stop

11:05 am - 9:23 pm

LIS

SEA

18h 18m

1 stop

$491British Airways

Tue, Apr 7 - Wed, Apr 15

10:20 am - 11:05 am

SEA

LIS

40h 45m

2 stops

5:55 am - 6:30 pm

LIS

SEA

20h 35m

2 stops

$492Multiple Airlines

Mon, Apr 27 - Tue, May 5

1:35 pm - 11:00 pm

SEA

LIS

25h 25m

1 stop

6:35 am - 10:38 pm

LIS

SEA

24h 03m

2 stops

$494Multiple Airlines

Tue, Apr 21 - Sat, May 2

8:00 pm - 11:05 am

SEA

LIS

55h 05m

2 stops

11:25 am - 9:15 am

LIS

SEA

53h 50m

2 stops

$505Air Canada

Sun, Apr 19 - Mon, May 4

8:00 am - 10:15 am

SEA

LIS

19h 15m

1 stop

6:10 am - 8:56 pm

LIS

SEA

21h 46m

2 stops

$506United Airlines

Tue, Mar 10 - Wed, Mar 18

10:20 am - 11:05 am

SEA

LIS

40h 45m

2 stops

1:00 pm - 9:08 pm

LIS

SEA

16h 08m

1 stop

$510Air Canada

Mon, Apr 27 - Tue, May 5

7:30 am - 6:55 am

SEA

OPO

15h 25m

1 stop

2:25 pm - 11:59 pm

OPO

SEA

17h 34m

2 stops

$578United Airlines

Wed, Aug 12 - Wed, Sep 2

6:40 pm - 10:00 pm

SEA

OPO

19h 20m

1 stop

5:00 am - 11:45 am

OPO

SEA

14h 45m

1 stop

$583Delta

Mon, Apr 13 - Wed, Apr 29

7:20 am - 10:30 am

SEA

OPO

19h 10m

1 stop

8:10 pm - 4:35 pm

OPO

SEA

28h 25m

1 stop

$588KLM

Wed, Aug 12 - Mon, Aug 31

5:35 pm - 10:15 pm

SEA

OPO

20h 40m

1 stop

6:50 pm - 11:45 am

OPO

SEA

24h 55m

1 stop

$589KLM

Tue, Apr 14 - Tue, Apr 28

United Airlines flights from Seattle to Portugal

Our best United Airlines deals on Seattle to Portugal flight tickets

United Airlines

Mar 10

SEA8:00 amSeattle/Tacoma Intl

19h 15m

1 stop

LIS10:15 amLisbon Humberto Delgado

Mar 18

LIS6:10 amLisbon Humberto Delgado

21h 46m

2 stops

SEA8:56 pmSeattle/Tacoma Intl

$506

United Airlines

Mar 10

SEA7:00 amSeattle/Tacoma Intl

20h 15m

2 stops

LIS10:15 amLisbon Humberto Delgado

Mar 18

LIS6:10 amLisbon Humberto Delgado

21h 46m

2 stops

SEA8:56 pmSeattle/Tacoma Intl

$511

United Airlines

Mar 23

SEA8:00 amSeattle/Tacoma Intl

18h 20m

1 stop

LIS9:20 amLisbon Humberto Delgado

Apr 1

LIS12:20 pmLisbon Humberto Delgado

29h 26m

2 stops

SEA9:46 amSeattle/Tacoma Intl

$516

Delta flights from Seattle to Portugal

Our best Delta deals on Seattle to Portugal flight tickets

Delta

Apr 14

SEA6:40 pmSeattle/Tacoma Intl

15h 10m

1 stop

LIS5:50 pmLisbon Humberto Delgado

May 4

LIS5:35 amLisbon Humberto Delgado

20h 04m

1 stop

SEA5:39 pmSeattle/Tacoma Intl

$548

Delta

Apr 23

SEA7:15 amSeattle/Tacoma Intl

19h 40m

2 stops

LIS10:55 amLisbon Humberto Delgado

Apr 27

LIS5:00 amLisbon Humberto Delgado

14h 45m

1 stop

SEA11:45 amSeattle/Tacoma Intl

$550

Delta

Apr 14

SEA6:40 pmSeattle/Tacoma Intl

15h 10m

1 stop

LIS5:50 pmLisbon Humberto Delgado

Apr 27

LIS5:00 amLisbon Humberto Delgado

20h 16m

2 stops

SEA5:16 pmSeattle/Tacoma Intl

$551

Fly from

Fly to

Route

Depart

Return

Price

SeattleLisbon

SEA - LIS

SEALIS

Seattle/Tacoma Intl

Tue 4/7

8:20 pm-11:00 pm

1 stop18h 40m

Lisbon Humberto Delgado

Wed 4/15

11:05 am-9:23 pm

1 stop18h 18m

$491

SeattleLisbon

SEA - LIS

SEALIS

Seattle/Tacoma Intl

Mon 4/27

10:20 am-11:05 am

2 stops40h 45m

Lisbon Humberto Delgado

Tue 5/5

5:55 am-6:30 pm

2 stops20h 35m

$492

SeattleLisbon

SEA - LIS

SEALIS

Seattle/Tacoma Intl

Tue 4/21

1:35 pm-11:00 pm

1 stop25h 25m

Lisbon Humberto Delgado

Sat 5/2

6:35 am-10:38 pm

2 stops24h 03m

$494

SeattleLisbon

SEA - LIS

SEALIS

Seattle/Tacoma Intl

Sun 4/19

8:00 pm-11:05 am

2 stops55h 05m

Lisbon Humberto Delgado

Mon 5/4

11:25 am-9:15 am

2 stops53h 50m

$505

SeattleLisbon

SEA - LIS

SEALIS

Seattle/Tacoma Intl

Tue 3/10

8:00 am-10:15 am

1 stop19h 15m

Lisbon Humberto Delgado

Wed 3/18

6:10 am-8:56 pm

2 stops21h 46m

$506

SeattleLisbon

SEA - LIS

SEALIS

Seattle/Tacoma Intl

Mon 4/27

10:20 am-11:05 am

2 stops40h 45m

Lisbon Humberto Delgado

Tue 5/5

1:00 pm-9:08 pm

1 stop16h 08m

$510

SeattlePorto

SEA - OPO

SEAOPO

Seattle/Tacoma Intl

Wed 8/12

7:30 am-6:55 am

1 stop15h 25m

Porto

Wed 9/2

2:25 pm-11:59 pm

2 stops17h 34m

$578

SeattlePorto

SEA - OPO

SEAOPO

Seattle/Tacoma Intl

Mon 4/13

6:40 pm-10:00 pm

1 stop19h 20m

Porto

Wed 4/29

5:00 am-11:45 am

1 stop14h 45m

$583

SeattlePorto

SEA - OPO

SEAOPO

Seattle/Tacoma Intl

Wed 8/12

7:20 am-10:30 am

1 stop19h 10m

Porto

Mon 8/31

8:10 pm-4:35 pm

1 stop28h 25m

$588

SeattlePorto

SEA - OPO

SEAOPO

Seattle/Tacoma Intl

Tue 4/14

5:35 pm-10:15 pm

1 stop20h 40m

Porto

Tue 4/28

6:50 pm-11:45 am

1 stop24h 55m

$589

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 $492, 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 $560.

How far in advance should I book a flight 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 $823 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 $738 on momondo.

Can stopping save me money on Seattle to Portugal flights?

You could potentially save up to 24% 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

Fastest flight time	12h 35m
Direct flights	None

The fastest flight from Seattle to Portugal takes 12h 35m

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

Search flight deals

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 13 as of February 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 7.1 617 reviews	Search Icelandair flights
KLM	PriceFrom $481	Free Cancellation	Rating 7.7 1,460 reviews	Search KLM flights
British Airways	PriceFrom $482	Free Cancellation	Rating 6.7 7,768 reviews	Search British Airways flights
Lufthansa	PriceFrom $484	Free Cancellation	Rating 6.8 7,810 reviews	Search Lufthansa flights
United Airlines	PriceFrom $494	Free Cancellation	Rating 7.4 9,348 reviews	Search United Airlines flights
Air France	PriceFrom $530	Free Cancellation	Rating 7.4 1,538 reviews	Search Air France flights
Air Canada	PriceFrom $543	Free Cancellation	Rating 7.1 10,747 reviews	Search Air Canada flights
Delta	PriceFrom $554	Free Cancellation	Rating 7.9 8,237 reviews	Search Delta flights
American Airlines	PriceFrom $558	Free Cancellation	Rating 7.2 11,352 reviews	Search American Airlines flights
SWISS	PriceFrom $562	Free Cancellation	Rating 7.6 1,881 reviews	Search SWISS 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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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 $397

Flights to Portofrom $376

Flights to Funchalfrom $431

Flights to Farofrom $416

Flights to Ponta Delgadafrom $449

Flights to Lajesfrom $560

Flights to Pico Islandfrom $575

Flights to Hortafrom $549

Flights to Porto Santofrom $471

Flights to Velasfrom $549

Cheap flights from Seattle to Portugal from $216

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 4/20. 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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United Airlines flights from Seattle to Portugal

Our best United Airlines deals on Seattle to Portugal flight tickets

Delta flights from Seattle to Portugal

Our best Delta deals on Seattle to Portugal flight tickets

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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 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

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

Fastest flight time

Direct flights

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