$357 Cheap United flights from Seattle to Lisbon (SEA to LIS)

Find The Best Day To Fly from Seattle to Lisbon

Amazing United SEA to LIS Flight Deals

The cheapest flights to Humberto Delgado found within the past 7 days were $529 round trip and $357 one way. Prices and availability subject to change. Additional terms may apply.

Thu, Mar 19 - Fri, Mar 27
SEA
Seattle
LIS
Lisbon
$529 Roundtrip, found 2 days ago
$529
Roundtrip
found 2 days ago
Select United flight, departing Thu, Mar 19 from Seattle to Lisbon, returning Fri, Mar 27, priced at $529 found 2 days ago
Thu, Mar 19 - Fri, Mar 27
SEA
Seattle
LIS
Lisbon
$541 Roundtrip, found 2 days ago
$541
Roundtrip
found 2 days ago
Select United flight, departing Thu, Mar 19 from Seattle to Lisbon, returning Fri, Mar 27, priced at $541 found 2 days ago
Thu, Mar 19 - Mon, Mar 30
SEA
Seattle
LIS
Lisbon
$545 Roundtrip, found 2 days ago
$545
Roundtrip
found 2 days ago
Select United flight, departing Thu, Mar 19 from Seattle to Lisbon, returning Mon, Mar 30, priced at $545 found 2 days ago

LIS From SEA Economy Coach Packages on Similar Airlines

Price found within the past 48 hours. Click for updated prices.
Eurostars Universal Lisboa

Eurostars Universal Lisboa

5 out of 5
per person
Sep 7 - Sep 13
found 9 hours ago
Roundtrip non-stop flight included
Seattle (SEA) to Lisbon (LIS)
Eurostars Lisboa Baixa

Eurostars Lisboa Baixa

4 out of 5
per person
Aug 25 - Aug 30
found 3 hours ago
Roundtrip flight included
Seattle (SEA) to Lisbon (LIS)
The Emerald House Lisbon, Curio Collection By Hilton

The Emerald House Lisbon, Curio Collection By Hilton

4 out of 5
per person
Sep 7 - Sep 13
found 9 hours ago
Roundtrip non-stop flight included
Seattle (SEA) to Lisbon (LIS)
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Frequently asked questions

Can I catch a flight from SEA to Lisbon/Portela Airport right now?
For information on any present Lisbon/Portela Airport travel advice and quarantine requirements, visit our Covid-19 Travel Advisor. Check before you book your flight, so you don't get caught out.
What terminal is United Airlines at Sea-Tac Airport?
If you're booked with United Airlines from SEA to Lisbon Airport, you might be able to find out the terminal information once you're issued with your boarding pass. If not, contact your airline.
Are there United Airlines non-stop flights from SEA to LIS?
There aren't any direct flights with United Airlines from Sea-Tac Airport to Humberto Delgado Airport (LIS). You will have a stopover, so make the most of this time to go for a stroll and stretch out those legs before jumping on your connecting flight.
How long is a United Airlines flight from SEA to LIS?
If you're jetting from Sea-Tac Airport to Lisbon/Portela Airport with United Airlines, buckle your seat belt and make yourself comfortable. This flight takes around 12 hours and 16 minutes, so get a little sleep if you want to start your vacation without jet lag.
How many direct and indirect flights does United Airlines fly from SEA to LIS?
No fewer than 7 United Airlines flights connect SEA and LIS per week.
If I am not able to travel due to COVID-19, can I change my booking to a later date?
For more info about changing your flight to Lisbon Airport, please visit our Customer Service Portal.
What is the best day to buy a plane ticket?
This just in! Airfares offered on Thursdays tend to be the cheapest, according to flight demand on Travelocity in 2021. Tuesday and Wednesday prices are also good, but you may want to prepare your budget if booking during the weekend, as data shows that is when prices are generally at their highest.
What are the cheapest days to fly?
Frequent travelers may already know this, but earlier in the week can be the cheapest time to fly. In 2021, flights departing on a Monday were generally the cheapest of the week, whereas you may pay a premium for weekend flights when demand is usually high. On average, tickets were most expensive for Saturday departures, so if you need to fly out on a weekend, you might look for deals ahead of time.
How far in advance can you book a flight?
Trying to figure out how early you should book your flight? It's possible to start comparing international airfares on Travelocity up to 12 months in advance. However, it does depend on the carrier as not all airlines release their prices that far out. According to our 2021 flight demand trends, last minute planners can still bag a bargain with some of the cheapest fares appearing 0-2 weeks prior to their travel dates.*According to flight demand on Travelocity.com from January to December 2021. Savings are subject to change based on departure location, date and destination.

Discover our best United flight from Seattle SEA to Lisbon LIS 

To find the best deals on flights to Seattle from Lisbon with United, just enter your travel dates, filter by United, and hit search. You’ll find flights to choose from and can sort by price, flight duration, and arrival or departure time.  

 

Return flights from Seattle SEA to Lisbon LIS with United 

If you’re planning a round trip, booking return flights with United is usually the most cost-effective option. With airfares ranging from $529 to $545, it’s easy to find a flight that suits your budget. Prices and availability subject to change. Additional terms may apply. 

 

Book one-way United flights from Seattle SEA to Lisbon LIS 

A one-way ticket gives you much greater flexibility—allowing you to choose your return date, destination, and time whenever you’re ready. By booking in advance you can find great deals on one-way tickets too. Right now, a one-way United flight from Seattle to Lisbon costs from $357. Prices and availability subject to change. Additional terms may apply. 

 

The easy way to find cheap flights to Lisbon LIS from  Seattle SEA with United 

To find a cheap United flight from Seattle SEA to Lisbon LIS, sort your search results by price or filter by budget. Thanks to Travelocity’s Price Match Promise, if you find a better airfare deal anywhere else within 24 hours, we’ll credit or refund the difference. 

 

How to find our best airfare deals on United flights from Seattle SEA to Lisbon LIS 

If you’re looking for cheap flights, it helps to be flexible when it comes to your travel dates. You’ll usually find lower cost tickets when you travel during quieter months such as March, or if you book a flight with a stopover. 

 

Find nonstop flights from Seattle SEA to Lisbon LIS with United 

If you’re keen to be on Lisbon soil fast, don’t waste time with a stopover—filter your search results to show direct United flights only. The journey takes around hour(s) min(s) – so you’ll be there before you know it. 

 

Flexible airline tickets for United flights from Seattle SEA to Lisbon LIS 

Make sure you’re not out of pocket if plans change by choosing a flexible ticket with penalty-free amendment and cancellation options. Use our ‘no change fee’ filter to see which flights have this option.  

 

There are a lot of reasons to book your flights to Lisbon LIS from  Seattle SEA with United on Travelocity 

At Travelocity our vast and up-to-the-minute inventory puts all of our best flight deals in one place. So, whether you’re traveling on business or jetting off with friends and family, you can trust Travelocity to get you there.

United Airports
Hop on a(n) United flight today by flying to many destinations out of these domestic and international airports:
Airport code
Country
Airport name
Number of flights
ORDUSAO'Hare Intl.227
DENUSADenver Intl.226
IAHUSAGeorge Bush Intercontinental136
IADUSAWashington Dulles Intl.100
SFOUSASan Francisco Intl.64
LAXUSALos Angeles Intl.23
EWRUSALiberty Intl.20
FRADEUFrankfurt Intl.19
NRTJPNNarita Intl.19
PEKCHNCapital Intl.16

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Hotel Star Inn Lisbon Aeroporto
Hotel Star Inn Lisbon Aeroporto
3 out of 5
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Meliá Lisboa Aeroporto
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4 out of 5
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A full-service spa, an indoor pool, and a restaurant are all featured at this smoke-free hotel. Traveling on business? Take advantage of the business center, ...
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Radisson Blu Hotel
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4 out of 5
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This hotel features a restaurant, a 24-hour gym, and a bar/lounge. WiFi in public areas is free. Self parking, a business center, and a snack bar/deli are also ...
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"It was clean and the restaurant was excellent."

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Radisson Blu Hotel
Lowest nightly price found within the past 24 hours based on a 1 night stay for 2 adults. Prices and availability subject to change. Additional terms may apply.
*Price based on the lowest price found within past 24 hours and based upon one night stay for two adults over the next thirty days. Prices and availability subject to change. Additional terms may apply.