$578 Cheap KLM flights Seattle (SEA) to Southampton (SOU)

View $578 flight on Sun, Nov 30, 2025Opens in a new window

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$578 Cheap KLM flights Seattle (SEA) to Southampton (SOU)

Prices were available within the past 7 days and start at $578 for one-way flights and $966 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

KLM
Sun, Aug 10 - Tue, Aug 26
SEA
Seattle
SOU
Southampton
$966 Roundtrip, found 19 hours ago
$966
Roundtrip
found 19 hours ago
Select KLM flight, departing Sun, Aug 10 from Seattle to Southampton, returning Tue, Aug 26, priced at $966 found 19 hours ago
Flights from Seattle (SEA) to Southampton (SOU)
Origin airport
Seattle - Tacoma Intl.
Destination airport
Southampton
Airlines serving
Aer Lingus, Delta, KLM, Virgin Atlantic
Popular airline
Aer Lingus
Distance
4789 mi

Frequently asked questions

How much is a KLM flight from Seattle - Tacoma Intl. Airport (SEA) to Southampton Airport (SOU)?
Use the "Price (lowest to highest)" filter on Expedia to look for cheap KLM round-trip flights from $966 from SEA to SOU. Affordable one-way tickets from $578 are available too.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.
What is the cheapest month to fly from SEA to SOU with KLM?
Look for one-way or return flights to Southampton in January or February. You could find lower fares with KLM during these quieter months.
What is the cheapest time to book flights from Seattle - Tacoma Intl. Airport (SEA) to Southampton Airport (SOU) with KLM?
To discover affordable flights from SEA to SOU with KLM, begin your search about one month before your planned departure. You can save 17% when you book your international tickets 18 to 29 days ahead instead of booking four to five months in advance. Another good tip? Booking on Sunday can lead to average savings of 17% compared to Friday (the most expensive day).**Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC's global airline sales database.
Does KLM fly nonstop from Seattle - Tacoma Intl. Airport (SEA) to Southampton Airport (SOU)?
Click on our "Nonstop" filter when browsing for direct KLM flights from SEA to SOU. It's also a great way to compare other airlines servicing the same nonstop trip.
What is the earliest KLM flight from SEA to SOU?
To find the earliest departure from SEA to SOU with KLM, sort your results by "Morning" and "Early Morning." Booking an early flight usually means you'll experience fewer cancellations.**Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
What airports does KLM fly into in Southampton?
Southampton Airport (SOU) is the primary Southampton hub for KLM flights from Seattle - Tacoma Intl. Airport (SEA).
Why fly with KLM from SEA to SOU?
Fly from SEA to SOU with KLM and you'll enjoy a range of perks starting with a 4-star airline rating. When you book through Expedia as a KLM Flying Blue and One Key™ member, you could also earn OneKeyCash™* to redeem on select future travel purchases.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.
Can I change or cancel my KLM flight from Seattle - Tacoma Intl. Airport (SEA) to Southampton Airport (SOU)?
Typically, you can reschedule or cancel your flight, although there may be additional charges if you booked more than 24 hours ago. Want to keep your options open? Make use of Expedia's "Changes included" and "No cancel fee" filters to find flights that won't penalize you if you need to alter your plans. To make changes, visit "Trips," select your flight and click on "Manage Booking" for more details.

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*Available to One Key members.