$663 Cheap Swiss International Air Lines flights Seattle (SEA) to Kos (KGS)

View $663 flight on Fri, Sep 19, 2025Opens in a new window

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$663 Cheap Swiss International Air Lines flights Seattle (SEA) to Kos (KGS)

Prices were available within the past 7 days and start at $663 for one-way flights and for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Flights from Seattle (SEA) to Kos (KGS)
Origin airport
Seattle - Tacoma Intl.
Destination airport
Kos Island Intl.
Distance
6316 mi

Frequently asked questions

How much is a SWISS flight from Seattle - Tacoma Intl. Airport (SEA) to Kos Island Intl. Airport (KGS)?
Set the "Price (lowest to highest)" filter on Expedia to look for cheap SWISS round-trip flights from SEA to KGS. Affordable one-way fares from $663 are also on offer.**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 KGS with SWISS?
Search for return or one-way flights to Kos in December or February. You could find lower fares with SWISS during these off-peak months.
What is the cheapest time to book flights from Seattle - Tacoma Intl. Airport (SEA) to Kos Island Intl. Airport (KGS) with SWISS?
Search for SWISS flights from SEA to KGS about one month before you want to go. The cheapest time to reserve an international flight is generally 18 to 29 days ahead of your departure date when you can save 17% versus booking four to five months in advance. Regardless of fare class or itinerary, the best day to book international airfare is usually Sunday. Friday can be the most expensive. Passengers who book on a Sunday can save an average of 17% compared to those who book on a Friday.**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 SWISS fly nonstop from Seattle - Tacoma Intl. Airport (SEA) to Kos Island Intl. Airport (KGS)?
To find out if there's a direct trip from SEA to KGS with SWISS or other carriers, use our "Nonstop" filter when browsing for flights.
What is the earliest SWISS flight from SEA to KGS?
To find the earliest departures from SEA to KGS with SWISS, filter your search by "Morning" and "Early Morning." Booking an early flight usually means you're less likely to experience 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 SWISS fly into in Kos?
Get on a SWISS flight from Seattle - Tacoma Intl. Airport (SEA) to Kos, and you'll likely touch down at Kos Island Intl. Airport (KGS). This is the airline's primary hub here.
What kind of luggage can I take on a SWISS flight from Seattle - Tacoma Intl. Airport (SEA) to Kos Island Intl. Airport (KGS)?
On a standard economy flight with SWISS from SEA to KGS, passengers can bring 1 checked-in bag up to 50 lb with dimensions no larger than 62 inches in total. For carry-on, you can have 1 cabin bag weighing up to 17 lb and measuring no more than 22 inches x 21 inches x 5 inches. Weight and size limits can differ based on your fare type and cabin class. To make sure you're not hit with additional fees at the airport, check your SWISS booking or look up the airline's website before packing your bags.
Why fly with SWISS from SEA to KGS?
With a rewarding loyalty program and a 4-star airline rating, SWISS is a favorite for many passengers flying from SEA to KGS. Also, if you're a Swiss Miles & More and One Key™ member booking with Expedia, you could earn OneKeyCash™* on eligible flights on top of your airline miles, which can be used on future travel.*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 SWISS flight from Seattle - Tacoma Intl. Airport (SEA) to Kos Island Intl. Airport (KGS)?
Depending on the ticket type you purchased, a fee typically applies if you cancel or reschedule your flight more than 24 hours after it has been confirmed. To secure tickets with more flexibility, select our "Changes included" or "No cancel fee" filter when looking for flights. To learn more about canceling or modifying your reservation, head to "Trips," select your flight and tick "Manage Booking."

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*Available to One Key members.