Ko Samui

$444+ Cheap flights from Seattle (SEA) to Ko Samui (USM)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 4/1. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — USM
Dec 26 — Jan 21
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Find cheap flights from Seattle to Ko Samui with Cheapflights

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Cheap flight deals from Seattle to Ko Samui

Discover tips and strategies to find the most affordable flight options for your journey from Seattle (SEA) to Ko Samui (USM). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated November 26, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$917
(Trip.com)

One-way from

$444
(Kiwi.com)
Provider with most accurate pricing for Seattle/Tacoma Intl-Ko Samui flight deals.
Provider most trusted by Cheapflights users for Seattle/Tacoma Intl-Ko Samui flights.
From Seattle/Tacoma Intl to Ko Samui
One-way flight from Seattle/Tacoma Intl to Ko Samui

Find flight deals from Seattle to Ko Samui

Best flights from Seattle to Ko Samui
Discover carefully curated flight deals from Seattle to Ko Samui that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated November 26, 2025.

This Trip.com deal was found by Cheapflights users on 11/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 2/2812:10 amSEA - USM
2 stops26h 40mMultiple Airlines
Sun 3/227:00 amUSM - SEA
2 stops21h 55mMultiple Airlines
Deal found 11/24$917
This EVA Air deal was found by Cheapflights users on 11/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure EVA Air is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 1/2412:10 amSEA - USM
2 stops25h 50mEVA Air
Wed 1/289:00 amUSM - SEA
2 stops24h 10mEVA Air
Deal found 11/23$1,072
This Singapore Airlines deal was found by Cheapflights users on 11/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Singapore Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 1/258:45 amSEA - USM
1 stop32h 15mSingapore Airlines
Wed 1/288:55 amUSM - SEA
1 stop37h 15mSingapore Airlines
Deal found 11/23$1,101
This oojo deal was found by Cheapflights users on 11/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 1/1011:30 pmSEA - USM
2 stops25h 10mEVA Air
Sat 1/179:00 amUSM - SEA
2 stops23h 30mEVA Air
Deal found 11/25$1,141
This FlightHub deal was found by Cheapflights users on 11/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 3/18:45 amSEA - USM
1 stop41h 25mSingapore Airlines
Sun 3/226:05 pmUSM - SEA
1 stop52h 05mSingapore Airlines
Deal found 11/24$1,257

Cheapflights Fare Finder

 
Customize your flight search to find flights from Seattle to Ko Samui that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated November 26, 2025.
Use the filters below to find and compare flights from Seattle to Ko Samui that are best for you.

Fly from

Seattle

Fly to

Ko Samui

Route

Depart

Return

Price

SeattleKo Samui

SEA - USM

SEAUSM

Seattle/Tacoma Intl

Sat 2/28

12:10 am-5:50 pm

2 stops26h 40m

Ko Samui

Sun 3/22

7:00 am-2:55 pm

2 stops21h 55m

$917

SeattleKo Samui

SEA - USM

SEAUSM

Seattle/Tacoma Intl

Sat 1/24

12:10 am-5:00 pm

2 stops25h 50m

Ko Samui

Wed 1/28

9:00 am-6:10 pm

2 stops24h 10m

$1,072

SeattleKo Samui

SEA - USM

SEAUSM

Seattle/Tacoma Intl

Sun 1/25

8:45 am-8:00 am

1 stop32h 15m

Ko Samui

Wed 1/28

8:55 am-7:10 am

1 stop37h 15m

$1,101

SeattleKo Samui

SEA - USM

SEAUSM

Seattle/Tacoma Intl

Sat 1/10

11:30 pm-3:40 pm

2 stops25h 10m

Ko Samui

Sat 1/17

9:00 am-5:30 pm

2 stops23h 30m

$1,141

SeattleKo Samui

SEA - USM

SEAUSM

Seattle/Tacoma Intl

Sun 3/1

8:45 am-5:10 pm

1 stop41h 25m

Ko Samui

Sun 3/22

6:05 pm-8:10 am

1 stop52h 05m

$1,257

SeattleKo Samui

SEA - USM

SEAUSM

Seattle/Tacoma Intl

Wed 4/1

11:05 pm-7:20 am

2 stops42h 15m

$444

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/25

Compare providers for flights from Seattle to Ko Samui

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Seattle to Ko Samui in November.
ProviderPrice AccuracyTrust Score*
AranGrantPrice Accuracy2 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star
eDreamsPrice Accuracy3 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Seattle-Ko Samui flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Seattle-Ko Samui flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from Seattle-Ko Samui flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Seattle-Ko Samui flights, Cheapflights users trust eDreams the most. eDreams has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Seattle-Ko Samui flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from Seattle to Ko Samui

Have a flexible travel schedule? Discover the best time to fly to Ko Samui from Seattle with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Seattle to Ko Samui

What is the cheapest time of day to fly from SEA to USM?

Find hourly flight availability from Seattle to Ko Samui. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated November 26, 2025.

When flying from Seattle to Ko Samui, the time of day you fly usually plays a role in the price. Save by searching for a flight in the afternoon, which can drop the price by up to 33% versus a flight in the evening.

What is the cheapest day to fly from Seattle to Ko Samui?

Use this chart to determine the cheapest time to fly round-trip from Seattle to Ko Samui. Price data was last updated on March 30, 2025.

Travelers seeking maximum savings on their Seattle to Ko Samui flight should consider departing on Monday afternoons when fares are most often at their lowest. Sunday mornings flights should be avoided if possible as fares are typically the most expensive at this time.

The best insider tips for Seattle to Ko Samui flights

Snippets provided in this section are AI-generated based on a summarization of Cheapflights-commissioned articles. The articles are presented as-is, for general informational purposes only, and may not be up-to-date. The opinions contained in the articles are original to the author and reflect their authentic experience, which may vary significantly from the experience of others.
Cheapflights partnered with top experts to bring you the best recommendations for your Seattle to Ko Samui trip
Airlines
Alaska Airlines

Enjoy free cocktails in Premium Class, though snacks and meals require purchase or pre-order.


Alaska Airlines offers Wi-Fi for a flat fee, ideal for long flights to stay productive.

Sun Country Air

Sun Country's priority check-in includes access to priority security lanes for a smoother experience.


Sun Country offers free inflight entertainment streamed to your device, but no onboard internet access.

Our travel experts
Robert Schrader

Robert Schrader

Expert on Alaska Airlines

Robert Schrader

Robert Schrader

One of the web's original travel bloggers, Robert launched his first site Leave Your Daily Hell in 2009. Since then, he's expanded into destination niche sites (one each for Japan, Thailand and Taiwan), in addition to having written for the inflight magazines of Singapore Airlines and Korean Air. Overall, he's visited nearly 100 countries, and flies business as often as possible.

Read more
Jennifer Simonson

Jennifer Simonson

Expert on Sun Country Air

Jennifer Simonson

Jennifer Simonson

Jennifer Simonson is driven by her lifelong commitment to exploring the globe. Her insatiable curiosity had led her to immerse herself into diverse locations like Oklahoma City and Pismo. Her hotel recommendations are the result of the myriad hotels she's stayed at across her travels. Along her journey, she cherishes engaging conversations with locals, indulging in the finest ice cream, trying her hand at surfing, and embarking on nature-filled hikes.

Read more

Reviews of airlines servicing Ko Samui

Get insights into the airlines that provide service to Ko Samui. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Ko Samui. Reviews last updated November 26, 2025.
Read reviews from past customers who have flown EVA Air and Singapore Airlines from Seattle to Ko Samui. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.

Overall

8.4

Entertainment

8.0

Boarding

8.4

Crew

8.6

Comfort

8.3

Food

8.1

Reviews

1 / 20
10.0
Excellent

Walter,Nov 2025

LAX - TPE

Everything went well. The crew was very friendly and efficient and they made a long flight enjoyable.

Overall

8.4

Entertainment

8.0

Boarding

8.4

Crew

8.6

Comfort

8.3

Food

8.1

Reviews

1 / 20
10.0
Excellent

Walter,Nov 2025

LAX - TPE

Everything went well. The crew was very friendly and efficient and they made a long flight enjoyable.

Overall

8.4

Entertainment

8.0

Boarding

8.4

Crew

8.6

Comfort

8.3

Food

8.1

Reviews

1 / 20
10.0
Excellent

Walter,Nov 2025

LAX - TPE

Everything went well. The crew was very friendly and efficient and they made a long flight enjoyable.

Related info for your journey

Find useful and relevant information for your journey from Seattle to Ko Samui. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
  • How long is the flight from Seattle to Ko Samui?

    Departing from Seattle to Ko Samui will take you 25h 50m. Seattle and Ko Samui are separated by a distance of 7715 mi. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

  • What are the cheapest airlines flying from Seattle to Ko Samui round-trip?

    Singapore Airlines, at $859, was found to be the cheapest airline from Seattle to Ko Samui. An alternate airline flying to your destination would be EVA Air.

  • Can I find deals for flights from Seattle to Ko Samui that include hotel bookings?

    Yes. In addition to deals on Seattle to Ko Samui flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Seattle to Ko Samui?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Seattle to Ko Samui.

  • Can I find deals for business class flights from Seattle to Ko Samui?

    Yes. Cheapflights offers flight deals from Seattle to Ko Samui by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

See more FAQs

Traveling to a place near Ko Samui?

Book flights to Ko Samui if you plan to visit one of these locations
Ko Tao
Ko Pha Ngan

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Top 2 airlines flying from Seattle to Ko Samui

Discover the top 2 airlines that operate flights from Seattle to Ko Samui. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated November 26, 2025.
AirlineCheapestAverageFlexibilityOn-time
Singapore AirlinesCheapest$859Average$1,066FlexibilityNo cancel feeOn-time81%
EVA AirCheapest$999Average$1,258FlexibilityNo cancel feeOn-time74%

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