What is the cheapest airline that flies from Washington to Ko Samui?

EVA Air and Singapore Airlines are the most popular carriers operating from Washington to Ko Samui

When did momondo last update prices for flights from Washington to Ko Samui Airport?

Prices for flights from Washington to Ko Samui Airport were last updated today.

How many operators does momondo search for flights from Washington to Ko Samui Airport?

As of March 2026, there is 1 operator available to choose from for flights from Washington to Ko Samui Airport.

How old do you have to be to fly from Washington to Ko Samui Airport?

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 Washington to Ko Samui Airport.

What documentation or ID do you need to fly to Ko Samui Airport?

The travel and health documents you'll need for your trip to Ko Samui Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Ko Samui Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

$614 Cheap Flights from Washington to Ko Samui in 2026

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Find the cheapest flights from Washington to Ko Samui

Round-trip

One-way

Cheap round-trip flights

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2:10 am - 2:45 pm

SEA

USM

22h 35m

2 stops

9:00 pm - 7:40 pm

USM

SEA

36h 40m

2 stops

$991EVA Air

Ahad, Ogos 30 - Ahad, Sep 6

1:30 am - 3:45 pm

SEA

USM

24h 15m

2 stops

9:15 am - 7:40 pm

USM

SEA

24h 25m

2 stops

$1,052EVA Air

Rabu, Sep 16 - Isnin, Sep 21

1:15 am - 2:45 pm

SEA

USM

23h 30m

2 stops

10:05 am - 7:15 pm

USM

SEA

23h 10m

2 stops

$1,131Multiple Airlines

Isnin, Mei 4 - Selasa, Mei 12

10:15 am - 5:20 pm

SEA

USM

41h 05m

1 stop

8:40 am - 8:45 am

USM

SEA

38h 05m

1 stop

$1,187Singapore Airlines

Khamis, Sep 17 - Isnin, Sep 21

7:00 am - 7:10 am

PDX

USM

34h 10m

3 stops

8:50 pm - 4:22 pm

USM

PDX

33h 32m

3 stops

$1,191Multiple Airlines

Isnin, Mei 4 - Isnin, Mei 11

10:15 am - 5:20 pm

SEA

USM

41h 05m

1 stop

11:05 am - 8:45 am

USM

SEA

35h 40m

1 stop

$1,243Singapore Airlines

Khamis, Sep 17 - Isnin, Sep 21

4:25 pm - 6:00 pm

SEA

USM

35h 35m

2 stops

5:55 pm - 12:45 pm

USM

SEA

32h 50m

2 stops

$1,307Qatar Airways

Ahad, Apr 5 - Selasa, Apr 14

4:25 pm - 4:55 pm

SEA

USM

34h 30m

2 stops

5:55 pm - 12:45 pm

USM

SEA

32h 50m

2 stops

$1,341Qatar Airways

Isnin, Apr 6 - Rabu, Apr 15

11:47 pm - 7:40 pm

PDX

USM

53h 53m

2 stops

11:55 am - 9:35 pm

USM

PDX

23h 40m

2 stops

$1,658Cathay Pacific

Ahad, Apr 12 - Ahad, Apr 19

11:30 pm - 7:40 pm

PDX

USM

54h 10m

2 stops

11:55 am - 9:35 pm

USM

PDX

23h 40m

2 stops

$1,659Cathay Pacific

Isnin, Apr 6 - Rabu, Apr 15

EVA Air flights from State of Washington to Ko Samui

Our best EVA Air deals on State of Washington to Ko Samui flight tickets

EVA Air

Aug 30

SEA2:10 amSeattle/Tacoma Intl

22h 35m

2 stops

USM2:45 pmKo Samui

Sep 6

USM9:00 pmKo Samui

36h 40m

2 stops

SEA7:40 pmSeattle/Tacoma Intl

$991

EVA Air

Sep 16

SEA1:30 amSeattle/Tacoma Intl

24h 15m

2 stops

USM3:45 pmKo Samui

Sep 21

USM9:15 amKo Samui

24h 25m

2 stops

SEA7:40 pmSeattle/Tacoma Intl

$1,052

EVA Air

Apr 19

SEA1:30 amSeattle/Tacoma Intl

22h 15m

2 stops

USM1:45 pmKo Samui

Apr 27

USM8:50 pmKo Samui

36h 00m

2 stops

SEA6:50 pmSeattle/Tacoma Intl

$1,181

Singapore Airlines flights from State of Washington to Ko Samui

Our best Singapore Airlines deals on State of Washington to Ko Samui flight tickets

Singapore Airlines

Sep 17

SEA10:15 amSeattle/Tacoma Intl

41h 05m

1 stop

USM5:20 pmKo Samui

Sep 21

USM8:40 amKo Samui

38h 05m

1 stop

SEA8:45 amSeattle/Tacoma Intl

$1,187

Singapore Airlines

Sep 17

SEA10:15 amSeattle/Tacoma Intl

41h 05m

1 stop

USM5:20 pmKo Samui

Sep 21

USM11:05 amKo Samui

35h 40m

1 stop

SEA8:45 amSeattle/Tacoma Intl

$1,243

Singapore Airlines

Sep 8

SEA10:15 amSeattle/Tacoma Intl

31h 30m

1 stop

USM7:45 amKo Samui

Sep 10

USM6:15 pmKo Samui

28h 30m

1 stop

SEA8:45 amSeattle/Tacoma Intl

$1,349

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

SeattleKo Samui

SEA - USM

SEAUSM

Seattle/Tacoma Intl

Ahad 8/30

2:10 am-2:45 pm

2 stops22h 35m

Ko Samui

Ahad 9/6

9:00 pm-7:40 pm

2 stops36h 40m

$991

SeattleKo Samui

SEA - USM

SEAUSM

Seattle/Tacoma Intl

Rabu 9/16

1:30 am-3:45 pm

2 stops24h 15m

Ko Samui

Isnin 9/21

9:15 am-7:40 pm

2 stops24h 25m

$1,052

Quickest round-trip

SeattleKo Samui

SEA - USM

SEAUSM

Seattle/Tacoma Intl

Isnin 5/4

1:15 am-2:45 pm

2 stops23h 30m

Ko Samui

Selasa 5/12

10:05 am-7:15 pm

2 stops23h 10m

$1,131

SeattleKo Samui

SEA - USM

SEAUSM

Seattle/Tacoma Intl

Khamis 9/17

10:15 am-5:20 pm

1 stop41h 05m

Ko Samui

Isnin 9/21

8:40 am-8:45 am

1 stop38h 05m

$1,187

PortlandKo Samui

PDX - USM

PDXUSM

Portland

Isnin 5/4

7:00 am-7:10 am

3 stops34h 10m

Ko Samui

Isnin 5/11

8:50 pm-4:22 pm

3 stops33h 32m

$1,191

SeattleKo Samui

SEA - USM

SEAUSM

Seattle/Tacoma Intl

Khamis 9/17

10:15 am-5:20 pm

1 stop41h 05m

Ko Samui

Isnin 9/21

11:05 am-8:45 am

1 stop35h 40m

$1,243

SeattleKo Samui

SEA - USM

SEAUSM

Seattle/Tacoma Intl

Ahad 4/5

4:25 pm-6:00 pm

2 stops35h 35m

Ko Samui

Selasa 4/14

5:55 pm-12:45 pm

2 stops32h 50m

$1,307

SeattleKo Samui

SEA - USM

SEAUSM

Seattle/Tacoma Intl

Isnin 4/6

4:25 pm-4:55 pm

2 stops34h 30m

Ko Samui

Rabu 4/15

5:55 pm-12:45 pm

2 stops32h 50m

$1,341

PortlandKo Samui

PDX - USM

PDXUSM

Portland

Ahad 4/12

11:47 pm-7:40 pm

2 stops53h 53m

Ko Samui

Ahad 4/19

11:55 am-9:35 pm

2 stops23h 40m

$1,658

PortlandKo Samui

PDX - USM

PDXUSM

Portland

Isnin 4/6

11:30 pm-7:40 pm

2 stops54h 10m

Ko Samui

Rabu 4/15

11:55 am-9:35 pm

2 stops23h 40m

$1,659

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 13 resultsSorted by cheapest first

How to get the cheapest flight ticket from State of Washington to Ko Samui

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 day to depart on your flight to Ko Samui?

Our data shows that Tuesday is the least expensive day to fly to Ko Samui. Tickets to fly out on this day can be as low as $275. Flights from State of Washington to Ko Samui on a Sunday will generally be more expensive and average around $548. Keep in mind that these prices on both days could fluctuate depending on the season and the demand.

What is the cheapest time of day to depart on your flight to Ko Samui?

Our data shows that the cheapest State of Washington to Ko Samui flights are usually those with departure times in the afternoon. Our users have found flights to Ko Samui in the afternoon for as low as $304. In the evening is when there is more demand to fly to Ko Samui, so prices are often more expensive at around $454 per ticket.

Can stopping save me money on State of Washington to Ko Samui flights?

You could potentially save up to 1% on your flight if you consider stops on a State of Washington to Ko Samui flight.

Cheap State of Washington to Ko Samui flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from State of Washington to Ko Samui

Fastest flight time	28h 05m
Direct flights	None

The fastest flight from State of Washington to Ko Samui takes 28h 05m

There are no direct flights from State of Washington to Ko Samui. There are no popular flight routes from State of Washington to Ko Samui.

Search flight deals

When did momondo last update prices for flights from Washington to Ko Samui Airport?
Prices for flights from Washington to Ko Samui Airport were last updated today.
How many operators does momondo search for flights from Washington to Ko Samui Airport?
As of March 2026, there is 1 operator available to choose from for flights from Washington to Ko Samui Airport.
How old do you have to be to fly from Washington to Ko Samui Airport?
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 Washington to Ko Samui Airport.
What documentation or ID do you need to fly to Ko Samui Airport?
The travel and health documents you'll need for your trip to Ko Samui Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Ko Samui Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

Best airlines flying from State of Washington to Ko Samui

Compare and see reviews for airlines that fly from State of Washington to Ko Samui with momondo

Airline	Rating	Free Cancellation	Price
Singapore Airlines	PriceFrom $859	Free Cancellation	Rating 8.2 1,484 reviews		Search Singapore Airlines flights

Ko Pha Ngan

Ko Tao

Khanom

Why use momondo?

Why should I use momondo to find a flight deal from Washington to Ko Samui?

momondo collates all your flight options in one place and lets you filter them to find the perfect flight from Washington to Ko Samui. momondo saves you time and could save you money on your trip.

Can I find flights from Washington to Ko Samui with flexible booking policies on momondo?

Yes. All flights to Ko Samui from Washington on momondo can be compared and filtered by various policies on offer, including flexible booking.

How can momondo help me find flights from Washington to Ko Samui?

Once you have performed a search in the form on the page, momondo provides useful filters and insights. We can show you the cheapest days and times to fly as well as help filter your options to help you make an informed choice when booking flights to Ko Samui from Washington.

I’m not ready to book a flight from Washington to Ko Samui right now. Can momondo alert me if prices change?

Price alerts on flights to Ko Samui from Washington are quick and easy to set up on momondo. Simply perform a search and select the price alert feature. It is as simple as that.

An easier way to manage your Ko Samui trip

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Khamis 4/23

Khamis 4/30

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Cheap flights from Washington to Ko Samui from $661

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Washington to Ko Samui departing on 5/15. 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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Big names and deals

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Filter for what you want

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Find the cheapest flights from Washington to Ko Samui

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EVA Air flights from State of Washington to Ko Samui

Our best EVA Air deals on State of Washington to Ko Samui flight tickets

Singapore Airlines flights from State of Washington to Ko Samui

Our best Singapore Airlines deals on State of Washington to Ko Samui flight tickets

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How to get the cheapest flight ticket from State of Washington to Ko Samui

What is the cheapest day to depart on your flight to Ko Samui?

What is the cheapest time of day to depart on your flight to Ko Samui?

Can stopping save me money on State of Washington to Ko Samui flights?

What is the cheapest airline that flies from Washington to Ko Samui?

Cheap State of Washington to Ko Samui flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from State of Washington to Ko Samui

Fastest flight time

Direct flights

Best airlines flying from State of Washington to Ko Samui

Compare and see reviews for airlines that fly from State of Washington to Ko Samui with momondo

Traveling to a place near Ko Samui?

Why use momondo?

An easier way to manage your Ko Samui 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.

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Airlines are sorted and displayed according to clicks in the past 7 days on momondo

Cabin classes currently available on flights to Ko Samui

List of cabin classes available on flights landing in Ko Samui. Availability may vary depending on flight origin and airline.

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