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Cheap flights from Washington to Ko Samui from $528

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 11/6. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
1 adult
1 adult, Economy, 0 bags

Find the cheapest flights from Washington to Ko Samui

Cheap round-trip flights

Enter your travel dates to find the best prices.
Multiple Airlines Logo
3:30 pm - 9:10 pm
PDX
-
USM
39h 40m
2 stops
Multiple Airlines Logo
4:25 pm - 9:31 am
USM
-
PDX
31h 06m
2 stops
$1,301Multiple Airlines
Tue, Sep 8 - Sat, Sep 26
EVA Air Logo
2:10 am - 2:45 pm
SEA
-
USM
22h 35m
2 stops
EVA Air Logo
9:15 am - 7:50 pm
USM
-
SEA
24h 35m
2 stops
$1,335EVA Air
Sun, Aug 23 - Mon, Aug 31
Multiple Airlines Logo
7:45 pm - 6:15 pm
PDX
-
USM
32h 30m
2 stops
Multiple Airlines Logo
7:10 pm - 2:51 pm
USM
-
PDX
33h 41m
3 stops
$1,338Multiple Airlines
Tue, Jul 14 - Mon, Sep 14
Multiple Airlines Logo
7:20 pm - 6:15 pm
SEA
-
USM
32h 55m
2 stops
Multiple Airlines Logo
9:25 pm - 10:07 am
USM
-
SEA
26h 42m
2 stops
$1,367Multiple Airlines
Sun, Jul 19 - Sun, Jul 26
Multiple Airlines Logo
5:41 pm - 1:45 pm
PDX
-
USM
30h 04m
3 stops
Multiple Airlines Logo
2:00 pm - 10:01 pm
USM
-
PDX
22h 01m
3 stops
$1,385Multiple Airlines
Tue, Sep 8 - Sat, Sep 26
Multiple Airlines Logo
7:00 am - 7:45 am
SEA
-
USM
34h 45m
3 stops
Multiple Airlines Logo
7:50 am - 7:45 pm
USM
-
SEA
25h 55m
2 stops
$1,404Multiple Airlines
Wed, Jul 15 - Sat, Jul 18
Multiple Airlines Logo
4:30 pm - 8:45 pm
SEA
-
USM
38h 15m
2 stops
Multiple Airlines Logo
10:00 am - 2:25 pm
USM
-
SEA
42h 25m
2 stops
$1,455Multiple Airlines
Fri, Jul 10 - Fri, Jul 17
Multiple Airlines Logo
3:00 pm - 7:45 am
SEA
-
USM
26h 45m
2 stops
Multiple Airlines Logo
7:50 am - 7:45 pm
USM
-
SEA
25h 55m
2 stops
$1,457Multiple Airlines
Wed, Jul 15 - Sat, Jul 18
Multiple Airlines Logo
7:45 pm - 11:05 am
PDX
-
USM
25h 20m
2 stops
Multiple Airlines Logo
10:05 am - 7:50 pm
USM
-
PDX
23h 45m
3 stops
$1,461Multiple Airlines
Mon, Jul 13 - Sun, Sep 13
EVA Air Logo
2:10 am - 4:35 pm
SEA
-
USM
24h 25m
2 stops
EVA Air Logo
8:45 am - 7:10 pm
USM
-
SEA
24h 25m
2 stops
$1,623EVA Air
Tue, Jul 28 - Thu, Aug 6

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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
EVA Air
Aug 23
SEA2:10 amSeattle/Tacoma Intl
22h 35m
2 stops
USM2:45 pmKo Samui
Aug 31
USM9:15 amKo Samui
24h 35m
2 stops
SEA7:50 pmSeattle/Tacoma Intl
$1,335
EVA Air
Jul 28
SEA2:10 amSeattle/Tacoma Intl
24h 25m
2 stops
USM4:35 pmKo Samui
Aug 6
USM8:45 amKo Samui
24h 25m
2 stops
SEA7:10 pmSeattle/Tacoma Intl
$1,623
EVA Air
Jul 27
SEA2:10 amSeattle/Tacoma Intl
23h 10m
2 stops
USM3:20 pmKo Samui
Aug 6
USM8:45 amKo Samui
24h 25m
2 stops
SEA7:10 pmSeattle/Tacoma Intl
$1,639

Cathay Pacific flights from State of Washington to Ko Samui

Our best Cathay Pacific deals on State of Washington to Ko Samui flight tickets
Cathay Pacific
Aug 24
SEA7:56 pmSeattle/Tacoma Intl
33h 44m
2 stops
USM7:40 pmKo Samui
Aug 31
USM11:55 amKo Samui
36h 25m
1 stop
SEA10:20 amSeattle/Tacoma Intl
$1,673
Cathay Pacific
Aug 24
SEA1:13 pmSeattle/Tacoma Intl
40h 27m
2 stops
USM7:40 pmKo Samui
Aug 31
USM11:55 amKo Samui
36h 25m
1 stop
SEA10:20 amSeattle/Tacoma Intl
$1,679
Cathay Pacific
Jul 28
SEA7:56 pmSeattle/Tacoma Intl
33h 44m
2 stops
USM7:40 pmKo Samui
Aug 7
USM11:55 amKo Samui
36h 25m
1 stop
SEA10:20 amSeattle/Tacoma Intl
$2,174

momondo Fare Finder

 
Customize your flight search to find flights from State of Washington 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, momondo users made 832,500 searches. Data last updated June 17, 2026.
Use the filters below to find and compare flights from Washington to Ko Samui that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

PortlandKo Samui

PDX - USM

PDXUSM

Portland

Tue 9/8

3:30 pm-9:10 pm

2 stops39h 40m

Ko Samui

Sat 9/26

4:25 pm-9:31 am

2 stops31h 06m

$1,301
Quickest round-trip

SeattleKo Samui

SEA - USM

SEAUSM

Seattle/Tacoma Intl

Sun 8/23

2:10 am-2:45 pm

2 stops22h 35m

Ko Samui

Mon 8/31

9:15 am-7:50 pm

2 stops24h 35m

$1,335

PortlandKo Samui

PDX - USM

PDXUSM

Portland

Tue 7/14

7:45 pm-6:15 pm

2 stops32h 30m

Ko Samui

Mon 9/14

7:10 pm-2:51 pm

3 stops33h 41m

$1,338

SeattleKo Samui

SEA - USM

SEAUSM

Seattle/Tacoma Intl

Sun 7/19

7:20 pm-6:15 pm

2 stops32h 55m

Ko Samui

Sun 7/26

9:25 pm-10:07 am

2 stops26h 42m

$1,367

PortlandKo Samui

PDX - USM

PDXUSM

Portland

Tue 9/8

5:41 pm-1:45 pm

3 stops30h 04m

Ko Samui

Sat 9/26

2:00 pm-10:01 pm

3 stops22h 01m

$1,385

SeattleKo Samui

SEA - USM

SEAUSM

Seattle/Tacoma Intl

Wed 7/15

7:00 am-7:45 am

3 stops34h 45m

Ko Samui

Sat 7/18

7:50 am-7:45 pm

2 stops25h 55m

$1,404

SeattleKo Samui

SEA - USM

SEAUSM

Seattle/Tacoma Intl

Fri 7/10

4:30 pm-8:45 pm

2 stops38h 15m

Ko Samui

Fri 7/17

10:00 am-2:25 pm

2 stops42h 25m

$1,455

SeattleKo Samui

SEA - USM

SEAUSM

Seattle/Tacoma Intl

Wed 7/15

3:00 pm-7:45 am

2 stops26h 45m

Ko Samui

Sat 7/18

7:50 am-7:45 pm

2 stops25h 55m

$1,457

PortlandKo Samui

PDX - USM

PDXUSM

Portland

Mon 7/13

7:45 pm-11:05 am

2 stops25h 20m

Ko Samui

Sun 9/13

10:05 am-7:50 pm

3 stops23h 45m

$1,461

SeattleKo Samui

SEA - USM

SEAUSM

Seattle/Tacoma Intl

Tue 7/28

2:10 am-4:35 pm

2 stops24h 25m

Ko Samui

Thu 8/6

8:45 am-7:10 pm

2 stops24h 25m

$1,623

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first
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See travel insights to Ko Samui from

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

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

You could potentially save up to 23% 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

25h 15m

Direct flights

None
The fastest flight from State of Washington to Ko Samui takes 25h 15m
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.
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Frequently asked questions about flying 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 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.

Traveling to a place near Ko Samui?

Book flights to Ko Samui if you plan to visit one of these locations
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.

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