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Ko Samui

$580+ Cheap flights from Washington, D.C. (WAS) 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 11/27. Fares are subject to change and may not be available on all flights or dates of travel.
WAS — USM
Aug 23 — Aug 301
Sat 8/23
Sat 8/30
1 adult, Economy
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Cheap flight deals from Washington, D.C. to Ko Samui

Discover tips and strategies to find the most affordable flight options for your journey from Washington, D.C. (WAS) 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 August 18, 2025.

Round-trip from

$1,160
(SmartFares)

One-way from

$580
(Turkish Airlines)
From Washington, D.C. (WAS) to Ko Samui
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One-way flight from Washington, D.C. (WAS) to Ko Samui
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Find flight deals from Washington, D.C. to Ko Samui

Cheapest flights from Washington, D.C. to Ko Samui
Explore the most affordable flight options available from Washington, D.C. to Ko Samui. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 18, 2025.

This SmartFares deal was found by Cheapflights users on 8/17. 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 SmartFares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/291:30 pmIAD - USM
2 stops29h 40mMultiple Airlines
Sun 1/257:10 pmUSM - IAD
2 stops28h 35mMultiple Airlines
Deal found 8/17$1,160
This Trip.com deal was found by Cheapflights users on 8/16. 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 11/299:10 pmIAD - USM
2 stops36h 10mMultiple Airlines
Mon 1/267:00 amUSM - IAD
2 stops48h 15mMultiple Airlines
Deal found 8/16$1,175
This FlightHub deal was found by Cheapflights users on 8/17. 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.
Sat 11/291:30 pmIAD - USM
2 stops31h 10mTurkish Airlines
Mon 1/2610:00 amUSM - IAD
2 stops45h 15mTurkish Airlines
Deal found 8/17$1,180
This Trip.com deal was found by Cheapflights users on 8/16. 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.
Tue 9/3010:05 pmIAD - USM
2 stops35h 45mMultiple Airlines
Tue 10/78:45 amUSM - IAD
2 stops42h 25mMultiple Airlines
Deal found 8/16$1,221
This KAYAK deal was found by Cheapflights users on 8/17. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/291:30 pmIAD - USM
2 stops31h 10mTurkish Airlines
Fri 1/307:55 amUSM - IAD
2 stops39h 50mTurkish Airlines
Deal found 8/17$1,258
This KAYAK deal was found by Cheapflights users on 8/17. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/2710:10 pmIAD - USM
2 stops33h 05mTurkish Airlines
Mon 11/107:00 pmUSM - IAD
2 stops52h 45mTurkish Airlines
Deal found 8/17$1,274
This FlightHub deal was found by Cheapflights users on 8/17. 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.
Wed 10/19:00 pmIAD - USM
2 stops26h 30mQatar Airways
Fri 10/315:05 pmUSM - IAD
2 stops34h 50mQatar Airways
Deal found 8/17$1,311
This FlightHub deal was found by Cheapflights users on 8/17. 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.
Fri 9/59:00 pmIAD - USM
2 stops32h 55mMultiple Airlines
Sat 9/135:35 pmUSM - IAD
2 stops26h 05mMultiple Airlines
Deal found 8/17$1,377
This Qatar Airways deal was found by Cheapflights users on 8/16. 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 Qatar Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/259:00 pmIAD - USM
2 stops29h 55mQatar Airways
Mon 9/293:25 pmUSM - IAD
2 stops35h 15mQatar Airways
Deal found 8/16$1,432
This Mytrip deal was found by Cheapflights users on 8/16. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/304:27 pmBWI - USM
3 stops31h 43mMultiple Airlines
Tue 10/78:45 amUSM - BWI
3 stops36h 43mMultiple Airlines
Deal found 8/16$1,599
This Cathay Pacific deal was found by Cheapflights users on 8/17. 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 Cathay Pacific is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/187:33 pmDCA - USM
2 stops36h 02mCathay Pacific
Mon 9/2210:55 amUSM - DCA
2 stops32h 04mCathay Pacific
Deal found 8/17$1,828
This Ovago deal was found by Cheapflights users on 8/16. 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 Ovago is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/67:35 pmDCA - USM
2 stops36h 00mCathay Pacific
Sat 9/1310:55 amUSM - DCA
2 stops32h 04mCathay Pacific
Deal found 8/16$1,845

Cheapflights Fare Finder

 
Customize your flight search to find flights from Washington, D.C. 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 August 18, 2025.
Use the filters below to find and compare flights from Washington, D.C. to Ko Samui that are best for you.

Fly from

Washington, D.C.

Fly to

Ko Samui

Route

Depart

Return

Price

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Tue 9/30

10:05 pm-8:50 pm

2 stops35h 45m

Ko Samui

Tue 10/7

8:45 am-4:10 pm

2 stops42h 25m

$1,221

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Mon 10/27

10:10 pm-6:15 pm

2 stops33h 05m

Ko Samui

Mon 11/10

7:00 pm-11:45 am

2 stops52h 45m

$1,274

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Wed 10/1

9:00 pm-11:55 am

2 stops27h 55m

Ko Samui

Fri 10/31

5:05 pm-4:55 pm

2 stops34h 50m

$1,311

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Thu 9/25

1:30 pm-8:35 am

2 stops32h 05m

Ko Samui

Mon 9/29

7:00 pm-11:45 am

2 stops27h 45m

$1,348

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Sat 9/6

9:00 pm-10:10 am

2 stops26h 10m

Ko Samui

Sat 9/13

2:30 pm-8:40 am

2 stops29h 10m

$1,377

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Fri 9/5

9:00 pm-4:55 pm

2 stops32h 55m

Ko Samui

Sat 9/13

5:35 pm-8:40 am

2 stops26h 05m

$1,377

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Thu 9/25

9:00 pm-1:55 pm

2 stops29h 55m

Ko Samui

Mon 9/29

3:25 pm-3:40 pm

2 stops35h 15m

$1,432

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Wed 10/1

9:20 pm-4:35 pm

3 stops32h 15m

Ko Samui

Fri 10/31

8:30 pm-8:05 pm

3 stops34h 35m

$1,447

BaltimoreKo Samui

BWI - USM

BWIUSM

Baltimore/Washington

Tue 9/30

4:27 pm-11:10 am

3 stops31h 43m

Ko Samui

Tue 10/7

8:45 am-10:28 am

3 stops36h 43m

$1,599

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Thu 9/18

7:33 pm-6:35 pm

2 stops36h 02m

Ko Samui

Mon 9/22

10:55 am-7:59 am

2 stops32h 04m

$1,828

Flights are sorted by cheapest round-trip flights first.

Deals found on 8/16

Showing 1-10 of 22 results
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Best time to book a flight from Washington, D.C. to Ko Samui

Have a flexible travel schedule? Discover the best time to fly to Ko Samui from Washington, D.C. 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 Washington, D.C. to Ko Samui

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

Find hourly flight availability from Washington, D.C. 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 August 18, 2025.

One of the essential ways to save on airfare from Washington, D.C. to Ko Samui is to remain as flexible as possible. Flights that are at noon tend to be the most expensive. A flight in the evening could potentially save you up to 29% on airfare.

What is the cheapest day to fly from Washington, D.C. to Ko Samui?

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

Travelers seeking maximum savings on their Washington, D.C. to Ko Samui flight should consider departing on Tuesday mornings 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.

Related info for your journey

Find useful and relevant information for your journey from Washington, D.C. to Ko Samui. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly into for flights to Ko Samui from Washington, D.C.?

    For a flight from Washington, D.C. to Ko Samui, you will be flying into Ko Samui. Ko Samui (USM) is just 2.1 mi from the center of the city. Ko Samui is the only Ko Samui airport and it handles 0 inbound flights from Washington, D.C. per day. 0 airlines have flights to Ko Samui from Washington, D.C. on a regular basis.

  • How long is the flight from Washington, D.C. to Ko Samui?

    Turkish Airlines, Qatar Airways, and Cathay Pacific can get you from Washington, D.C. to Ko Samui in just under 27h 55m. Your travel time can differ by up to 8h 07m. There are 9076 mi between Washington, D.C. and Ko Samui. Both multi-stop and nonstop flights can be found to your destination and back.

  • What are the most popular routes from Washington, D.C. to Ko Samui?

    The most popular flight routes from Washington, D.C. to Ko Samui are Washington, D.C. Dulles Intl - Ko Samui, Baltimore/Washington - Ko Samui and Washington, D.C. Reagan-National - Ko Samui.

  • Can I find deals for flights from Washington, D.C. to Ko Samui that include hotel bookings?

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

  • How can I find direct flights from Washington, D.C. to Ko Samui?

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

  • Can I find deals for business class flights from Washington, D.C. to Ko Samui?

    Yes. Cheapflights offers flight deals from Washington, D.C. 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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