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Ko Samui

$711+ 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 11/30. Fares are subject to change and may not be available on all flights or dates of travel.
WAS — USM
Nov 15 — Nov 221
Sat 11/15
Sat 11/22
1 adult, Economy
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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 October 16, 2025.

This oojo deal was found by Cheapflights users on 10/16. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/299:10 pmIAD - USM
2 stops23h 30mMultiple Airlines
Sun 1/256:30 pmUSM - IAD
2 stops33h 00mMultiple Airlines
Deal found 10/16$1,113
This Vliegwinkel deal was found by Cheapflights users on 10/16. 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 Vliegwinkel is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/19:10 pmIAD - USM
2 stops23h 30mMultiple Airlines
Mon 12/88:50 amUSM - IAD
2 stops66h 40mMultiple Airlines
Deal found 10/16$1,171
This oojo deal was found by Cheapflights users on 10/16. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/299:10 pmIAD - USM
2 stops23h 30mEtihad Airways
Mon 1/268:50 amUSM - IAD
2 stops66h 40mEtihad Airways
Deal found 10/16$1,181
This oojo deal was found by Cheapflights users on 10/16. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 11/309:10 pmIAD - USM
2 stops27h 55mEtihad Airways
Sun 12/78:50 amUSM - IAD
2 stops66h 40mEtihad Airways
Deal found 10/16$1,267
This Mytrip deal was found by Cheapflights users on 10/16. 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.
Sun 11/301:30 pmIAD - USM
2 stops30h 35mMultiple Airlines
Sun 12/76:15 pmUSM - IAD
3 stops33h 15mMultiple Airlines
Deal found 10/16$1,322
This KAYAK deal was found by Cheapflights users on 10/15. 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 stops30h 35mTurkish Airlines
Fri 1/301:25 pmUSM - IAD
2 stops34h 20mTurkish Airlines
Deal found 10/15$1,450
This Gotogate deal was found by Cheapflights users on 10/16. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 11/306:00 amDCA - USM
3 stops37h 45mMultiple Airlines
Sun 12/74:30 pmUSM - DCA
3 stops42h 05mMultiple Airlines
Deal found 10/16$1,469
This oojo deal was found by Cheapflights users on 10/15. 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 11/295:59 amDCA - USM
2 stops49h 36mCathay Pacific
Sat 12/611:40 amUSM - DCA
2 stops47h 19mCathay Pacific
Deal found 10/15$1,501
This Ovago deal was found by Cheapflights users on 10/15. 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 11/295:59 amDCA - USM
2 stops25h 36mMultiple Airlines
Sat 12/67:35 pmUSM - DCA
3 stops59h 19mMultiple Airlines
Deal found 10/15$1,597
This oojo deal was found by Cheapflights users on 10/16. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 11/3012:59 pmDCA - USM
2 stops42h 36mCathay Pacific
Sun 12/711:40 amUSM - DCA
2 stops48h 16mCathay Pacific
Deal found 10/16$1,777
This Cathay Pacific deal was found by Cheapflights users on 10/16. 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 Cathay Pacific is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/12:52 pmDCA - USM
2 stops40h 43mMultiple Airlines
Mon 12/811:40 amUSM - DCA
2 stops44h 20mMultiple Airlines
Deal found 10/16$1,987
This Cathay Pacific deal was found by Cheapflights users on 10/14. 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 10/3012:31 pmDCA - USM
2 stops44h 04mCathay Pacific
Mon 11/311:40 amUSM - DCA
2 stops43h 04mCathay Pacific
Deal found 10/14$2,036

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 October 16, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$1,033
(FlightHub)

One-way from

$711
(KAYAK)
Provider with most accurate pricing for Washington, D.C. (WAS)-Ko Samui flight deals.
Search Deals
Provider most trusted by Cheapflights users for Washington, D.C. (WAS)-Ko Samui flights.
Search Deals
From Washington, D.C. (WAS) to Ko Samui
Search Deals
One-way flight from Washington, D.C. (WAS) to Ko Samui
Search Deals

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 October 16, 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

Sat 11/29

9:10 pm-8:40 am

2 stops23h 30m

Ko Samui

Sun 1/25

6:30 pm-3:30 pm

2 stops33h 00m

$1,113

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Mon 12/1

9:10 pm-8:40 am

2 stops23h 30m

Ko Samui

Mon 12/8

8:50 am-3:30 pm

2 stops66h 40m

$1,171

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Sat 11/29

9:10 pm-8:40 am

2 stops23h 30m

Ko Samui

Mon 1/26

8:50 am-3:30 pm

2 stops66h 40m

$1,181

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Sun 11/30

1:30 pm-8:05 am

2 stops30h 35m

Ko Samui

Sun 12/7

6:15 pm-3:30 pm

3 stops33h 15m

$1,322

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Sat 11/29

1:30 pm-8:05 am

2 stops30h 35m

Ko Samui

Fri 1/30

1:25 pm-11:45 am

2 stops34h 20m

$1,450

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Wed 3/4

5:30 pm-7:35 pm

2 stops38h 05m

Ko Samui

Fri 3/13

11:40 am-3:56 pm

2 stops39h 16m

$1,451

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Sun 11/30

6:00 am-7:45 am

3 stops37h 45m

Ko Samui

Sun 12/7

4:30 pm-10:35 pm

3 stops42h 05m

$1,469

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Sat 11/29

5:59 am-7:35 pm

2 stops49h 36m

Ko Samui

Sat 12/6

11:40 am-10:59 pm

2 stops47h 19m

$1,501

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Sat 11/29

5:59 am-7:35 pm

2 stops25h 36m

Ko Samui

Sat 12/6

7:35 pm-6:54 pm

3 stops59h 19m

$1,597

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Sun 11/30

12:59 pm-7:35 pm

2 stops42h 36m

Ko Samui

Sun 12/7

11:40 am-11:56 pm

2 stops48h 16m

$1,777

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/15

Showing 1-10 of 23 results
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Compare providers for flights from Washington, D.C. 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 Washington, D.C. to Ko Samui in October.
ProviderPrice AccuracyTrust Score*
FlightHubPrice Accuracy3 starsTrust Score*3 stars
OvagoPrice Accuracy2 starsTrust Score*2 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
AranGrantPrice 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 Washington, D.C.-Ko Samui flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Washington, D.C.-Ko Samui flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Washington, D.C.-Ko Samui flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Washington, D.C.-Ko Samui flights, Cheapflights users trust FlightHub the most. FlightHub 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 Washington, D.C.-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 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 October 16, 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 37% 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 Monday at noon when fares are most often at their lowest. Sunday at noon 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?

    Etihad Airways, Cathay Pacific, and British Airways can get you from Washington, D.C. to Ko Samui in just under 23h 30m. Your travel time can differ by up to 34h 10m. 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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