HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Ko Samui

$710+ 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
Dec 6 — Dec 131
Sat 12/6
Sat 12/13
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Washington, D.C. to Ko Samui with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

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 November 6, 2025.

This IEagle deal was found by Cheapflights users on 11/5. 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 IEagle is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/128:05 pmIAD - USM
2 stops27h 45mMultiple Airlines
Tue 11/255:40 pmUSM - IAD
2 stops26h 40mMultiple Airlines
Deal found 11/5$1,218
This oojo deal was found by Cheapflights users on 11/6. 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 11/291:30 pmIAD - USM
2 stops40h 45mMultiple Airlines
Sun 1/259:10 pmUSM - IAD
2 stops34h 10mMultiple Airlines
Deal found 11/6$1,302
This oojo deal was found by Cheapflights users on 11/6. 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 11/291:30 pmIAD - USM
2 stops40h 45mTurkish Airlines
Mon 1/261:25 pmUSM - IAD
2 stops34h 20mTurkish Airlines
Deal found 11/6$1,347
This oojo deal was found by Cheapflights users on 11/6. 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.
Wed 11/122:52 pmDCA - USM
2 stops40h 43mCathay Pacific
Tue 11/2511:40 amUSM - DCA
2 stops45h 04mCathay Pacific
Deal found 11/6$1,387
This oojo deal was found by Cheapflights users on 11/6. 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.
Thu 11/139:45 amDCA - USM
2 stops45h 50mCathay Pacific
Thu 11/2711:40 amUSM - DCA
2 stops45h 04mCathay Pacific
Deal found 11/6$1,400
This Cathay Pacific deal was found by Cheapflights users on 11/5. 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 11/134:59 pmDCA - USM
2 stops38h 36mMultiple Airlines
Thu 11/2711:40 amUSM - DCA
2 stops45h 04mMultiple Airlines
Deal found 11/5$1,416
This Cathay Pacific deal was found by Cheapflights users on 11/5. 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 11/139:45 amDCA - USM
2 stops45h 50mCathay Pacific
Mon 11/1711:40 amUSM - DCA
2 stops43h 04mCathay Pacific
Deal found 11/5$1,441
This KAYAK deal was found by Cheapflights users on 11/4. 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 stops40h 45mTurkish Airlines
Fri 1/301:25 pmUSM - IAD
2 stops34h 20mTurkish Airlines
Deal found 11/4$1,474
This FlightHub deal was found by Cheapflights users on 11/6. 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.
Thu 11/138:05 pmIAD - USM
2 stops29h 45mQatar Airways
Thu 11/2710:00 amUSM - IAD
2 stops34h 20mQatar Airways
Deal found 11/6$1,608
This British Airways deal was found by Cheapflights users on 11/4. 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 British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/138:35 pmBWI - USM
2 stops57h 40mBritish Airways
Mon 11/171:25 pmUSM - BWI
2 stops41h 20mBritish Airways
Deal found 11/4$2,440
This British Airways deal was found by Cheapflights users on 11/6. 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 British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/138:35 pmBWI - USM
2 stops36h 30mBritish Airways
Thu 11/274:25 pmUSM - BWI
2 stops38h 20mBritish Airways
Deal found 11/6$2,495
This Ovago deal was found by Cheapflights users on 11/6. 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.
Wed 11/128:35 pmBWI - USM
2 stops33h 40mBritish Airways
Tue 11/254:25 pmUSM - BWI
2 stops38h 20mBritish Airways
Deal found 11/6$2,793

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 November 6, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$1,133
(oojo)

One-way from

$710
(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 November 6, 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

Mon 2/2

8:05 pm-9:20 am

2 stops25h 15m

Ko Samui

Tue 2/24

5:40 pm-8:20 am

2 stops26h 40m

$1,243

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Wed 2/4

8:05 pm-9:20 am

2 stops25h 15m

Ko Samui

Tue 2/24

5:40 pm-8:20 am

2 stops26h 40m

$1,243

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Sat 11/29

1:30 pm-6:15 pm

2 stops40h 45m

Ko Samui

Sun 1/25

9:10 pm-7:20 pm

2 stops34h 10m

$1,302

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Sat 11/29

1:30 pm-6:15 pm

2 stops40h 45m

Ko Samui

Mon 1/26

1:25 pm-11:45 am

2 stops34h 20m

$1,347

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Tue 2/3

8:05 pm-9:20 am

2 stops25h 15m

Ko Samui

Mon 2/23

3:05 pm-3:55 pm

2 stops36h 50m

$1,350

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Thu 2/5

1:30 pm-1:05 pm

2 stops35h 35m

Ko Samui

Tue 2/24

8:15 am-7:20 pm

2 stops47h 05m

$1,354

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Mon 2/2

8:05 pm-8:25 pm

2 stops36h 20m

Ko Samui

Wed 2/25

3:50 pm-3:55 pm

2 stops36h 05m

$1,387

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Sun 2/1

8:05 pm-6:55 pm

2 stops34h 50m

Ko Samui

Mon 2/23

3:05 pm-3:55 pm

2 stops36h 50m

$1,387

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Sun 1/18

5:55 pm-7:35 pm

2 stops61h 40m

Ko Samui

Sat 1/24

11:40 am-8:44 pm

2 stops45h 04m

$1,444

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Sun 1/18

5:45 pm-1:05 pm

3 stops31h 20m

Ko Samui

Sat 1/24

5:40 pm-10:35 pm

3 stops40h 55m

$1,955

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/4

Showing 1-10 of 19 results
1
2

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 November.
ProviderPrice AccuracyTrust Score*
FlightHubPrice Accuracy3 starsTrust Score*1 star
OvagoPrice Accuracy2 starsTrust Score*2 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
AranGrantPrice Accuracy2 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 eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Washington, D.C.-Ko Samui flight deals on Cheapflights vs. eDreams >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 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 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 November 6, 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?

    Cathay Pacific and British Airways can get you from Washington, D.C. to Ko Samui in just under 36h 30m. Your travel time can differ by up to 25h 10m. There are 9057 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, Washington, D.C. Reagan-National - Ko Samui and Baltimore/Washington - 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

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.