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Ko Samui

$1,117+ Cheap flights from Washington, D.C. (WAS) to Ko Samui (USM)

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 4/20. Fares are subject to change and may not be available on all flights or dates of travel.
WAS — USM
Mar 15 — Mar 221
Sun 3/15
Sun 3/22
1 adult, Economy
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Cheap 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 February 13, 2026.

This Booking.com deal was found by Cheapflights users on 2/13. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/203:10 pm
IAD
-
USM
2 stops31h 10m
Multiple Airlines
Thu 4/303:50 pm
USM
-
IAD
2 stops28h 55m
Multiple Airlines
Deal found 2/13$1,117
This FlightHub deal was found by Cheapflights users on 2/12. 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 4/153:10 pm
IAD
-
USM
2 stops29h 00m
Multiple Airlines
Fri 4/246:00 am
USM
-
IAD
2 stops38h 45m
Multiple Airlines
Deal found 2/12$1,123
This KAYAK deal was found by Cheapflights users on 2/10. 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.
Thu 3/123:35 pm
IAD
-
USM
2 stops29h 10m
Etihad Airways
Thu 3/199:10 pm
USM
-
IAD
2 stops47h 55m
Etihad Airways
Deal found 2/10$1,170
This Etihad Airways deal was found by Cheapflights users on 2/12. 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 Etihad Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/283:35 pm
IAD
-
USM
2 stops28h 35m
Etihad Airways
Sun 11/19:10 pm
USM
-
IAD
2 stops47h 55m
Etihad Airways
Deal found 2/12$1,211
This Trip.com deal was found by Cheapflights users on 2/12. 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 8/19:45 pm
IAD
-
USM
2 stops34h 25m
Multiple Airlines
Sat 8/85:50 pm
USM
-
IAD
2 stops28h 45m
Multiple Airlines
Deal found 2/12$1,307
This BusinessClass deal was found by Cheapflights users on 2/10. 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 BusinessClass is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/131:20 pm
IAD
-
USM
2 stops32h 15m
Multiple Airlines
Fri 4/177:45 pm
USM
-
IAD
2 stops26h 50m
Multiple Airlines
Deal found 2/10$1,334
This Turkish Airlines deal was found by Cheapflights users on 2/9. 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 Turkish Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/179:45 pm
IAD
-
USM
2 stops28h 00m
Turkish Airlines
Wed 5/277:00 pm
USM
-
IAD
2 stops27h 35m
Turkish Airlines
Deal found 2/9$1,345
This FlightHub deal was found by Cheapflights users on 2/10. 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.
Mon 11/308:05 pm
IAD
-
USM
2 stops26h 30m
Multiple Airlines
Mon 12/73:50 pm
USM
-
IAD
2 stops36h 05m
Multiple Airlines
Deal found 2/10$1,376
This Trip.com deal was found by Cheapflights users on 2/12. 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 3/143:35 pm
IAD
-
USM
2 stops29h 10m
Multiple Airlines
Sat 3/218:50 am
USM
-
IAD
2 stops60h 15m
Multiple Airlines
Deal found 2/12$1,382
This Emirates deal was found by Cheapflights users on 2/9. 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 Emirates is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/2811:15 am
IAD
-
USM
2 stops43h 15m
Emirates
Sun 11/18:15 am
USM
-
IAD
2 stops35h 55m
Emirates
Deal found 2/9$1,409
This Cathay Pacific deal was found by Cheapflights users on 2/13. 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 4/206:59 pm
DCA
-
USM
2 stops37h 41m
Multiple Airlines
Thu 4/3011:55 am
USM
-
DCA
2 stops38h 57m
Multiple Airlines
Deal found 2/13$1,419
This oojo deal was found by Cheapflights users on 2/11. 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 4/158:59 am
DCA
-
USM
2 stops47h 41m
Cathay Pacific
Fri 4/2411:55 am
USM
-
DCA
2 stops56h 20m
Cathay Pacific
Deal found 2/11$1,422

Find 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 February 13, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$1,117
(Booking.com)
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

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 February 13, 2026.
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 4/20

3:10 pm-9:20 am

2 stops31h 10m

Ko Samui

Thu 4/30

3:50 pm-9:45 am

2 stops28h 55m

$1,117

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Wed 4/15

3:10 pm-7:10 am

2 stops29h 00m

Ko Samui

Fri 4/24

6:00 am-9:45 am

2 stops38h 45m

$1,123

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Sun 5/17

9:45 pm-12:45 pm

2 stops28h 00m

Ko Samui

Fri 5/29

7:15 pm-11:35 am

2 stops27h 20m

$1,415

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Fri 7/10

1:50 am-8:30 pm

2 stops31h 40m

Ko Samui

Thu 7/16

7:10 pm-10:30 pm

2 stops38h 20m

$1,418

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Mon 4/20

6:59 pm-7:40 pm

2 stops37h 41m

Ko Samui

Thu 4/30

11:55 am-3:52 pm

2 stops38h 57m

$1,419

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Wed 4/15

8:59 am-7:40 pm

2 stops47h 41m

Ko Samui

Fri 4/24

11:55 am-9:15 am

2 stops56h 20m

$1,422

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Mon 4/13

11:36 am-7:40 pm

2 stops45h 04m

Ko Samui

Fri 4/17

11:55 am-12:30 am

2 stops47h 35m

$1,451

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Sat 4/4

11:57 am-7:40 pm

2 stops44h 43m

Ko Samui

Sat 4/11

11:55 am-12:30 am

2 stops47h 35m

$1,452

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Wed 4/15

3:46 pm-7:40 pm

2 stops40h 54m

Ko Samui

Fri 4/24

11:55 am-3:52 pm

2 stops38h 57m

$1,455

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Sat 4/4

1:44 pm-7:40 pm

2 stops42h 56m

Ko Samui

Sat 4/11

11:55 am-12:30 am

2 stops47h 35m

$1,474

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/13

Showing 1-10 of 27 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 February.
ProviderPrice AccuracyTrust Score*
OvagoPrice Accuracy2 starsTrust Score*3 stars
FlightHubPrice 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 February 13, 2026.

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.

How often are flights from Washington, D.C. to Ko Samui delayed?

About 19% of weekly flights between Washington, D.C. and Ko Samui have experienced delays in the past year, with the average delay time being 130 minutes.

What is the most punctual flight time for Washington, D.C. to Ko Samui flights?

Historically, flights departing in the morning are less likely to be delayed, whereas flights leaving at night tend to experience delays more often.

What day of the week experiences the fewest flight delays on this route?

Saturday tends to have the lowest number of delays on this route, whereas Sunday has historically faced a higher average of delays compared to other days of the week.

Which airline has the best punctuality record on Washington, D.C. to Ko Samui flights?

Over the last year, Delta have had the lowest number of delays on this route, with just 11% of flights being delayed.

Reviews of airlines servicing Ko Samui

Get insights into the airlines that provide service to Ko Samui. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Ko Samui. Reviews last updated February 13, 2026.
Peruse reviews from past customers who have flown with Qatar Airways from Washington, D.C. to Ko Samui to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Qatar Airways
7.4
Good
3,731 reviews

Entertainment

7.4

Comfort

7.4

Food

7.3

Boarding

7.5

Crew

7.9

Overall

7.4

Reviews

1 / 20
6.0
Good

Chris,Jul 2025

DFW - DOH

Too crammed for the amount you have to pay. That was very uncomfortable
Qatar Airways
7.4
Good
3,731 reviews
Qatar Airways
7.4
Good
3,731 reviews

Entertainment

7.4

Comfort

7.4

Food

7.3

Boarding

7.5

Crew

7.9

Overall

7.4

Reviews

1 / 20
6.0
Good

Chris,Jul 2025

DFW - DOH

Too crammed for the amount you have to pay. That was very uncomfortable

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, EVA Air, and Cathay Pacific can get you from Washington, D.C. to Ko Samui in just under 28h. Your travel time can differ by up to 19h 41m. 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. Reagan-National - Ko Samui, Washington, D.C. Dulles Intl - 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

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