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Ko Samui

$551+ Cheap flights from Dulles Intl (IAD) 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 3/9. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — USM
feb. 26 — mar. 51
jue. 2/26
jue. 3/5
1 adult, Economy
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Cheap flight deals from Dulles Intl to Ko Samui

Cheapest flights from Dulles Intl to Ko Samui
Explore the most affordable flight options available from Dulles Intl to Ko Samui. Find the lowest fares from popular airlines and budget airlines, with prices last updated on enero 27, 2026.

This oojo deal was found by Cheapflights users on 1/27. 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.
vie. 3/132:30 pm
IAD
-
USM
2 stops30h 15m
Multiple Airlines
vie. 3/207:35 pm
USM
-
IAD
2 stops28h 10m
Multiple Airlines
Deal found 1/27$1,142
This KAYAK deal was found by Cheapflights users on 1/27. 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.
dom. 5/171:20 pm
IAD
-
USM
2 stops41h 55m
Turkish Airlines
mar. 5/266:25 pm
USM
-
IAD
2 stops36h 25m
Turkish Airlines
Deal found 1/27$1,271
This KAYAK deal was found by Cheapflights users on 1/27. 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.
dom. 5/171:20 pm
IAD
-
USM
2 stops41h 55m
Turkish Airlines
vie. 5/297:50 am
USM
-
IAD
2 stops38h 45m
Turkish Airlines
Deal found 1/27$1,286
This KAYAK deal was found by Cheapflights users on 1/27. 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.
mar. 5/191:20 pm
IAD
-
USM
2 stops36h 50m
Turkish Airlines
jue. 5/286:25 pm
USM
-
IAD
2 stops28h 10m
Turkish Airlines
Deal found 1/27$1,296
This KAYAK deal was found by Cheapflights users on 1/27. 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.
mié. 5/209:45 pm
IAD
-
USM
2 stops31h 50m
Turkish Airlines
mar. 5/267:10 pm
USM
-
IAD
2 stops35h 40m
Turkish Airlines
Deal found 1/27$1,299
This Gurufare deal was found by Cheapflights users on 1/27. 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 Gurufare is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 5/191:20 pm
IAD
-
USM
2 stops36h 50m
Turkish Airlines
sáb. 5/303:50 pm
USM
-
IAD
2 stops30h 45m
Turkish Airlines
Deal found 1/27$1,300
This KAYAK deal was found by Cheapflights users on 1/27. 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.
mié. 5/209:45 pm
IAD
-
USM
2 stops30h 00m
Turkish Airlines
vie. 5/297:50 am
USM
-
IAD
2 stops38h 45m
Turkish Airlines
Deal found 1/27$1,314
This KAYAK deal was found by Cheapflights users on 1/27. 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.
dom. 5/171:20 pm
IAD
-
USM
2 stops36h 50m
Turkish Airlines
jue. 5/288:50 pm
USM
-
IAD
2 stops34h 00m
Turkish Airlines
Deal found 1/27$1,342
This KAYAK deal was found by Cheapflights users on 1/27. 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.
dom. 5/171:20 pm
IAD
-
USM
2 stops36h 50m
Turkish Airlines
lun. 6/18:45 am
USM
-
IAD
2 stops37h 50m
Turkish Airlines
Deal found 1/27$1,353
This KAYAK deal was found by Cheapflights users on 1/27. 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.
mié. 5/209:45 pm
IAD
-
USM
2 stops31h 00m
Turkish Airlines
mié. 5/273:20 pm
USM
-
IAD
2 stops31h 15m
Turkish Airlines
Deal found 1/27$1,369
This KAYAK deal was found by Cheapflights users on 1/27. 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.
mié. 5/209:45 pm
IAD
-
USM
2 stops30h 00m
Turkish Airlines
lun. 6/18:45 am
USM
-
IAD
2 stops37h 50m
Turkish Airlines
Deal found 1/27$1,379

Find flight deals from Dulles Intl to Ko Samui

Discover tips and strategies to find the most affordable flight options for your journey from Dulles Intl (IAD) 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 enero 27, 2026.

Most accurate provider

Ovago
2 stars

Most trusted provider

Ovago
3 stars

Round-trip from

$1,271
(KAYAK)

One-way from

$651
(Kiwi.com)
Provider with most accurate pricing for Washington, D.C. Dulles Intl-Ko Samui flight deals.
Search Deals
Provider most trusted by Cheapflights users for Washington, D.C. Dulles Intl-Ko Samui flights.
Search Deals
From Washington, D.C. Dulles Intl to Ko Samui
Search Deals
One-way flight from Washington, D.C. Dulles Intl to Ko Samui
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Dulles Intl 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 enero 27, 2026.
Use the filters below to find and compare flights from Washington, D.C. Dulles Intl Airport to Ko Samui that are best for you.

Fly from

Dulles Intl

Fly to

Ko Samui

Route

Depart

Return

Price

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

dom. 5/17

1:20 pm-6:15 pm

2 stops41h 55m

Ko Samui

mar. 5/26

6:25 pm-7:50 pm

2 stops36h 25m

$1,271

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

dom. 5/17

1:20 pm-6:15 pm

2 stops41h 55m

Ko Samui

vie. 5/29

7:50 am-11:35 am

2 stops38h 45m

$1,286

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

mié. 5/20

9:45 pm-3:45 pm

2 stops31h 00m

Ko Samui

dom. 5/31

7:50 am-11:35 am

2 stops38h 45m

$1,314

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

mié. 5/20

9:45 pm-2:45 pm

2 stops30h 00m

Ko Samui

vie. 5/29

7:50 am-11:35 am

2 stops38h 45m

$1,314

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

dom. 5/17

1:20 pm-1:10 pm

2 stops36h 50m

Ko Samui

jue. 5/28

8:50 pm-7:50 pm

2 stops34h 00m

$1,342

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

dom. 5/17

1:20 pm-1:10 pm

2 stops36h 50m

Ko Samui

lun. 6/1

8:45 am-11:35 am

2 stops37h 50m

$1,353

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

mié. 5/20

9:45 pm-4:35 pm

2 stops31h 50m

Ko Samui

jue. 5/28

2:00 pm-11:35 am

2 stops32h 35m

$1,369

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

mar. 5/19

1:20 pm-1:10 pm

2 stops36h 50m

Ko Samui

vie. 5/29

4:25 pm-11:35 am

2 stops30h 10m

$1,408

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

mar. 5/19

9:45 pm-11:05 am

2 stops26h 20m

Ko Samui

mar. 5/26

7:10 pm-7:50 pm

2 stops35h 40m

$1,514

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

lun. 5/18

9:45 pm-9:10 pm

2 stops36h 25m

Ko Samui

mar. 5/26

2:35 pm-7:50 pm

2 stops40h 15m

$1,517

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/27

Showing 1-10 of 18 results
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Compare providers for flights from Dulles Intl 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 Dulles Intl to Ko Samui in January.
ProviderPrice AccuracyTrust Score*
OvagoPrice Accuracy2 starsTrust Score*3 stars
AranGrantPrice Accuracy2 starsTrust Score*2 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. Dulles Intl Airport-Ko Samui flights, users find the pricing of Ovago to be most consistent on Cheapflights vs. Ovago Users can find the same prices on Washington, D.C. Dulles Intl Airport-Ko Samui flight deals on Cheapflights vs. Ovago 90-95% of the time. Price accuracy is based on data collected from Washington, D.C. Dulles Intl Airport-Ko Samui flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Washington, D.C. Dulles Intl Airport-Ko Samui flights, Cheapflights users trust Ovago the most. Ovago 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. Dulles Intl Airport-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 Dulles Intl to Ko Samui

Have a flexible travel schedule? Discover the best time to fly to Ko Samui from Dulles Intl 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. Dulles Intl Airport to Ko Samui

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

Find hourly flight availability from Dulles Intl 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 enero 27, 2026.

It’s optimal to fly from Washington, D.C. Dulles Intl Airport to Ko Samui in the morning. By choosing this option you can save up to 10% on the cost of your flight, compared to a flight in the afternoon.

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

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

Travelers seeking maximum savings on their Washington, D.C. Dulles Intl Airport to Ko Samui flight should consider departing on Monday at noon when fares are most often at their lowest. Saturday 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 Dulles Intl 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. Dulles Intl?

    Located just 2.1 mi from the city center, Ko Samui is the airport most travelers will use when flying to Ko Samui from Washington, D.C. Dulles Intl. Booking flights from Washington, D.C. Dulles Intl to Ko Samui (USM) should be relatively easy as there are 0 daily inbound flights from Washington, D.C. Dulles Intl from 0 different airlines.

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

    There are many flights that can get you from Washington, D.C. Dulles Intl Airport to Ko Samui in 41h 55m. Fly via Turkish Airlines to get the fastest option. Airlines will cover a distance of 9076 mi.

  • Can I find deals for flights from Dulles Intl to Ko Samui that include hotel bookings?

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

  • How can I find direct flights from Dulles Intl to Ko Samui?

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

  • Can I find deals for business class flights from Dulles Intl to Ko Samui?

    Yes. Cheapflights offers flight deals from Dulles Intl 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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