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Ko Samui

$559+ 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 9/24. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — USM
ago. 3 — ago. 101
dom. 8/3
dom. 8/10
1 adult, Economy
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Cheap 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 julio 29, 2025.

Round-trip from

$1,146
(Trip.com)

One-way from

$559
(Kiwi.com)
From Washington, D.C. Dulles Intl to Ko Samui
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One-way flight from Washington, D.C. Dulles Intl to Ko Samui
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Find 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 julio 29, 2025.

This FlightHub deal was found by Cheapflights users on 7/28. 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.
sáb. 11/291:30 pmIAD - USM
2 stops40h 10mTurkish Airlines
dom. 1/257:00 amUSM - IAD
2 stops48h 15mTurkish Airlines
Deal found 7/28$1,072
This Trip.com deal was found by Cheapflights users on 7/28. 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.
vie. 9/1210:05 pmIAD - USM
2 stops35h 25mMultiple Airlines
vie. 9/198:00 amUSM - IAD
2 stops43h 10mMultiple Airlines
Deal found 7/28$1,146
This FlightHub deal was found by Cheapflights users on 7/27. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 11/298:05 pmIAD - USM
2 stops27h 50mQatar Airways
lun. 1/266:15 pmUSM - IAD
2 stops33h 40mQatar Airways
Deal found 7/27$1,363

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 julio 29, 2025.
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

vie. 9/12

10:05 pm-8:30 pm

2 stops35h 25m

Ko Samui

vie. 9/19

8:00 am-4:10 pm

2 stops43h 10m

$1,146

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

jue. 9/25

1:30 pm-8:15 am

2 stops31h 45m

Ko Samui

lun. 9/29

3:50 pm-11:45 am

2 stops30h 55m

$1,196

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

mié. 9/24

10:05 pm-7:20 am

3 stops46h 15m

$559

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

mié. 9/24

9:40 pm-8:15 am

2 stops23h 35m

$668

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/27

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 julio 29, 2025.

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 11% 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.

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 julio 29, 2025.
Read through reviews of airlines operating flights from Washington, D.C. Dulles Intl Airport to Ko Samui, such as Turkish Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Turkish Airlines
7.3
Good
3,925 reviews

Crew

7.7

Boarding

7.3

Entertainment

7.4

Comfort

7.3

Food

7.4

Overall

7.3

Reviews

1 / 20
2.0
Mediocre

Brian,Jul 2025

SEA - IST

Horrible check-in experience in Seattle. Was actually yelled at by a customer service rep and then he intentionally would put us in the back row to make sure our seats would not recline. When I complained to customer service they told me they did not find any issues with how we were treated. The sinks did not drain in the bathroom during the flight and my in-flight entertainment never worked during a 12 hour flight. They said they would reset 3 times but never did. Would never fly them again.
Turkish Airlines
7.3
Good
3,925 reviews
Turkish Airlines
7.3
Good
3,925 reviews

Crew

7.7

Boarding

7.3

Entertainment

7.4

Comfort

7.3

Food

7.4

Overall

7.3

Reviews

1 / 20
2.0
Mediocre

Brian,Jul 2025

SEA - IST

Horrible check-in experience in Seattle. Was actually yelled at by a customer service rep and then he intentionally would put us in the back row to make sure our seats would not recline. When I complained to customer service they told me they did not find any issues with how we were treated. The sinks did not drain in the bathroom during the flight and my in-flight entertainment never worked during a 12 hour flight. They said they would reset 3 times but never did. Would never fly them again.

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.

  • What is the cheapest airline to fly from Washington, D.C. Dulles Intl Airport to Ko Samui round-trip?

    Turkish Airlines, at $1,196, was found to be the cheapest airline from Washington, D.C. Dulles Intl Airport to Ko Samui..

  • 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 Pha Ngan
Ko Tao

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