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Ko Samui

$592+ 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 10/6. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — USM
Oct 11 — Oct 181
Sat 10/11
Sat 10/18
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 September 11, 2025.

Round-trip from

$1,167
(Gotogate)

One-way from

$592
(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 September 11, 2025.

This Gotogate deal was found by Cheapflights users on 9/11. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/262:30 pmIAD - USM
2 stops35h 35mMultiple Airlines
Sun 11/27:00 pmUSM - IAD
3 stops37h 26mMultiple Airlines
Deal found 9/11$1,167
This FlightHub deal was found by Cheapflights users on 9/10. 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.
Wed 10/19:00 pmIAD - USM
2 stops26h 10mMultiple Airlines
Fri 10/314:30 pmUSM - IAD
2 stops35h 25mMultiple Airlines
Deal found 9/10$1,174
This FlightHub deal was found by Cheapflights users on 9/10. 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.
Sat 11/291:30 pmIAD - USM
2 stops30h 40mTurkish Airlines
Sun 1/251:25 pmUSM - IAD
2 stops34h 20mTurkish Airlines
Deal found 9/10$1,176
This Trip.com deal was found by Cheapflights users on 9/10. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/1410:05 pmIAD - USM
2 stops26h 00mMultiple Airlines
Tue 9/163:20 pmUSM - IAD
2 stops35h 50mMultiple Airlines
Deal found 9/10$1,210
This Turkish Airlines deal was found by Cheapflights users on 9/10. 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 Turkish Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/251:30 pmIAD - USM
2 stops31h 45mTurkish Airlines
Mon 9/294:25 pmUSM - IAD
2 stops54h 20mTurkish Airlines
Deal found 9/10$1,251
This oojo deal was found by Cheapflights users on 9/10. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/119:00 pmIAD - USM
2 stops26h 30mMultiple Airlines
Thu 9/185:35 pmUSM - IAD
2 stops26h 05mMultiple Airlines
Deal found 9/10$1,377
This Emirates deal was found by Cheapflights users on 9/11. 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 Emirates is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/2611:15 amIAD - USM
2 stops43h 15mEmirates
Sun 11/28:15 amUSM - IAD
2 stops35h 55mEmirates
Deal found 9/11$1,487
This KAYAK deal was found by Cheapflights users on 9/10. 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.
Sat 11/291:30 pmIAD - USM
2 stops30h 40mTurkish Airlines
Fri 1/307:10 pmUSM - IAD
2 stops36h 05mTurkish Airlines
Deal found 9/10$1,505

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 September 11, 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

Sun 10/26

2:30 pm-1:05 pm

2 stops35h 35m

Ko Samui

Sun 11/2

7:00 pm-8:26 pm

3 stops37h 26m

$1,167

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Wed 10/1

9:00 pm-10:10 am

2 stops26h 10m

Ko Samui

Fri 10/31

4:30 pm-4:55 pm

2 stops35h 25m

$1,174

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Sat 11/29

1:30 pm-8:10 am

2 stops30h 40m

Ko Samui

Mon 1/26

1:25 pm-11:45 am

2 stops34h 20m

$1,176

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Sat 11/29

1:30 pm-8:10 am

2 stops30h 40m

Ko Samui

Sun 1/25

1:25 pm-11:45 am

2 stops34h 20m

$1,176

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Thu 9/25

1:30 pm-8:15 am

2 stops31h 45m

Ko Samui

Mon 9/29

4:25 pm-11:45 am

2 stops54h 20m

$1,251

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Sun 10/26

11:15 am-5:30 pm

2 stops43h 15m

Ko Samui

Sun 11/2

8:15 am-9:10 am

2 stops35h 55m

$1,487

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Mon 10/6

9:40 pm-6:00 pm

2 stops33h 20m

$614

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Sun 10/5

1:30 pm-1:10 pm

2 stops36h 40m

$620

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Sun 10/5

10:05 pm-2:40 pm

3 stops29h 35m

$632

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Tue 10/7

10:05 pm-9:35 pm

3 stops36h 30m

$653

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/10

Showing 1-10 of 18 results
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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 September 11, 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.

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 30h 40m. 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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