HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Ko Samui

$610+ 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 9/30. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — USM
Aug 5 — Aug 121
Tue 8/5
Tue 8/12
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Dulles Intl 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.

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 July 31, 2025.

Round-trip from

$1,174
(Trip.com)

One-way from

$610
(Kiwi.com)
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

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 July 31, 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.
Sat 11/291:30 pmIAD - USM
2 stops40h 10mTurkish Airlines
Sun 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 7/29. 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.
Fri 9/1210:05 pmIAD - USM
2 stops36h 30mMultiple Airlines
Fri 9/198:45 amUSM - IAD
2 stops42h 25mMultiple Airlines
Deal found 7/29$1,154
This FlightHub deal was found by Cheapflights users on 7/29. 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 11/298:05 pmIAD - USM
2 stops31h 05mQatar Airways
Mon 1/266:15 pmUSM - IAD
2 stops33h 40mQatar Airways
Deal found 7/29$1,367

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 July 31, 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

Sat 11/29

1:30 pm-5:40 pm

2 stops40h 10m

Ko Samui

Sun 1/25

7:00 am-7:15 pm

2 stops48h 15m

$1,072

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Fri 9/12

10:05 pm-9:35 pm

2 stops36h 30m

Ko Samui

Fri 9/19

8:45 am-4:10 pm

2 stops42h 25m

$1,154

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Sat 11/29

8:05 pm-3:10 pm

2 stops31h 05m

Ko Samui

Mon 1/26

6:15 pm-3:55 pm

2 stops33h 40m

$1,367

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Tue 9/30

10:05 pm-7:20 am

3 stops46h 15m

$610

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Sun 11/30

1:30 pm-10:35 am

2 stops33h 05m

$939

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/29

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 July 31, 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 July 31, 2025.
Read through reviews of airlines operating flights from Washington, D.C. Dulles Intl Airport to Ko Samui, such as Qatar Airways and Turkish Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Qatar Airways
7.4
Good
3,609 reviews

Comfort

7.4

Boarding

7.5

Crew

7.9

Entertainment

7.4

Overall

7.4

Food

7.3

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
3,609 reviews
Qatar Airways
7.4
Good
3,609 reviews

Comfort

7.4

Boarding

7.5

Crew

7.9

Entertainment

7.4

Overall

7.4

Food

7.3

Reviews

1 / 20
6.0
Good

Chris,Jul 2025

DFW - DOH

Too crammed for the amount you have to pay. That was very uncomfortable
Turkish Airlines
7.3
Good
3,933 reviews
Qatar Airways
7.4
Good
3,609 reviews

Comfort

7.4

Boarding

7.5

Crew

7.9

Entertainment

7.4

Overall

7.4

Food

7.3

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 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 are the cheapest airlines flying from Washington, D.C. Dulles Intl Airport to Ko Samui round-trip?

    Turkish Airlines, at $1,175, was found to be the cheapest airline from Washington, D.C. Dulles Intl Airport to Ko Samui. An alternate airline flying to your destination would be Qatar Airways.

  • 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

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.