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Ko Samui

$942+ 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 6/8. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — USM
Apr 22 — Apr 291
Tue 4/22
Tue 4/29
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 April 17, 2025.

Most accurate provider

AranGrant
3 stars

Most trusted provider

AranGrant
3 stars

Round-trip from

$1,441
(FlightHub)

One-way from

$942
(Kiwi.com)
Provider with most accurate pricing for Washington, D.C. Dulles Intl-Ko Samui flight deals.
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Provider most trusted by Cheapflights users for Washington, D.C. Dulles Intl-Ko Samui flights.
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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 April 17, 2025.

This FlightHub deal was found by Cheapflights users on 4/17. 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 10/19:40 pmIAD - USM
2 stops23h 35mTurkish Airlines
Fri 10/316:05 pmUSM - IAD
2 stops29h 10mTurkish Airlines
Deal found 4/17$1,252
This FlightHub deal was found by Cheapflights users on 4/16. 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.
Sun 11/308:05 pmIAD - USM
2 stops26h 35mQatar Airways
Tue 2/106:15 pmUSM - IAD
2 stops33h 40mQatar Airways
Deal found 4/16$1,323
This Emirates deal was found by Cheapflights users on 4/16. 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.
Thu 11/2710:30 amIAD - USM
2 stops43h 00mEmirates
Tue 2/105:40 pmUSM - IAD
2 stops26h 30mEmirates
Deal found 4/16$1,532
This oojo deal was found by Cheapflights users on 4/17. 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 10/110:55 amIAD - USM
2 stops41h 15mMultiple Airlines
Fri 10/318:30 pmUSM - IAD
3 stops34h 35mMultiple Airlines
Deal found 4/17$1,569
This British Airways deal was found by Cheapflights users on 4/16. 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 British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/19:55 pmIAD - USM
2 stops32h 20mBritish Airways
Thu 2/124:25 pmUSM - IAD
2 stops35h 10mBritish Airways
Deal found 4/16$2,069
This oojo deal was found by Cheapflights users on 4/17. 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.
Fri 7/45:34 pmIAD - USM
2 stops37h 41mSingapore Airlines
Fri 7/114:25 pmUSM - IAD
3 stops59h 00mSingapore Airlines
Deal found 4/17$4,031

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 April 17, 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

Mon 5/26

1:30 pm-8:15 am

2 stops31h 45m

Ko Samui

Tue 6/10

3:50 pm-11:45 am

2 stops30h 55m

$1,441

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Sun 6/8

1:30 pm-1:10 pm

2 stops36h 40m

Ko Samui

Sun 6/15

7:30 pm-11:45 am

2 stops27h 15m

$1,580

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Sat 5/31

10:55 am-11:40 am

2 stops61h 45m

Ko Samui

Sat 6/7

8:00 am-8:40 am

2 stops35h 40m

$2,478

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Fri 7/4

5:34 pm-6:15 pm

2 stops37h 41m

Ko Samui

Fri 7/11

4:25 pm-4:25 pm

3 stops59h 00m

$4,031

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Sun 6/8

10:05 pm-7:50 am

3 stops46h 45m

$942

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/16

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 April.
ProviderPrice AccuracyTrust Score*
FlightHubPrice Accuracy3 starsTrust Score*2 stars
AranGrantPrice 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. Dulles Intl Airport-Ko Samui flights, users find the pricing of AranGrant to be most consistent on Cheapflights vs. AranGrant Users can find the same prices on Washington, D.C. Dulles Intl Airport-Ko Samui flight deals on Cheapflights vs. AranGrant >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 AranGrant the most. AranGrant 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 April 17, 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.

Rainfall in Ko Samui by month

Plan your trip to Ko Samui by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Ko Samui ranges from 2.3 - 19.3 inches per month. November is typically the wettest month, when rainfall can reach 19.3 in. February is typically the driest time to visit Ko Samui when rainfall is around 2.3 in.

Temperature in Ko Samui by month

Plan your trip to Ko Samui by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Ko Samui, use this chart to help with planning. For those seeking warmer temperatures, April is the ideal time of year to visit, when temperatures reach an average of 84.2 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 80.6 F).

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 April 17, 2025.
Singapore Airlines
8.1
Very good
1,288 reviews

Entertainment

8.0

Boarding

8.2

Comfort

7.9

Overall

8.1

Crew

8.6

Food

7.7

Reviews

1 / 20
8.0
Excellent

Anonymous,Dec 2024

NRT - LAX

Crew and in flight experience were great! I felt safe in the plane. Only downside was sitting in economy and the seat/person in front of me who had their seat reclined most of the flight (9 hrs) which made it difficult to eat or be fully comfortable.
Singapore Airlines
8.1
Very good
1,288 reviews
Singapore Airlines
8.1
Very good
1,288 reviews

Entertainment

8.0

Boarding

8.2

Comfort

7.9

Overall

8.1

Crew

8.6

Food

7.7

Reviews

1 / 20
8.0
Excellent

Anonymous,Dec 2024

NRT - LAX

Crew and in flight experience were great! I felt safe in the plane. Only downside was sitting in economy and the seat/person in front of me who had their seat reclined most of the flight (9 hrs) which made it difficult to eat or be fully comfortable.
Emirates
8.0
Very good
3,200 reviews
Singapore Airlines
8.1
Very good
1,288 reviews

Entertainment

8.0

Boarding

8.2

Comfort

7.9

Overall

8.1

Crew

8.6

Food

7.7

Reviews

1 / 20
8.0
Excellent

Anonymous,Dec 2024

NRT - LAX

Crew and in flight experience were great! I felt safe in the plane. Only downside was sitting in economy and the seat/person in front of me who had their seat reclined most of the flight (9 hrs) which made it difficult to eat or be fully comfortable.
Turkish Airlines
7.3
Good
3,769 reviews
Singapore Airlines
8.1
Very good
1,288 reviews

Entertainment

8.0

Boarding

8.2

Comfort

7.9

Overall

8.1

Crew

8.6

Food

7.7

Reviews

1 / 20
8.0
Excellent

Anonymous,Dec 2024

NRT - LAX

Crew and in flight experience were great! I felt safe in the plane. Only downside was sitting in economy and the seat/person in front of me who had their seat reclined most of the flight (9 hrs) which made it difficult to eat or be fully comfortable.

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 $1,441, was found to be the cheapest airline from Washington, D.C. Dulles Intl Airport to Ko Samui.Alternate airlines to your destination round-trip include Emirates and Singapore Airlines.

  • 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 Washington, D.C. Dulles Intl Airport?

Book flights to Washington, D.C. Dulles Intl Airport if you plan to visit one of these locations
Ko Tao
Ko Pha Ngan

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