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Koh Samui

$606+ Cheap flights from Dulles Intl (IAD) to Koh 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 2/24. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — USM
févr. 25 — mars 41
mar. 2/25
mar. 3/4
1 adult, Economy
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Cheap flight deals from Dulles Intl to Koh Samui

Discover tips and strategies to find the most affordable flight options for your journey from Dulles Intl (IAD) to Koh 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 février 20, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$1,307
(SmartFares)

One-way from

$606
(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 Koh Samui

Cheapest flights from Dulles Intl to Koh Samui
Explore the most affordable flight options available from Dulles Intl to Koh Samui. Find the lowest fares from popular airlines and budget airlines, with prices last updated on février 20, 2025.

This FlightHub deal was found by Cheapflights users on 2/19. 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.
lun. 9/19:40 pmIAD - USM
2 stops25h 30mTurkish Airlines
sam. 9/66:55 pmUSM - IAD
2 stops26h 50mTurkish Airlines
Deal found 2/19$1,289
This SmartFares deal was found by Cheapflights users on 2/19. 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 SmartFares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mer. 3/129:05 pmIAD - USM
2 stops34h 10mMultiple Airlines
mar. 3/1811:40 amUSM - IAD
2 stops32h 40mMultiple Airlines
Deal found 2/19$1,307
This KAYAK deal was found by Cheapflights users on 2/20. 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.
ven. 3/219:05 pmIAD - USM
2 stops33h 25mQatar Airways
ven. 4/255:55 pmUSM - IAD
2 stops32h 45mQatar Airways
Deal found 2/20$1,540
This Gurufare deal was found by Cheapflights users on 2/19. 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.
lun. 9/17:55 pmIAD - USM
2 stops59h 20mSingapore Airlines
sam. 9/64:25 pmUSM - IAD
3 stops59h 25mSingapore Airlines
Deal found 2/19$2,199
This business-class.com deal was found by Cheapflights users on 2/19. 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 business-class.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mer. 3/196:35 pmIAD - USM
3 stops39h 10mLufthansa
sam. 3/291:25 pmUSM - IAD
2 stops37h 25mLufthansa
Deal found 2/19$9,029

Find flights from Dulles Intl to Koh Samui within your budget

Customize your flight search to find flights from Dulles Intl to Koh 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 février 20, 2025.

Fly from

Dulles Intl

Fly to

Koh Samui

Route

Depart

Return

Price

Washington, D.C.Koh Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

mer. 3/12

9:05 pm-6:15 pm

2 stops34h 10m

Ko Samui

mar. 3/18

11:40 am-9:20 am

2 stops32h 40m

$1,307

Washington, D.C.Koh Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

mar. 6/17

12:30 pm-6:15 pm

2 stops42h 45m

Ko Samui

ven. 7/4

1:30 pm-10:45 am

2 stops32h 15m

$1,726

Washington, D.C.Koh Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

dim. 6/8

7:25 pm-9:10 pm

3 stops62h 45m

Ko Samui

jeu. 6/19

1:30 pm-4:50 pm

2 stops38h 20m

$3,069

Washington, D.C.Koh Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

ven. 5/23

11:00 am-7:20 am

2 stops33h 20m

Ko Samui

sam. 5/31

9:30 pm-3:40 pm

2 stops29h 10m

$5,833

Washington, D.C.Koh Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

mer. 3/19

6:35 pm-8:45 pm

3 stops39h 10m

Ko Samui

sam. 3/29

1:25 pm-3:50 pm

2 stops37h 25m

$9,029

Washington, D.C.Koh Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

mer. 2/26

9:30 pm-8:20 am

3 stops46h 50m

$609

Washington, D.C.Koh Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

mer. 2/26

8:05 pm-8:50 pm

2 stops36h 45m

$640

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/19

Compare providers for flights from Dulles Intl to Koh 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 Koh Samui in February.
ProviderPrice AccuracyTrust Score*
FlightHubPrice Accuracy3 starsTrust Score*3 stars
AranGrantPrice Accuracy3 starsTrust Score*1 star

*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-Koh Samui flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Washington, D.C. Dulles Intl Airport-Koh Samui flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Washington, D.C. Dulles Intl Airport-Koh 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-Koh Samui flights, Cheapflights users trust FlightHub the most. FlightHub 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-Koh 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 Koh Samui

Have a flexible travel schedule? Discover the best time to fly to Koh 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.

Travel insights for flights from Dulles Intl to Koh Samui

Get recent, data-driven insights about flights from Dulles Intl to Koh Samui including ideal travel times, pricing trends, and more.

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

Find hourly flight availability from Dulles Intl to Koh Samui. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated février 20, 2025.

It’s optimal to fly from Washington, D.C. Dulles Intl Airport to Koh Samui at noon. By choosing this option you can save up to 23% 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 Koh Samui?

Use this chart to determine the cheapest time to fly round-trip from Dulles Intl to Koh Samui. Price data was last updated on February 16, 2025.

Travelers seeking maximum savings on their Washington, D.C. Dulles Intl Airport to Koh 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 Koh Samui by month

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

In terms of precipitation, rainfall in Koh 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 Koh Samui when rainfall is around 2.3 in.

Temperature in Koh Samui by month

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

If weather is an important factor for your trip to Koh 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 Koh Samui

Get insights into the airlines that provide service to Koh 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 Koh Samui. Reviews last updated février 20, 2025.
Qatar Airways
7.4
Good
3,609 reviews

Comfort

7.4

Food

7.3

Entertainment

7.4

Overall

7.4

Crew

8.0

Boarding

7.6

Reviews

1 / 20

4.0
Okay

Khalil,Nov 2024

SEA - DOH

Organized and punctual departure process. The flight was full and the seat pitch is inadequate given the ultra long flight. It looks like the airline has increased the seat rows to maximize the payload, but overlooked the comfort factor. I was in economy at a window seat, but had half a window to my seat! The cabin temperature was a little warm, when I tried to open the overhead vent, the one in front was too far and started blowing air on the passenger in front of me, and the same for the vent behind me, it was for the passenger behinde. It looked as if an extra row was cramped between every two rows. The family behind me had a child who was constantly crying and banging his head against my seat. It's not the airline's fault, but the lack of space aggravated the situation.

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

Comfort

7.4

Food

7.3

Entertainment

7.4

Overall

7.4

Crew

8.0

Boarding

7.6

Reviews

1 / 20

4.0
Okay

Khalil,Nov 2024

SEA - DOH

Organized and punctual departure process. The flight was full and the seat pitch is inadequate given the ultra long flight. It looks like the airline has increased the seat rows to maximize the payload, but overlooked the comfort factor. I was in economy at a window seat, but had half a window to my seat! The cabin temperature was a little warm, when I tried to open the overhead vent, the one in front was too far and started blowing air on the passenger in front of me, and the same for the vent behind me, it was for the passenger behinde. It looked as if an extra row was cramped between every two rows. The family behind me had a child who was constantly crying and banging his head against my seat. It's not the airline's fault, but the lack of space aggravated the situation.

Turkish Airlines
7.3
Good
3,832 reviews
Qatar Airways
7.4
Good
3,609 reviews

Comfort

7.4

Food

7.3

Entertainment

7.4

Overall

7.4

Crew

8.0

Boarding

7.6

Reviews

1 / 20

4.0
Okay

Khalil,Nov 2024

SEA - DOH

Organized and punctual departure process. The flight was full and the seat pitch is inadequate given the ultra long flight. It looks like the airline has increased the seat rows to maximize the payload, but overlooked the comfort factor. I was in economy at a window seat, but had half a window to my seat! The cabin temperature was a little warm, when I tried to open the overhead vent, the one in front was too far and started blowing air on the passenger in front of me, and the same for the vent behind me, it was for the passenger behinde. It looked as if an extra row was cramped between every two rows. The family behind me had a child who was constantly crying and banging his head against my seat. It's not the airline's fault, but the lack of space aggravated the situation.

Lufthansa
6.7
Okay
6,984 reviews
Qatar Airways
7.4
Good
3,609 reviews

Comfort

7.4

Food

7.3

Entertainment

7.4

Overall

7.4

Crew

8.0

Boarding

7.6

Reviews

1 / 20

4.0
Okay

Khalil,Nov 2024

SEA - DOH

Organized and punctual departure process. The flight was full and the seat pitch is inadequate given the ultra long flight. It looks like the airline has increased the seat rows to maximize the payload, but overlooked the comfort factor. I was in economy at a window seat, but had half a window to my seat! The cabin temperature was a little warm, when I tried to open the overhead vent, the one in front was too far and started blowing air on the passenger in front of me, and the same for the vent behind me, it was for the passenger behinde. It looked as if an extra row was cramped between every two rows. The family behind me had a child who was constantly crying and banging his head against my seat. It's not the airline's fault, but the lack of space aggravated the situation.

Related info for your journey

Find useful and relevant information for your journey from Dulles Intl to Koh 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 Koh 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 Koh 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 Koh Samui round-trip?

    Cheapflights users have booked flights from Washington, D.C. Dulles Intl Airport to Koh Samui round-trip from $1,540. Other airlines that can offer you cheap pricing are Turkish Airlines, from $5,374, and Lufthansa, from $9,029.

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

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

  • How can I find direct flights from Dulles Intl to Koh 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 Koh Samui.

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

    Yes. Cheapflights offers flight deals from Dulles Intl to Koh 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 Pha Ngan
Ko Tao

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