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$1,282+ Cheap flights from Washington, D.C. (WAS) to Ko Samui (USM)

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 5/15. Fares are subject to change and may not be available on all flights or dates of travel.
WAS — USM
Apr 5 — Apr 121
Sat 4/5
Sat 4/12
1 adult, Economy
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Cheap flight deals from Washington, D.C. to Ko Samui

Discover tips and strategies to find the most affordable flight options for your journey from Washington, D.C. (WAS) 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 March 31, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$1,282
(Trip.com)
Provider with most accurate pricing for Washington, D.C. (WAS)-Ko Samui flight deals.
Search Deals
Provider most trusted by Cheapflights users for Washington, D.C. (WAS)-Ko Samui flights.
Search Deals
From Washington, D.C. (WAS) to Ko Samui
Search Deals

Find flight deals from Washington, D.C. to Ko Samui

Cheapest flights from Washington, D.C. to Ko Samui
Explore the most affordable flight options available from Washington, D.C. to Ko Samui. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 31, 2025.

This Trip.com deal was found by Cheapflights users on 3/30. 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.
Thu 5/151:30 pmIAD - USM
2 stops45h 05mMultiple Airlines
Thu 5/227:00 amUSM - IAD
2 stops39h 45mMultiple Airlines
Deal found 3/30$1,282
This Justfly.com deal was found by Cheapflights users on 3/30. 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 Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/19:40 pmIAD - USM
2 stops24h 40mTurkish Airlines
Fri 10/107:00 amUSM - IAD
2 stops39h 45mTurkish Airlines
Deal found 3/30$1,338
This Mytrip deal was found by Cheapflights users on 3/30. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/158:10 amBWI - USM
3 stops47h 20mMultiple Airlines
Thu 5/227:00 amUSM - BWI
3 stops47h 39mMultiple Airlines
Deal found 3/30$1,374
This StudentUniverse deal was found by Cheapflights users on 3/30. 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 StudentUniverse is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/15:50 pmBWI - USM
2 stops37h 25mSingapore Airlines
Fri 10/101:30 pmUSM - BWI
2 stops38h 17mSingapore Airlines
Deal found 3/30$1,698
This Gurufare deal was found by Cheapflights users on 3/30. 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.
Thu 5/1511:55 amDCA - USM
2 stops43h 40mCathay Pacific
Thu 5/2210:55 amUSM - DCA
2 stops33h 34mCathay Pacific
Deal found 3/30$1,799
This Emirates deal was found by Cheapflights users on 3/30. 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.
Wed 5/1410:55 amIAD - USM
2 stops35h 25mEmirates
Wed 5/218:00 amUSM - IAD
2 stops35h 40mEmirates
Deal found 3/30$1,941
This AranGrant deal was found by Cheapflights users on 3/31. 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 AranGrant is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/145:58 pmIAD - USM
2 stops37h 37mCathay Pacific
Mon 6/3010:55 amUSM - IAD
2 stops54h 55mCathay Pacific
Deal found 3/31$2,427
This KAYAK deal was found by Cheapflights users on 3/30. 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.
Wed 10/19:00 amDCA - USM
3 stops46h 15mSingapore Airlines
Fri 10/101:30 pmUSM - DCA
2 stops42h 25mSingapore Airlines
Deal found 3/30$2,532
This British Airways deal was found by Cheapflights users on 3/30. 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.
Thu 5/159:20 pmBWI - USM
2 stops36h 50mBritish Airways
Thu 5/224:25 pmUSM - BWI
2 stops38h 10mBritish Airways
Deal found 3/30$2,535
This AranGrant deal was found by Cheapflights users on 3/30. 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 AranGrant is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/1410:59 amBWI - USM
2 stops44h 36mCathay Pacific
Mon 6/3010:55 amUSM - BWI
2 stops47h 58mCathay Pacific
Deal found 3/30$2,571
This business-class.com deal was found by Cheapflights users on 3/31. 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.
Mon 4/146:35 amDCA - USM
2 stops25h 00mMultiple Airlines
Mon 6/308:00 amUSM - DCA
3 stops34h 50mMultiple Airlines
Deal found 3/31$2,682
This AranGrant deal was found by Cheapflights users on 3/31. 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 AranGrant is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/167:00 amIAD - USM
2 stops48h 15mSingapore Airlines
Tue 7/11:30 pmUSM - IAD
2 stops28h 20mSingapore Airlines
Deal found 3/31$2,921

Cheapflights Fare Finder

Customize your flight search to find flights from Washington, D.C. 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 March 31, 2025.
Use the filters below to find and compare flights from Washington, D.C. to Ko Samui that are best for you.

Fly from

Washington, D.C.

Fly to

Ko Samui

Route

Depart

Return

Price

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Thu 5/15

1:30 pm-9:35 pm

2 stops45h 05m

Ko Samui

Thu 5/22

7:00 am-11:45 am

2 stops39h 45m

$1,282

BaltimoreKo Samui

BWI - USM

BWIUSM

Baltimore/Washington

Thu 5/15

8:10 am-6:30 pm

3 stops47h 20m

Ko Samui

Thu 5/22

7:00 am-7:39 pm

3 stops47h 39m

$1,374

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Tue 6/17

1:30 pm-8:15 am

2 stops31h 45m

Ko Samui

Fri 7/4

3:25 pm-11:45 am

2 stops31h 20m

$1,478

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Thu 5/15

11:55 am-6:35 pm

2 stops43h 40m

Ko Samui

Thu 5/22

10:55 am-9:29 am

2 stops33h 34m

$1,799

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Wed 5/14

10:55 am-9:20 am

2 stops35h 25m

Ko Samui

Wed 5/21

8:00 am-8:40 am

2 stops35h 40m

$1,941

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Thu 6/19

7:33 pm-6:35 pm

2 stops36h 02m

Ko Samui

Tue 7/1

8:00 am-7:50 am

3 stops34h 50m

$2,146

BaltimoreKo Samui

BWI - USM

BWIUSM

Baltimore/Washington

Tue 6/17

7:12 pm-6:35 pm

2 stops36h 23m

Ko Samui

Fri 7/4

10:55 am-10:17 pm

2 stops46h 22m

$2,319

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Mon 4/14

5:58 pm-6:35 pm

2 stops37h 37m

Ko Samui

Mon 6/30

10:55 am-6:50 am

2 stops54h 55m

$2,427

BaltimoreKo Samui

BWI - USM

BWIUSM

Baltimore/Washington

Thu 5/15

9:20 pm-9:10 pm

2 stops36h 50m

Ko Samui

Thu 5/22

4:25 pm-7:35 pm

2 stops38h 10m

$2,535

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Wed 4/16

7:00 am-6:15 pm

2 stops48h 15m

Ko Samui

Tue 7/1

1:30 pm-6:50 am

2 stops28h 20m

$2,921

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/30

Showing 1-10 of 15 results
1
2

Compare providers for flights from Washington, D.C. 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 Washington, D.C. to Ko Samui in March.
ProviderPrice AccuracyTrust Score*
FlightHubPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice 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.-Ko 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.-Ko Samui flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Washington, D.C.-Ko Samui flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Washington, D.C.-Ko 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.-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 Washington, D.C. to Ko Samui

Have a flexible travel schedule? Discover the best time to fly to Ko Samui from Washington, D.C. 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. to Ko Samui

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

Find hourly flight availability from Washington, D.C. 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 March 31, 2025.

One of the essential ways to save on airfare from Washington, D.C. to Ko Samui is to remain as flexible as possible. Flights that are at noon tend to be the most expensive. A flight in the evening could potentially save you up to 29% on airfare.

What is the cheapest day to fly from Washington, D.C. to Ko Samui?

Use this chart to determine the cheapest time to fly round-trip from Washington, D.C. to Ko Samui. Price data was last updated on March 23, 2025.

Travelers seeking maximum savings on their Washington, D.C. to Ko Samui flight should consider departing on Tuesday mornings when fares are most often at their lowest. Sunday at noon 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 March 31, 2025.
To help decide which airline to fly from Washington, D.C. to Ko Samui, see what other customers have to say about Singapore Airlines, Emirates and Cathay Pacific. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Singapore Airlines
8.1
Very good
1,286 reviews

Boarding

8.2

Overall

8.1

Crew

8.6

Entertainment

8.0

Food

7.7

Comfort

7.9

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
1,286 reviews
Singapore Airlines
8.1
Very good
1,286 reviews

Boarding

8.2

Overall

8.1

Crew

8.6

Entertainment

8.0

Food

7.7

Comfort

7.9

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
3,192 reviews
Singapore Airlines
8.1
Very good
1,286 reviews

Boarding

8.2

Overall

8.1

Crew

8.6

Entertainment

8.0

Food

7.7

Comfort

7.9

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.
Cathay Pacific
7.5
Good
841 reviews
Singapore Airlines
8.1
Very good
1,286 reviews

Boarding

8.2

Overall

8.1

Crew

8.6

Entertainment

8.0

Food

7.7

Comfort

7.9

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.
SWISS
7.5
Good
1,570 reviews
Singapore Airlines
8.1
Very good
1,286 reviews

Boarding

8.2

Overall

8.1

Crew

8.6

Entertainment

8.0

Food

7.7

Comfort

7.9

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
3,748 reviews
Singapore Airlines
8.1
Very good
1,286 reviews

Boarding

8.2

Overall

8.1

Crew

8.6

Entertainment

8.0

Food

7.7

Comfort

7.9

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 Washington, D.C. 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.?

    For a flight from Washington, D.C. to Ko Samui, you will be flying into Ko Samui. Ko Samui (USM) is just 2.1 mi from the center of the city. Ko Samui is the only Ko Samui airport and it handles 0 inbound flights from Washington, D.C. per day. 0 airlines have flights to Ko Samui from Washington, D.C. on a regular basis.

  • What are the cheapest airlines flying from Washington, D.C. to Ko Samui round-trip?

    Currently priced at $1,478, Turkish Airlines will fly you from Washington, D.C. to Ko Samui and back. In addition to Turkish Airlines, many other airlines offer competitively priced options for your trip. Search Cheapflights for deals from Cathay Pacific and Emirates - these airlines can fly you to your destination from $1,799 and $1,941, respectively.

  • What are the most popular routes from Washington, D.C. to Ko Samui?

    The most popular flight routes from Washington, D.C. to Ko Samui are Washington, D.C. Dulles Intl - Ko Samui, Baltimore/Washington - Ko Samui and Washington, D.C. Reagan-National - Ko Samui.

  • Can I find deals for flights from Washington, D.C. to Ko Samui that include hotel bookings?

    Yes. In addition to deals on Washington, D.C. to Ko Samui flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Washington, D.C. to Ko Samui?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Washington, D.C. to Ko Samui.

  • Can I find deals for business class flights from Washington, D.C. to Ko Samui?

    Yes. Cheapflights offers flight deals from Washington, D.C. 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

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