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Ko Samui

$642+ Cheap flights from Washington, D.C. (WAS) 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 10/17. Fares are subject to change and may not be available on all flights or dates of travel.
WAS — USM
Jul 5 — Jul 121
Sat 7/5
Sat 7/12
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 June 30, 2025.

Round-trip from

$1,261
(Trip.com)

One-way from

$642
(Kiwi.com)
From Washington, D.C. (WAS) to Ko Samui
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One-way flight 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 June 30, 2025.

This Gurufare deal was found by Cheapflights users on 6/30. 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.
Mon 9/86:00 amBWI - USM
3 stops39h 15mJapan Airlines
Sat 9/137:00 amUSM - BWI
3 stops51h 47mJapan Airlines
Deal found 6/30$1,258
This Trip.com deal was found by Cheapflights users on 6/30. 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.
Sat 11/298:05 pmIAD - USM
2 stops36h 20mMultiple Airlines
Mon 1/267:00 amUSM - IAD
2 stops61h 20mMultiple Airlines
Deal found 6/30$1,261
This SmartFares deal was found by Cheapflights users on 6/30. 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 SmartFares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/89:40 pmIAD - USM
2 stops52h 30mTurkish Airlines
Sat 9/131:30 pmUSM - IAD
2 stops33h 15mTurkish Airlines
Deal found 6/30$1,318
This FlightHub deal was found by Cheapflights users on 6/28. 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 11/298:05 pmIAD - USM
2 stops26h 35mQatar Airways
Mon 1/263:05 pmUSM - IAD
2 stops36h 50mQatar Airways
Deal found 6/28$1,371
This Mytrip deal was found by Cheapflights users on 6/27. 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.
Tue 8/126:22 pmBWI - USM
3 stops35h 18mMultiple Airlines
Tue 8/198:00 amUSM - BWI
3 stops33h 54mMultiple Airlines
Deal found 6/27$1,437
This Emirates deal was found by Cheapflights users on 6/30. 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.
Sat 11/2910:30 amIAD - USM
2 stops41h 05mEmirates
Fri 1/307:55 amUSM - IAD
2 stops36h 15mEmirates
Deal found 6/30$1,481
This Cathay Pacific deal was found by Cheapflights users on 6/29. 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 Cathay Pacific is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/187:33 pmDCA - USM
2 stops36h 02mCathay Pacific
Mon 9/2210:55 amUSM - DCA
2 stops32h 04mCathay Pacific
Deal found 6/29$1,798
This Gurufare deal was found by Cheapflights users on 6/30. 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.
Mon 9/811:23 amBWI - USM
2 stops44h 12mCathay Pacific
Sat 9/133:30 pmUSM - BWI
3 stops67h 17mCathay Pacific
Deal found 6/30$1,960
This Singapore Airlines deal was found by Cheapflights users on 6/29. 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 Singapore Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/188:59 amDCA - USM
2 stops46h 16mSingapore Airlines
Mon 9/224:25 pmUSM - DCA
3 stops63h 34mSingapore Airlines
Deal found 6/29$1,969
This Singapore Airlines deal was found by Cheapflights users on 6/29. 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 Singapore Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/186:55 pmBWI - USM
2 stops63h 15mSingapore Airlines
Mon 9/221:30 pmUSM - BWI
2 stops38h 37mSingapore Airlines
Deal found 6/29$2,019
This Mytrip deal was found by Cheapflights users on 6/29. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/16:00 amDCA - USM
2 stops25h 35mMultiple Airlines
Fri 8/1510:55 amUSM - DCA
3 stops34h 23mMultiple Airlines
Deal found 6/29$2,378
This British Airways deal was found by Cheapflights users on 6/28. 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 British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/19:20 pmBWI - USM
2 stops33h 55mBritish Airways
Fri 10/314:25 pmUSM - BWI
2 stops38h 20mBritish Airways
Deal found 6/28$2,411

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 June 30, 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

BaltimoreKo Samui

BWI - USM

BWIUSM

Baltimore/Washington

Mon 9/8

6:00 am-8:15 am

3 stops39h 15m

Ko Samui

Sat 9/13

7:00 am-11:47 pm

3 stops51h 47m

$1,258

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Mon 9/8

9:40 pm-1:10 pm

2 stops52h 30m

Ko Samui

Sat 9/13

1:30 pm-11:45 am

2 stops33h 15m

$1,318

BaltimoreKo Samui

BWI - USM

BWIUSM

Baltimore/Washington

Tue 8/12

6:22 pm-4:40 pm

3 stops35h 18m

Ko Samui

Tue 8/19

8:00 am-6:54 am

3 stops33h 54m

$1,437

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Thu 9/25

9:00 pm-11:55 am

2 stops27h 55m

Ko Samui

Mon 9/29

2:30 pm-3:40 pm

2 stops36h 10m

$1,455

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Mon 9/8

1:30 pm-8:15 am

2 stops31h 45m

Ko Samui

Sat 9/13

3:25 pm-4:10 pm

3 stops35h 45m

$1,538

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Thu 9/18

7:33 pm-6:35 pm

2 stops36h 02m

Ko Samui

Mon 9/22

10:55 am-7:59 am

2 stops32h 04m

$1,798

BaltimoreKo Samui

BWI - USM

BWIUSM

Baltimore/Washington

Mon 9/8

11:23 am-6:35 pm

2 stops44h 12m

Ko Samui

Sat 9/13

3:30 pm-11:47 pm

3 stops67h 17m

$1,960

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Thu 9/18

8:59 am-6:15 pm

2 stops46h 16m

Ko Samui

Mon 9/22

4:25 pm-8:59 pm

3 stops63h 34m

$1,969

BaltimoreKo Samui

BWI - USM

BWIUSM

Baltimore/Washington

Thu 9/18

6:55 pm-9:10 pm

2 stops63h 15m

Ko Samui

Mon 9/22

1:30 pm-5:07 pm

2 stops38h 37m

$2,019

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Fri 8/1

6:00 am-6:35 pm

2 stops25h 35m

Ko Samui

Fri 8/15

10:55 am-10:18 am

3 stops34h 23m

$2,378

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/28

Showing 1-10 of 18 results
1
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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 June 30, 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 30, 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 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 June 30, 2025.
Peruse reviews from past customers who have flown with Emirates, Singapore Airlines, and Cathay Pacific from Washington, D.C. to Ko Samui to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Emirates
8.1
Very good
3,285 reviews

Comfort

8.0

Boarding

8.1

Food

7.8

Crew

8.3

Entertainment

8.2

Overall

8.1

Reviews

1 / 20
4.0
Okay

Anonymous,Dec 2024

IAD - DXB

Not so good. Flight was departed 2 hours late from DC and we missed our connecting flight from Dubai to Mumbai. Our flight Dubai to Mumbai got delayed by three hours. Once we arrived Bombay airport we didnot get all our luggage bags. We were missing two luggage bags so found out that our those two luggage bags are coming in different flight. First they gave us wrong flight information in which our missing luggage coming and wrong phone number to whom we should reach out. I spent hours and hours at the airport to find out our luggage bags. After four five hours later and hectic time at the airport to get our luggage bags. Overall poor communication with emirates staff at the airport and no one is helpful.
Emirates
8.1
Very good
3,285 reviews
Emirates
8.1
Very good
3,285 reviews

Comfort

8.0

Boarding

8.1

Food

7.8

Crew

8.3

Entertainment

8.2

Overall

8.1

Reviews

1 / 20
4.0
Okay

Anonymous,Dec 2024

IAD - DXB

Not so good. Flight was departed 2 hours late from DC and we missed our connecting flight from Dubai to Mumbai. Our flight Dubai to Mumbai got delayed by three hours. Once we arrived Bombay airport we didnot get all our luggage bags. We were missing two luggage bags so found out that our those two luggage bags are coming in different flight. First they gave us wrong flight information in which our missing luggage coming and wrong phone number to whom we should reach out. I spent hours and hours at the airport to find out our luggage bags. After four five hours later and hectic time at the airport to get our luggage bags. Overall poor communication with emirates staff at the airport and no one is helpful.
Singapore Airlines
8.1
Very good
1,319 reviews
Emirates
8.1
Very good
3,285 reviews

Comfort

8.0

Boarding

8.1

Food

7.8

Crew

8.3

Entertainment

8.2

Overall

8.1

Reviews

1 / 20
4.0
Okay

Anonymous,Dec 2024

IAD - DXB

Not so good. Flight was departed 2 hours late from DC and we missed our connecting flight from Dubai to Mumbai. Our flight Dubai to Mumbai got delayed by three hours. Once we arrived Bombay airport we didnot get all our luggage bags. We were missing two luggage bags so found out that our those two luggage bags are coming in different flight. First they gave us wrong flight information in which our missing luggage coming and wrong phone number to whom we should reach out. I spent hours and hours at the airport to find out our luggage bags. After four five hours later and hectic time at the airport to get our luggage bags. Overall poor communication with emirates staff at the airport and no one is helpful.
Cathay Pacific
7.6
Good
921 reviews
Emirates
8.1
Very good
3,285 reviews

Comfort

8.0

Boarding

8.1

Food

7.8

Crew

8.3

Entertainment

8.2

Overall

8.1

Reviews

1 / 20
4.0
Okay

Anonymous,Dec 2024

IAD - DXB

Not so good. Flight was departed 2 hours late from DC and we missed our connecting flight from Dubai to Mumbai. Our flight Dubai to Mumbai got delayed by three hours. Once we arrived Bombay airport we didnot get all our luggage bags. We were missing two luggage bags so found out that our those two luggage bags are coming in different flight. First they gave us wrong flight information in which our missing luggage coming and wrong phone number to whom we should reach out. I spent hours and hours at the airport to find out our luggage bags. After four five hours later and hectic time at the airport to get our luggage bags. Overall poor communication with emirates staff at the airport and no one is helpful.
SWISS
7.5
Good
1,654 reviews
Emirates
8.1
Very good
3,285 reviews

Comfort

8.0

Boarding

8.1

Food

7.8

Crew

8.3

Entertainment

8.2

Overall

8.1

Reviews

1 / 20
4.0
Okay

Anonymous,Dec 2024

IAD - DXB

Not so good. Flight was departed 2 hours late from DC and we missed our connecting flight from Dubai to Mumbai. Our flight Dubai to Mumbai got delayed by three hours. Once we arrived Bombay airport we didnot get all our luggage bags. We were missing two luggage bags so found out that our those two luggage bags are coming in different flight. First they gave us wrong flight information in which our missing luggage coming and wrong phone number to whom we should reach out. I spent hours and hours at the airport to find out our luggage bags. After four five hours later and hectic time at the airport to get our luggage bags. Overall poor communication with emirates staff at the airport and no one is helpful.
Qatar Airways
7.4
Good
3,596 reviews
Emirates
8.1
Very good
3,285 reviews

Comfort

8.0

Boarding

8.1

Food

7.8

Crew

8.3

Entertainment

8.2

Overall

8.1

Reviews

1 / 20
4.0
Okay

Anonymous,Dec 2024

IAD - DXB

Not so good. Flight was departed 2 hours late from DC and we missed our connecting flight from Dubai to Mumbai. Our flight Dubai to Mumbai got delayed by three hours. Once we arrived Bombay airport we didnot get all our luggage bags. We were missing two luggage bags so found out that our those two luggage bags are coming in different flight. First they gave us wrong flight information in which our missing luggage coming and wrong phone number to whom we should reach out. I spent hours and hours at the airport to find out our luggage bags. After four five hours later and hectic time at the airport to get our luggage bags. Overall poor communication with emirates staff at the airport and no one is helpful.

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 $1,371, Qatar Airways will fly you from Washington, D.C. to Ko Samui and back. In addition to Qatar Airways, many other airlines offer competitively priced options for your trip. Search Cheapflights for deals from Turkish Airlines and Emirates - these airlines can fly you to your destination from $1,389 and $1,481, 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.

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