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Ko Samui

$745+ Cheap flights from Reagan-National (DCA) 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 10/7. Fares are subject to change and may not be available on all flights or dates of travel.
DCA — USM
Oct 11 — Oct 181
Sat 10/11
Sat 10/18
1 adult, Economy
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Cheap flight deals from Reagan-National to Ko Samui

Discover tips and strategies to find the most affordable flight options for your journey from Reagan-National (DCA) 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 September 11, 2025.

Round-trip from

$1,431
(Mytrip)

One-way from

$745
(Kiwi.com)
From Washington, D.C. Reagan-National to Ko Samui
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One-way flight from Washington, D.C. Reagan-National to Ko Samui
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Find flight deals from Reagan-National to Ko Samui

Cheapest flights from Reagan-National to Ko Samui
Explore the most affordable flight options available from Reagan-National to Ko Samui. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 11, 2025.

This Mytrip deal was found by Cheapflights users on 9/11. 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.
Sun 10/269:40 amDCA - USM
3 stops35h 30mMultiple Airlines
Sun 11/27:00 pmUSM - DCA
3 stops36h 45mMultiple Airlines
Deal found 9/11$1,431
This oojo deal was found by Cheapflights users on 9/10. 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.
Thu 9/113:33 pmDCA - USM
2 stops40h 02mCathay Pacific
Thu 9/1810:55 amUSM - DCA
2 stops45h 04mCathay Pacific
Deal found 9/10$1,645
This oojo deal was found by Cheapflights users on 9/10. 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.
Sun 9/146:19 amDCA - USM
2 stops25h 16mCathay Pacific
Tue 9/1610:55 amUSM - DCA
2 stops42h 04mCathay Pacific
Deal found 9/10$2,412
This Mytrip deal was found by Cheapflights users on 9/10. 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.
Sun 9/149:40 amDCA - USM
3 stops35h 10mMultiple Airlines
Tue 9/167:25 pmUSM - DCA
3 stops35h 19mMultiple Airlines
Deal found 9/10$2,566
This Gurufare deal was found by Cheapflights users on 9/11. 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.
Sun 10/269:59 amDCA - USM
2 stops45h 16mSingapore Airlines
Sun 11/21:25 pmUSM - DCA
2 stops42h 35mSingapore Airlines
Deal found 9/11$3,254
This Booking.com deal was found by Cheapflights users on 9/10. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/1111:00 amDCA - USM
3 stops33h 35mMultiple Airlines
Thu 9/1810:55 amUSM - DCA
3 stops33h 04mMultiple Airlines
Deal found 9/10$7,211

Cheapflights Fare Finder

 
Customize your flight search to find flights from Reagan-National 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 September 11, 2025.
Use the filters below to find and compare flights from Washington, D.C. Reagan-National Airport to Ko Samui that are best for you.

Fly from

Reagan-National

Fly to

Ko Samui

Route

Depart

Return

Price

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Sun 10/26

9:40 am-8:10 am

3 stops35h 30m

Ko Samui

Sun 11/2

7:00 pm-7:45 pm

3 stops36h 45m

$1,431

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Sun 10/26

9:59 am-6:15 pm

2 stops45h 16m

Ko Samui

Sun 11/2

1:25 pm-8:00 pm

2 stops42h 35m

$3,254

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Tue 10/7

6:59 pm-7:50 am

2 stops49h 51m

$765

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Sun 10/5

9:59 am-7:50 am

3 stops34h 51m

$832

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Mon 10/6

7:02 pm-6:35 pm

2 stops36h 33m

$885

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Sun 10/5

12:25 pm-6:35 pm

2 stops43h 10m

$1,172

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Wed 10/8

6:59 pm-1:55 pm

3 stops55h 56m

$1,542

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Thu 10/9

9:59 am-6:30 pm

3 stops45h 31m

$1,858

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Wed 10/1

8:59 am-4:35 pm

3 stops44h 36m

$3,344

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Fri 10/3

8:59 am-3:10 pm

3 stops43h 11m

$3,384

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/10

Showing 1-10 of 12 results
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Best time to book a flight from Reagan-National to Ko Samui

Have a flexible travel schedule? Discover the best time to fly to Ko Samui from Reagan-National 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. Reagan-National Airport to Ko Samui

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

Find hourly flight availability from Reagan-National 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 September 11, 2025.

One of the essential ways to save on airfare from Washington, D.C. Reagan-National Airport 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 48% on airfare.

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

Use this chart to determine the cheapest time to fly round-trip from Reagan-National to Ko Samui. Price data was last updated on March 30, 2025.

Travelers seeking maximum savings on their Washington, D.C. Reagan-National Airport to Ko Samui flight should consider departing on Wednesday evenings 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.

Related info for your journey

Find useful and relevant information for your journey from Reagan-National 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. Reagan-National?

    Most people fly into Ko Samui (USM) if they book a flight to Ko Samui from Washington, D.C. Reagan-National. On average, Ko Samui has 0 inbound flights from Washington, D.C. Reagan-National per day from 0 airlines. Ko Samui is conveniently located just 2.1 mi from Ko Samui’s city center.

  • How long is the flight from Washington, D.C. Reagan-National Airport to Ko Samui?

    There are many flights that can get you from Washington, D.C. Reagan-National Airport to Ko Samui in 45h 16m. Fly via Singapore Airlines to get the fastest option. Washington, D.C. Reagan-National Airport and Ko Samui are separated by a distance of 9081 mi.

  • Can I find deals for flights from Reagan-National to Ko Samui that include hotel bookings?

    Yes. In addition to deals on Reagan-National to Ko Samui flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Reagan-National to Ko Samui?

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

  • Can I find deals for business class flights from Reagan-National to Ko Samui?

    Yes. Cheapflights offers flight deals from Reagan-National 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

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