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.

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).

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

Saturday flights are generally found to be more expensive for flights from Washington, D.C. Reagan-National Airport to Ko Samui. This shouldn’t discourage you from searching, as you can still find great deals by being flexible with your options. Use our search form to find deals on tickets to Ko Samui.

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.

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.

$654+ Flights from Washington, D.C. Reagan-National Airport to Ko Samui

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Cheap flight deals from Reagan-National to Ko Samui

Round-trip from	$1,719 (Gurufare)
One-way from	$654 (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 julio 29, 2025.

jue. 8/287:31 pmDCA - USM

2 stops36h 04mCathay Pacific

jue. 9/410:55 amUSM - DCA

2 stops32h 04mCathay Pacific

Deal found 7/29

$1,719

jue. 9/188:59 amDCA - USM

2 stops46h 16mSingapore Airlines

lun. 9/224:25 pmUSM - DCA

3 stops63h 34mSingapore Airlines

Deal found 7/27

$2,213

Best flights from Reagan-National to Ko Samui
Discover carefully curated flight deals from Reagan-National to Ko Samui that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated julio 29, 2025.

jue. 8/287:31 pmDCA - USM

2 stops36h 04mCathay Pacific

jue. 9/410:55 amUSM - DCA

2 stops32h 04mCathay Pacific

Deal found 7/29

$1,719

jue. 9/188:59 amDCA - USM

2 stops46h 16mSingapore Airlines

lun. 9/224:25 pmUSM - DCA

3 stops63h 34mSingapore Airlines

Deal found 7/27

$2,213

Last-minute flights from Reagan-National to Ko Samui
Discover last-minute flight deals from Reagan-National to Ko Samui. Data last updated julio 29, 2025 and is based on user searches.

mar. 7/296:00 amDCA - USM

2 stops49h 35mCathay Pacific

mar. 8/510:55 amUSM - DCA

2 stops45h 04mCathay Pacific

Deal found 7/28

$2,529

mar. 7/299:59 amDCA - USM

3 stops45h 16mSingapore Airlines

mar. 8/51:30 pmUSM - DCA

2 stops43h 12mSingapore Airlines

Deal found 7/28

$3,532

One-way flights from Reagan-National to Ko Samui
Search for one-way flight options from Reagan-National to Ko Samui. Find affordable one-way fares based on user searches. Data last updated julio 29, 2025.

mié. 9/248:00 amDCA - USM

3 stops36h 20mMultiple Airlines

Deal found 7/27

$654

mié. 9/248:59 amDCA - USM

2 stops46h 16mSingapore Airlines

Deal found 7/27

$977

mar. 9/236:19 amDCA - USM

2 stops25h 16mCathay Pacific

Deal found 7/27

$1,000

Cheapflights Fare Finder

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

Fly to

Route

Depart

Return

Price

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

jue. 8/28

7:31 pm-6:35 pm

2 stops36h 04m

Ko Samui

jue. 9/4

10:55 am-7:59 am

2 stops32h 04m

$1,719

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

jue. 9/18

8:59 am-6:15 pm

2 stops46h 16m

Ko Samui

lun. 9/22

4:25 pm-8:59 pm

3 stops63h 34m

$2,213

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

mié. 9/24

8:00 am-7:20 am

3 stops36h 20m

$654

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

mié. 9/24

8:59 am-6:15 pm

2 stops46h 16m

$977

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

mar. 9/23

6:19 am-6:35 pm

2 stops25h 16m

$1,000

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/27

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?

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?

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.

Reviews of airlines servicing Ko Samui

Read reviews from past customers who have flown Singapore Airlines and Cathay Pacific from Washington, D.C. Reagan-National Airport to Ko Samui. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.

Singapore Airlines

8.1

Very good

1,335 reviews

Reviews

1 / 20

6.0

Good

Pierre,Apr 2025

MLE - SIN

3 boarding pass checkpoints at the gate. Long line before boarding. Poor leg room in economy.. Flight crew rounds practically non existent during flight.

Singapore Airlines

8.1

Very good

1,335 reviews

Singapore Airlines

8.1

Very good

1,335 reviews

Reviews

1 / 20

6.0

Good

Pierre,Apr 2025

MLE - SIN

3 boarding pass checkpoints at the gate. Long line before boarding. Poor leg room in economy.. Flight crew rounds practically non existent during flight.

Cathay Pacific

7.6

Good

948 reviews

Singapore Airlines

8.1

Very good

1,335 reviews

Reviews

1 / 20

6.0

Good

Pierre,Apr 2025

MLE - SIN

3 boarding pass checkpoints at the gate. Long line before boarding. Poor leg room in economy.. Flight crew rounds practically non existent during flight.

Related info for your journey

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.
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.

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$654+ 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 9/24. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from Reagan-National to Ko Samui with Cheapflights

1. Tell us where you want to go

2. Select your favorite providers

3. Compare prices and book

Cheap flight deals from Reagan-National to Ko Samui

Round-trip from

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Find flight deals from Reagan-National to Ko Samui

Cheapest flights from Reagan-National to Ko SamuiExplore 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 julio 29, 2025.

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 julio 29, 2025.

Cheapflights Fare Finder

Use the filters below to find and compare flights from Washington, D.C. Reagan-National Airport to Ko Samui that are best for you.

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.

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 julio 29, 2025.

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.

Reviews of airlines servicing Ko Samui

Read reviews from past customers who have flown Singapore Airlines and Cathay Pacific from Washington, D.C. Reagan-National Airport to Ko Samui. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.

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?

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

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

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

Traveling to a place near Ko Samui?

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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 julio 29, 2025.