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

In the last 5 days, the lowest price for a flight from Washington, D.C. to Ko Samui was $1,227 for a round-trip ticket.

Which airports will I be using when flying from Washington, D.C. to Ko Samui?

On your way to Ko Samui, you’ll fly out from one of these Washington, D.C. airports: Washington, D.C. Reagan-National or Washington, D.C. Dulles Intl. You’ll be landing at Ko Samui.

Which aircraft models fly most regularly from Washington, D.C. to Ko Samui?

We unfortunately don’t have that data for this specific route.

How does KAYAK find such low prices on flights from Washington, D.C. to Ko Samui?

KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Washington, D.C. to Ko Samui.

How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Washington, D.C. to Ko Samui?

KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Ko Samui from Washington, D.C. is likely to change within 7 days, so travelers know whether to wait or book now.

What is the Hacker Fare option on flights from Washington, D.C. to Ko Samui?

Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Ko Samui with an airline and back to Washington, D.C. with another airline.

What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Washington, D.C. to Ko Samui?

Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Ko Samui from Washington, D.C. up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

How often are flights from Washington, D.C. to Ko Samui delayed?

Weekly flights between Washington, D.C. and Ko Samui historically see delays in approximately 23% of cases , with the average delay over the past year being 125 minutes.

Which airline has the best punctuality record on Washington, D.C. to Ko Samui flights?

Based on our data, United Airlines have experienced the fewest delays on this route in the past 12 months, with only about 12% of their flights encountering any delays.

What day of the week experiences the fewest flight delays on this route?

Statistically, Saturday is the day of the week with the fewest delays on this flight route, while Sunday has typically experienced more delays than other days.

What is the most punctual flight time for Washington, D.C. to Ko Samui flights?

Typically, flights leaving in the morning tend to face fewer delays, whereas flights in the early afternoon have historically encountered delays more often.

$1,227 CHEAP FLIGHTS from Washington, D.C. to Ko Samui (WAS - USM)

Save 21% or more on flights. Compare deals from all over the web.

Never overpay with our price tracking tools.

Filter searches by price, airline and more to find your best flights.

Cheapest round-trip

$1,227

Etihad Airways

Sun 10/11Sat 10/31

IAD - USM • 2 stops

Top airlines

Etihad Airways

Cheapest • from $1,326 (round-trip)

Qatar Airways

Best reviews • 7.3 score

Airline reviews

Nonstop flights

Not available

There are currently no direct flights between Washington, D.C. and Ko Samui. You'll need at least 2 connections.

Insights

Avoid delays

United Airlines

Most punctual • 88% on-time

Morning flights

Best time • Fewest delays

Insights

Start a new search

KAYAK searches 100s of sites at once to find you the best travel deals.

We hope you love your trip to Ko Samui!

Flight Deals

Cheap Flights from Washington, D.C. to Ko Samui (WAS-USM)

Discover the best prices for you by selecting your travel dates on KAYAK.

Round-trip

One-way

Recent round-trip flight deals from Washington, D.C. to Ko Samui

Sun, Oct 11 - Sat, Oct 31

3:10 pm - 7:10 am

IAD

USM

29h 00m

2 stops

4:30 pm - 10:05 am

USM

IAD

28h 35m

2 stops

$1,227Multiple Airlines

Thu, Sep 10 - Mon, Sep 14

3:10 pm - 1:55 pm

IAD

USM

35h 45m

2 stops

12:10 pm - 9:45 am

USM

IAD

32h 35m

2 stops

$1,326Etihad Airways

Thu, Sep 10 - Mon, Sep 14

3:10 pm - 1:55 pm

IAD

USM

35h 45m

2 stops

12:10 pm - 9:45 am

USM

IAD

32h 35m

2 stops

$1,327Etihad Airways

Wed, Aug 19 - Wed, Aug 26

9:00 pm - 11:55 am

IAD

USM

27h 55m

2 stops

7:00 pm - 3:40 pm

USM

IAD

55h 40m

2 stops

$1,579Multiple Airlines

Wed, Aug 19 - Wed, Aug 26

3:10 pm - 8:25 pm

IAD

USM

42h 15m

2 stops

11:05 am - 11:15 am

USM

IAD

35h 10m

3 stops

$1,587Multiple Airlines

Wed, Aug 19 - Wed, Aug 26

3:10 pm - 8:25 pm

IAD

USM

42h 15m

2 stops

8:35 pm - 3:40 pm

USM

IAD

30h 05m

2 stops

$1,595Multiple Airlines

Wed, Aug 19 - Wed, Aug 26

6:59 pm - 7:40 pm

DCA

USM

61h 41m

2 stops

11:55 am - 11:58 pm

USM

DCA

47h 03m

2 stops

$1,857Cathay Pacific

Thu, Sep 17 - Mon, Sep 21

9:30 pm - 9:10 pm

BWI

USM

36h 40m

2 stops

1:30 pm - 5:15 pm

USM

BWI

38h 45m

2 stops

$2,504British Airways

Thu, Sep 17 - Mon, Sep 21

9:30 pm - 9:10 pm

BWI

USM

36h 40m

2 stops

1:30 pm - 5:15 pm

USM

BWI

38h 45m

2 stops

$2,505British Airways

Wed, Jul 22 - Mon, Jul 27

6:55 pm - 7:40 pm

DCA

USM

37h 45m

2 stops

11:55 am - 10:59 am

USM

DCA

34h 04m

2 stops

$2,934Cathay Pacific

Booking Insights

KAYAK's insights & trends for Washington, D.C. to Ko Samui flights

Get data-powered insights and trends into flights from Washington, D.C. to Ko Samui to help you find the cheapest flights, the best time to fly and much more.

Airlines

Delays

Which airlines provide the cheapest flights from Washington, D.C. to Ko Samui?

In the past 5 days, the cheapest round-trip tickets from Washington, D.C. to Ko Samui were found on Etihad Airways ($1,326) and Qatar Airways ($1,811).

Find deals

Cheapest flight	$1,227

Flight from Washington Dulles Airport to Ko Samui

When to book flights from Washington, D.C. to Ko Samui

Are your dates flexible? Find out the best times to travel from Washington, D.C. to Ko Samui based on our flight data from the last year. Discover the cheapest month and even day to fly.

Estimated round-trip price

KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

What is the cheapest flight from Washington, D.C. to Ko Samui?
In the last 5 days, the lowest price for a flight from Washington, D.C. to Ko Samui was $1,227 for a round-trip ticket.
Do I need a passport to fly between Washington, D.C. and Ko Samui?
Yes
Which airports will I be using when flying from Washington, D.C. to Ko Samui?
On your way to Ko Samui, you’ll fly out from one of these Washington, D.C. airports: Washington, D.C. Reagan-National or Washington, D.C. Dulles Intl. You’ll be landing at Ko Samui.
Which aircraft models fly most regularly from Washington, D.C. to Ko Samui?
We unfortunately don’t have that data for this specific route.
How does KAYAK find such low prices on flights from Washington, D.C. to Ko Samui?
KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Washington, D.C. to Ko Samui.
How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Washington, D.C. to Ko Samui?
KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Ko Samui from Washington, D.C. is likely to change within 7 days, so travelers know whether to wait or book now.
What is the Hacker Fare option on flights from Washington, D.C. to Ko Samui?
Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Ko Samui with an airline and back to Washington, D.C. with another airline.
What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Washington, D.C. to Ko Samui?
Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Ko Samui from Washington, D.C. up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top airline flying from Washington, D.C. to Ko Samui

Need help choosing which airline to fly with from Washington, D.C. to Ko Samui? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.

7.3

Qatar AirwaysOverall score based on 3742 reviews

7.5Boarding

7.3Comfort

7.9Crew

7.3Entertainment

7.3Food

Airline reviews

Really good food and service. Qatar Airways is again and again provided an exceptional experience.

10.0 ExcellentAnonymous, May 2026

JFK - BCN

Everything you need to know for your flight from Washington, D.C. to Ko Samui

Airports

Cabin class

Complete your trip

Direct Flights

Flights to other cities

Origins

Other airports

Information on your arrival and departure airports

Ko Samui (USM)

WAS - USM

$1,227 Find Cheap Flights from Washington, D.C. to Ko Samui - Compare and Save

Everything you should know

Cheap Flights from Washington, D.C. to Ko Samui (WAS-USM)

Recent round-trip flight deals from Washington, D.C. to Ko Samui

Recent one-way flight deals from Washington, D.C. to Ko Samui

KAYAK's insights & trends for Washington, D.C. to Ko Samui flights

Which airlines provide the cheapest flights from Washington, D.C. to Ko Samui?

How often are flights from Washington, D.C. to Ko Samui delayed?

What is the most punctual flight time for Washington, D.C. to Ko Samui flights?

What day of the week experiences the fewest flight delays on this route?

Which airline has the best punctuality record on Washington, D.C. to Ko Samui flights?

Good to know

When to book flights from Washington, D.C. to Ko Samui

FAQs for booking flights from Washington, D.C. to Ko Samui

Reviews of the top airline flying from Washington, D.C. to Ko Samui

Everything you need to know for your flight from Washington, D.C. to Ko Samui

Information on your arrival and departure airports

Cabin class types available on flights from Washington, D.C. to Ko Samui

Complete your trip to Ko Samui with a hotel stay or car rental

Find direct flights to and from Washington, D.C. and Ko Samui

Flights to other popular destinations

Flights from domestic origins to Ko Samui

Choose which airport to fly into in Ko Samui