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

Saturday is statistically the day of the week which experiences the fewest number of delays on this flight route. Sunday has historically seen more delays on average compared to the rest of the week.

How long does it take to fly to Ko Samui?

Flight times vary depending on what airport in Washington, D.C. you fly out of and what airport in Ko Samui you fly into. For example, flying from Washington, D.C. to Ko Samui takes 26h 50m on average. On the other hand, flying from Baltimore to Ko Samui takes 27h 40m on average. Keep in mind that it’s always quicker to opt for a non-stop flight, so be sure to check momondo if there are any available for your route.

What is the cheapest airline that flies from Washington, D.C. to Ko Samui?

Cathay Pacific is the most popular carrier operating from Washington, D.C. to Ko Samui

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

Generally, flights departing in the morning tend to experience fewer delays. Flights in the evening have, in the past, seen delays more frequently in comparison.

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

Historically, on average around 19% of flights between Washington, D.C. and Ko Samui have experienced a delay on any given week. The average delay length over the past 12 months has been 133 minutes.

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

According to our data, Delta have had the least number of delays on this route over the last 12 months; with about 15% of their flights experiencing any sort of delay.

When did momondo last update prices for flights from Washington, D.C. to Ko Samui Airport?

Prices for flights from Washington, D.C. to Ko Samui Airport are updated daily.

How old do you have to be to fly from Washington, D.C. to Ko Samui Airport?

The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Washington, D.C. to Ko Samui Airport.

What documentation or ID do you need to fly to Ko Samui Airport?

The required travel and health documents for your Ko Samui Airport trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at Ko Samui Airport. We recommend that you seek guidance from your airline or a reliable third party such as IATA.

$143 Cheap Flights from Washington, D.C. to Ko Samui in 2026

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Find the cheapest flights from Washington, D.C. to Ko Samui

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Cheap round-trip flights

Enter your travel dates to find the best prices.

3:10 pm - 7:10 am

IAD

USM

29h 00m

2 stops

7:00 pm - 9:45 am

USM

IAD

49h 45m

2 stops

$1,044Multiple Airlines

Sat, Apr 18 - Sat, Apr 25

3:10 pm - 8:15 am

IAD

USM

30h 05m

2 stops

5:25 pm - 9:45 am

USM

IAD

27h 20m

2 stops

$1,061Multiple Airlines

Sat, May 2 - Sat, May 9

2:05 pm - 7:30 am

IAD

USM

54h 25m

2 stops

8:45 am - 9:45 am

USM

IAD

36h 00m

2 stops

$1,156Etihad Airways

Thu, Apr 2 - Fri, Apr 24

3:10 pm - 7:30 am

IAD

USM

29h 20m

2 stops

3:25 pm - 9:45 am

USM

IAD

29h 20m

2 stops

$1,205Multiple Airlines

Mon, Apr 6 - Mon, Apr 20

9:45 pm - 11:40 am

IAD

USM

26h 55m

2 stops

7:10 pm - 11:35 am

USM

IAD

27h 25m

2 stops

$1,234Turkish Airlines

Sun, Sep 13 - Thu, Sep 17

3:10 pm - 7:30 am

IAD

USM

29h 20m

2 stops

10:05 am - 9:45 am

USM

IAD

34h 40m

2 stops

$1,247Multiple Airlines

Tue, Apr 7 - Sun, Apr 19

9:45 pm - 11:40 am

IAD

USM

26h 55m

2 stops

3:25 pm - 11:35 am

USM

IAD

31h 10m

2 stops

$1,250Turkish Airlines

Sat, May 2 - Thu, May 7

6:59 pm - 7:40 pm

DCA

USM

37h 41m

2 stops

11:55 am - 5:59 pm

USM

DCA

41h 04m

2 stops

$1,566Cathay Pacific

Tue, May 5 - Tue, May 12

6:59 pm - 7:40 pm

DCA

USM

61h 41m

2 stops

11:55 am - 5:59 pm

USM

DCA

41h 04m

2 stops

$1,581Cathay Pacific

Sat, May 9 - Sat, May 16

9:30 pm - 9:10 pm

BWI

USM

36h 40m

2 stops

1:30 pm - 7:45 pm

USM

BWI

41h 15m

2 stops

$2,782British Airways

Sat, May 2 - Sat, May 9

Emirates flights from Washington, D.C. to Ko Samui

Our best Emirates deals on Washington, D.C. to Ko Samui flight tickets

Emirates

May 4

IAD10:55 amWashington, D.C. Dulles Intl

44h 05m

2 stops

USM6:00 pmKo Samui

May 8

USM8:00 amKo Samui

35h 40m

2 stops

IAD8:40 amWashington, D.C. Dulles Intl

$1,340

Emirates

May 5

IAD10:55 amWashington, D.C. Dulles Intl

44h 05m

2 stops

USM6:00 pmKo Samui

May 12

USM5:55 pmKo Samui

49h 45m

2 stops

IAD8:40 amWashington, D.C. Dulles Intl

$1,359

Emirates

May 5

IAD10:55 amWashington, D.C. Dulles Intl

43h 00m

2 stops

USM4:55 pmKo Samui

May 7

USM7:00 pmKo Samui

48h 40m

2 stops

IAD8:40 amWashington, D.C. Dulles Intl

$1,403

Turkish Airlines flights from Washington, D.C. to Ko Samui

Our best Turkish Airlines deals on Washington, D.C. to Ko Samui flight tickets

Turkish Airlines

Sep 13

IAD9:45 pmWashington, D.C. Dulles Intl

26h 55m

2 stops

USM11:40 amKo Samui

Sep 17

USM7:10 pmKo Samui

27h 25m

2 stops

IAD11:35 amWashington, D.C. Dulles Intl

$1,234

Turkish Airlines

May 2

IAD9:45 pmWashington, D.C. Dulles Intl

26h 55m

2 stops

USM11:40 amKo Samui

May 7

USM3:25 pmKo Samui

31h 10m

2 stops

IAD11:35 amWashington, D.C. Dulles Intl

$1,250

Turkish Airlines

May 4

IAD9:45 pmWashington, D.C. Dulles Intl

23h 30m

2 stops

USM8:15 amKo Samui

May 7

USM7:45 pmKo Samui

26h 50m

2 stops

IAD11:35 amWashington, D.C. Dulles Intl

$1,268

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Sat 4/18

3:10 pm-7:10 am

2 stops29h 00m

Ko Samui

Sat 4/25

7:00 pm-9:45 am

2 stops49h 45m

$1,044

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Sat 5/2

3:10 pm-8:15 am

2 stops30h 05m

Ko Samui

Sat 5/9

5:25 pm-9:45 am

2 stops27h 20m

$1,061

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Thu 4/2

2:05 pm-7:30 am

2 stops54h 25m

Ko Samui

Fri 4/24

8:45 am-9:45 am

2 stops36h 00m

$1,156

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Mon 4/6

3:10 pm-7:30 am

2 stops29h 20m

Ko Samui

Mon 4/20

3:25 pm-9:45 am

2 stops29h 20m

$1,205

Quickest round-trip

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Sun 9/13

9:45 pm-11:40 am

2 stops26h 55m

Ko Samui

Thu 9/17

7:10 pm-11:35 am

2 stops27h 25m

$1,234

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Tue 4/7

3:10 pm-7:30 am

2 stops29h 20m

Ko Samui

Sun 4/19

10:05 am-9:45 am

2 stops34h 40m

$1,247

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

Sat 5/2

9:45 pm-11:40 am

2 stops26h 55m

Ko Samui

Thu 5/7

3:25 pm-11:35 am

2 stops31h 10m

$1,250

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Tue 5/5

6:59 pm-7:40 pm

2 stops37h 41m

Ko Samui

Tue 5/12

11:55 am-5:59 pm

2 stops41h 04m

$1,566

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

Sat 5/9

6:59 pm-7:40 pm

2 stops61h 41m

Ko Samui

Sat 5/16

11:55 am-5:59 pm

2 stops41h 04m

$1,581

BaltimoreKo Samui

BWI - USM

BWIUSM

Baltimore/Washington

Sat 5/2

9:30 pm-9:10 pm

2 stops36h 40m

Ko Samui

Sat 5/9

1:30 pm-7:45 pm

2 stops41h 15m

$2,782

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 16 resultsSorted by cheapest first

How to get the cheapest flight ticket from Washington, D.C. to Ko Samui

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

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Other information

What is the cheapest day to depart on your flight to Ko Samui?

Our data shows that Wednesday is the least expensive day to fly to Ko Samui. Tickets to fly out on this day can be as low as $325. Flights from Washington, D.C. to Ko Samui on a Sunday will generally be more expensive and average around $714. Keep in mind that these prices on both days could fluctuate depending on the season and the demand.

What is the cheapest time of day to depart on your flight to Ko Samui?

Our data shows that the cheapest Washington, D.C. to Ko Samui flights are usually those with departure times in the evening. Our users have found flights to Ko Samui in the evening for as low as $286. At noon is when there is more demand to fly to Ko Samui, so prices are often more expensive at around $399 per ticket.

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

Are you open to changing your travel dates? Check out the ideal times to fly from Washington, D.C. to Ko Samui according to our flight data. Find out which month and days have the cheapest flights.

Estimated round-trip price

Cheap Washington, D.C. to Ko Samui (WAS to USM) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Washington, D.C. to Ko Samui

Fastest flight time	24h 35m
Direct flights	None

The fastest flight from Washington, D.C. to Ko Samui takes 24h 35m

There are no direct flights from Washington, D.C. to Ko Samui. There are no popular flight routes from Washington, D.C. to Ko Samui.

Search flight deals

How far is Washington, D.C. to Ko Samui by plane?
Washington, D.C. and Ko Samui are 9079.2 mi apart from one another. A reasonable flight in good conditions will take 24h 35m.
When did momondo last update prices for flights from Washington, D.C. to Ko Samui Airport?
Prices for flights from Washington, D.C. to Ko Samui Airport are updated daily.
How old do you have to be to fly from Washington, D.C. to Ko Samui Airport?
The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Washington, D.C. to Ko Samui Airport.
What documentation or ID do you need to fly to Ko Samui Airport?
The required travel and health documents for your Ko Samui Airport trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at Ko Samui Airport. We recommend that you seek guidance from your airline or a reliable third party such as IATA.
What is the most popular airline from Washington, D.C. to Ko Samui?
Based on momondo bookings for flights between Washington, D.C. and Ko Samui, the leading airline is Qatar Airways, making up 100% of the total bookings.

Ko Pha Ngan

Ko Tao

Khanom

Why use momondo?

Why should I use momondo to find a flight deal from Washington, D.C. to Ko Samui?

It is quick and easy to find Washington, D.C. to Ko Samui flights on momondo. We search and return numerous flight options from various airlines and agents. You can then use our filters to narrow your search until you have found the most convenient flight to Ko Samui that suits you.

Can I find flights from Washington, D.C. to Ko Samui with flexible booking policies on momondo?

All flight searches from Washington, D.C. to Ko Samui on momondo can be filtered to show those which offer flexible booking policies.

How can momondo help me find flights from Washington, D.C. to Ko Samui?

Once all potential Washington, D.C. to Ko Samui flight options are in front of you, momondo lets you sort and filter flights based on preferences such as airline, price and flight times amongst many other options.

I’m not ready to book a flight from Washington, D.C. to Ko Samui right now. Can momondo alert me if prices change?

Yes. momondo can track prices for Washington, D.C. to Ko Samui flights and alert you when they change. Perform a search to set up the price alert. All that is required is a valid email address.

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Cheap flights from Washington, D.C. to Ko Samui from $505

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Washington, D.C. to Ko Samui departing on 5/4. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

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How to get the cheapest flight ticket from Washington, D.C. to Ko Samui

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What is the cheapest time of day to depart on your flight to Ko Samui?

What is the cheapest airline that flies 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?

How long does it take to fly to Ko Samui?

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

Cheap Washington, D.C. to Ko Samui (WAS to USM) flight deals and tips

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