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 16% of their flights experiencing any sort of delay.

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.

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 20% 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 131 minutes.

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 37m on average. On the other hand, flying from Baltimore to Ko Samui takes 33h 45m 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.

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.

$808 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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3:10 pm - 8:25 am

IAD

USM

30h 15m

2 stops

10:00 am - 10:05 am

USM

IAD

35h 05m

2 stops

$1,219Multiple Airlines

dim., oct. 18 - sam., oct. 31

9:45 pm - 3:10 pm

IAD

USM

30h 25m

2 stops

3:50 pm - 11:35 am

USM

IAD

30h 45m

2 stops

$1,322Turkish Airlines

dim., sept. 13 - jeu., sept. 17

9:00 pm - 11:55 am

IAD

USM

27h 55m

2 stops

11:25 am - 8:45 am

USM

IAD

32h 20m

2 stops

$1,410Qatar Airways

dim., sept. 13 - jeu., sept. 17

3:10 pm - 7:30 am

IAD

USM

29h 20m

2 stops

5:55 pm - 9:45 am

USM

IAD

26h 50m

2 stops

$1,615Etihad Airways

dim., juil. 12 - sam., juil. 18

3:10 pm - 8:25 am

IAD

USM

30h 15m

2 stops

1:30 pm - 9:45 am

USM

IAD

31h 15m

2 stops

$1,628Etihad Airways

ven., août 21 - dim., août 30

9:00 pm - 9:10 pm

IAD

USM

37h 10m

2 stops

1:30 pm - 6:20 pm

USM

IAD

39h 50m

2 stops

$1,671Qatar Airways

sam., mai 30 - ven., juin 5

6:59 pm - 7:40 pm

DCA

USM

37h 41m

2 stops

11:55 am - 8:00 pm

USM

DCA

43h 05m

2 stops

$2,177Cathay Pacific

dim., juil. 12 - sam., juil. 18

6:55 pm - 7:40 pm

DCA

USM

37h 45m

2 stops

11:55 am - 9:00 pm

USM

DCA

44h 05m

2 stops

$2,340Cathay Pacific

sam., mai 30 - ven., juin 5

9:35 pm - 9:05 pm

BWI

USM

36h 30m

2 stops

1:25 pm - 6:45 pm

USM

BWI

41h 20m

2 stops

$2,354British Airways

sam., oct. 31 - mar., nov. 3

9:35 pm - 9:10 pm

BWI

USM

36h 35m

2 stops

4:25 pm - 7:45 pm

USM

BWI

38h 20m

2 stops

$2,409British Airways

dim., oct. 18 - sam., oct. 31

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

30h 25m

2 stops

USM3:10 pmKo Samui

Sep 17

USM3:50 pmKo Samui

30h 45m

2 stops

IAD11:35 amWashington, D.C. Dulles Intl

$1,322

Turkish Airlines

Sep 13

IAD9:45 pmWashington, D.C. Dulles Intl

32h 05m

2 stops

USM4:50 pmKo Samui

Sep 17

USM6:25 pmKo Samui

28h 10m

2 stops

IAD11:35 amWashington, D.C. Dulles Intl

$1,379

Turkish Airlines

Jun 7

IAD9:45 pmWashington, D.C. Dulles Intl

29h 00m

2 stops

USM1:45 pmKo Samui

Jun 9

USM5:35 pmKo Samui

29h 00m

2 stops

IAD11:35 amWashington, D.C. Dulles Intl

$1,688

Qatar Airways flights from Washington, D.C. to Ko Samui

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

Qatar Airways

Sep 13

IAD9:00 pmWashington, D.C. Dulles Intl

27h 55m

2 stops

USM11:55 amKo Samui

Sep 17

USM11:25 amKo Samui

32h 20m

2 stops

IAD8:45 amWashington, D.C. Dulles Intl

$1,410

Qatar Airways

May 30

IAD9:00 pmWashington, D.C. Dulles Intl

37h 10m

2 stops

USM9:10 pmKo Samui

Jun 5

USM1:30 pmKo Samui

39h 50m

2 stops

IAD6:20 pmWashington, D.C. Dulles Intl

$1,671

Qatar Airways

May 19

IAD9:00 pmWashington, D.C. Dulles Intl

37h 10m

2 stops

USM9:10 pmKo Samui

May 23

USM1:30 pmKo Samui

39h 50m

2 stops

IAD6:20 pmWashington, D.C. Dulles Intl

$1,686

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

dim. 10/18

3:10 pm-8:25 am

2 stops30h 15m

Ko Samui

sam. 10/31

10:00 am-10:05 am

2 stops35h 05m

$1,219

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

dim. 9/13

9:45 pm-3:10 pm

2 stops30h 25m

Ko Samui

jeu. 9/17

3:50 pm-11:35 am

2 stops30h 45m

$1,322

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

dim. 9/13

9:00 pm-11:55 am

2 stops27h 55m

Ko Samui

jeu. 9/17

11:25 am-8:45 am

2 stops32h 20m

$1,410

Quickest round-trip

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

dim. 7/12

3:10 pm-7:30 am

2 stops29h 20m

Ko Samui

sam. 7/18

5:55 pm-9:45 am

2 stops26h 50m

$1,615

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

ven. 8/21

3:10 pm-8:25 am

2 stops30h 15m

Ko Samui

dim. 8/30

1:30 pm-9:45 am

2 stops31h 15m

$1,628

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

sam. 5/30

9:00 pm-9:10 pm

2 stops37h 10m

Ko Samui

ven. 6/5

1:30 pm-6:20 pm

2 stops39h 50m

$1,671

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

dim. 7/12

6:59 pm-7:40 pm

2 stops37h 41m

Ko Samui

sam. 7/18

11:55 am-8:00 pm

2 stops43h 05m

$2,177

Washington, D.C.Ko Samui

DCA - USM

DCAUSM

Washington, D.C. Reagan-National

sam. 5/30

6:55 pm-7:40 pm

2 stops37h 45m

Ko Samui

ven. 6/5

11:55 am-9:00 pm

2 stops44h 05m

$2,340

BaltimoreKo Samui

BWI - USM

BWIUSM

Baltimore/Washington

sam. 10/31

9:35 pm-9:05 pm

2 stops36h 30m

Ko Samui

mar. 11/3

1:25 pm-6:45 pm

2 stops41h 20m

$2,354

BaltimoreKo Samui

BWI - USM

BWIUSM

Baltimore/Washington

dim. 10/18

9:35 pm-9:10 pm

2 stops36h 35m

Ko Samui

sam. 10/31

4:25 pm-7:45 pm

2 stops38h 20m

$2,409

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 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 airline that flies from Washington, D.C. to Ko Samui?

Qatar Airways and Cathay Pacific are the most popular carriers operating from Washington, D.C. to Ko Samui

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	26h 10m
Direct flights	None

The fastest flight from Washington, D.C. to Ko Samui takes 26h 10m

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.

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Frequently asked questions about flying from Washington, D.C. to Ko Samui

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 26h 10m.
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 $808

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 8/7. 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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Turkish Airlines flights from Washington, D.C. to Ko Samui

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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?

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

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