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

Thursday is statistically the day of the week which experiences the fewest number of delays on this flight route. Wednesday 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 at night have, in the past, seen delays more frequently in comparison.

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 11% of their flights experiencing any sort of delay.

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

Historically, on average around 14% 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 136 minutes.

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

Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Washington, D.C. Dulles Intl Airport to Ko Samui Airport.

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

The travel and health documents required for your trip to Ko Samui Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Ko Samui Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

$90 Cheap Flights from Washington, D.C. Dulles Intl Airport to Ko Samui in 2026

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

Round-trip

One-way

Cheap round-trip flights

Enter your travel dates to find the best prices.

3:10 pm - 8:25 am

IAD

USM

30h 15m

2 stops

6:00 am - 9:45 am

USM

IAD

38h 45m

2 stops

$1,102Multiple Airlines

mié., may. 6 - jue., may. 14

1:20 pm - 8:15 am

IAD

USM

31h 55m

2 stops

6:00 am - 11:35 am

USM

IAD

40h 35m

2 stops

$1,136Turkish Airlines

sáb., may. 9 - dom., may. 17

3:10 pm - 10:30 am

IAD

USM

32h 20m

2 stops

6:00 am - 9:45 am

USM

IAD

38h 45m

2 stops

$1,143Multiple Airlines

sáb., may. 9 - dom., may. 17

3:10 pm - 7:10 am

IAD

USM

29h 00m

2 stops

5:25 pm - 9:45 am

USM

IAD

27h 20m

2 stops

$1,242Etihad Airways

jue., ago. 13 - mié., ago. 19

3:10 pm - 7:30 am

IAD

USM

29h 20m

2 stops

8:55 am - 9:45 am

USM

IAD

59h 50m

2 stops

$1,261Etihad Airways

mié., abr. 15 - mié., abr. 22

3:10 pm - 11:05 am

IAD

USM

32h 55m

2 stops

9:00 pm - 9:45 am

USM

IAD

47h 45m

2 stops

$1,267Multiple Airlines

vie., abr. 17 - vie., abr. 24

3:10 pm - 7:10 am

IAD

USM

29h 00m

2 stops

7:00 pm - 9:45 am

USM

IAD

49h 45m

2 stops

$1,272Multiple Airlines

vie., abr. 24 - lun., may. 4

3:10 pm - 8:25 am

IAD

USM

30h 15m

2 stops

6:00 am - 9:45 am

USM

IAD

38h 45m

2 stops

$1,278Multiple Airlines

sáb., abr. 18 - sáb., abr. 25

3:35 pm - 7:30 am

IAD

USM

28h 55m

2 stops

8:15 am - 10:05 am

USM

IAD

60h 50m

2 stops

$1,340Multiple Airlines

jue., mar. 19 - lun., mar. 23

1:20 pm - 10:45 am

IAD

USM

34h 25m

2 stops

1:30 pm - 11:35 am

USM

IAD

33h 05m

2 stops

$1,352Multiple Airlines

vie., abr. 10 - mié., abr. 22

Cathay Pacific flights from Washington, D.C. Dulles Intl Airport to Ko Samui

Our best Cathay Pacific deals on Washington, D.C. Dulles Intl Airport to Ko Samui flight tickets

Cathay Pacific

Apr 8

IAD5:59 pmWashington, D.C. Dulles Intl

38h 41m

2 stops

USM7:40 pmKo Samui

Apr 21

USM11:55 amKo Samui

46h 31m

2 stops

IAD11:26 pmWashington, D.C. Dulles Intl

$1,438

Cathay Pacific

Apr 4

IAD5:52 pmWashington, D.C. Dulles Intl

38h 48m

2 stops

USM7:40 pmKo Samui

Apr 11

USM11:55 amKo Samui

46h 31m

2 stops

IAD11:26 pmWashington, D.C. Dulles Intl

$1,785

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

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

Qatar Airways

Apr 7

IAD9:00 pmWashington, D.C. Dulles Intl

34h 00m

2 stops

USM6:00 pmKo Samui

Apr 24

USM6:00 amKo Samui

61h 40m

2 stops

IAD8:40 amWashington, D.C. Dulles Intl

$1,468

Qatar Airways

Apr 7

IAD9:00 pmWashington, D.C. Dulles Intl

32h 55m

2 stops

USM4:55 pmKo Samui

Apr 25

USM5:35 pmKo Samui

33h 30m

2 stops

IAD4:05 pmWashington, D.C. Dulles Intl

$1,494

Qatar Airways

Apr 10

IAD9:00 pmWashington, D.C. Dulles Intl

36h 25m

2 stops

USM8:25 pmKo Samui

Apr 24

USM6:00 amKo Samui

61h 40m

2 stops

IAD8:40 amWashington, D.C. Dulles Intl

$1,508

momondo Fare Finder

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

Fly from

Fly to

Route

Depart

Return

Price

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

mié. 5/6

3:10 pm-8:25 am

2 stops30h 15m

Ko Samui

jue. 5/14

6:00 am-9:45 am

2 stops38h 45m

$1,102

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

sáb. 5/9

1:20 pm-8:15 am

2 stops31h 55m

Ko Samui

dom. 5/17

6:00 am-11:35 am

2 stops40h 35m

$1,136

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

sáb. 5/9

3:10 pm-10:30 am

2 stops32h 20m

Ko Samui

dom. 5/17

6:00 am-9:45 am

2 stops38h 45m

$1,143

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

jue. 8/13

3:10 pm-7:10 am

2 stops29h 00m

Ko Samui

mié. 8/19

5:25 pm-9:45 am

2 stops27h 20m

$1,242

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

mié. 4/15

3:10 pm-7:30 am

2 stops29h 20m

Ko Samui

mié. 4/22

8:55 am-9:45 am

2 stops59h 50m

$1,261

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

vie. 4/17

3:10 pm-11:05 am

2 stops32h 55m

Ko Samui

vie. 4/24

9:00 pm-9:45 am

2 stops47h 45m

$1,267

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

vie. 4/24

3:10 pm-7:10 am

2 stops29h 00m

Ko Samui

lun. 5/4

7:00 pm-9:45 am

2 stops49h 45m

$1,272

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

sáb. 4/18

3:10 pm-8:25 am

2 stops30h 15m

Ko Samui

sáb. 4/25

6:00 am-9:45 am

2 stops38h 45m

$1,278

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

jue. 3/19

3:35 pm-7:30 am

2 stops28h 55m

Ko Samui

lun. 3/23

8:15 am-10:05 am

2 stops60h 50m

$1,340

Washington, D.C.Ko Samui

IAD - USM

IADUSM

Washington, D.C. Dulles Intl

vie. 4/10

1:20 pm-10:45 am

2 stops34h 25m

Ko Samui

mié. 4/22

1:30 pm-11:35 am

2 stops33h 05m

$1,352

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 12 resultsSorted by cheapest first

How to get the cheapest flight ticket from Washington, D.C. Dulles Intl Airport 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

Prices

Delays

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. Dulles Intl Airport 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. Dulles Intl Airport 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. Dulles Intl Airport to Ko Samui

Are you open to changing your travel dates? Check out the ideal times to fly from Washington, D.C. Dulles Intl Airport 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. Dulles Intl Airport to Ko Samui (IAD to USM) flight deals and tips

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

Fastest flight time	28h 55m
Direct flights	None

The fastest flight from Washington, D.C. Dulles Intl Airport to Ko Samui takes 28h 55m

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

Search flight deals

How far is Washington, D.C. Dulles Intl to Ko Samui by plane?
Ko Samui is 9077.6 mi away from Washington, D.C. Dulles Intl. By plane, this route typically takes 28h 55m.
When did momondo last update prices for flights from Washington, D.C. Dulles Intl Airport to Ko Samui Airport?
Prices for flights from Washington, D.C. Dulles Intl Airport to Ko Samui Airport refresh daily.
How old do you have to be to fly from Washington, D.C. Dulles Intl Airport to Ko Samui Airport?
Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Washington, D.C. Dulles Intl Airport to Ko Samui Airport.
What documentation or ID do you need to fly to Ko Samui Airport?
The travel and health documents required for your trip to Ko Samui Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Ko Samui Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

Ko Tao

Ko Pha Ngan

Khanom

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

We help find the flight that best suits your needs, momondo compares prices from hundreds of airlines and travel agents and helps you filter them to find the best flight from Washington, D.C. to Ko Samui for you.

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

momondo does allow users to show only those flights to Ko Samui from Washington, D.C. which offer a flexible booking policy as well as other useful filters and features.

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

Once you have performed a search in the form on the page, momondo provides useful filters and insights. We can show you the cheapest days and times to fly as well as help filter your options to help you make an informed choice when booking flights to Ko Samui from Washington, D.C..

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 offers price alerts on flights to Ko Samui from Washington, D.C.. After performing a search on this page you should be able to see the price alert set up feature. Simply provide a valid email address and momondo will instantly alert you when prices change.

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Cathay Pacific flights from Washington, D.C. Dulles Intl Airport to Ko Samui

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

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

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

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

Cheap Washington, D.C. Dulles Intl Airport to Ko Samui (IAD to USM) flight deals and tips

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List of cabin classes available on flights landing in Ko Samui. Availability may vary depending on flight origin and airline.

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