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ISN to USM: distance & flight time
Williston (Sloulin Field International Airport) → Ko Samui (Samui Airport)
8,194 mi
13,186 km · 7,120 nm
16h 32m
estimated nonstop flight time
+12h
time difference · heading northwest
See live ISN→USM fares Phone-only fares on this route — call free
Flight time details
8,194 miles nonstop takes roughly 16h 32m gate to gate, flying northwest. Add 45–90 minutes per connection if there's no nonstop service. Remember to factor the 12-hour time gain when reading arrival times on your ticket.
The two airports
- ISN — Sloulin Field International Airport · Williston, United States
- USM — Samui Airport · Ko Samui, Thailand
Distances are great-circle ("as the crow flies") — the same basis airlines use for frequent-flyer miles.
Alternate airports can cut this fare
Flying from or into a nearby airport is the #1 trick our agents use to beat online prices. Call and we'll compare every combination on one call.
Near ISN
- SDY · Sidney - Richland Regional Airport41 mi away
- YEN · Estevan Airport78 mi away
- OLF · L M Clayton Airport89 mi away
- GDV · Dawson Community Airport90 mi away
Near USM
- URT · Surat Thani Airport69 mi away
- NST · Nakhon Si Thammarat Airport70 mi away
- CJM · Chumphon Airport93 mi away
- UNN · Ranong Airport102 mi away
Frequently asked questions
How far is ISN from USM?
The flight distance from Williston (ISN) to Ko Samui (USM) is 8,194 miles (13,186 km, 7,120 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from ISN to USM?
A nonstop flight takes about 16h 32m gate to gate. Actual time varies with winds, routing and season — eastbound transatlantic flights, for example, are usually faster than the return.
What is the time difference between Williston and Ko Samui?
Ko Samui is 12 hours ahead of Williston.
What is the cheapest way to fly from ISN to USM?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on ISN–USM that never appear on search engines, with no booking fees.