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KOS to IAD: distance & flight time
Sihanoukville (Sihanoukville International Airport) → Washington (Washington Dulles International Airport)
9,014 mi
14,507 km · 7,833 nm
18h 9m
estimated nonstop flight time
-11h
time difference · heading north
See live KOS→IAD fares Phone-only fares on this route — call free
Flight time details
9,014 miles nonstop takes roughly 18h 9m gate to gate, flying north. Add 45–90 minutes per connection if there's no nonstop service. Remember to factor the 11-hour time set-back when reading arrival times on your ticket.
The two airports
- KOS — Sihanoukville International Airport · Sihanoukville, Cambodia
- IAD — Washington Dulles International Airport · Washington, United States
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 KOS
- PQC · Phu Quoc International Airport37 mi away
- PNH · Phnom Penh International Airport106 mi away
- VKG · Rach Gia Airport110 mi away
- KZC · Kampong Chhnang Airport132 mi away
Frequently asked questions
How far is KOS from IAD?
The flight distance from Sihanoukville (KOS) to Washington (IAD) is 9,014 miles (14,507 km, 7,833 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from KOS to IAD?
A nonstop flight takes about 18h 9m 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 Sihanoukville and Washington?
Washington is 11 hours behind Sihanoukville.
What is the cheapest way to fly from KOS to IAD?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on KOS–IAD that never appear on search engines, with no booking fees.