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KOS to GAI: distance & flight time
Sihanoukville (Sihanoukville International Airport) → Gaithersburg (Montgomery County Airpark)
8,999 mi
14,483 km · 7,820 nm
18h 7m
estimated nonstop flight time
-11h
time difference · heading north
See live KOS→GAI fares Phone-only fares on this route — call free
Flight time details
8,999 miles nonstop takes roughly 18h 7m 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
- GAI — Montgomery County Airpark · Gaithersburg, 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
Near GAI
Frequently asked questions
How far is KOS from GAI?
The flight distance from Sihanoukville (KOS) to Gaithersburg (GAI) is 8,999 miles (14,483 km, 7,820 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from KOS to GAI?
A nonstop flight takes about 18h 7m 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 Gaithersburg?
Gaithersburg is 11 hours behind Sihanoukville.
What is the cheapest way to fly from KOS to GAI?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on KOS–GAI that never appear on search engines, with no booking fees.