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KOS to HLN: distance & flight time
Sihanoukville (Sihanoukville International Airport) → Helena (Helena Regional Airport)
7,915 mi
12,738 km · 6,878 nm
15h 59m
estimated nonstop flight time
-13h
time difference · heading northeast
See live KOS→HLN fares Phone-only fares on this route — call free
Flight time details
7,915 miles nonstop takes roughly 15h 59m gate to gate, flying northeast. Add 45–90 minutes per connection if there's no nonstop service. Remember to factor the 13-hour time set-back when reading arrival times on your ticket.
The two airports
- KOS — Sihanoukville International Airport · Sihanoukville, Cambodia
- HLN — Helena Regional Airport · Helena, 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 HLN
- BTM · Bert Mooney Airport51 mi away
- GTF · Great Falls International Airport67 mi away
- BZN · Gallatin Field70 mi away
- LVM · Mission Field97 mi away
Frequently asked questions
How far is KOS from HLN?
The flight distance from Sihanoukville (KOS) to Helena (HLN) is 7,915 miles (12,738 km, 6,878 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from KOS to HLN?
A nonstop flight takes about 15h 59m 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 Helena?
Helena is 13 hours behind Sihanoukville.
What is the cheapest way to fly from KOS to HLN?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on KOS–HLN that never appear on search engines, with no booking fees.