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HLN to REP: distance & flight time
Helena (Helena Regional Airport) → Siem-reap (Siem Reap International Airport)
7,734 mi
12,446 km · 6,720 nm
15h 38m
estimated nonstop flight time
+13h
time difference · heading northwest
See live HLN→REP fares Phone-only fares on this route — call free
Flight time details
7,734 miles nonstop takes roughly 15h 38m gate to gate, flying northwest. Add 45–90 minutes per connection if there's no nonstop service. Remember to factor the 13-hour time gain when reading arrival times on your ticket.
The two airports
- HLN — Helena Regional Airport · Helena, United States
- REP — Siem Reap International Airport · Siem-reap, Cambodia
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 HLN
- BTM · Bert Mooney Airport51 mi away
- GTF · Great Falls International Airport67 mi away
- BZN · Gallatin Field70 mi away
- LVM · Mission Field97 mi away
Near REP
- BBM · Battambang Airport45 mi away
- KZC · Kampong Chhnang Airport95 mi away
- PXR · Surin Airport103 mi away
- TDX · Trat Airport128 mi away
Frequently asked questions
How far is HLN from REP?
The flight distance from Helena (HLN) to Siem-reap (REP) is 7,734 miles (12,446 km, 6,720 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from HLN to REP?
A nonstop flight takes about 15h 38m 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 Helena and Siem-reap?
Siem-reap is 13 hours ahead of Helena.
What is the cheapest way to fly from HLN to REP?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on HLN–REP that never appear on search engines, with no booking fees.