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KOS to CEI: distance & flight time
Sihanoukville (Sihanoukville International Airport) → Chiang Rai (Chiang Rai International Airport)
694 mi
1,117 km · 603 nm
1h 59m
estimated nonstop flight time
Same time
time difference · heading north
See live KOS→CEI fares Phone-only fares on this route — call free
Flight time details
694 miles nonstop takes roughly 1h 59m gate to gate, flying north. Add 45–90 minutes per connection if there's no nonstop service. Both airports share the same local time, so schedules read exactly as flown.
The two airports
- KOS — Sihanoukville International Airport · Sihanoukville, Cambodia
- CEI — Chiang Rai International Airport · Chiang Rai, 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 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 CEI
- THL · Tachileik Airport37 mi away
- HOE · Ban Huoeisay Airport42 mi away
- MOG · Mong Hsat Airport56 mi away
- KET · Kengtung Airport95 mi away
Frequently asked questions
How far is KOS from CEI?
The flight distance from Sihanoukville (KOS) to Chiang Rai (CEI) is 694 miles (1,117 km, 603 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from KOS to CEI?
A nonstop flight takes about 1h 59m gate to gate. Actual time varies with winds, routing and season — eastbound transatlantic flights, for example, are usually faster than the return.
Are there nonstop flights from KOS to CEI?
Nonstop service on KOS–CEI depends on the season and the day of week. Run the fare search on this page with the nonstop filter applied to see current direct options; when there is no nonstop, a single connection through a carrier hub adds roughly 2–4 hours to the 1h 59m nonstop estimate.
What is the cheapest way to fly from KOS to CEI?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on KOS–CEI that never appear on search engines, with no booking fees.
Why are some KOS to CEI fares phone-only?
Consolidator contracts let us sell certain KOS–CEI tickets below the price airlines permit us to publish online, so those fares can only be quoted over the phone. Call the travel desk and an agent will check phone-only inventory for your dates.