Need help booking?
Unpublished phone-only deals available
OSN to SEA: distance & flight time
Osan (Osan Air Base) → Seattle (Seattle Tacoma International Airport)
5,202 mi
8,372 km · 4,520 nm
10h 40m
estimated nonstop flight time
-16h
time difference · heading northeast
See live OSN→SEA fares Phone-only fares on this route — call free
Flight time details
5,202 miles nonstop takes roughly 10h 40m gate to gate, flying northeast. Add 45–90 minutes per connection if there's no nonstop service. Remember to factor the 16-hour time set-back when reading arrival times on your ticket.
The two airports
- OSN — Osan Air Base · Osan, South Korea
- SEA — Seattle Tacoma International Airport · Seattle, 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 OSN
- ICN · Incheon International Airport41 mi away
- SWU · Suwon Airport10 mi away
- SSN · Seoul Air Base (K-16)25 mi away
- GMP · Gimpo International Airport35 mi away
Near SEA
- RNT · Renton Municipal Airport5 mi away
- BFI · Boeing Field King County International Airport6 mi away
- TIW · Tacoma Narrows Airport18 mi away
- PWT · Bremerton National Airport21 mi away
Frequently asked questions
How far is OSN from SEA?
The flight distance from Osan (OSN) to Seattle (SEA) is 5,202 miles (8,372 km, 4,520 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from OSN to SEA?
A nonstop flight takes about 10h 40m 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 Osan and Seattle?
Seattle is 16 hours behind Osan.
What is the cheapest way to fly from OSN to SEA?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on OSN–SEA that never appear on search engines, with no booking fees.