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KSO to BFI: distance & flight time
Kastoria (Kastoria National Airport) → Seattle (Boeing Field King County International Airport)
5,961 mi
9,593 km · 5,180 nm
12h 9m
estimated nonstop flight time
-10h
time difference · heading northwest
See live KSO→BFI fares Phone-only fares on this route — call free
Flight time details
5,961 miles nonstop takes roughly 12h 9m gate to gate, flying northwest. Add 45–90 minutes per connection if there's no nonstop service. Remember to factor the 10-hour time set-back when reading arrival times on your ticket.
The two airports
- KSO — Kastoria National Airport · Kastoria, Greece
- BFI — Boeing Field King County 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 KSO
- KZI · Filippos Airport31 mi away
- IOA · Ioannina Airport57 mi away
- OHD · Ohrid St. Paul the Apostle Airport58 mi away
- LRA · Larisa Airport83 mi away
Near BFI
- SEA · Seattle Tacoma International Airport6 mi away
- RNT · Renton Municipal Airport5 mi away
- PWT · Bremerton National Airport22 mi away
- TIW · Tacoma Narrows Airport22 mi away
Frequently asked questions
How far is KSO from BFI?
The flight distance from Kastoria (KSO) to Seattle (BFI) is 5,961 miles (9,593 km, 5,180 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from KSO to BFI?
A nonstop flight takes about 12h 9m 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 Kastoria and Seattle?
Seattle is 10 hours behind Kastoria.
What is the cheapest way to fly from KSO to BFI?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on KSO–BFI that never appear on search engines, with no booking fees.