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KSJ to BFI: distance & flight time
Kasos (Kasos Airport) → Seattle (Boeing Field King County International Airport)
6,397 mi
10,295 km · 5,559 nm
13h 1m
estimated nonstop flight time
-10h
time difference · heading north
See live KSJ→BFI fares Phone-only fares on this route — call free
Flight time details
6,397 miles nonstop takes roughly 13h 1m gate to gate, flying north. 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
- KSJ — Kasos Airport · Kasos, 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 KSJ
- AOK · Karpathos Airport13 mi away
- JSH · Sitia Airport48 mi away
- JTY · Astypalaia Airport85 mi away
- KGS · Kos Airport95 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 KSJ from BFI?
The flight distance from Kasos (KSJ) to Seattle (BFI) is 6,397 miles (10,295 km, 5,559 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from KSJ to BFI?
A nonstop flight takes about 13h 1m 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 Kasos and Seattle?
Seattle is 10 hours behind Kasos.
What is the cheapest way to fly from KSJ to BFI?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on KSJ–BFI that never appear on search engines, with no booking fees.