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KLS to BFI: distance & flight time
Kelso (Southwest Washington Regional Airport) → Seattle (Boeing Field King County International Airport)
102 mi
163 km · 88 nm
44m
estimated nonstop flight time
Same time
time difference · heading north
See live KLS→BFI fares Phone-only fares on this route — call free
Flight time details
102 miles nonstop takes roughly 44m 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
- KLS — Southwest Washington Regional Airport · Kelso, United States
- 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 KLS
- PDX · Portland International Airport39 mi away
- CLS · Chehalis Centralia Airport39 mi away
- HIO · Portland Hillsboro Airport40 mi away
- TTD · Portland Troutdale Airport46 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 KLS from BFI?
The flight distance from Kelso (KLS) to Seattle (BFI) is 102 miles (163 km, 88 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from KLS to BFI?
A nonstop flight takes about 44m 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 cheapest way to fly from KLS to BFI?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on KLS–BFI that never appear on search engines, with no booking fees.