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YSL to BFI: distance & flight time
St Leonard (St Leonard Airport) → Seattle (Boeing Field King County International Airport)
2,496 mi
4,017 km · 2,169 nm
5h 22m
estimated nonstop flight time
—
time difference · heading west
See live YSL→BFI fares Phone-only fares on this route — call free
Flight time details
2,496 miles nonstop takes roughly 5h 22m gate to gate, flying west. 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
- YSL — St Leonard Airport · St Leonard, Canada
- 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 YSL
- CAR · Caribou Municipal Airport22 mi away
- WFK · Northern Aroostook Regional Airport24 mi away
- PQI · Northern Maine Regional Airport at Presque Isle34 mi away
- HUL · Houlton International Airport71 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 YSL from BFI?
The flight distance from St Leonard (YSL) to Seattle (BFI) is 2,496 miles (4,017 km, 2,169 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from YSL to BFI?
A nonstop flight takes about 5h 22m 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 YSL to BFI?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on YSL–BFI that never appear on search engines, with no booking fees.