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SEA to SIR: distance & flight time
Seattle (Seattle Tacoma International Airport) → Sion (Sion Airport)
5,286 mi
8,507 km · 4,593 nm
10h 50m
estimated nonstop flight time
+9h
time difference · heading northeast
See live SEA→SIR fares Phone-only fares on this route — call free
Flight time details
5,286 miles nonstop takes roughly 10h 50m gate to gate, flying northeast. Add 45–90 minutes per connection if there's no nonstop service. Remember to factor the 9-hour time gain when reading arrival times on your ticket.
The two airports
- SEA — Seattle Tacoma International Airport · Seattle, United States
- SIR — Sion Airport · Sion, Switzerland
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 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
Near SIR
- AOT · Aosta Airport33 mi away
- QLS · Lausanne-Blécherette Airport41 mi away
- ZIN · Interlaken Air Base41 mi away
- MVV · Megève Airport43 mi away
Frequently asked questions
How far is SEA from SIR?
The flight distance from Seattle (SEA) to Sion (SIR) is 5,286 miles (8,507 km, 4,593 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from SEA to SIR?
A nonstop flight takes about 10h 50m 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 Seattle and Sion?
Sion is 9 hours ahead of Seattle.
What is the cheapest way to fly from SEA to SIR?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on SEA–SIR that never appear on search engines, with no booking fees.