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STL to SIR: distance & flight time
St. Louis (St Louis Lambert International Airport) → Sion (Sion Airport)
4,677 mi
7,527 km · 4,064 nm
9h 38m
estimated nonstop flight time
+7h
time difference · heading northeast
See live STL→SIR fares Phone-only fares on this route — call free
Flight time details
4,677 miles nonstop takes roughly 9h 38m gate to gate, flying northeast. Add 45–90 minutes per connection if there's no nonstop service. Remember to factor the 7-hour time gain when reading arrival times on your ticket.
The two airports
- STL — St Louis Lambert International Airport · St. Louis, 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 STL
- SUS · Spirit of St Louis Airport16 mi away
- ALN · St Louis Regional Airport20 mi away
- BLV · Scott AFB/Midamerica Airport32 mi away
- SPI · Abraham Lincoln Capital Airport84 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 STL from SIR?
The flight distance from St. Louis (STL) to Sion (SIR) is 4,677 miles (7,527 km, 4,064 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from STL to SIR?
A nonstop flight takes about 9h 38m 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 St. Louis and Sion?
Sion is 7 hours ahead of St. Louis.
What is the cheapest way to fly from STL to SIR?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on STL–SIR that never appear on search engines, with no booking fees.