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SIR to STL: distance & flight time
Sion (Sion Airport) → St. Louis (St Louis Lambert International Airport)
4,677 mi
7,527 km · 4,064 nm
9h 38m
estimated nonstop flight time
-7h
time difference · heading northwest
See live SIR→STL fares Phone-only fares on this route — call free
Flight time details
4,677 miles nonstop takes roughly 9h 38m gate to gate, flying northwest. Add 45–90 minutes per connection if there's no nonstop service. Remember to factor the 7-hour time set-back when reading arrival times on your ticket.
The two airports
- SIR — Sion Airport · Sion, Switzerland
- STL — St Louis Lambert International Airport · St. Louis, 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 SIR
- AOT · Aosta Airport33 mi away
- QLS · Lausanne-Blécherette Airport41 mi away
- ZIN · Interlaken Air Base41 mi away
- MVV · Megève Airport43 mi away
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
Frequently asked questions
How far is SIR from STL?
The flight distance from Sion (SIR) to St. Louis (STL) 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 SIR to STL?
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 Sion and St. Louis?
St. Louis is 7 hours behind Sion.
What is the cheapest way to fly from SIR to STL?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on SIR–STL that never appear on search engines, with no booking fees.