Distance From Sion Airport to St Louis Lambert International Airport, SIR - STL Distance

The distance from Sion Airport (SIR) to St Louis Lambert International Airport (STL) is 4677 miles or 7527 kilometers or 4062 nautical miles.

The distance shown below is direct flight distance between airports. Straight-line distance does not account for the surface between the two points. It is the distance a bird or airplane would travel between the two points when flying above the surface. The straight line distance is the direct route between two points, regardless of whether or not there are roads that connect them.

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How long does it take to travel from Sion ( Switzerland ) to St Louis ( United States )?

A one-way nonstop (direct) flight between Sion and St Louis takes around 10 hours 45 minutes.

Estimated flight time from Sion Airport, Sion, Switzerland to St Louis Lambert International Airport, St Louis, United States is 10 hours 45 minutes under avarage conditions. Your actual flying time may vary depending on wind direction/speed or weather conditions. This calculation does not include the departure and landing times of the aircraft. In addition, it does not cover the person identity check, ticket check-in and baggage collection times at the airport.

Travel Distance Between the Airports • SIR - STL

Kilometers		7527 km
Statute Miles		4677 miles
Nautical Miles		4062 nm
Avg. Time of Flight		10 hours 45 minutes

Sion Airport to St Louis Lambert International Airport Flight Route Map - SIR to STL Flight Path

Location of Sion Airport & St Louis Lambert International Airport is given below.
Click the map to view Sion to St Louis nonstop flight path and travel direction.

Click to see flight route on Google Map between Sion, Switzerland and St Louis, United States. .

Nonstop flight route between Sion, Switzerland and St Louis, United States.

Time Difference Between the Airports • SIR - STL

Time difference between Sion (Switzerland) and St Louis (United States) is 6 Hours.
St Louis time is 6 Hours behind Sion.

Location	Local Time
Sion (Switzerland)	2025-12-05, 14:09:35 CET
St Louis (United States)	2025-12-05, 08:09:35 EST

Why should you arrive 3 hours before international flight? Flyers who are traveling to an international destination should arrive at the airport earlier than domestic flyers. This is because international flights can have additional check-in requirements, like passport verification, that need to be completed before you receive your boarding pass.

Origin

Sion Airport (SIR / LSGS) Sion, Switzerland

Destination

St Louis Lambert International Airport (STL / KSTL) St Louis, United States