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USN to STL: distance & flight time
Ulsan (Ulsan Airport) → St. Louis (St Louis Lambert International Airport)
6,709 mi
10,796 km · 5,830 nm
13h 37m
estimated nonstop flight time
-14h
time difference · heading northeast
See live USN→STL fares Phone-only fares on this route — call free
Flight time details
6,709 miles nonstop takes roughly 13h 37m gate to gate, flying northeast. Add 45–90 minutes per connection if there's no nonstop service. Remember to factor the 14-hour time set-back when reading arrival times on your ticket.
The two airports
- USN — Ulsan Airport · Ulsan, South Korea
- 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 USN
- KPO · Pohang Airport (G-815/K-3)28 mi away
- PUS · Gimhae International Airport37 mi away
- TAE · Daegu Airport44 mi away
- CHF · Jinhae Airbase/Airport (G-813/K-10)48 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 USN from STL?
The flight distance from Ulsan (USN) to St. Louis (STL) is 6,709 miles (10,796 km, 5,830 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from USN to STL?
A nonstop flight takes about 13h 37m gate to gate. Actual time varies with winds, routing and season — eastbound transatlantic flights, for example, are usually faster than the return.
Are there nonstop flights from USN to STL?
Nonstop service on USN–STL depends on the season and the day of week. Run the fare search on this page with the nonstop filter applied to see current direct options; when there is no nonstop, a single connection through a carrier hub adds roughly 2–4 hours to the 13h 37m nonstop estimate.
What is the time difference between Ulsan and St. Louis?
St. Louis is 14 hours behind Ulsan.
What is the cheapest way to fly from USN to STL?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on USN–STL that never appear on search engines, with no booking fees.
Why are some USN to STL fares phone-only?
Consolidator contracts let us sell certain USN–STL tickets below the price airlines permit us to publish online, so those fares can only be quoted over the phone. Call the travel desk and an agent will check phone-only inventory for your dates.