The flight distance from St Louis Regional Airport (ALN) in Alton/St Louis, United States to Incheon International Airport (ICN) in Seoul, South Korea is 10,740 kilometers (6,673 miles / 5,799 nautical miles). The estimated flight time for this route is approximately 14h, flying north northwest at a heading of 332°.

This is an ultra-long-haul route, one of the longest in aviation. It requires wide-body aircraft with extended range capability such as the Airbus A350-900ULR or Boeing 777-200LR. Passengers should prepare for an extended flight with multiple meal services.

This is an international route connecting United States with South Korea. It is an intercontinental flight between North America and Asia. Travelers should check visa requirements, customs regulations, and any travel advisories before booking.

Time zone information: When it's 12:47 in Alton/St Louis, it's 03:47 in Seoul. With a 15-hour time difference, travelers should plan for significant jet lag. It typically takes one day per hour of time difference to fully adjust.

The return flight from Seoul (ICN) to Alton/St Louis (ALN) follows a heading of 28° (north northeast). Actual flight times may vary depending on wind conditions, air traffic, and the specific aircraft used.

For more information about these airports, visit the St Louis Regional Airport (ALN) and Incheon International Airport (ICN) detail pages, or use our flight duration calculator to compare other routes.