The flight distance from St Louis Regional Airport (ALN) in Alton/St Louis, United States to Tan Son Nhat International Airport (SGN) in Ho Chi Minh City, Vietnam is 14,223 kilometers (8,838 miles / 7,680 nautical miles). The estimated flight time for this route is approximately 18h, flying north northwest at a heading of 339°.

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 Vietnam. 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 10:34 in Alton/St Louis, it's 23:34 in Ho Chi Minh City. With a 13-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 Ho Chi Minh City (SGN) to Alton/St Louis (ALN) follows a heading of 16° (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 Tan Son Nhat International Airport (SGN) detail pages, or use our flight duration calculator to compare other routes.