The flight distance from Tribhuvan International Airport (KTM) in Kathmandu, Nepal to Boulder Municipal Airport (WBU) in Boulder, United States is 12,403 kilometers (7,707 miles / 6,697 nautical miles). The estimated flight time for this route is approximately 16h, flying north at a heading of 9°.

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 Nepal with United States. It is an intercontinental flight between Asia and North America. Travelers should check visa requirements, customs regulations, and any travel advisories before booking.

Time zone information: When it's 20:23 in Kathmandu, it's 08:38 in Boulder. With a 11.75-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 Boulder (WBU) to Kathmandu (KTM) follows a heading of 350° (north). Actual flight times may vary depending on wind conditions, air traffic, and the specific aircraft used.

For more information about these airports, visit the Tribhuvan International Airport (KTM) and Boulder Municipal Airport (WBU) detail pages, or use our flight duration calculator to compare other routes.