The flight distance from Helena Regional Airport (HLN) in Helena, United States to Sofia Airport (SOF) in Sofia, Bulgaria is 9,155 kilometers (5,689 miles / 4,943 nautical miles). The estimated flight time for this route is approximately 12h, flying north northeast at a heading of 31°.

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 Bulgaria. It is an intercontinental flight between North America and Europe. Travelers should check visa requirements, customs regulations, and any travel advisories before booking.

Time zone information: When it's 11:03 in Helena, it's 20:03 in Sofia. With a 9-hour time difference, travelers should plan for significant jet lag. It typically takes one day per hour of time difference to fully adjust.

There is a significant elevation difference of 2,135 feet between the two airports. Sofia Airport sits lower than Helena Regional Airport.

The return flight from Sofia (SOF) to Helena (HLN) follows a heading of 331° (north northwest). Actual flight times may vary depending on wind conditions, air traffic, and the specific aircraft used.

For more information about these airports, visit the Helena Regional Airport (HLN) and Sofia Airport (SOF) detail pages, or use our flight duration calculator to compare other routes.