The flight distance from Sofia Airport (SOF) in Sofia, Bulgaria to Boulder Municipal Airport (WBU) in Boulder, United States is 9,466 kilometers (5,882 miles / 5,111 nautical miles). The estimated flight time for this route is approximately 12h, flying northwest at a heading of 323°.

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

Time zone information: When it's 01:53 in Sofia, it's 16:53 in Boulder. 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 3,546 feet between the two airports. Boulder Municipal Airport sits higher than Sofia Airport. Travelers arriving at the higher-elevation airport should be aware of potential altitude effects.

The return flight from Boulder (WBU) to Sofia (SOF) follows a heading of 35° (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 Sofia Airport (SOF) and Boulder Municipal Airport (WBU) detail pages, or use our flight duration calculator to compare other routes.