# Distance from Sofia (SOF) to Boulder (WBU)

> 9,466 km · estimated flight time 12h · Ultra-long-haul route.

## Summary

- **Distance**: 9,466 km / 5,882 mi / 5,111 nm
- **Estimated flight time**: 12h
- **Heading**: 323° (northwest)
- **Return heading**: 35° (northeast)
- **Classification**: Ultra-long-haul
- **Type**: International (Bulgaria) → United States
- **Intercontinental**: Europe → North America
- **Time difference**: -9h (When it's 23:25 in Sofia, it's 14:25 in Boulder)
- **Elevation difference**: 3,546 ft (WBU is higher than SOF)

## Airports

### [Sofia Airport (SOF)](https://flightduration.online/airport/sof-sofia-sofia-airport/1ef266df-436b-611c-bff1-06bb2780ed98)

- City: Sofia, Bulgaria
- ICAO: LBSF
- Timezone: Europe/Sofia
- Coordinates: 42.700000, 23.410000
- Elevation: 1,742 ft

### [Boulder Municipal Airport (WBU)](https://flightduration.online/airport/wbu-boulder-boulder-municipal-airport/1ef266df-1024-68d0-9f40-06bb2780ed98)

- City: Boulder, United States
- ICAO: KBDU
- Timezone: America/Denver
- Coordinates: 40.040000, -105.230000
- Elevation: 5,288 ft

## Route notes

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.

Time-zone information: When it's 23:25 in Sofia, it's 14:25 in Boulder.
With a 9-hour time difference, expect significant jet lag.

## Related

- [Sofia Airport (SOF)](https://flightduration.online/airport/sof-sofia-sofia-airport/1ef266df-436b-611c-bff1-06bb2780ed98)
- [Boulder Municipal Airport (WBU)](https://flightduration.online/airport/wbu-boulder-boulder-municipal-airport/1ef266df-1024-68d0-9f40-06bb2780ed98)
- [Flight duration calculator](/#calculator)