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ISN to SOF: distance & flight time
Williston (Sloulin Field International Airport) → Sofia (Sofia Airport)
5,381 mi
8,659 km · 4,676 nm
11h 1m
estimated nonstop flight time
+8h
time difference · heading northeast
See live ISN→SOF fares Phone-only fares on this route — call free
Flight time details
5,381 miles nonstop takes roughly 11h 1m gate to gate, flying northeast. Add 45–90 minutes per connection if there's no nonstop service. Remember to factor the 8-hour time gain when reading arrival times on your ticket.
The two airports
- ISN — Sloulin Field International Airport · Williston, United States
- SOF — Sofia Airport · Sofia, Bulgaria
Distances are great-circle ("as the crow flies") — the same basis airlines use for frequent-flyer miles.
Alternate airports can cut this fare
Flying from or into a nearby airport is the #1 trick our agents use to beat online prices. Call and we'll compare every combination on one call.
Near ISN
- SDY · Sidney - Richland Regional Airport41 mi away
- YEN · Estevan Airport78 mi away
- OLF · L M Clayton Airport89 mi away
- GDV · Dawson Community Airport90 mi away
Near SOF
- PDV · Plovdiv International Airport85 mi away
- INI · Nis Airport90 mi away
- SKP · Skopje Alexander the Great Airport105 mi away
- CRA · Craiova Airport115 mi away
Frequently asked questions
How far is ISN from SOF?
The flight distance from Williston (ISN) to Sofia (SOF) is 5,381 miles (8,659 km, 4,676 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from ISN to SOF?
A nonstop flight takes about 11h 1m gate to gate. Actual time varies with winds, routing and season — eastbound transatlantic flights, for example, are usually faster than the return.
Are there nonstop flights from ISN to SOF?
Nonstop service on ISN–SOF depends on the season and the day of week. Run the fare search on this page with the nonstop filter applied to see current direct options; when there is no nonstop, a single connection through a carrier hub adds roughly 2–4 hours to the 11h 1m nonstop estimate.
What is the time difference between Williston and Sofia?
Sofia is 8 hours ahead of Williston.
What is the cheapest way to fly from ISN to SOF?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on ISN–SOF that never appear on search engines, with no booking fees.
Why are some ISN to SOF fares phone-only?
Consolidator contracts let us sell certain ISN–SOF tickets below the price airlines permit us to publish online, so those fares can only be quoted over the phone. Call the travel desk and an agent will check phone-only inventory for your dates.