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SEP to ISN: distance & flight time
Stephenville (Stephenville Clark Regional Airport) → Williston (Sloulin Field International Airport)
1,139 mi
1,833 km · 990 nm
2h 57m
estimated nonstop flight time
Same time
time difference · heading north
See live SEP→ISN fares Phone-only fares on this route — call free
Flight time details
1,139 miles nonstop takes roughly 2h 57m gate to gate, flying north. Add 45–90 minutes per connection if there's no nonstop service. Both airports share the same local time, so schedules read exactly as flown.
The two airports
- SEP — Stephenville Clark Regional Airport · Stephenville, United States
- ISN — Sloulin Field International Airport · Williston, United States
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 SEP
- MWL · Mineral Wells Airport40 mi away
- DFW · Dallas Fort Worth International Airport81 mi away
- BKD · Stephens County Airport54 mi away
- FWH · NAS Fort Worth JRB/Carswell Field57 mi away
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
Frequently asked questions
How far is SEP from ISN?
The flight distance from Stephenville (SEP) to Williston (ISN) is 1,139 miles (1,833 km, 990 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from SEP to ISN?
A nonstop flight takes about 2h 57m gate to gate. Actual time varies with winds, routing and season — eastbound transatlantic flights, for example, are usually faster than the return.
What is the cheapest way to fly from SEP to ISN?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on SEP–ISN that never appear on search engines, with no booking fees.