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ISN to PRM: distance & flight time
Williston (Sloulin Field International Airport) → Portimao (Portimão Airport)
4,576 mi
7,364 km · 3,976 nm
9h 26m
estimated nonstop flight time
+6h
time difference · heading northeast
See live ISN→PRM fares Phone-only fares on this route — call free
Flight time details
4,576 miles nonstop takes roughly 9h 26m gate to gate, flying northeast. Add 45–90 minutes per connection if there's no nonstop service. Remember to factor the 6-hour time gain when reading arrival times on your ticket.
The two airports
- ISN — Sloulin Field International Airport · Williston, United States
- PRM — Portimão Airport · Portimao, Portugal
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 PRM
- FAO · Faro Airport35 mi away
- BYJ · Beja Airport / Airbase73 mi away
- CAT · Cascais Airport117 mi away
- LIS · Humberto Delgado Airport (Lisbon Portela Airport)117 mi away
Frequently asked questions
How far is ISN from PRM?
The flight distance from Williston (ISN) to Portimao (PRM) is 4,576 miles (7,364 km, 3,976 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from ISN to PRM?
A nonstop flight takes about 9h 26m 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 time difference between Williston and Portimao?
Portimao is 6 hours ahead of Williston.
What is the cheapest way to fly from ISN to PRM?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on ISN–PRM that never appear on search engines, with no booking fees.