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GTF to OPO: distance & flight time
Great Falls (Great Falls International Airport) → Porto (Francisco de Sá Carneiro Airport)
4,699 mi
7,563 km · 4,084 nm
9h 41m
estimated nonstop flight time
+7h
time difference · heading northeast
See live GTF→OPO fares Phone-only fares on this route — call free
Flight time details
4,699 miles nonstop takes roughly 9h 41m gate to gate, flying northeast. Add 45–90 minutes per connection if there's no nonstop service. Remember to factor the 7-hour time gain when reading arrival times on your ticket.
The two airports
- GTF — Great Falls International Airport · Great Falls, United States
- OPO — Francisco de Sá Carneiro Airport · Porto, 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 GTF
- HLN · Helena Regional Airport67 mi away
- CTB · Cut Bank International Airport91 mi away
- LWT · Lewistown Municipal Airport94 mi away
- HVR · Havre City County Airport104 mi away
Near OPO
- BGZ · Braga Municipal Aerodrome26 mi away
- VRL · Vila Real Airport50 mi away
- VSE · Aerodromo Goncalves Lobato (Viseu Airport)55 mi away
- VGO · Vigo Airport68 mi away
Frequently asked questions
How far is GTF from OPO?
The flight distance from Great Falls (GTF) to Porto (OPO) is 4,699 miles (7,563 km, 4,084 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from GTF to OPO?
A nonstop flight takes about 9h 41m 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 Great Falls and Porto?
Porto is 7 hours ahead of Great Falls.
What is the cheapest way to fly from GTF to OPO?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on GTF–OPO that never appear on search engines, with no booking fees.