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HLN to OPO: distance & flight time
Helena (Helena Regional Airport) → Porto (Francisco de Sá Carneiro Airport)
4,759 mi
7,660 km · 4,136 nm
9h 48m
estimated nonstop flight time
+7h
time difference · heading northeast
See live HLN→OPO fares Phone-only fares on this route — call free
Flight time details
4,759 miles nonstop takes roughly 9h 48m 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
- HLN — Helena Regional Airport · Helena, 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 HLN
- BTM · Bert Mooney Airport51 mi away
- GTF · Great Falls International Airport67 mi away
- BZN · Gallatin Field70 mi away
- LVM · Mission Field97 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 HLN from OPO?
The flight distance from Helena (HLN) to Porto (OPO) is 4,759 miles (7,660 km, 4,136 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from HLN to OPO?
A nonstop flight takes about 9h 48m 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 Helena and Porto?
Porto is 7 hours ahead of Helena.
What is the cheapest way to fly from HLN to OPO?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on HLN–OPO that never appear on search engines, with no booking fees.