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ONT to GAI: distance & flight time
Ontario (Ontario International Airport) → Gaithersburg (Montgomery County Airpark)
2,251 mi
3,623 km · 1,956 nm
4h 53m
estimated nonstop flight time
+3h
time difference · heading east
See live ONT→GAI fares Phone-only fares on this route — call free
Flight time details
2,251 miles nonstop takes roughly 4h 53m gate to gate, flying east. Add 45–90 minutes per connection if there's no nonstop service. Remember to factor the 3-hour time gain when reading arrival times on your ticket.
The two airports
- ONT — Ontario International Airport · Ontario, United States
- GAI — Montgomery County Airpark · Gaithersburg, 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 ONT
- CCB · Cable Airport6 mi away
- CNO · Chino Airport6 mi away
- LAX · Los Angeles International Airport47 mi away
- RAL · Riverside Municipal Airport11 mi away
Near GAI
Frequently asked questions
How far is ONT from GAI?
The flight distance from Ontario (ONT) to Gaithersburg (GAI) is 2,251 miles (3,623 km, 1,956 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from ONT to GAI?
A nonstop flight takes about 4h 53m 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 Ontario and Gaithersburg?
Gaithersburg is 3 hours ahead of Ontario.
What is the cheapest way to fly from ONT to GAI?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on ONT–GAI that never appear on search engines, with no booking fees.