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GAI to ONT: distance & flight time
Gaithersburg (Montgomery County Airpark) → Ontario (Ontario International Airport)
2,251 mi
3,623 km · 1,956 nm
4h 53m
estimated nonstop flight time
-3h
time difference · heading west
See live GAI→ONT fares Phone-only fares on this route — call free
Flight time details
2,251 miles nonstop takes roughly 4h 53m gate to gate, flying west. Add 45–90 minutes per connection if there's no nonstop service. Remember to factor the 3-hour time set-back when reading arrival times on your ticket.
The two airports
- GAI — Montgomery County Airpark · Gaithersburg, United States
- ONT — Ontario International Airport · Ontario, 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 GAI
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
Frequently asked questions
How far is GAI from ONT?
The flight distance from Gaithersburg (GAI) to Ontario (ONT) 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 GAI to ONT?
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 Gaithersburg and Ontario?
Ontario is 3 hours behind Gaithersburg.
What is the cheapest way to fly from GAI to ONT?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on GAI–ONT that never appear on search engines, with no booking fees.