Distance From Roberts International Airport to Ontario International Airport, ROB - ONT Distance

The distance from Roberts International Airport (ROB) to Ontario International Airport (ONT) is 6948 miles or 11182 kilometers or 6034 nautical miles.

The distance shown below is direct flight distance between airports. Straight-line distance does not account for the surface between the two points. It is the distance a bird or airplane would travel between the two points when flying above the surface. The straight line distance is the direct route between two points, regardless of whether or not there are roads that connect them.

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How long does it take to travel from Monrovia ( Liberia ) to Ontario ( United States )?

A one-way nonstop (direct) flight between Monrovia and Ontario takes around 15 hours 58 minutes.

Estimated flight time from Roberts International Airport, Monrovia, Liberia to Ontario International Airport, Ontario, United States is 15 hours 58 minutes under avarage conditions. Your actual flying time may vary depending on wind direction/speed or weather conditions. This calculation does not include the departure and landing times of the aircraft. In addition, it does not cover the person identity check, ticket check-in and baggage collection times at the airport.

Travel Distance Between the Airports • ROB - ONT

Kilometers		11182 km
Statute Miles		6948 miles
Nautical Miles		6034 nm
Avg. Time of Flight		15 hours 58 minutes

Roberts International Airport to Ontario International Airport Flight Route Map - ROB to ONT Flight Path

Location of Roberts International Airport & Ontario International Airport is given below.
Click the map to view Monrovia to Ontario nonstop flight path and travel direction.

Click to see flight route on Google Map between Monrovia, Liberia and Ontario, United States. .

Nonstop flight route between Monrovia, Liberia and Ontario, United States.

Time Difference Between the Airports • ROB - ONT

Time difference between Monrovia (Liberia) and Ontario (United States) is 7 Hours.
Ontario time is 7 Hours behind Monrovia.

Location	Local Time
Monrovia (Liberia)	2026-07-28, 19:41:26 GMT
Ontario (United States)	2026-07-28, 12:41:26 PDT

Why should you arrive 3 hours before international flight? Flyers who are traveling to an international destination should arrive at the airport earlier than domestic flyers. This is because international flights can have additional check-in requirements, like passport verification, that need to be completed before you receive your boarding pass.

Origin

Roberts International Airport (ROB / GLRB) Monrovia, Liberia

Destination

Ontario International Airport (ONT / KONT) Ontario, United States