Cheap Flight Tickets from Ontario (ONT) to London (LHR), Starting at $374

Good to Know: Cheapest and Fastest ONT - LHR Flights

Useful information for finding best airline tickets from Ontario International to London Heathrow on your next trip.

Cheapest Round Trip Flight

$876

AA American Airlines • 1 stop • 23h 51m

Aug 28 – Sep 04

The cheapest round trip flight from Ontario to London (ONT-LHR-ONT) is currently $876

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Fastest Flight

20h 54m

The fastest nonstop flight from Ontario to London (ONT-LHR) takes 20h 54m

Top Airlines Flying from Ontario to London

Delta Airline, DL

Delta Airlines

American Airlines, AA

American Airlines

United Airlines, UA

United Airlines

Alaska Airlines -AS

Alaska Airlines

Latest Flight Deals from Ontario (ONT) to London (LHR)

Compare and book low fare round-trip air tickets from Ontario to London. Ideal for travelers with confirmed return itineraries.

Aug 28 - Sep 04, Economy
AA
Ontario → London
23h 51m
10:29 AM - 9:00 AM • 1 stop
AA
Ontario → London
23h 45m
12:00 PM - 6:25 PM • 1 stop
$876
American Airlines
Sep 07 - Sep 17, Economy
DL
Ontario → London
25h 20m
7:05 AM - 6:25 AM • 1 stop
DL
Ontario → London
22h
6:30 AM - 11:50 AM • 1 stop
$1173
Delta Airlines
Sep 07 - Sep 17, Economy
DL
Ontario → London
20h 54m
1:06 PM - 10:00 AM • 1 stop
DL
Ontario → London
26h 55m
6:30 AM - 2:45 PM • 1 stop
$1173
Delta Airlines
Sep 07 - Sep 17, Economy
DL
Ontario → London
25h 20m
12:00 PM - 11:20 AM • 1 stop
DL
Ontario → London
23h 25m
8:40 AM - 2:45 PM • 1 stop
$1173
Delta Airlines
Sep 07 - Sep 17, Economy
DL
Ontario → London
22h 14m
6:01 PM - 3:35 PM • 1 stop
DL
Ontario → London
22h
6:30 AM - 11:50 AM • 1 stop
$1173
Delta Airlines
Aug 29 - Sep 05, Economy
DL
Ontario → London
20h 54m
1:06 PM - 10:00 AM • 1 stop
DL
Ontario → London
23h 25m
8:40 AM - 2:45 PM • 1 stop
$1306
Delta Airlines

Fly from Ontario to London with the Best Airfare Deals on FareLeaders

Looking for a cheap last-minute deal or the best round-trip flight from Ontario to London? Find the biggest savings on one-way and round-trip tickets right here.

FAQs on Ontario to London Flights

What are the airports in Ontario?
ONT
What’s the most popular airline flying from ONT to LHR?
The most popular airline flying from Ontario to London are
Can I fly from ONT to LHR non-stop?
NO
Which airlines fly nonstop between Ontario and London?
The non-stop flights between Ontario and London are .
What’s the earliest departure time from ONT to LHR Airport?
The earliest flight leaves ONT at 7:05 am and lands in LHR - London Heathrow
What are the airports in London?
LHR
Can I make changes to my Ontario to London flight tickets or cancel them on FareLeaders.com?
No. We are an airfare comparison site. All the tickets are booked by the travel agent offering the flight deal and any changes or cancellations to be made are directly done directly by them or the airlines.
Can I cancel my flight tickets from ONT to LHR?
Read the fare rules of the Ontario to London air tickets booked. Some airlines allow you to cancel the tickets within a stipulated time period with a cancellation fee.
Which airline alliances offer flights from Ontario and London?
operate flights between Ontario and London
How long does a flight from Ontario to London take?
It takes approximately 11 hour to fly non-stop from ONT to LHR, which is 5423.46 miles by air.
Which airlines provide the cheapest flights from Ontario (ONT) to London (LHR) ?
In the past couple of days, the cheapest tickets to LHR from ONT were found on DL : USD 1173
Do I need a passport to fly between ONT and LHR?
Yes
What’s the latest departure time from ONT to LHR ?
The last flight leaves ONT at 11:13 pm

Ontario (ONT) to London (LHR): Airport Information

Origin Airport Ontario International , Ontario, US
Destination Airport London Heathrow , London, GB
Distance 5423 miles

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