Cheap Flight Tickets from Ontario (ONT) to London (LHR), Starting at $1303

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

$1303

DL Delta Airlines • 1 stop • 22h 14m

Aug 07 – Aug 17

The cheapest round trip flight from Ontario to London (ONT-LHR-ONT) is currently $1303

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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

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 07 - Aug 17, Economy
DL
Ontario → London
22h 14m
6:01 PM - 3:35 PM • 1 stop
DL
Ontario → London
26h 55m
6:30 AM - 2:45 PM • 1 stop
$1303
Delta Airlines
Aug 07 - Aug 17, Economy
DL
Ontario → London
25h 20m
12:00 PM - 11:20 AM • 1 stop
DL
Ontario → London
26h 55m
6:30 AM - 2:45 PM • 1 stop
$1303
Delta Airlines
Aug 07 - Aug 17, Economy
DL
Ontario → London
20h 54m
1:06 PM - 10:00 AM • 1 stop
DL
Ontario → London
22h
6:30 AM - 11:50 AM • 1 stop
$1303
Delta Airlines
Aug 07 - Aug 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
$1303
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 1303
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 6:01 pm

Essential Information for Booking Flights from Ontario (ONT) - AI Insights

What's the cheapest airline from ont to lhr?
You can find affordable flights from Ontario to London Heathrow on Alaska Airlines. For a round-trip Business class ticket, book at least 17 days in advance to get the best Low Fares. Budget-friendly options are available during July and November when airfares tend to be lower.
What's the popular airline to fly from ont to lhr?
You can fly from Ontario International Airport (ONT) to London Heathrow Airport (LHR) on Alaska Airlines. As a business class passenger, you'll enjoy priority check-in, lounge access, and flatbed seats. Booking in advance is recommended, as it's best to book at least 17 days prior to your trip for the best fares.
What's the cheapest day of the week to fly from ont to lhr?
The cheapest day to fly from Ontario International Airport (ONT) to London Heathrow Airport (LHR) is Sunday. Flying on Sundays can result in lower fares compared to other days of the week, making it a budget-friendly option for your round-trip Business class flight.
What's the cheapest month to fly from ont to lhr?
The cheapest month to fly from Ontario (ONT) to London Heathrow (LHR) is November. Flying during this time can result in low fares, making it a budget-friendly option for your round-trip business class flight.
Which airline/airlines fly from ont to lhr?
Flights from Ontario International to London Heathrow are available on United Airlines, JetBlue Airways, Alaska Airlines, Delta Airlines, and American Airlines. You can find budget-friendly flights with these airlines.
What is the cheapest airline to fly from Ontario International Airport to London Heathrow?
Alaska Airlines (AS)
How far in advance should I book my airfare for a round trip ticket?
It is recommended to book your airfare at least 17 days in advance for the cheapest fares.
Can I find cheap flights on fareleaders.com for my next weekend getaway?
Yes, you can search for cheap flights on fareleaders.com and get exclusive deals on your desired route.
What are some airlines that offer business class flights with priority and lounge access?
Alaska Airlines (AS), United Airlines (UA), JetBlue Airways (B6), Delta Airlines (DL), American Airlines (AA) offer business class flights with priority and lounge access.
How do I book my airfare online through fareleaders.com?
You can book your airfare online through fareleaders.com by following the booking process on our website.
Are there any discounts or promotions available for advance bookings on this route?
Yes, there are discounts and promotions available for advance bookings on this route. Check our website for exclusive offers.

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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