LHR - ONT

$416 Find Cheap Flights from London Heathrow Airport to Ontario

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Heathrow to Ontario departing on 2/11. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy

KAYAK searches hundreds of travel sites at once for deals on flights to Ontario

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from London to Ontario, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from London to Ontario, as well as popular online travel agencies
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Everything you should know

Cheapest round-trip
$566
Overall average: $595
Delta
Wed 2/18Tue 2/24
LHR - ONT • 2 stops
Cheapest one-way
$416
British Airways
Wed 2/11
LHR - ONT • 2 stops
Top airlines
Delta
Cheapest • from $566 (round-trip)
United Airlines
Best reviews • 7.4 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
When to book
2 weeks
in advance
Our data shows that travelers who book at least 2 weeks in advance save around 46% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
September
Cheapest • 20% price drop
November
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
Start a new search
KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to Ontario!
Flight Deals
Booking Insights
Flight Deals

Cheap Flights from Heathrow to Ontario (LHR-ONT)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Heathrow to Ontario that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Heathrow to Ontario

Wed, Feb 18 - Tue, Feb 24
Delta Logo
6:30 am - 9:14 pmLHR-ONT
22h 44m2 stops
Delta Logo
1:00 pm - 10:00 amONT-LHR
13h 00m1 stop
$566Delta
Find Deal
Sat, Dec 13 - Tue, Dec 30
Delta Logo
10:45 am - 9:55 pmLHR-ONT
19h 10m1 stop
Delta Logo
1:15 pm - 10:00 amONT-LHR
12h 45m1 stop
$576Delta
Find Deal
Sun, Mar 22 - Thu, Apr 30
Delta Logo
10:45 am - 11:52 pmLHR-ONT
20h 07m1 stop
Delta Logo
11:29 am - 9:00 amONT-LHR
13h 31m1 stop
$582Delta
Find Deal
Thu, Dec 18 - Mon, Dec 29
Virgin Atlantic Logo
2:45 pm - 10:47 pmLHR-ONT
16h 02m1 stop
Virgin Atlantic Logo
11:42 am - 12:50 pmONT-LHR
17h 08m1 stop
$596Virgin Atlantic
Find Deal
Sat, Dec 13 - Thu, Jan 1
Virgin Atlantic Logo
3:05 pm - 10:47 pmLHR-ONT
15h 42m1 stop
Virgin Atlantic Logo
6:38 am - 10:30 amONT-LHR
19h 52m1 stop
$602Virgin Atlantic
Find Deal
Wed, Nov 26 - Wed, Dec 3
United Airlines Logo
8:30 am - 10:31 pmLHR-ONT
22h 01m2 stops
United Airlines Logo
6:00 am - 7:30 amONT-LHR
17h 30m1 stop
$627United Airlines
Find Deal
Wed, Nov 5 - Wed, Nov 12
United Airlines Logo
6:00 pm - 10:31 pmLHR-ONT
36h 31m2 stops
United Airlines Logo
1:33 pm - 9:40 amONT-LHR
12h 07m1 stop
$648United Airlines
Find Deal
Sun, Nov 9 - Sun, Nov 16
British Airways Logo
8:20 am - 6:22 pmLHR-ONT
18h 02m1 stop
British Airways Logo
2:53 pm - 11:40 amONT-LHR
12h 47m1 stop
$649British Airways
Find Deal
Tue, Nov 11 - Tue, Nov 25
British Airways Logo
3:00 pm - 10:29 pmLHR-ONT
15h 29m1 stop
British Airways Logo
2:59 pm - 11:40 amONT-LHR
12h 41m1 stop
$651British Airways
Find Deal
Thu, Dec 25 - Mon, Jan 5
KLM Logo
3:50 pm - 7:50 pmLHR-ONT
36h 00m1 stop
KLM Logo
10:30 pm - 7:50 amONT-LHR
25h 20m1 stop
$661KLM
Find Deal
Booking Insights

KAYAK's insights & trends for Heathrow to Ontario flights

Get data-powered insights and trends into flights from Heathrow to Ontario to help you find the cheapest flights, the best time to fly and much more.

What’s the cheapest day of the week to fly from London Heathrow Airport to Ontario?

The average price of all round-trip flights from London Heathrow Airport to Ontario clicked on KAYAK for each day over the last 12 months.

Your flight ticket price will generally be cheaper if you fly to Ontario on a Tuesday and more expensive on a Monday. On your return trip to London Heathrow Airport, you should consider flying back on a Wednesday, and avoid Saturdays for better deals.

What is the cheapest month to fly from London Heathrow Airport to Ontario?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from London Heathrow Airport to Ontario, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from London Heathrow Airport to Ontario is September, where tickets cost $573 (return) on average. On the other hand, the most expensive months are December and April, where the average cost of round-trip tickets is $939 and $840 respectively.

How far in advance should I book a flight from London Heathrow Airport to Ontario?

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from London Heathrow Airport to Ontario, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from London Heathrow Airport to Ontario, you should book around 2 weeks before departure, which saves you about 46% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 11 weeks before departure.

Good to know

Low seasonFebruary
Cheapest flight$416
Best time to beat the crowds with an average 18% drop in price.
Most popular time to fly and prices are also 9% lower on average.
Flight from London Heathrow Airport to Ontario

When to book flights from Heathrow to Ontario

Are your dates flexible? Find out the best times to travel from Heathrow to Ontario based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking London Heathrow Airport to Ontario flights

  • What is the cheapest flight from London Heathrow Airport to Ontario?

    In the last 3 days, the lowest price for a flight from London Heathrow Airport to Ontario was $416 for a one-way ticket and $566 for a round-trip.

  • Do I need a passport to fly between London Heathrow Airport and Ontario?

    Yes, you'll most likely have to show a valid passport before boarding the plane in London Heathrow Airport and on arrival in Ontario.

  • Which airports will I be using when flying from London Heathrow Airport to Ontario?

    London Heathrow Airport airport is called London Heathrow and the only airport in Ontario is Ontario.

  • Which aircraft models fly most regularly from London Heathrow Airport to Ontario?

    We unfortunately don’t have that data for this specific route.

  • Which airline alliances offer flights from London Heathrow Airport to Ontario?

    Star Alliance is the only airline alliance operating flights between London Heathrow Airport and Ontario.

  • How does KAYAK find such low prices on flights from London Heathrow Airport to Ontario?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from London Heathrow Airport to Ontario.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from London Heathrow Airport to Ontario?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Ontario from London Heathrow Airport is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from London Heathrow Airport to Ontario?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Ontario with an airline and back to London Heathrow Airport with another airline. Booking your flights between London Heathrow Airport and ONT can sometimes prove cheaper using this method.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from London Heathrow Airport to Ontario?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Ontario from London Heathrow Airport up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top airline flying from Heathrow to Ontario

 
See real verified KAYAK customer reviews for airlines flying from London to Ontario. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Heathrow to Ontario? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.4
United AirlinesOverall score based on 8976 reviews
7.3Comfort
6.6Food
7.7Boarding
8.1Crew
7.1Entertainment
Airline reviews

The internet service I paid for didn’t work at all and the flight crew was not very friendly.

6.0 GoodLucia, Oct 2025BNA - SFO
Read more United Airlines reviews

The internet service I paid for didn’t work at all and the flight crew was not very friendly.

Subject: Formal Complaint: Discriminatory and Unprofessional Conduct – Request for Immediate Action & Compensation Dear [Airline Customer Relations Team], I am writing to file a formal complaint regarding my recent travel experience with [Airline], which was by far the worst I have ever encountered. What occurred was not only unprofessional, but in several instances discriminatory, unsafe, and unacceptable. On the first leg of my trip, I arrived only four minutes past check-in. Instead of making any attempt to resolve the matter, your representative flatly denied me boarding and made me wait while she attended to passengers who arrived after me. By the time a manager intervened, it was too late to board, costing me time, money, and unnecessary frustration. The second leg of my trip (Chicago–San Francisco) raised even more serious concerns. From the outset, it was apparent that the staff—particularly two attendants—prioritized Caucasian passengers while dismissing African American and minority passengers. • When a Caucasian passenger in the exit row refused to comply with federal safety requirements, I, as a first responder, immediately offered to switch seats and assume the responsibility. My offer was blatantly ignored, and instead, a Caucasian passenger seated further up was chosen. This was discriminatory and deeply insulting, especially as I was actively de-escalating the situation that could have delayed the flight further. • During a lengthy tarmac delay of over 90 minutes, passengers were given conflicting and unreasonable instructions that created unnecessary distress and tension. • Throughout the flight, a visibly intoxicated passenger directly in front of me was disruptive, rude to others, failed to comply with seatbelt and electronic device rules, and yet faced no enforcement from the crew. In stark contrast, I was singled out for repeated compliance checks even though I was following every rule. This unequal treatment was so obvious that multiple passengers around me spoke up in my defense. This pattern of behavior demonstrated a clear lack of professionalism, disregard for passenger safety, and discriminatory treatment. I expect far better from an airline of your stature. As a paying customer subjected to this unacceptable treatment, I am formally requesting: 1. A full investigation into the conduct of the staff on both flights. 2. A written apology acknowledging the discriminatory and unprofessional behavior I endured. 3. Appropriate compensation for the distress, inconvenience, and mishandling of my travel. If this matter is not addressed promptly and thoroughly, I will have no choice but to escalate my complaint further, including filing with the U.S. Department of Transportation and sharing my experience through other channels. I trust [Airline] will take this complaint seriously and provide a timely resolution.

Check in was quick and easy during early hours. Flight was on time, and customer services was a plus.

I understand that the food on the airplane wouldn’t be fantastic. However, it wasn’t good at all. 😭

The flight was comfortable with the exit row and great service

Plane was crowded and even when we hit altitude, the plane was hot, not enough air flow.

1. when we went to check in, our 2 first class seats had been CANCELED and the flight was sold out. This was done without our prior knowledge. It was all we could do to restore one first class seat for my wife and I flew economy. 2, Our flight home was scheduled to leave at 10:30 pm. Due to tsunami warnings, the roads were closed and our flight status was uncertain as to whether it would leave as scheduled. It was announced that it would now leave at 11:20 pm and the roads were now open since the tsunami had come and gone. We made a mad dash to the airport and checked in. Delays were announced at 12:30 pm, 1:30 am, 2:30 am and at 3:30 am it was canceled. Since this was a flight due to natural (tsunami) causes, there was no compensation. We were told to return at 1:00 pm the next day and our baggage would be kept on the plane since the same plane was going to leave at 1:00 pm. We had to return to our hotel for the rest of the night. The same plane did not leave at 1:00 pm and our baggage was gone! All in all, it was a miserable performance by UA. Information was hard to obtain and no one knew what was going on and what was going to happen. Hundreds of passengers slept on the floor, chairs, etc. No food and no water was made available to the passengers. It was a situation where UA could care less what was going on. As a one million mile flyer, I had not experienced anything like this before and it was hugely disappointing!

I found the staff to not be very attentive at all. When paying for Business Class you expect a certain type of service and that was not found. They were almost rude even

Ok. Get a different kosher caterer. The food was odd.

Our experience on United Airlines was extremely poor. The plane was extremely cold throughout our entire flight- which multiple people complained about- and we had to wait 2 hours to get a blanket which was too thin and barely helped warm us up. As well as this, none of the entertainment features were working so we had to sit through a roughly 10 hour flight with nothing to keep our attention, including the actual flight path screen. It was an extremely disappointing experience and I would hope that this gets fixed if we ever choose United Airlines again.

Everything you need to know for your flight from Heathrow to Ontario

Information on your arrival and departure airports

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