LHR - ONT

$438 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 4/29. 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, 0 bags

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
Travelers love KAYAK
41,299,237 searches in the past 7 days on KAYAK

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Everything you should know

Cheapest round-trip
$510
Overall average: $694
United Airlines
Tue 3/10Tue 3/17
LHR - ONT • 2 stops
Cheapest one-way
$438
British Airways
Wed 4/29
LHR - ONT • 2 stops
Top airlines
United Airlines
Cheapest • from $510 (round-trip)
United Airlines
Best reviews • 7.4 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
Nonstop flights
Not available
There are currently no direct flights between Heathrow and Ontario. You'll need at least 1 connection.
Insights
Insights
Insights
Insights
Top layover airports
Dallas (DFW)
Cheapest • Avg $578 (round-trip)
Denver (DEN)
Shortest trip • 14h 08m (one-way)
Insights
Insights
Insights
Insights
When to book
2 weeks
in advance
Our data shows that travelers who book at least 2 weeks in advance save around 48% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
February
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

Tue, Mar 10 - Tue, Mar 17
United Airlines Logo
9:30 am - 8:50 pm
LHR
-
ONT
18h 20m
2 stops
United Airlines Logo
1:50 pm - 9:40 am
ONT
-
LHR
12h 50m
1 stop
$510United Airlines
Tue, Mar 10 - Tue, Mar 17
British Airways Logo
9:55 am - 7:45 pm
LHR
-
ONT
16h 50m
1 stop
British Airways Logo
3:19 pm - 11:40 am
ONT
-
LHR
13h 21m
1 stop
$521British Airways
Mon, Apr 13 - Mon, Apr 20
British Airways Logo
10:05 am - 6:37 pm
LHR
-
ONT
16h 32m
1 stop
British Airways Logo
12:19 pm - 10:50 am
ONT
-
LHR
14h 31m
1 stop
$527British Airways
Tue, Mar 10 - Tue, Mar 17
Air Canada Logo
11:10 am - 10:57 pm
LHR
-
ONT
18h 47m
2 stops
Air Canada Logo
6:15 am - 6:30 am
ONT
-
LHR
17h 15m
2 stops
$528Air Canada
Tue, Apr 14 - Tue, Apr 21
Iberia Logo
6:10 am - 8:54 pm
LHR
-
ONT
22h 44m
2 stops
Iberia Logo
2:08 pm - 2:25 pm
ONT
-
LHR
16h 17m
1 stop
$531Iberia
Tue, Mar 31 - Fri, May 29
Virgin Atlantic Logo
10:55 am - 4:28 pm
LHR
-
ONT
13h 33m
1 stop
Virgin Atlantic Logo
5:50 pm - 3:35 pm
ONT
-
LHR
13h 45m
1 stop
$536Virgin Atlantic
Tue, Apr 14 - Thu, Apr 23
British Airways Logo
10:05 am - 4:22 pm
LHR
-
ONT
14h 17m
1 stop
British Airways Logo
10:59 am - 8:05 am
ONT
-
LHR
13h 06m
1 stop
$537British Airways
Sat, May 2 - Sat, May 9
United Airlines Logo
1:40 pm - 9:58 pm
LHR
-
ONT
16h 18m
1 stop
United Airlines Logo
7:00 am - 6:55 am
ONT
-
LHR
15h 55m
2 stops
$538United Airlines
Thu, Mar 12 - Tue, Mar 24
British Airways Logo
10:15 am - 6:42 pm
LHR
-
ONT
15h 27m
1 stop
British Airways Logo
10:56 am - 6:50 am
ONT
-
LHR
12h 54m
1 stop
$545British Airways
Tue, Apr 14 - Tue, Apr 21
Iberia Logo
8:55 am - 8:54 pm
LHR
-
ONT
19h 59m
1 stop
Iberia Logo
2:08 pm - 12:10 pm
ONT
-
LHR
14h 02m
1 stop
$546Iberia
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 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 February, where tickets cost $534 (return) on average. On the other hand, the most expensive months are December and May, where the average cost of round-trip tickets is $1,019 and $744 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 48% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 11 weeks before departure.

Find deals

Good to know

Low seasonApril
Cheapest flight$438
Best time to beat the crowds with an average 12% drop in price.
Most popular time to fly and prices are also 2% 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 $438 for a one-way ticket and $510 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 9363 reviews
6.6Food
7.7Boarding
8.1Crew
7.3Comfort
7.1Entertainment
Airline reviews

Flight delayed for more than 16 hrs and no effort was spent to provide an alternate

2.0 MediocreHASSAN, Feb 2026
SFO - SNA
Read more United Airlines reviews

Flight delayed for more than 16 hrs and no effort was spent to provide an alternate

Flight attendants were friendly & good service, food sucks, seats uncomfortable, not many Asian movies or shows flying from Hong Kong

Flight attendants had a little attitude. Food tastes no good.

Overall we had a good experience during our flight from San Francisco to Houston.

it was a very short flight so my expectations were low.

Good flight. However, when booked flight with United, assumed the layover included by United in San Francisco of 1 hr and 40 minutes was sufficient . Not so and would recommend at least 2 hours or more. Needed to go through US immigration (very long lineups), then pick up bags, take all the way to another terminal, running because we did not have sufficient time. We made the flight because they held the door for us but luggage didn’t follow.

Very disappointing given gate agent behavior. Filed a formal complaint with United.

Flight delayed. WiFi connectivity very poor if not existant. Last minute arrival forced me to run to catch my connection.

The power at the seat didn't work and the seat itself was difficult to adjust - this was a business class seat. Flight attendant gave me miles to compensate. The attendant was very professional and on top of his game the entire flight.

the whole trip was smooth, and as comfortable as flying is these days. flight crew was friendly and very courteous and helpful.

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

Information on your arrival and departure airports

London Heathrow Airport (LHR)
Ontario (ONT)