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Ontario

$432+ Cheap flights from Heathrow (LHR) to Ontario (ONT)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 3/4. Fares are subject to change and may not be available on all flights or dates of travel.
LHR — ONT
Feb 20 — Feb 271
Fri 2/20
Fri 2/27
1 adult, Economy
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Cheap flight deals from Heathrow to Ontario

Cheapest flights from Heathrow to Ontario
Explore the most affordable flight options available from Heathrow to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on January 21, 2026.

This United Airlines deal was found by Cheapflights users on 1/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/66:30 am
LHR
-
ONT
2 stops23h 48m
United Airlines
Fri 3/136:15 am
ONT
-
LHR
1 stop18h 10m
United Airlines
Deal found 1/20$465
This United Airlines deal was found by Cheapflights users on 1/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 3/711:30 am
LHR
-
ONT
2 stops19h 27m
United Airlines
Sat 3/141:40 pm
ONT
-
LHR
1 stop34h 45m
United Airlines
Deal found 1/21$466
This United Airlines deal was found by Cheapflights users on 1/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/279:30 am
LHR
-
ONT
2 stops20h 20m
United Airlines
Sat 5/95:00 am
ONT
-
LHR
1 stop23h 20m
United Airlines
Deal found 1/20$481
This United Airlines deal was found by Cheapflights users on 1/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 1/298:30 am
LHR
-
ONT
2 stops21h 28m
United Airlines
Wed 2/115:05 am
ONT
-
LHR
2 stops16h 50m
United Airlines
Deal found 1/20$484
This United Airlines deal was found by Cheapflights users on 1/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 2/218:30 am
LHR
-
ONT
2 stops36h 13m
United Airlines
Sat 3/146:37 pm
ONT
-
LHR
1 stop29h 48m
United Airlines
Deal found 1/20$491
This United Airlines deal was found by Cheapflights users on 1/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 2/910:05 am
LHR
-
ONT
1 stop15h 38m
United Airlines
Mon 2/161:50 pm
ONT
-
LHR
1 stop14h 10m
United Airlines
Deal found 1/19$495
This United Airlines deal was found by Cheapflights users on 1/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/1910:25 am
LHR
-
ONT
1 stop18h 53m
United Airlines
Thu 3/261:50 pm
ONT
-
LHR
1 stop12h 50m
United Airlines
Deal found 1/21$497
This United Airlines deal was found by Cheapflights users on 1/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/201:45 pm
LHR
-
ONT
1 stop16h 12m
United Airlines
Mon 3/231:40 pm
ONT
-
LHR
1 stop15h 20m
United Airlines
Deal found 1/20$504

Find flight deals from Heathrow to Ontario

Discover tips and strategies to find the most affordable flight options for your journey from Heathrow (LHR) to Ontario (ONT). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated January 21, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

Cheapflightsfares
2 stars

Round-trip from

$465
(United Airlines)

One-way from

$432
(United Airlines)

Popular in

December

Cheapest in

January

Average price

$553
Provider with most accurate pricing for London Heathrow-Ontario flight deals.
Search Deals
Provider most trusted by Cheapflights users for London Heathrow-Ontario flights.
Search Deals
From London Heathrow to Ontario
Search Deals
One-way flight from London Heathrow to Ontario
Search Deals
Highest demand for flights based on searches. 8% potential increase in price ($62 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease ($31 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in January 2026
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Heathrow to Ontario that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated January 21, 2026.
Use the filters below to find and compare flights from London Heathrow Airport to Ontario that are best for you.

Fly from

Heathrow

Fly to

Ontario

Route

Depart

Return

Price

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 4/27

9:30 am-9:50 pm

2 stops20h 20m

Ontario

Sat 5/9

6:00 am-12:20 pm

2 stops22h 20m

$482

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 2/21

10:05 am-5:41 pm

1 stop15h 36m

Ontario

Sat 2/28

1:53 pm-12:00 pm

1 stop14h 07m

$496

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Tue 2/10

10:05 am-5:43 pm

1 stop15h 38m

Ontario

Sun 2/15

1:50 pm-12:00 pm

1 stop14h 10m

$496

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 2/7

10:05 am-5:51 pm

1 stop15h 46m

Ontario

Wed 2/11

1:53 pm-12:00 pm

1 stop14h 07m

$496

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Tue 2/10

10:05 am-5:43 pm

1 stop15h 38m

Ontario

Tue 2/17

1:50 pm-12:00 pm

1 stop14h 10m

$497

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 3/4

10:05 am-5:41 pm

1 stop15h 36m

Ontario

Wed 3/25

1:50 pm-9:40 am

1 stop12h 50m

$497

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 3/2

1:45 pm-7:54 pm

1 stop14h 09m

Ontario

Wed 3/11

1:40 pm-12:00 pm

1 stop15h 20m

$497

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 2/21

10:05 am-5:41 pm

1 stop15h 36m

Ontario

Tue 3/17

1:40 pm-12:00 pm

1 stop15h 20m

$497

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Tue 2/3

10:05 am-5:55 pm

1 stop15h 50m

Ontario

Thu 2/12

1:50 pm-12:00 pm

1 stop14h 10m

$497

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 2/18

10:05 am-5:41 pm

1 stop15h 36m

Ontario

Wed 3/11

1:40 pm-12:00 pm

1 stop15h 20m

$497

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/21

Showing 1-10 of 22 results
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2
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Compare providers for flights from Heathrow to Ontario

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Heathrow to Ontario in January.
ProviderPrice AccuracyTrust Score*
FlightHubPrice Accuracy3 starsTrust Score*1 star
Thrive TravelPrice Accuracy3 starsTrust Score*1 star
CheapflightsfaresPrice Accuracy3 starsTrust Score*2 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on London Heathrow Airport-Ontario flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on London Heathrow Airport-Ontario flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from London Heathrow Airport-Ontario flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on London Heathrow Airport-Ontario flights, Cheapflights users trust Cheapflightsfares the most. Cheapflightsfares has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for London Heathrow Airport-Ontario flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from Heathrow to Ontario

Have a flexible travel schedule? Discover the best time to fly to Ontario from Heathrow with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from London Heathrow Airport to Ontario

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

Use this chart to determine the optimal time to book a round-trip flight from Heathrow to Ontario. Price data was last updated on January 16, 2026.

Booking 75 days in advance of your planned departure date is, on average, the best time to get cheap flights from London Heathrow Airport to Ontario. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

What is the cheapest month to book a flight from London Heathrow Airport to Ontario?

Currently, December is the cheapest month in which you can book a flight from London Heathrow Airport to Ontario (average of $444). Flying from London Heathrow Airport to Ontario in July is currently the most expensive (average of $530). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

Reviews of airlines servicing Ontario

Get insights into the airlines that provide service to Ontario. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Ontario. Reviews last updated January 21, 2026.
See what other customers who have flown with United Airlines from London Heathrow Airport to Ontario have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
United Airlines
7.4
Good
9,191 reviews

Boarding

7.7

Overall

7.4

Comfort

7.3

Crew

8.1

Entertainment

7.1

Food

6.6

Reviews

1 / 20
10.0
Excellent

Tim,Sep 2025

LHR - IAD

The premium economy seats were very comfortable and the attention and service by the flight attendants was superb.
United Airlines
7.4
Good
9,191 reviews
United Airlines
7.4
Good
9,191 reviews

Boarding

7.7

Overall

7.4

Comfort

7.3

Crew

8.1

Entertainment

7.1

Food

6.6

Reviews

1 / 20
10.0
Excellent

Tim,Sep 2025

LHR - IAD

The premium economy seats were very comfortable and the attention and service by the flight attendants was superb.

Related info for your journey

Find useful and relevant information for your journey from Heathrow to Ontario. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly into for flights to Ontario from London Heathrow?

    Ontario (ONT) is the airport you will fly into if you book a flight from London Heathrow to Ontario. You should not have trouble finding flights to Ontario from London Heathrow; the airport handles an average of 0 inbound flights from London Heathrow per day. You should also have plenty of airline options to choose from since 1 airline has flights to the Ontario airport from London Heathrow. It is only a 3.1 mi journey from Ontario (ONT) to Ontario’s city center.

  • How long is the flight from London Heathrow Airport to Ontario?

    A quick flight from London Heathrow Airport to Ontario can take about 20h 20m. United Airlines provides one of the quickest options available for as low as $482. The distance from London Heathrow Airport to Ontario is about 5407 mi.

  • What is the cheapest airline to fly from London Heathrow Airport to Ontario round-trip?

    Flying on United Airlines is currently your cheapest option to Ontario, with prices starting at $497. This flight start at 27% lower than the current average price 3 months from now.

  • Can I find deals for flights from Heathrow to Ontario that include hotel bookings?

    Yes. In addition to deals on Heathrow to Ontario flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Heathrow to Ontario?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Heathrow to Ontario.

  • Can I find deals for business class flights from Heathrow to Ontario?

    Yes. Cheapflights offers flight deals from Heathrow to Ontario by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

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

    Currently, December is the cheapest month in which you can book a flight from London Heathrow Airport to Ontario (average of $444). Flying from London Heathrow Airport to Ontario in July is currently the most expensive (average of $530). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

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Alternative routes for Heathrow to Ontario

See prices for flight routes from nearby airports that may be better suited for you.
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Top airline flying from Heathrow to Ontario

Discover the top airline that operate flights from Heathrow to Ontario. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated January 21, 2026.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$497Average$694FlexibilityNo cancel feeOn-time69%

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