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Ontario

$429+ 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 1/19. Fares are subject to change and may not be available on all flights or dates of travel.
LHR — ONT
Nov 26 — Dec 31
Wed 11/26
Wed 12/3
1 adult, Economy
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Find cheap flights from Heathrow to Ontario with Cheapflights

1. Tell us where you want to go

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Cheapflights Tip: The best prices from London Heathrow to Ontario are usually found in September or February, booked 67 days in advance, depart on a Tuesday or Wednesday and return on a Wednesday

Find 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 October 27, 2025.

This Delta deal was found by Cheapflights users on 10/26. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/256:30 amLHR - ONT
2 stops21h 20mDelta
Tue 12/3011:42 amONT - LHR
1 stop14h 48mDelta
Deal found 10/26$602
This TravelUp deal was found by Cheapflights users on 10/26. 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 TravelUp is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/148:25 pmLHR - ONT
2 stops33h 24mVirgin Atlantic
Thu 12/412:40 pmONT - LHR
1 stop13h 50mVirgin Atlantic
Deal found 10/26$608
This Trip.com deal was found by Cheapflights users on 10/25. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/268:55 amLHR - ONT
1 stop18h 55mDelta
Tue 1/610:30 pmONT - LHR
1 stop25h 20mDelta
Deal found 10/25$610
This Delta deal was found by Cheapflights users on 10/26. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/2511:05 amLHR - ONT
2 stops19h 28mDelta
Sun 12/2811:42 amONT - LHR
1 stop14h 48mDelta
Deal found 10/26$619
This TravelUp deal was found by Cheapflights users on 10/27. 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 TravelUp is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/242:45 pmLHR - ONT
1 stop16h 10mVirgin Atlantic
Mon 12/111:48 amONT - LHR
1 stop17h 02mVirgin Atlantic
Deal found 10/27$622
This TravelUp deal was found by Cheapflights users on 10/26. 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 TravelUp is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/1012:20 pmLHR - ONT
1 stop18h 27mVirgin Atlantic
Wed 12/177:05 amONT - LHR
1 stop16h 45mVirgin Atlantic
Deal found 10/26$623
This lastminute.com deal was found by Cheapflights users on 10/25. 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 lastminute.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/3010:45 amLHR - ONT
1 stop17h 35mVirgin Atlantic
Thu 11/67:05 amONT - LHR
1 stop15h 20mVirgin Atlantic
Deal found 10/25$626
This United Airlines deal was found by Cheapflights users on 10/27. 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.
Wed 11/261:30 pmLHR - ONT
2 stops17h 21mUnited Airlines
Wed 12/31:50 pmONT - LHR
2 stops15h 40mUnited Airlines
Deal found 10/27$628
This lastminute.com deal was found by Cheapflights users on 10/27. 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 lastminute.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/2512:20 pmLHR - ONT
2 stops18h 13mVirgin Atlantic
Tue 12/306:00 amONT - LHR
2 stops17h 05mVirgin Atlantic
Deal found 10/27$632
This TravelUp deal was found by Cheapflights users on 10/26. 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 TravelUp is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/253:00 pmLHR - ONT
1 stop15h 23mBritish Airways
Tue 12/23:19 pmONT - LHR
1 stop12h 56mBritish Airways
Deal found 10/26$634
This Delta deal was found by Cheapflights users on 10/26. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 11/236:30 amLHR - ONT
2 stops24h 34mDelta
Sat 12/67:05 amONT - LHR
2 stops18h 00mDelta
Deal found 10/26$635

Cheap 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 October 27, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$571
(Virgin Atlantic)

One-way from

$429
(United Airlines)

Popular in

December

Cheapest in

September

Average price

$670
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. 4% potential increase in price ($34 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($20 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in October 2025
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 October 27, 2025.
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

Fri 12/26

8:55 am-7:50 pm

1 stop18h 55m

Ontario

Wed 12/31

1:15 pm-10:00 am

1 stop12h 45m

$619

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Tue 1/6

8:55 am-9:07 pm

1 stop20h 12m

Ontario

Fri 4/3

11:55 am-9:00 am

1 stop13h 05m

$627

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Tue 1/6

2:45 pm-10:29 pm

1 stop15h 44m

Ontario

Wed 4/8

11:55 am-9:00 am

1 stop13h 05m

$627

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Fri 1/9

8:55 am-9:07 pm

1 stop20h 12m

Ontario

Mon 4/6

1:00 pm-9:50 am

1 stop12h 50m

$627

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Tue 1/6

2:45 pm-10:29 pm

1 stop15h 44m

Ontario

Thu 4/2

11:55 am-9:00 am

1 stop13h 05m

$627

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 11/26

1:30 pm-10:51 pm

2 stops17h 21m

Ontario

Wed 12/3

1:34 pm-9:40 am

1 stop12h 06m

$628

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sun 11/23

6:30 am-11:04 pm

2 stops24h 34m

Ontario

Sat 12/6

7:05 am-9:05 am

2 stops18h 00m

$635

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 12/10

6:30 am-11:04 pm

2 stops24h 34m

Ontario

Wed 12/17

6:00 am-11:40 am

2 stops21h 40m

$635

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Thu 12/25

6:30 am-5:08 pm

2 stops18h 38m

Ontario

Tue 12/30

7:05 am-6:25 am

1 stop15h 20m

$635

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Fri 11/14

6:30 am-11:04 pm

2 stops24h 34m

Ontario

Thu 12/4

6:00 am-7:50 am

2 stops17h 50m

$636

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/26

Showing 1-10 of 21 results
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2
3

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 October.
ProviderPrice AccuracyTrust Score*
FlightHubPrice Accuracy3 starsTrust Score*1 star
eDreamsPrice Accuracy3 starsTrust Score*3 stars
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 eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on London Heathrow Airport-Ontario flight deals on Cheapflights vs. eDreams >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 eDreams the most. eDreams 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 October 24, 2025.

Booking 66 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 $455). Flying from London Heathrow Airport to Ontario in July is currently the most expensive (average of $556). 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.

What is the cheapest time of day to fly from LHR to ONT?

Find hourly flight availability from Heathrow to Ontario. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated October 27, 2025.

Unlike at noon, when flights are generally more expensive, you can save up to 22% on flights from London Heathrow Airport to Ontario by exploring options for tickets in the afternoon.

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 October 27, 2025.
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
8,997 reviews

Overall

7.4

Comfort

7.3

Crew

8.1

Food

6.6

Entertainment

7.1

Boarding

7.7

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
8,997 reviews
United Airlines
7.4
Good
8,997 reviews

Overall

7.4

Comfort

7.3

Crew

8.1

Food

6.6

Entertainment

7.1

Boarding

7.7

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 18h 55m. Delta provides one of the quickest options available for as low as $619. 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 $560. This flight start at 22% 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 $455). Flying from London Heathrow Airport to Ontario in July is currently the most expensive (average of $556). 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.

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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 October 27, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$560Average$739FlexibilityNo cancel feeOn-time69%

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