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$426+ 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 1/14. Fares are subject to change and may not be available on all flights or dates of travel.
LHR — ONT
Oct 11 — Oct 181
Sat 10/11
Sat 10/18
1 adult, Economy
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Cheapflights Tip: The best prices from London Heathrow to Ontario are usually found in September or February, booked 82 days in advance, depart on a Tuesday or Wednesday and return on a Wednesday

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 September 11, 2025.

Round-trip from

$509
(TravelUp)

One-way from

$426
(Netflights)

Popular in

April

Cheapest in

September

Average price

$576
From London Heathrow to Ontario
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One-way flight from London Heathrow to Ontario
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Highest demand for flights based on searches. 10% potential increase in price ($82 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($12 potential savings vs. average RT price).
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Average for round-trip flights in September 2025
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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 September 11, 2025.

This TravelUp deal was found by Cheapflights users on 9/9. 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 10/77:15 pmLHR - ONT
2 stops35h 26mVirgin Atlantic
Tue 10/147:05 amONT - LHR
1 stop15h 40mVirgin Atlantic
Deal found 9/9$492
This TravelUp deal was found by Cheapflights users on 9/10. 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 11/37:50 pmLHR - ONT
2 stops57h 30mVirgin Atlantic
Mon 11/2411:45 amONT - LHR
1 stop13h 15mVirgin Atlantic
Deal found 9/10$509
This Netflights deal was found by Cheapflights users on 9/10. 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 Netflights is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/278:20 amLHR - ONT
1 stop22h 13mBritish Airways
Mon 10/62:51 pmONT - LHR
1 stop15h 34mBritish Airways
Deal found 9/10$510
This TravelUp deal was found by Cheapflights users on 9/10. 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 11/38:20 amLHR - ONT
1 stop18h 01mBritish Airways
Mon 11/243:19 pmONT - LHR
1 stop12h 56mBritish Airways
Deal found 9/10$512
This British Airways deal was found by Cheapflights users on 9/9. 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 British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/57:35 amLHR - ONT
2 stops22h 54mBritish Airways
Sat 11/224:47 pmONT - LHR
1 stop12h 28mBritish Airways
Deal found 9/9$522
This Netflights deal was found by Cheapflights users on 9/10. 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 Netflights is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/2110:55 amLHR - ONT
1 stop20h 47mVirgin Atlantic
Mon 10/61:15 pmONT - LHR
1 stop12h 35mVirgin Atlantic
Deal found 9/10$529
This British Airways deal was found by Cheapflights users on 9/9. 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 British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/2312:00 pmLHR - ONT
1 stop14h 54mBritish Airways
Tue 9/3010:53 amONT - LHR
1 stop15h 57mBritish Airways
Deal found 9/9$530
This American Airlines deal was found by Cheapflights users on 9/10. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/1911:15 amLHR - ONT
1 stop15h 01mAmerican Airlines
Tue 10/74:49 pmONT - LHR
1 stop13h 51mAmerican Airlines
Deal found 9/10$532
This TravelUp deal was found by Cheapflights users on 9/10. 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 9/171:05 pmLHR - ONT
1 stop17h 18mKLM
Mon 9/221:15 pmONT - LHR
1 stop12h 35mKLM
Deal found 9/10$534
This Delta deal was found by Cheapflights users on 9/10. 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 9/189:55 amLHR - ONT
2 stops20h 28mDelta
Wed 10/16:00 amONT - LHR
1 stop19h 50mDelta
Deal found 9/10$537
This Justfly.com deal was found by Cheapflights users on 9/11. 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 Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/63:10 pmLHR - ONT
1 stop15h 08mBritish Airways
Mon 10/1312:48 pmONT - LHR
1 stop14h 02mBritish Airways
Deal found 9/11$539

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 September 11, 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

Wed 11/5

7:35 am-10:29 pm

2 stops22h 54m

Ontario

Sat 11/22

4:47 pm-1:15 pm

1 stop12h 28m

$522

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 11/5

10:05 am-6:21 pm

1 stop16h 16m

Ontario

Sat 11/22

4:47 pm-1:15 pm

1 stop12h 28m

$530

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Tue 9/23

12:00 pm-6:54 pm

1 stop14h 54m

Ontario

Tue 9/30

10:53 am-10:50 am

1 stop15h 57m

$530

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sun 2/8

10:35 am-5:53 pm

1 stop15h 18m

Ontario

Sat 2/14

11:05 am-8:15 am

1 stop13h 10m

$531

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 2/9

3:00 pm-10:02 pm

1 stop15h 02m

Ontario

Sat 2/14

3:05 pm-12:15 pm

1 stop13h 10m

$531

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Fri 9/26

12:00 pm-6:54 pm

1 stop14h 54m

Ontario

Wed 10/8

2:51 pm-2:25 pm

1 stop15h 34m

$531

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 9/22

12:00 pm-6:54 pm

1 stop14h 54m

Ontario

Mon 9/29

4:45 pm-2:40 pm

1 stop13h 55m

$532

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 9/24

12:00 pm-6:54 pm

1 stop14h 54m

Ontario

Mon 9/29

4:45 pm-2:40 pm

1 stop13h 55m

$532

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 2/14

3:00 pm-11:43 pm

1 stop16h 43m

Ontario

Fri 2/20

11:05 am-10:00 am

1 stop14h 55m

$532

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 2/9

8:40 am-9:14 pm

2 stops20h 34m

Ontario

Sat 2/14

1:00 pm-10:00 am

1 stop13h 00m

$545

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/11

Showing 1-10 of 23 results
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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 August 29, 2025.

Booking 80 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, August is the cheapest month in which you can book a flight from London Heathrow Airport to Ontario (average of $246). Flying from London Heathrow Airport to Ontario in March is currently the most expensive (average of $328). 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 September 11, 2025.

Unlike at noon, when flights are generally more expensive, you can save up to 23% 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 September 11, 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
8,937 reviews

Food

6.6

Boarding

7.7

Overall

7.4

Entertainment

7.1

Crew

8.1

Comfort

7.3

Reviews

1 / 20
10.0
Excellent

Anonymous,Sep 2025

FRA - SFO

Lufthansa was amazing, I wish United States based airlines operated like them.
United Airlines
7.4
Good
8,937 reviews
United Airlines
7.4
Good
8,937 reviews

Food

6.6

Boarding

7.7

Overall

7.4

Entertainment

7.1

Crew

8.1

Comfort

7.3

Reviews

1 / 20
10.0
Excellent

Anonymous,Sep 2025

FRA - SFO

Lufthansa was amazing, I wish United States based airlines operated like them.

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 22h 54m. British Airways provides one of the quickest options available for as low as $522. 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 21% 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, August is the cheapest month in which you can book a flight from London Heathrow Airport to Ontario (average of $246). Flying from London Heathrow Airport to Ontario in March is currently the most expensive (average of $328). 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 September 11, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$560Average$739FlexibilityNo cancel feeOn-time69%

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