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$394+ Cheap flights from Ontario (ONT) to Heathrow (LHR)

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 5/1. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — LHR
mar. 26 — abr. 21
mié. 3/26
mié. 4/2
1 adult, Economy
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1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”
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Cheapflights Tip: The best prices from Ontario to London Heathrow are usually found in April or March, booked 49 days in advance, depart on a Wednesday or Sunday and return on a Tuesday

Cheap flight deals from Ontario to Heathrow

Discover tips and strategies to find the most affordable flight options for your journey from Ontario (ONT) to Heathrow (LHR). 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 marzo 21, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$622
(Expedia)

One-way from

$394
(JetBlue)

Popular in

June

Cheapest in

April

Average price

$663
Provider with most accurate pricing for Ontario-London Heathrow flight deals.
Search Deals
Provider most trusted by Cheapflights users for Ontario-London Heathrow flights.
Search Deals
From Ontario to London Heathrow
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One-way flight from Ontario to London Heathrow
Search Deals
Highest demand for flights based on searches. 19% potential increase in price ($188 potential increase over avg. RT price).
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Cheapest flight prices on average. 4% potential price decrease ($33 potential savings vs. average RT price).
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Average for round-trip flights in March 2025
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Find flight deals from Ontario to Heathrow

Cheapest flights from Ontario to Heathrow
Explore the most affordable flight options available from Ontario to Heathrow. Find the lowest fares from popular airlines and budget airlines, with prices last updated on marzo 21, 2025.

This Expedia deal was found by Cheapflights users on 3/19. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 4/810:54 amONT - LHR
1 stop14h 06mIberia
mar. 4/2212:00 pmLHR - ONT
1 stop18h 10mIberia
Deal found 3/19$622
This Cheapflightsfares deal was found by Cheapflights users on 3/20. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 11/45:01 pmONT - LHR
1 stop12h 19mBritish Airways
mar. 11/1810:40 amLHR - ONT
1 stop15h 09mBritish Airways
Deal found 3/20$628
This Trip.com deal was found by Cheapflights users on 3/20. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom. 4/67:00 amONT - LHR
1 stop16h 15mVirgin Atlantic
mar. 4/221:25 pmLHR - ONT
1 stop17h 18mVirgin Atlantic
Deal found 3/20$643
This American Airlines deal was found by Cheapflights users on 3/20. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 8/115:00 pmONT - LHR
1 stop11h 50mAmerican Airlines
mié. 8/2711:15 amLHR - ONT
1 stop14h 33mAmerican Airlines
Deal found 3/20$669
This United Airlines deal was found by Cheapflights users on 3/19. 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.
vie. 5/26:48 pmONT - LHR
2 stops51h 42mUnited Airlines
mié. 5/147:30 amLHR - ONT
2 stops21h 04mUnited Airlines
Deal found 3/19$670
This Mytrip deal was found by Cheapflights users on 3/21. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 4/144:23 pmONT - LHR
2 stops30h 07mAir Canada
mié. 4/309:30 amLHR - ONT
2 stops37h 39mAir Canada
Deal found 3/21$675
This Delta deal was found by Cheapflights users on 3/21. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom. 4/1312:42 pmONT - LHR
1 stop14h 28mDelta
mié. 4/2311:00 amLHR - ONT
1 stop13h 33mDelta
Deal found 3/21$679
This KLM deal was found by Cheapflights users on 3/19. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 5/12:35 pmONT - LHR
1 stop15h 40mKLM
mié. 5/711:00 amLHR - ONT
1 stop20h 42mKLM
Deal found 3/19$693
This United deal was found by Cheapflights users on 3/21. 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 is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 4/236:00 amONT - LHR
2 stops20h 00mMultiple Airlines
dom. 4/272:10 pmLHR - ONT
2 stops40h 45mMultiple Airlines
Deal found 3/21$696
This JetBlue deal was found by Cheapflights users on 3/20. 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 JetBlue is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 5/310:40 pmONT - LHR
1 stop14h 05mJetBlue
mié. 5/148:15 amLHR - ONT
1 stop21h 07mJetBlue
Deal found 3/20$774
This The Travel House deal was found by Cheapflights users on 3/20. 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 The Travel House is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 5/2110:40 pmONT - LHR
1 stop14h 05mIcelandair
mié. 5/288:15 amLHR - ONT
1 stop21h 07mIcelandair
Deal found 3/20$949

Cheapflights Fare Finder

Customize your flight search to find flights from Ontario to Heathrow 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 marzo 21, 2025.
Use the filters below to find and compare flights from Ontario to London Heathrow Airport that are best for you.

Fly from

Ontario

Fly to

Heathrow

Route

Depart

Return

Price

OntarioLondon

ONT - LHR

ONTLHR

Ontario

mar. 4/8

10:54 am-9:00 am

1 stop14h 06m

London Heathrow

mar. 4/22

12:00 pm-10:10 pm

1 stop18h 10m

$622

OntarioLondon

ONT - LHR

ONTLHR

Ontario

dom. 4/6

4:35 pm-12:50 pm

1 stop12h 15m

London Heathrow

mar. 4/22

3:10 pm-10:10 pm

1 stop15h 00m

$639

OntarioLondon

ONT - LHR

ONTLHR

Ontario

dom. 4/6

7:00 am-7:15 am

1 stop16h 15m

London Heathrow

mar. 4/22

1:25 pm-10:43 pm

1 stop17h 18m

$643

OntarioLondon

ONT - LHR

ONTLHR

Ontario

lun. 8/11

5:00 pm-12:50 pm

1 stop11h 50m

London Heathrow

mié. 8/27

11:15 am-5:48 pm

1 stop14h 33m

$669

OntarioLondon

ONT - LHR

ONTLHR

Ontario

vie. 5/2

6:48 pm-6:30 am

2 stops51h 42m

London Heathrow

mié. 5/14

7:30 am-8:34 pm

2 stops21h 04m

$670

OntarioLondon

ONT - LHR

ONTLHR

Ontario

lun. 4/14

4:23 pm-6:30 am

2 stops30h 07m

London Heathrow

mié. 4/30

9:30 am-3:09 pm

2 stops37h 39m

$675

OntarioLondon

ONT - LHR

ONTLHR

Ontario

dom. 4/13

12:42 pm-11:10 am

1 stop14h 28m

London Heathrow

jue. 4/24

10:55 am-4:33 pm

1 stop13h 38m

$679

OntarioLondon

ONT - LHR

ONTLHR

Ontario

jue. 5/1

2:35 pm-2:15 pm

1 stop15h 40m

London Heathrow

mié. 5/7

11:00 am-11:42 pm

1 stop20h 42m

$693

OntarioLondon

ONT - LHR

ONTLHR

Ontario

mié. 4/23

6:00 am-10:00 am

2 stops20h 00m

London Heathrow

dom. 4/27

2:10 pm-10:55 pm

2 stops40h 45m

$696

OntarioLondon

ONT - LHR

ONTLHR

Ontario

sáb. 5/3

10:40 pm-8:45 pm

1 stop14h 05m

London Heathrow

mié. 5/14

8:15 am-9:22 pm

1 stop21h 07m

$774

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/20

Showing 1-10 of 23 results
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2
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Compare providers for flights from Ontario to Heathrow

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 Ontario to Heathrow in March.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
AranGrantPrice Accuracy3 starsTrust Score*1 star
FlightHubPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 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 Ontario-London Heathrow Airport flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Ontario-London Heathrow Airport flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Ontario-London Heathrow Airport flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Ontario-London Heathrow Airport flights, Cheapflights users trust FlightHub the most. FlightHub 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 Ontario-London Heathrow Airport 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 Ontario to Heathrow

Have a flexible travel schedule? Discover the best time to fly to Heathrow from Ontario 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 Ontario to London Heathrow Airport

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

Use this chart to determine the optimal time to book a round-trip flight from Ontario to Heathrow. Price data was last updated on March 14, 2025.

The price you pay for your flight from Ontario to London Heathrow Airport may vary depending on when you book. For the best chance of a lower fare, look to book 49 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

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

Currently, November is the cheapest month in which you can book a flight from Ontario to London Heathrow Airport (average of $661). Flying from Ontario to London Heathrow Airport in June is currently the most expensive (average of $1,122). 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 ONT to LHR?

Find hourly flight availability from Ontario to Heathrow. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated marzo 21, 2025.

It’s typically best to fly out from Ontario to London Heathrow Airport in the morning. Doing so could potentially save you 32% on the flight price compared to flying in the evening, which is usually more expensive.

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

Use this chart to determine the cheapest time to fly round-trip from Ontario to Heathrow. Price data was last updated on December 16, 2024.

Travelers seeking maximum savings on their Ontario to London Heathrow Airport flight should consider departing on Tuesday mornings when fares are most often at their lowest. Thursday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.

Rainfall in Heathrow by month

Plan your trip to Heathrow by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in London Heathrow Airport ranges from 1.6 - 2.8 inches per month. January is typically the wettest month, when rainfall can reach 2.8 in. July is typically the driest time to visit London Heathrow Airport when rainfall is around 1.6 in.

Temperature in Heathrow by month

Plan your trip to Heathrow by taking into account the average temperature totals by month.

If weather is an important factor for your trip to London Heathrow Airport, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 62.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 39.2 F).

Reviews of airlines servicing Heathrow

Get insights into the airlines that provide service to Heathrow. 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 Heathrow. Reviews last updated marzo 21, 2025.
See what other customers who have flown with Delta, KLM and United Airlines from Ontario to London have to say. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
7,895 reviews

Crew

8.5

Comfort

8.0

Boarding

8.2

Food

7.3

Overall

8.0

Entertainment

7.9

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
Delta
8.0
Very good
7,895 reviews
Delta
8.0
Very good
7,895 reviews

Crew

8.5

Comfort

8.0

Boarding

8.2

Food

7.3

Overall

8.0

Entertainment

7.9

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
KLM
7.8
Good
1,319 reviews
Delta
8.0
Very good
7,895 reviews

Crew

8.5

Comfort

8.0

Boarding

8.2

Food

7.3

Overall

8.0

Entertainment

7.9

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
United Airlines
7.4
Good
8,605 reviews
Delta
8.0
Very good
7,895 reviews

Crew

8.5

Comfort

8.0

Boarding

8.2

Food

7.3

Overall

8.0

Entertainment

7.9

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
Virgin Atlantic
7.4
Good
634 reviews
Delta
8.0
Very good
7,895 reviews

Crew

8.5

Comfort

8.0

Boarding

8.2

Food

7.3

Overall

8.0

Entertainment

7.9

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
JetBlue
7.3
Good
2,937 reviews
Delta
8.0
Very good
7,895 reviews

Crew

8.5

Comfort

8.0

Boarding

8.2

Food

7.3

Overall

8.0

Entertainment

7.9

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

Related info for your journey

Find useful and relevant information for your journey from Ontario to Heathrow. 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 from for flights from Ontario to London Heathrow?

    If you book a flight to London Heathrow from Ontario, you will be flying from Ontario, which is the city’s only airport. Ontario (ONT) is located 3.1 mi from the center of Ontario. There are 0 flights from Ontario to London Heathrow per day from 7 different airlines.

  • What are the cheapest airlines flying from Ontario to London Heathrow Airport round-trip?

    According to our current data, Iberia ($622), British Airways ($639), and Virgin Atlantic ($643) offers the cheapest pricing from Ontario to London Heathrow Airport. Iberia is 21% cheaper than the average price of flights available within the next 90 days to this destination.

  • What are the cheapest airlines to fly from Ontario to London Heathrow Airport one-way?

    To fly one-way, consider booking your trip with JetBlue, which is currently one of the cheapest options available, starting at $394. British Airways flights start at $415 while deals on United Airlines start at $423 one-way.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Ontario to Heathrow 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 Ontario to London Heathrow Airport?

    Currently, November is the cheapest month in which you can book a flight from Ontario to London Heathrow Airport (average of $661). Flying from Ontario to London Heathrow Airport in June is currently the most expensive (average of $1,122). 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

Traveling to a place near Ontario?

Book flights to Ontario if you plan to visit one of these locations
Hounslow
Hayes
Thornton Heath
Luton
Wembley
Harrow
Horley
Canterbury
Gatwick
Dover
Orpington
Watford
Milton Keynes
Northampton
Stratford-upon-Avon
Croydon
Borehamwood
Bromley
Folkestone
Ilford

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Top 7 airlines flying from Ontario to Heathrow

Discover the top 7 airlines that operate flights from Ontario to Heathrow. 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 marzo 21, 2025.
AirlineCheapestAverageFlexibilityOn-time
Virgin AtlanticCheapest$454Average$889FlexibilityNo cancel feeOn-time72%
KLMCheapest$481Average$763FlexibilityNo cancel feeOn-time75%
DeltaCheapest$481Average$697FlexibilityNo cancel feeOn-timeN/A
IberiaCheapest$582Average$663FlexibilityNo cancel feeOn-time77%
United AirlinesCheapest$619Average$743FlexibilityNo cancel feeOn-time69%
British AirwaysCheapest$629Average$843FlexibilityNo cancel feeOn-time70%
American AirlinesCheapest$629Average$882FlexibilityNo cancel feeOn-time71%
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