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Heathrow

$293+ 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 11/9. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — LHR
oct. 15 — oct. 221
mié. 10/15
mié. 10/22
1 adult, Economy
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Cheapflights Tip: The best prices from Ontario to London Heathrow are usually found in October or March, booked 62 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 septiembre 15, 2025.

Round-trip from

$581
(Iberia)

One-way from

$293
(Kiwi.com)

Popular in

June

Cheapest in

October

Average price

$694
From Ontario to London Heathrow
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One-way flight from Ontario to London Heathrow
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Highest demand for flights based on searches. 22% potential increase in price ($242 potential increase over avg. RT price).
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Cheapest flight prices on average. 5% potential price decrease ($43 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 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 septiembre 15, 2025.

This oojo deal was found by Cheapflights users on 9/14. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 9/234:45 pmONT - LHR
1 stop13h 55mBritish Airways
mar. 10/78:20 amLHR - ONT
1 stop16h 08mBritish Airways
Deal found 9/14$592
This Delta deal was found by Cheapflights users on 9/15. 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.
mié. 9/249:55 amONT - LHR
1 stop15h 55mDelta
mié. 10/16:15 amLHR - ONT
2 stops21h 00mDelta
Deal found 9/15$594
This Delta deal was found by Cheapflights users on 9/15. 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. 11/1611:45 amONT - LHR
1 stop13h 15mDelta
jue. 11/276:30 amLHR - ONT
2 stops19h 48mDelta
Deal found 9/15$595
This Finnair deal was found by Cheapflights users on 9/15. 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 Finnair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 10/272:51 pmONT - LHR
1 stop13h 49mMultiple Airlines
vie. 11/79:55 amLHR - ONT
1 stop17h 46mMultiple Airlines
Deal found 9/15$602
This Virgin Atlantic deal was found by Cheapflights users on 9/14. 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 Virgin Atlantic is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 12/11:20 pmONT - LHR
2 stops15h 30mVirgin Atlantic
mar. 12/911:40 amLHR - ONT
2 stops20h 19mVirgin Atlantic
Deal found 9/14$606
This Delta deal was found by Cheapflights users on 9/14. 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.
sáb. 10/411:55 amONT - LHR
1 stop35h 20mDelta
vie. 10/176:00 pmLHR - ONT
1 stop25h 08mDelta
Deal found 9/14$607
This Trip.com deal was found by Cheapflights users on 9/15. 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.
lun. 9/2212:45 pmONT - LHR
1 stop17h 40mIberia
mar. 10/712:00 pmLHR - ONT
1 stop18h 42mIberia
Deal found 9/15$626
This Trip.com deal was found by Cheapflights users on 9/14. 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.
mié. 10/18:15 amONT - LHR
1 stop16h 45mIberia
mié. 10/812:00 pmLHR - ONT
1 stop18h 42mIberia
Deal found 9/14$627
This oojo deal was found by Cheapflights users on 9/14. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom. 9/2110:55 amONT - LHR
1 stop14h 05mBritish Airways
sáb. 10/48:20 amLHR - ONT
1 stop22h 13mBritish Airways
Deal found 9/14$642
This Iberia deal was found by Cheapflights users on 9/14. 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 Iberia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 9/2312:47 pmONT - LHR
1 stop17h 38mIberia
mar. 10/76:10 amLHR - ONT
2 stops24h 32mIberia
Deal found 9/14$644

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 septiembre 15, 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

mié. 10/29

7:05 am-9:00 am

1 stop18h 55m

London Heathrow

mié. 11/5

6:20 am-10:22 pm

2 stops24h 02m

$594

OntarioLondon

ONT - LHR

ONTLHR

Ontario

dom. 11/16

11:45 am-9:00 am

1 stop13h 15m

London Heathrow

jue. 11/27

6:30 am-6:18 pm

2 stops19h 48m

$595

OntarioLondon

ONT - LHR

ONTLHR

Ontario

lun. 11/17

1:20 pm-10:00 am

1 stop12h 40m

London Heathrow

jue. 11/27

6:30 am-6:18 pm

2 stops19h 48m

$595

OntarioLondon

ONT - LHR

ONTLHR

Ontario

dom. 3/1

11:05 am-8:15 am

1 stop13h 10m

London Heathrow

mar. 3/31

3:10 pm-10:02 pm

1 stop14h 52m

$667

OntarioLondon

ONT - LHR

ONTLHR

Ontario

mar. 12/16

11:50 am-12:50 pm

1 stop17h 00m

London Heathrow

vie. 1/9

8:55 am-9:14 pm

1 stop20h 19m

$672

OntarioLondon

ONT - LHR

ONTLHR

Ontario

sáb. 11/8

11:36 am-9:00 am

1 stop13h 24m

London Heathrow

jue. 11/27

10:45 am-6:04 pm

1 stop15h 19m

$692

OntarioLondon

ONT - LHR

ONTLHR

Ontario

vie. 11/14

6:45 am-10:30 am

1 stop19h 45m

London Heathrow

mar. 11/18

8:55 am-7:37 pm

1 stop18h 42m

$692

OntarioLondon

ONT - LHR

ONTLHR

Ontario

mar. 1/6

7:00 am-5:55 am

1 stop14h 55m

London Heathrow

dom. 1/11

10:05 am-5:43 pm

1 stop15h 38m

$726

OntarioLondon

ONT - LHR

ONTLHR

Ontario

mié. 10/29

1:33 pm-9:40 am

1 stop13h 07m

London Heathrow

dom. 11/2

10:05 am-5:34 pm

1 stop15h 29m

$726

OntarioLondon

ONT - LHR

ONTLHR

Ontario

mié. 11/26

7:00 am-6:30 am

2 stops15h 30m

London Heathrow

mar. 12/2

2:30 pm-10:49 pm

2 stops16h 19m

$737

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/15

Showing 1-10 of 22 results
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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 September 12, 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 62 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 $1,097). 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 septiembre 15, 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.

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 septiembre 15, 2025.
Read through reviews of airlines operating flights from Ontario to London Heathrow Airport, such as Delta, United Airlines, and American Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
7,954 reviews

Food

7.3

Boarding

8.2

Comfort

7.9

Crew

8.5

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
7,954 reviews
Delta
8.0
Very good
7,954 reviews

Food

7.3

Boarding

8.2

Comfort

7.9

Crew

8.5

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
8,929 reviews
Delta
8.0
Very good
7,954 reviews

Food

7.3

Boarding

8.2

Comfort

7.9

Crew

8.5

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.
American Airlines
7.2
Good
10,000 reviews
Delta
8.0
Very good
7,954 reviews

Food

7.3

Boarding

8.2

Comfort

7.9

Crew

8.5

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.
Iberia
7.0
Good
2,924 reviews
Delta
8.0
Very good
7,954 reviews

Food

7.3

Boarding

8.2

Comfort

7.9

Crew

8.5

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.
British Airways
6.7
Okay
7,361 reviews
Delta
8.0
Very good
7,954 reviews

Food

7.3

Boarding

8.2

Comfort

7.9

Crew

8.5

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.

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

    Delta and Iberia can get you from Ontario to London Heathrow Airport in just under 13h 10m. Your travel time can differ by up to 5h 45m. The distance between Ontario and London Heathrow Airport is about 5407 mi. Both multi-stop and nonstop flights can be found to your destination and back.

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

    According to our current data, Virgin Atlantic ($469), Delta ($572), and KLM ($580) offers the cheapest pricing from Ontario to London Heathrow Airport. Virgin Atlantic is 44% cheaper than the average price of flights available within the next 90 days to this destination.

  • 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 $1,097). 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 London Heathrow Airport?

Book flights to London Heathrow Airport if you plan to visit one of these locations
Hounslow
Hayes
Southend-on-Sea
Harrow
Canterbury
Croydon
Eastleigh
Dartford
Dover
Winchester
Orpington
Northampton
Gatwick
Borehamwood
Broadway
Aylesbury
Bedford
Wembley
Folkestone
Chichester

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Alternative routes for Ontario to Heathrow

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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 septiembre 15, 2025.
AirlineCheapestAverageFlexibilityOn-time
Virgin AtlanticCheapest$469Average$884FlexibilityNo cancel feeOn-time72%
DeltaCheapest$572Average$677FlexibilityNo cancel feeOn-timeN/A
KLMCheapest$580Average$653FlexibilityNo cancel feeOn-time75%
IberiaCheapest$582Average$670FlexibilityNo cancel feeOn-time77%
American AirlinesCheapest$653Average$957FlexibilityNo cancel feeOn-time71%
British AirwaysCheapest$662Average$878FlexibilityNo cancel feeOn-time70%
United AirlinesCheapest$677Average$820FlexibilityNo cancel feeOn-time69%

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