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

According to our current data, Lufthansa ($670), United Airlines ($718), and JetBlue ($749) offers the cheapest pricing from Ontario to London Heathrow Airport. Lufthansa is 18% 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 $423 while deals on Air Canada start at $430 one-way.

What are the most popular airlines that fly from Ontario to London Heathrow Airport?

When booking a flight from Ontario to London Heathrow Airport, you may want to consider flying on American Airlines, British Airways or Delta as they are the most popular for this route.

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

Friday flights are generally found to be more expensive for flights from Ontario to London Heathrow Airport. This shouldn’t discourage you from searching, as you can still find great deals by being flexible with your options. Use our search form to find deals on tickets to London Heathrow Airport.

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

Find a great deal and save up to 42% by booking at least 56 days prior to your desired departure date, rather than waiting until the week of travel. According to our data, there are a number of flights available from Ontario to London Heathrow Airport within the next two weeks, with the cheapest ticket starting at $726.

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

Due to multiple factors, expect to potentially pay more when booking in December. For low rates, October can be a great choice for travel to London Heathrow Airport. Flights to London Heathrow Airport from Ontario in October are about $740 on average during October, but can be found for as low as $440.

Most accurate provider : When it comes to deals on Ontario-London Heathrow Airport flights, users find the pricing of AranGrant to be most consistent on Cheapflights vs. AranGrant Users can find the same prices on Ontario-London Heathrow Airport flight deals on Cheapflights vs. AranGrant >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 AranGrant the most. AranGrant 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.

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 6 different airlines.

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.

$394+ Flights from Ontario to London Heathrow Airport

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Find cheap flights from Ontario to Heathrow with Cheapflights

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”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

Cheapflights Tip: The best prices from Ontario to London Heathrow are usually found in March or February, booked 10 days in advance, depart on a Wednesday or Sunday and return on a Tuesday

Cheap flight deals from Ontario to Heathrow

Most accurate provider	AranGrant 3 stars
Most trusted provider	AranGrant 3 stars
Round-trip from	$670 (World Air Fares)
One-way from	$394 (JetBlue)
Popular in	June
Cheapest in	March
Average price	$676

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

Search Deals

One-way flight from Ontario to London Heathrow

Search Deals

Highest demand for flights based on searches. 22% potential increase in price ($235 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 4% potential price decrease ($33 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in April 2025

Search Deals

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 April 29, 2025.

Tue 9/231:15 pmONT - LHR

1 stop12h 25mLufthansa

Fri 10/2411:25 amLHR - ONT

1 stop13h 52mLufthansa

Deal found 4/26

$670

Tue 11/45:01 pmONT - LHR

1 stop12h 19mBritish Airways

Tue 11/182:55 pmLHR - ONT

1 stop15h 05mBritish Airways

Deal found 4/28

$689

Wed 9/241:15 pmONT - LHR

1 stop12h 25mUnited Airlines

Thu 10/24:15 pmLHR - ONT

1 stop14h 37mUnited Airlines

Deal found 4/27

$718

Wed 11/1211:00 amONT - LHR

1 stop13h 15mIberia

Wed 11/262:55 pmLHR - ONT

1 stop15h 05mIberia

Deal found 4/27

$721

Wed 11/57:00 amONT - LHR

2 stops15h 30mMultiple Airlines

Wed 11/121:00 pmLHR - ONT

2 stops17h 35mMultiple Airlines

Deal found 4/28

$724

Tue 9/3011:00 pmONT - LHR

1 stop13h 45mJetBlue

Wed 10/1511:55 amLHR - ONT

1 stop17h 46mJetBlue

Deal found 4/26

$749

Wed 10/15:10 amONT - LHR

2 stops20h 50mAir Canada

Sun 10/192:10 pmLHR - ONT

2 stops35h 22mAir Canada

Deal found 4/26

$751

Wed 8/131:00 pmONT - LHR

1 stop12h 50mKLM

Sat 8/306:30 amLHR - ONT

2 stops18h 58mKLM

Deal found 4/28

$754

Wed 9/107:00 amONT - LHR

2 stops19h 15mDelta

Sat 9/206:30 amLHR - ONT

2 stops21h 12mDelta

Deal found 4/28

$758

Sun 5/410:40 pmONT - LHR

1 stop14h 05mIcelandair

Sun 5/118:15 amLHR - ONT

1 stop20h 56mIcelandair

Deal found 4/27

$846

Mon 4/284:35 pmONT - LHR

1 stop12h 15mAmerican Airlines

Tue 5/133:40 pmLHR - ONT

1 stop14h 17mAmerican Airlines

Deal found 4/27

$978

Best flights from Ontario to Heathrow
Discover carefully curated flight deals from Ontario to Heathrow that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated April 29, 2025.

Tue 9/231:15 pmONT - LHR

1 stop12h 25mLufthansa

Fri 10/2411:25 amLHR - ONT

1 stop13h 52mLufthansa

Deal found 4/26

$670

Wed 9/241:15 pmONT - LHR

1 stop12h 25mUnited Airlines

Thu 10/24:15 pmLHR - ONT

1 stop14h 37mUnited Airlines

Deal found 4/27

$718

Tue 9/3011:00 pmONT - LHR

1 stop13h 45mJetBlue

Wed 10/1511:55 amLHR - ONT

1 stop17h 46mJetBlue

Deal found 4/26

$749

Wed 10/15:10 amONT - LHR

2 stops20h 50mAir Canada

Sat 10/182:10 pmLHR - ONT

2 stops30h 03mAir Canada

Deal found 4/26

$751

Wed 8/131:00 pmONT - LHR

1 stop12h 50mKLM

Sat 8/306:30 amLHR - ONT

2 stops18h 58mKLM

Deal found 4/28

$754

Wed 9/107:00 amONT - LHR

2 stops19h 15mDelta

Sat 9/206:30 amLHR - ONT

2 stops21h 12mDelta

Deal found 4/28

$758

Wed 8/276:00 amONT - LHR

2 stops16h 35mMultiple Airlines

Sun 9/79:30 amLHR - ONT

2 stops19h 03mMultiple Airlines

Deal found 4/27

$774

Wed 8/2712:46 pmONT - LHR

1 stop17h 39mIberia

Mon 9/810:50 amLHR - ONT

2 stops20h 46mIberia

Deal found 4/27

$782

Mon 8/44:45 pmONT - LHR

1 stop12h 05mBritish Airways

Thu 8/143:40 pmLHR - ONT

1 stop13h 59mBritish Airways

Deal found 4/28

$802

Tue 9/2311:00 pmONT - LHR

1 stop13h 45mIcelandair

Fri 10/248:25 amLHR - ONT

2 stops21h 16mIcelandair

Deal found 4/26

$846

Fri 5/94:35 pmONT - LHR

1 stop12h 15mAmerican Airlines

Thu 5/223:40 pmLHR - ONT

1 stop14h 17mAmerican Airlines

Deal found 4/28

$1,028

Last-minute flights from Ontario to Heathrow
Discover last-minute flight deals from Ontario to Heathrow. Data last updated April 29, 2025 and is based on user searches.

Mon 4/284:35 pmONT - LHR

1 stop12h 15mAmerican Airlines

Tue 5/133:40 pmLHR - ONT

1 stop14h 17mAmerican Airlines

Deal found 4/27

$978

Tue 4/2911:45 amONT - LHR

1 stop15h 35mDelta

Sat 5/176:30 amLHR - ONT

2 stops24h 38mDelta

Deal found 4/28

$1,024

Tue 4/296:00 amONT - LHR

2 stops16h 30mUnited Airlines

Sat 5/179:30 amLHR - ONT

2 stops20h 30mUnited Airlines

Deal found 4/28

$1,025

Tue 4/2912:07 pmONT - LHR

1 stop15h 03mKLM

Tue 6/310:55 amLHR - ONT

1 stop13h 22mKLM

Deal found 4/27

$1,280

Sun 5/410:40 pmONT - LHR

1 stop14h 05mIcelandair

Sun 5/118:15 amLHR - ONT

1 stop20h 56mIcelandair

Deal found 4/27

$846

Sun 5/44:35 pmONT - LHR

1 stop12h 15mBritish Airways

Sun 5/113:40 pmLHR - ONT

1 stop14h 17mBritish Airways

Deal found 4/27

$1,038

Sun 5/412:10 amONT - LHR

1 stop32h 20mChina Airlines

Fri 5/239:10 pmLHR - ONT

1 stop28h 50mChina Airlines

Deal found 4/27

$9,941

Mon 5/510:40 pmONT - LHR

1 stop14h 05mJetBlue

Wed 5/218:15 amLHR - ONT

1 stop20h 56mJetBlue

Deal found 4/28

$794

Mon 5/54:15 pmONT - LHR

2 stops33h 45mAir Canada

Fri 5/239:30 amLHR - ONT

2 stops35h 01mAir Canada

Deal found 4/27

$1,041

Mon 5/54:35 pmONT - LHR

1 stop12h 15mMultiple Airlines

Mon 5/1910:05 pmLHR - ONT

2 stops31h 50mMultiple Airlines

Deal found 4/28

$1,471

Tue 5/64:15 pmONT - LHR

1 stop12h 05mUnited Airlines

Tue 5/131:40 pmLHR - ONT

1 stop16h 20mUnited Airlines

Deal found 4/26

$988

Tue 5/611:25 pmONT - LHR

2 stops32h 10mAvianca

Mon 5/1210:05 pmLHR - ONT

2 stops31h 50mAvianca

Deal found 4/26

$1,739

One-way flights from Ontario to Heathrow
Search for one-way flight options from Ontario to Heathrow. Find affordable one-way fares based on user searches. Data last updated April 29, 2025.

Thu 9/1811:00 pmONT - LHR

1 stop13h 45mJetBlue

Deal found 4/27

$394

Sun 7/274:45 pmONT - LHR

1 stop12h 05mBritish Airways

Deal found 4/28

$423

Mon 8/115:05 amONT - LHR

2 stops17h 30mAir Canada

Deal found 4/28

$430

Sat 8/26:39 pmONT - LHR

1 stop31h 46mUnited Airlines

Deal found 4/28

$435

Thu 7/317:05 amONT - LHR

1 stop15h 40mDelta

Deal found 4/27

$473

Wed 7/99:44 amONT - LHR

1 stop16h 06mVirgin Atlantic

Deal found 4/26

$515

Mon 5/121:10 pmONT - LHR

1 stop12h 40mKLM

Deal found 4/28

$519

Wed 5/216:47 pmONT - LHR

3 stops43h 18mMultiple Airlines

Deal found 4/27

$599

Mon 5/52:44 pmONT - LHR

2 stops18h 31mIberia

Deal found 4/28

$685

Tue 6/311:25 pmONT - LHR

2 stops32h 10mAvianca

Deal found 4/28

$736

Tue 6/171:33 pmONT - LHR

1 stop12h 07mLufthansa

Deal found 4/27

$758

Sun 9/287:00 amONT - LHR

2 stops45h 05mWestJet

Deal found 4/28

$2,334

Cheapflights Fare Finder

Use the filters below to find and compare flights from Ontario to London Heathrow Airport that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Tue 9/23

1:15 pm-9:40 am

1 stop12h 25m

London Heathrow

Fri 10/24

11:25 am-5:17 pm

1 stop13h 52m

$670

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 9/24

1:15 pm-9:40 am

1 stop12h 25m

London Heathrow

Thu 10/2

4:15 pm-10:52 pm

1 stop14h 37m

$718

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Tue 9/30

11:00 pm-8:45 pm

1 stop13h 45m

London Heathrow

Wed 10/15

11:55 am-9:41 pm

1 stop17h 46m

$749

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 10/1

5:10 am-10:00 am

2 stops20h 50m

London Heathrow

Sun 10/19

2:10 pm-5:32 pm

2 stops35h 22m

$751

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 8/13

1:00 pm-9:50 am

1 stop12h 50m

London Heathrow

Sat 8/30

6:30 am-5:28 pm

2 stops18h 58m

$754

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 9/10

7:00 am-10:15 am

2 stops19h 15m

London Heathrow

Sat 9/20

6:30 am-7:42 pm

2 stops21h 12m

$758

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 8/27

6:00 am-6:35 am

2 stops16h 35m

London Heathrow

Sun 9/7

9:30 am-8:33 pm

2 stops19h 03m

$774

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 8/27

12:46 pm-2:25 pm

1 stop17h 39m

London Heathrow

Mon 9/8

10:50 am-11:36 pm

2 stops20h 46m

$782

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Mon 8/4

4:45 pm-12:50 pm

1 stop12h 05m

London Heathrow

Thu 8/14

3:40 pm-9:39 pm

1 stop13h 59m

$802

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Tue 9/23

11:00 pm-8:45 pm

1 stop13h 45m

London Heathrow

Fri 10/24

8:25 am-9:41 pm

2 stops21h 16m

$846

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/27

Showing 1-10 of 24 results

Compare providers for flights from Ontario to Heathrow

Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Ontario to Heathrow in April.

Provider	Price Accuracy	Trust Score*
Expedia	Price Accuracy1 star	Trust Score*3 stars
AranGrant	Price Accuracy3 stars	Trust Score*3 stars
FlightHub	Price Accuracy3 stars	Trust Score*2 stars
eDreams	Price Accuracy3 stars	Trust 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 AranGrant to be most consistent on Cheapflights vs. AranGrant Users can find the same prices on Ontario-London Heathrow Airport flight deals on Cheapflights vs. AranGrant >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 AranGrant the most. AranGrant 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?

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 10 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 $1,110). 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?

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?

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

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

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

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

7,929 reviews

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

7,929 reviews

Delta

8.0

Very good

7,929 reviews

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

1,333 reviews

Delta

8.0

Very good

7,929 reviews

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

8,696 reviews

Delta

8.0

Very good

7,929 reviews

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

642 reviews

Delta

8.0

Very good

7,929 reviews

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

2,922 reviews

Delta

8.0

Very good

7,929 reviews

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

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 6 different airlines.
What are the cheapest airlines flying from Ontario to London Heathrow Airport round-trip?
According to our current data, Lufthansa ($670), United Airlines ($718), and JetBlue ($749) offers the cheapest pricing from Ontario to London Heathrow Airport. Lufthansa is 18% 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 $423 while deals on Air Canada start at $430 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 $1,110). 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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Top 6 airlines flying from Ontario to Heathrow

Airline	Cheapest	Average	Flexibility	On-time
Virgin Atlantic	Cheapest$454	Average$884	FlexibilityNo cancel fee	On-time72%
Iberia	Cheapest$582	Average$663	FlexibilityNo cancel fee	On-time77%
Delta	Cheapest$598	Average$777	FlexibilityNo cancel fee	On-timeN/A
British Airways	Cheapest$629	Average$838	FlexibilityNo cancel fee	On-time70%
United Airlines	Cheapest$629	Average$768	FlexibilityNo cancel fee	On-time69%
American Airlines	Cheapest$629	Average$892	FlexibilityNo cancel fee	On-time71%

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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 9/18. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from Ontario to Heathrow with Cheapflights

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2. Select your favorite providers

3. Compare prices and book

Cheapflights Tip: The best prices from Ontario to London Heathrow are usually found in March or February, booked 10 days in advance, depart on a Wednesday or Sunday and return on a Tuesday

Cheap flight deals from Ontario to Heathrow

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Find flight deals from Ontario to Heathrow

Cheapest flights from Ontario to HeathrowExplore 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 April 29, 2025.

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 April 29, 2025.

Cheapflights Fare Finder

Use the filters below to find and compare flights from Ontario to London Heathrow Airport that are best for you.

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 April.

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.

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 April 25, 2025.

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

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 April 29, 2025.

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.

Rainfall in Heathrow by month

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

Temperature in Heathrow by month

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

Reviews of airlines servicing Heathrow

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.

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?

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

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

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

How can I find direct flights from Ontario to Heathrow?

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

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

Traveling to a place near Ontario?

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Alternative routes for Ontario to Heathrow

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Top 6 airlines flying from Ontario to Heathrow

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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 April 29, 2025.