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

Cheapflights users have booked flights from Ontario to London Heathrow Airport round-trip from £506. Other airlines that can offer you cheap pricing are Air Canada, from £518, and United Airlines, from £526. Delta is currently priced 17% below the average price you’ll pay for this route.

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

For one-way options, check prices for Delta. According to our data, you can fly for as low as £286. Users have also found prices from £294 and £295 on JetBlue and Virgin Atlantic, respectively.

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

To save up to 42% on this flight, we recommend booking at least 56 days prior to travel. The price may fluctuate and will likely increase closer to your departure date. Users on Cheapflights have found tickets from Ontario to London Heathrow Airport from £541 1-2 weeks out and tickets from £729 for flights departing within the next 72 hours.

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

October can be a great time to fly to London Heathrow Airport from Ontario with a flight ticket averaging about £552. Cheapflights users have found deals in the month of October for as cheap as £328. The most expensive prices can be found in the month of December.

What airport do you fly from for flights from Ontario to London Heathrow?

Most people fly from Ontario (ONT) if they book a flight from Ontario to London Heathrow. On average, Ontario has 0 outbound flights to London Heathrow per day from 0 airlines. Ontario is conveniently located just 3.1 mi from Ontario’s city center.

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 holiday 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.

£286+ Flights from Ontario to London Heathrow Airport - Compare & Save Big

Cheap flight deals from Ontario to Heathrow

Round-trip from	£506
One-way from	£286
Popular in	June
Cheapest in	March
Average price	£504

Delta
13/8-30/8
3 total stops
44h 29m total
Ontario to London

Search Deals

Delta
13/5
1 total stop
15h 36m total
Ontario to London

Search Deals

Highest demand for flights based on searches. 22% potential increase in price (£130 potential increase over avg. return price).

Search Deals

Cheapest flight prices on average. 4% potential price decrease (£19 potential savings vs. average return 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 30 April 2025.

Wed 13/807:00ONT - LHR

1 stop23h 15mDelta

Sat 30/806:15LHR - ONT

2 stops21h 14mDelta

Deal found 29/4£506

Tue 4/1117:01ONT - LHR

1 stop12h 19mBritish Airways

Tue 18/1114:55LHR - ONT

1 stop15h 05mBritish Airways

Deal found 28/4£514

Wed 10/905:10ONT - LHR

2 stops17h 20mAir Canada

Fri 19/914:05LHR - ONT

2 stops30h 27mAir Canada

Deal found 29/4£518

Tue 13/516:15ONT - LHR

1 stop12h 05mUnited Airlines

Tue 20/509:30LHR - ONT

2 stops19h 04mUnited Airlines

Deal found 29/4£526

Wed 12/1111:00ONT - LHR

1 stop13h 15mIberia

Wed 26/1114:55LHR - ONT

1 stop15h 05mIberia

Deal found 27/4£538

Wed 5/1107:00ONT - LHR

2 stops15h 30mMultiple Airlines

Wed 12/1113:00LHR - ONT

2 stops17h 35mMultiple Airlines

Deal found 29/4£540

Sun 21/923:00ONT - LHR

1 stop13h 45mJetBlue

Tue 21/1011:55LHR - ONT

1 stop17h 46mJetBlue

Deal found 29/4£559

Wed 13/813:00ONT - LHR

1 stop12h 50mKLM

Sat 30/806:30LHR - ONT

2 stops18h 58mKLM

Deal found 28/4£562

Tue 6/522:59ONT - LHR

1 stop13h 46mIcelandair

Tue 13/508:15LHR - ONT

1 stop20h 56mIcelandair

Deal found 29/4£587

Mon 28/416:35ONT - LHR

1 stop12h 15mAmerican Airlines

Tue 13/515:40LHR - ONT

1 stop14h 17mAmerican Airlines

Deal found 28/4£731

Best flights from Ontario to Heathrow
Discover carefully curated flight deals from Ontario to Heathrow that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 30 April 2025.

Wed 13/807:00ONT - LHR

1 stop23h 15mDelta

Sat 30/806:15LHR - ONT

2 stops21h 14mDelta

Deal found 29/4£506

Wed 10/905:10ONT - LHR

2 stops17h 20mAir Canada

Fri 19/914:05LHR - ONT

2 stops30h 27mAir Canada

Deal found 29/4£518

Tue 13/516:15ONT - LHR

1 stop12h 05mUnited Airlines

Tue 20/509:30LHR - ONT

2 stops19h 04mUnited Airlines

Deal found 29/4£526

Sun 21/923:00ONT - LHR

1 stop13h 45mJetBlue

Tue 21/1011:55LHR - ONT

1 stop17h 46mJetBlue

Deal found 29/4£559

Mon 12/507:30ONT - LHR

1 stop21h 15mBritish Airways

Mon 19/506:15LHR - ONT

2 stops20h 21mBritish Airways

Deal found 28/4£559

Wed 13/813:00ONT - LHR

1 stop12h 50mKLM

Sat 30/806:30LHR - ONT

2 stops18h 58mKLM

Deal found 28/4£562

Wed 27/805:10ONT - LHR

2 stops17h 25mMultiple Airlines

Mon 8/908:30LHR - ONT

2 stops20h 03mMultiple Airlines

Deal found 28/4£582

Mon 11/810:51ONT - LHR

1 stop15h 59mIberia

Mon 18/809:15LHR - ONT

2 stops22h 14mIberia

Deal found 27/4£635

Fri 9/522:59ONT - LHR

1 stop13h 46mIcelandair

Sun 18/511:55LHR - ONT

1 stop17h 16mIcelandair

Deal found 29/4£690

Fri 9/516:35ONT - LHR

1 stop12h 15mAmerican Airlines

Thu 22/515:40LHR - ONT

1 stop14h 17mAmerican Airlines

Deal found 28/4£767

Sat 7/607:05ONT - LHR

1 stop16h 10mVirgin Atlantic

Fri 20/606:30LHR - ONT

2 stops24h 16mVirgin Atlantic

Deal found 28/4£867

Last-minute flights from Ontario to Heathrow
Discover last-minute flight deals from Ontario to Heathrow. Data last updated 30 April 2025 and is based on user searches.

Tue 29/413:20ONT - LHR

1 stop12h 30mDelta

Sat 17/506:30LHR - ONT

2 stops24h 05mDelta

Deal found 29/4£764

Tue 29/413:35ONT - LHR

2 stops33h 00mMultiple Airlines

Sat 17/515:50LHR - ONT

2 stops28h 48mMultiple Airlines

Deal found 29/4£767

Tue 29/416:35ONT - LHR

1 stop12h 15mAmerican Airlines

Sun 4/515:40LHR - ONT

1 stop14h 18mAmerican Airlines

Deal found 28/4£859

Fri 2/507:00ONT - LHR

1 stop15h 25mIberia

Tue 20/511:30LHR - ONT

2 stops20h 13mIberia

Deal found 29/4£729

Sun 4/500:10ONT - LHR

1 stop32h 20mChina Airlines

Fri 23/521:10LHR - ONT

1 stop28h 50mChina Airlines

Deal found 27/4£7,413

Mon 5/506:00ONT - LHR

1 stop17h 25mUnited Airlines

Fri 23/509:30LHR - ONT

2 stops19h 34mUnited Airlines

Deal found 27/4£773

Mon 5/516:15ONT - LHR

2 stops33h 45mAir Canada

Fri 23/509:30LHR - ONT

2 stops35h 01mAir Canada

Deal found 27/4£776

Tue 6/522:59ONT - LHR

1 stop13h 46mIcelandair

Tue 13/508:15LHR - ONT

1 stop20h 56mIcelandair

Deal found 29/4£587

Wed 7/522:59ONT - LHR

1 stop13h 46mJetBlue

Wed 21/508:15LHR - ONT

1 stop20h 56mJetBlue

Deal found 29/4£592

Wed 7/513:10ONT - LHR

1 stop12h 40mMultiple Airlines

Sun 11/510:55LHR - ONT

1 stop13h 22mMultiple Airlines

Deal found 29/4£1,044

Wed 7/506:00ONT - LHR

2 stops22h 05mWestJet

Fri 9/514:10LHR - ONT

2 stops16h 25mWestJet

Deal found 28/4£8,159

Thu 8/516:35ONT - LHR

1 stop12h 15mBritish Airways

Thu 15/515:40LHR - ONT

1 stop14h 17mBritish Airways

Deal found 28/4£774

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 30 April 2025.

Tue 13/511:44ONT - LHR

1 stop15h 36mDelta

Deal found 29/4£286

Wed 1/1023:00ONT - LHR

1 stop13h 45mJetBlue

Deal found 29/4£294

Sun 24/807:00ONT - LHR

1 stop15h 45mVirgin Atlantic

Deal found 28/4£295

Tue 19/810:51ONT - LHR

1 stop14h 09mIberia

Deal found 29/4£301

Mon 21/716:45ONT - LHR

1 stop12h 05mBritish Airways

Deal found 28/4£304

Tue 13/505:05ONT - LHR

2 stops21h 35mUnited Airlines

Deal found 29/4£315

Sat 16/813:00ONT - LHR

1 stop12h 50mKLM

Deal found 29/4£350

Sun 4/506:00ONT - LHR

2 stops23h 20mAir Canada

Deal found 28/4£412

Wed 21/518:47ONT - LHR

3 stops43h 18mMultiple Airlines

Deal found 27/4£447

Tue 3/623:25ONT - LHR

2 stops32h 10mAvianca

Deal found 29/4£549

Thu 12/616:50ONT - LHR

1 stop12h 00mAmerican Airlines

Deal found 29/4£705

Wed 27/807:00ONT - LHR

2 stops21h 05mWestJet

Deal found 29/4£1,738

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

Wed 13/8

07:00-14:15

1 stop23h 15m

London Heathrow

Sat 30/8

06:15-19:29

2 stops21h 14m

£506

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 10/9

05:10-06:30

2 stops17h 20m

London Heathrow

Fri 19/9

14:05-12:32

2 stops30h 27m

£518

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Tue 13/5

16:15-12:20

1 stop12h 05m

London Heathrow

Tue 20/5

09:30-20:34

2 stops19h 04m

£526

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Sun 21/9

23:00-20:45

1 stop13h 45m

London Heathrow

Tue 21/10

11:55-21:41

1 stop17h 46m

£559

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Mon 12/5

07:30-12:45

1 stop21h 15m

London Heathrow

Mon 19/5

06:15-18:36

2 stops20h 21m

£559

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 13/8

13:00-09:50

1 stop12h 50m

London Heathrow

Sat 30/8

06:30-17:28

2 stops18h 58m

£562

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 27/8

05:10-06:35

2 stops17h 25m

London Heathrow

Mon 8/9

08:30-20:33

2 stops20h 03m

£582

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Mon 11/8

10:51-10:50

1 stop15h 59m

London Heathrow

Mon 18/8

09:15-23:29

2 stops22h 14m

£635

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Fri 9/5

22:59-20:45

1 stop13h 46m

London Heathrow

Sun 18/5

11:55-21:11

1 stop17h 16m

£690

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Fri 9/5

16:35-12:50

1 stop12h 15m

London Heathrow

Thu 22/5

15:40-21:57

1 stop14h 17m

£767

Flights are sorted by cheapest return flights first.

Deals found on 29/4

Showing 1-10 of 23 results

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 return 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?

To ensure you get the cheapest price possible for a flight from Ontario to London Heathrow Airport, you should look to book at least 10 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.

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

Currently, January is the cheapest month in which you can book a flight from Ontario to London Heathrow Airport (average of £112). Flying from Ontario to London Heathrow Airport in August is currently the most expensive (average of £164). 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?

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Ontario to London Heathrow Airport as you normally would.

Rainfall in Heathrow by month

In terms of precipitation, rainfall in London Heathrow Airport ranges from 40.0 - 70.0 inches per month. January is typically the wettest month, when rainfall can reach 70.0 mm. July is typically the driest time to visit London Heathrow Airport when rainfall is around 40.0 mm.

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 17.0 C. Travellers hoping to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 4.0 C).

Reviews of airlines servicing Heathrow

Read reviews from past customers who have flown Delta, KLM and United Airlines from Ontario to London. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.

Delta

8.0

Very Good

7,936 reviews

Check prices

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

7,936 reviews

Delta

8.0

Very Good

7,936 reviews

Check prices

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

7,936 reviews

Check prices

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

7,936 reviews

Check prices

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

7,936 reviews

Check prices

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

7,936 reviews

Check prices

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?
Most people fly from Ontario (ONT) if they book a flight from Ontario to London Heathrow. On average, Ontario has 0 outbound flights to London Heathrow per day from 0 airlines. Ontario is conveniently located just 3.1 mi from Ontario’s city center.
What are the cheapest airlines flying from Ontario to London Heathrow Airport round-trip?
Cheapflights users have booked flights from Ontario to London Heathrow Airport round-trip from £506. Other airlines that can offer you cheap pricing are Air Canada, from £518, and United Airlines, from £526. Delta is currently priced 17% below the average price you’ll pay for this route.
What are the cheapest airlines to fly from Ontario to London Heathrow Airport one-way?
For one-way options, check prices for Delta. According to our data, you can fly for as low as £286. Users have also found prices from £294 and £295 on JetBlue and Virgin Atlantic, respectively.
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 holiday 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, January is the cheapest month in which you can book a flight from Ontario to London Heathrow Airport (average of £112). Flying from Ontario to London Heathrow Airport in August is currently the most expensive (average of £164). 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

Deal

Hounslow

Milton Keynes

Gatwick

Luton

Slough

Croydon

Eastbourne

Northampton

Southend-on-Sea

Ilford

Crawley

Hayes

Ipswich

Watford

Wembley

Swindon

Folkestone

Maidstone

Winchester

Browse thousands of different options on Cheapflights for your next trip

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How does Cheapflights help users find flights from Ontario to Heathrow?

When you search for this flight from Ontario to Heathrow, Cheapflights searches on 900+ travel sites to save you time finding great flight deals online. Additionally, we offer filter features so you can choose a preferred cabin class or airline, see different price ranges, and much more so you can book the flight for you.

Why should you use Cheapflights to find cheap flight tickets from Ontario to Heathrow?

It’s simple! Cheapflights, which is free to use for everyone, saves millions of users time and money every year by helping them find the cheapest and most suitable flights from Ontario to Heathrow.

Can Cheapflights find flights from Ontario to Heathrow with no change fees?

Certainly. Search results for flights to Heathrow from Ontario shown to you on Cheapflights can be narrowed down with different useful search filters, which includes flexible booking options.

Can Cheapflights notify me if prices for flights from Ontario to Heathrow become cheaper?

Yes, and it’s super simple to set up. Click the bell icon next to the flight deals above and provide a valid email address to enable Price Alerts. That’s it!

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Cheap flights from Ontario to London Heathrow Airport from £286

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 13/5. Fares are subject to change and may not be available on all flights or dates of travel.

Cheap flight deals from Ontario to Heathrow

Round-trip from

One-way from

Popular in

Cheapest in

Average price

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 30 April 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 30 April 2025.

Cheapflights Fare Finder

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

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 return flight from Ontario to Heathrow. Price data was last updated on 25 April 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 30 April 2025.

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

Read reviews from past customers who have flown Delta, KLM and United Airlines from Ontario to London. Users can see the overall rating for each airline as well as how each is rated 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?

Travelling to a place near Ontario?

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Ontario to Heathrow

See prices for flight routes from nearby airports that may be better suited for you.

Fly with Cheapflights

Find the best flight deals on Cheapflights, where travellers can enjoy low prices and a wide availability of flights to their desired destinations.

How does Cheapflights help users find flights from Ontario to Heathrow?

Why should you use Cheapflights to find cheap flight tickets from Ontario to Heathrow?

Can Cheapflights find flights from Ontario to Heathrow with no change fees?

Can Cheapflights notify me if prices for flights from Ontario to Heathrow become cheaper?

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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 30 April 2025.