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Cheap flights from Ontario to London Heathrow Airport from £294

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 2/5. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — LHR
17 Apr — 24 Apr1
1 adult

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 12 April 2025.

Round-trip from

£456

One-way from

£294

Popular in

June

Cheapest in

March

Average price

£518
Iberia
  • Iberia
  • 28/4-6/5
  • 3 total stops
  • 37h 48m total
  • Ontario to London
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Iberia
  • Iberia
  • 2/5
  • 1 total stop
  • 14h 00m total
  • Ontario to London
Search Deals
Highest demand for flights based on searches. 22% potential increase in price (£138 potential increase over avg. return price).
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Cheapest flight prices on average. 3% potential price decrease (£16 potential savings vs. average return price).
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Average for round-trip flights in April 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 12 April 2025.

Mon 28/412:50ONT - LHR
1 stop14h 00mIberia
Tue 6/506:10LHR - ONT
2 stops23h 48mIberia
Deal found 11/4£456
Thu 6/1108:46ONT - LHR
1 stop13h 34mMultiple Airlines
Wed 12/1108:20LHR - ONT
1 stop17h 29mMultiple Airlines
Deal found 11/4£478
Fri 2/507:00ONT - LHR
1 stop22h 30mVirgin Atlantic
Sun 18/518:30LHR - ONT
1 stop36h 05mVirgin Atlantic
Deal found 11/4£479
Thu 8/506:00ONT - LHR
1 stop21h 20mDelta
Thu 15/509:00LHR - ONT
2 stops21h 35mDelta
Deal found 10/4£479
Sun 27/416:35ONT - LHR
1 stop12h 15mAmerican Airlines
Sat 10/515:40LHR - ONT
1 stop14h 17mAmerican Airlines
Deal found 11/4£482
Sun 4/512:50ONT - LHR
1 stop14h 00mBritish Airways
Mon 19/506:45LHR - ONT
2 stops19h 51mBritish Airways
Deal found 11/4£487
Thu 8/505:05ONT - LHR
2 stops22h 45mAir Canada
Thu 15/509:30LHR - ONT
2 stops43h 23mAir Canada
Deal found 10/4£511
Tue 21/1013:15ONT - LHR
1 stop12h 25mUnited Airlines
Fri 31/1007:30LHR - ONT
2 stops19h 47mUnited Airlines
Deal found 10/4£514
Fri 5/907:00ONT - LHR
1 stop15h 45mAir France
Fri 12/913:05LHR - ONT
1 stop17h 36mAir France
Deal found 11/4£567
Sat 3/522:40ONT - LHR
1 stop14h 05mJetBlue
Tue 13/508:15LHR - ONT
1 stop20h 56mJetBlue
Deal found 11/4£568
Tue 16/923:00ONT - LHR
1 stop13h 45mIcelandair
Tue 14/1008:15LHR - ONT
1 stop21h 26mIcelandair
Deal found 11/4£623
Sat 18/1013:00ONT - LHR
1 stop12h 50mKLM
Sun 26/1012:20LHR - ONT
1 stop17h 22mKLM
Deal found 11/4£655

Cheapflights Fare Finder

Customise 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 858,174 searches. Data last updated 12 April 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

Mon 28/4

12:50-10:50

1 stop14h 00m

London Heathrow

Tue 6/5

06:10-21:58

2 stops23h 48m

£456

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Fri 2/5

07:00-13:30

1 stop22h 30m

London Heathrow

Sun 18/5

18:30-22:35

1 stop36h 05m

£479

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Thu 8/5

06:00-11:20

1 stop21h 20m

London Heathrow

Thu 15/5

09:00-22:35

2 stops21h 35m

£479

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Sun 27/4

16:35-12:50

1 stop12h 15m

London Heathrow

Sat 10/5

15:40-21:57

1 stop14h 17m

£482

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Sun 4/5

12:50-10:50

1 stop14h 00m

London Heathrow

Mon 19/5

06:45-18:36

2 stops19h 51m

£487

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Thu 8/5

05:05-11:50

2 stops22h 45m

London Heathrow

Thu 15/5

09:30-20:53

2 stops43h 23m

£511

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Fri 25/4

13:35-09:40

1 stop12h 05m

London Heathrow

Fri 2/5

09:30-20:34

2 stops19h 04m

£514

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Fri 5/9

07:00-06:45

1 stop15h 45m

London Heathrow

Fri 12/9

13:05-22:41

1 stop17h 36m

£567

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Sat 3/5

22:40-20:45

1 stop14h 05m

London Heathrow

Tue 13/5

08:15-21:11

1 stop20h 56m

£568

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 10/9

10:00-11:50

2 stops17h 50m

London Heathrow

Wed 17/9

09:30-22:53

3 stops21h 23m

£601

Flights are sorted by cheapest return flights first.

Deals found on 11/4

Showing 1-10 of 24 results
1
2
3

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?

Use this chart to determine the optimal time to book a return flight from Ontario to Heathrow. Price data was last updated on 4 April 2025.

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?

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 12 April 2025.

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

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 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

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 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

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 12 April 2025.
Read reviews from past customers who have flown Delta, KLM and Air France 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
7,912 reviews
Check prices

Food

7.3

Overall

8.0

Boarding

8.2

Comfort

7.9

Crew

8.5

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
7,912 reviews
Delta
8.0
Very Good
7,912 reviews
Check prices

Food

7.3

Overall

8.0

Boarding

8.2

Comfort

7.9

Crew

8.5

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
1,321 reviews
Delta
8.0
Very Good
7,912 reviews
Check prices

Food

7.3

Overall

8.0

Boarding

8.2

Comfort

7.9

Crew

8.5

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.
Air France
7.4
Good
1,428 reviews
Delta
8.0
Very Good
7,912 reviews
Check prices

Food

7.3

Overall

8.0

Boarding

8.2

Comfort

7.9

Crew

8.5

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
8,644 reviews
Delta
8.0
Very Good
7,912 reviews
Check prices

Food

7.3

Overall

8.0

Boarding

8.2

Comfort

7.9

Crew

8.5

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
641 reviews
Delta
8.0
Very Good
7,912 reviews
Check prices

Food

7.3

Overall

8.0

Boarding

8.2

Comfort

7.9

Crew

8.5

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?

    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 £456. Other airlines that can offer you cheap pricing are Virgin Atlantic, from £479, and Delta, from £479. Iberia is currently priced 26% 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 Iberia. According to our data, you can fly for as low as £294. Users have also found prices from £302 and £304 on JetBlue and British Airways, 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

Travelling to a place near Ontario?

Book flights to Ontario if you plan to visit one of these locations
Hounslow
Deal
Milton Keynes
Luton
Gatwick
Croydon
Slough
Eastbourne
Northampton
Wembley
Crawley
Hayes
Swindon
Southend-on-Sea
Maidstone
Ilford
Winchester
Ipswich
Southall
Folkestone

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Fly with Cheapflights

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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.

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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.

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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.

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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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