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Cheap flights from Ontario to London Heathrow Airport from £226

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 13/1. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — LHR
6 Dec — 13 Dec1
1 adult
1 adult, Economy, 0 bags

Find flight deals from Ontario to Heathrow

Enter your travel dates to find the best prices.

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 6 November 2025.

Tue 2/1206:40ONT - LHR
1 stop22h 10mVirgin Atlantic
Tue 16/1214:45LHR - ONT
1 stop16h 02mVirgin Atlantic
Deal found 5/11£449
Wed 3/1206:00ONT - LHR
1 stop20h 00mDelta
Wed 10/1206:30LHR - ONT
2 stops18h 37mDelta
Deal found 5/11£466
Tue 2/1212:40ONT - LHR
1 stop13h 50mDelta
Tue 9/1206:30LHR - ONT
2 stops24h 34mDelta
Deal found 4/11£467
Sun 9/1112:16ONT - LHR
1 stop15h 24mDelta
Tue 25/1108:55LHR - ONT
1 stop18h 47mDelta
Deal found 4/11£472
Tue 11/1116:47ONT - LHR
1 stop12h 28mBritish Airways
Tue 25/1116:30LHR - ONT
1 stop15h 27mBritish Airways
Deal found 4/11£475
Tue 18/1113:20ONT - LHR
1 stop12h 40mDelta
Thu 27/1106:30LHR - ONT
2 stops21h 12mDelta
Deal found 4/11£476
Sun 9/1112:53ONT - LHR
1 stop13h 07mIberia
Tue 25/1116:30LHR - ONT
1 stop15h 27mIberia
Deal found 6/11£477

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 6 November 2025.

Round-trip from

£449

One-way from

£226

Popular in

June

Cheapest in

September

Average price

£648
Virgin Atlantic
  • Virgin Atlantic
  • 2/12-16/12
  • 2 total stops
  • 38h 12m total
  • Ontario to London
Search Deals
13/1
  • 13/1
  • 3 total stops
  • 43h 59m total
  • Ontario to London
Search Deals
Highest demand for flights based on searches. 22% potential increase in price (£148 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 5% potential price decrease (£25 potential savings vs. average return price).
Search Deals
Average for round-trip flights in November 2025
Search Deals

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 6 November 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

Wed 3/12

06:00-07:05

2 stops17h 05m

London Heathrow

Wed 10/12

06:30-19:39

2 stops21h 09m

£470

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Mon 5/1

15:30-12:50

1 stop13h 20m

London Heathrow

Tue 20/1

08:40-21:07

2 stops20h 27m

£473

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 3/12

06:00-10:00

1 stop20h 00m

London Heathrow

Wed 10/12

08:55-23:04

1 stop22h 09m

£479

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Mon 5/1

18:39-09:40

2 stops55h 01m

London Heathrow

Tue 20/1

06:30-21:58

2 stops23h 28m

£480

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Fri 9/1

05:05-05:55

2 stops16h 50m

London Heathrow

Sun 18/1

08:30-21:58

2 stops21h 28m

£481

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Tue 2/12

06:00-10:00

1 stop20h 00m

London Heathrow

Tue 16/12

11:05-23:04

2 stops19h 59m

£483

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Fri 9/1

06:00-08:45

2 stops18h 45m

London Heathrow

Sun 18/1

06:30-22:29

2 stops23h 59m

£484

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Sun 7/12

12:46-11:40

1 stop14h 54m

London Heathrow

Sun 14/12

16:30-23:55

1 stop15h 25m

£488

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Mon 9/2

16:45-13:15

1 stop12h 30m

London Heathrow

Sun 15/2

14:20-22:08

1 stop15h 48m

£488

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Tue 17/2

05:00-09:40

1 stop20h 40m

London Heathrow

Sun 22/2

09:30-21:59

2 stops20h 29m

£488

Flights are sorted by cheapest return flights first.

Deals found on 5/11

Showing 1-10 of 21 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 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 31 October 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 62 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 £335). Flying from Ontario to London Heathrow Airport in June is currently the most expensive (average of £537). 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 6 November 2025.

Unlike at midday, when flights are generally more expensive, you can save up to 5% on flights from Ontario to London Heathrow Airport by exploring options for tickets in the afternoon.

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.

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

    Delta, KLM, and United Airlines can get you from Ontario to London Heathrow Airport in just under 17h 05m. Your travel time can differ by up to 37h 56m. The distance between Ontario and London Heathrow Airport is about 5407 mi. This flight may include one or multiple stops.

  • 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 £335). Flying from Ontario to London Heathrow Airport in June is currently the most expensive (average of £537). 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 London Heathrow Airport?

Book flights to London Heathrow Airport if you plan to visit one of these locations
Milton Keynes
Croydon
Slough
Gatwick
Hounslow
Northampton
Luton
Ilford
Wembley
Deal
Hayes
Colchester
Watford
Winchester
Swindon
Crawley
Brentford
Romford
Chichester
Ipswich

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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?

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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