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Cheap flights from Ontario to London Heathrow Airport from £271

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 16/5. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — LHR
8 Apr — 15 Apr1
1 adult
1 adult, Economy, 0 bags

Cheap 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 9 March 2026.

Mon 27/406:00
ONT
-
LHR
2 stops23h 05m
Virgin Atlantic
Wed 13/511:45
LHR
-
ONT
2 stops18h 49m
Virgin Atlantic
Deal found 4/3£468
Mon 2/1112:55
ONT
-
LHR
1 stop16h 20m
Multiple Airlines
Tue 10/1115:00
LHR
-
ONT
1 stop15h 23m
Multiple Airlines
Deal found 4/3£539
Mon 6/414:39
ONT
-
LHR
1 stop15h 46m
Iberia
Wed 22/411:30
LHR
-
ONT
2 stops20h 16m
Iberia
Deal found 7/3£545
Mon 2/1118:53
ONT
-
LHR
2 stops17h 42m
United Airlines
Tue 10/1107:30
LHR
-
ONT
2 stops21h 51m
United Airlines
Deal found 4/3£548
Mon 6/422:25
ONT
-
LHR
2 stops24h 45m
KLM
Wed 22/411:45
LHR
-
ONT
2 stops19h 59m
KLM
Deal found 7/3£549
Tue 7/410:59
ONT
-
LHR
1 stop13h 06m
British Airways
Fri 17/410:50
LHR
-
ONT
2 stops20h 56m
British Airways
Deal found 6/3£551
Wed 8/410:59
ONT
-
LHR
1 stop17h 11m
Iberia
Fri 17/410:50
LHR
-
ONT
2 stops20h 56m
Iberia
Deal found 6/3£551
Tue 21/410:59
ONT
-
LHR
1 stop13h 06m
Iberia
Tue 28/420:00
LHR
-
ONT
2 stops35h 46m
Iberia
Deal found 7/3£554
Tue 14/414:08
ONT
-
LHR
1 stop16h 17m
Iberia
Tue 21/406:10
LHR
-
ONT
2 stops22h 44m
Iberia
Deal found 9/3£554
Wed 15/411:53
ONT
-
LHR
1 stop16h 17m
Delta
Tue 5/511:45
LHR
-
ONT
2 stops18h 52m
Delta
Deal found 9/3£555

Find 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 9 March 2026.

Round-trip from

£468

One-way from

£271

Popular in

June

Cheapest in

November

Average price

£597
Virgin Atlantic
  • Virgin Atlantic
  • 27/4-13/5
  • 4 total stops
  • 41h 54m total
  • Ontario to London
Search Deals
JetBlue
  • JetBlue
  • 16/5
  • 1 total stop
  • 13h 20m total
  • Ontario to London
Search Deals
Highest demand for flights based on searches. 23% potential increase in price (£146 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 6% potential price decrease (£28 potential savings vs. average return price).
Search Deals
Average for round-trip flights in March 2026
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 9 March 2026.
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

Cheapest return flight

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 25/3

06:00-10:15

1 stop21h 15m

London Heathrow

Tue 7/4

07:30-21:50

2 stops22h 20m

£563
Fastest return journey

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Tue 24/3

12:57-09:00

1 stop13h 03m

London Heathrow

Tue 31/3

10:55-16:28

1 stop13h 33m

£564

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Mon 23/3

13:50-09:40

1 stop12h 50m

London Heathrow

Tue 7/4

14:50-20:36

1 stop13h 46m

£569

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 15/4

13:27-11:10

1 stop13h 43m

London Heathrow

Tue 5/5

10:35-17:52

1 stop15h 17m

£576

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 2/9

13:18-12:20

1 stop15h 02m

London Heathrow

Tue 15/9

14:50-20:52

1 stop14h 02m

£576

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Fri 7/8

21:13-15:05

1 stop33h 52m

London Heathrow

Fri 28/8

17:00-11:09

1 stop26h 09m

£586

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Sun 5/4

13:27-11:10

1 stop13h 43m

London Heathrow

Sun 12/4

13:40-21:50

1 stop16h 10m

£613

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Thu 23/4

13:29-13:05

2 stops15h 36m

London Heathrow

Mon 4/5

06:30-21:00

2 stops22h 30m

£633

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Sun 9/8

17:38-15:05

1 stop13h 27m

London Heathrow

Tue 18/8

17:00-23:11

1 stop14h 11m

£643

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Fri 1/5

05:00-09:40

1 stop20h 40m

London Heathrow

Tue 5/5

09:30-20:36

2 stops19h 06m

£676

Flights are sorted by cheapest return flights first.

Deals found on 4/3

Showing 1-10 of 24 resultsSorted by cheapest first
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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

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

Currently, December is the cheapest month in which you can book a flight from Ontario to London Heathrow Airport (average of £350). Flying from Ontario to London Heathrow Airport in June is currently the most expensive (average of £521). 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.

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?

    United Airlines and Alaska Airlines can get you from Ontario to London Heathrow Airport in just under 14h 40m. Your travel time can differ by up to 25m. 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, December is the cheapest month in which you can book a flight from Ontario to London Heathrow Airport (average of £350). Flying from Ontario to London Heathrow Airport in June is currently the most expensive (average of £521). 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
Wembley
Croydon
Northampton
Luton
Hounslow
Slough
Gatwick
Ilford
Hayes
Brentford
Colchester
Guildford
Watford
Kingston upon Thames
Chelmsford
Eastbourne
Ipswich
Swindon
Bedford

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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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