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Cheap flights from Ontario to London Heathrow Airport from £239

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 11/10. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — LHR
7 Jul — 14 Jul1
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 7 June 2026.

Wed 7/1012:35
ONT
-
LHR
1 stop17h 50m
Iberia
Tue 13/1011:30
LHR
-
ONT
2 stops19h 36m
Iberia
Deal found 6/6£618
Sun 27/913:05
ONT
-
LHR
1 stop18h 00m
Multiple Airlines
Wed 7/1010:50
LHR
-
ONT
2 stops20h 16m
Multiple Airlines
Deal found 3/6£619
Tue 6/1010:25
ONT
-
LHR
1 stop20h 00m
Multiple Airlines
Thu 15/1010:50
LHR
-
ONT
2 stops20h 16m
Multiple Airlines
Deal found 5/6£620
Mon 21/910:25
ONT
-
LHR
1 stop14h 40m
British Airways
Tue 29/908:55
LHR
-
ONT
1 stop19h 14m
British Airways
Deal found 6/6£621
Mon 7/1212:00
ONT
-
LHR
1 stop16h 20m
Multiple Airlines
Sun 13/1214:20
LHR
-
ONT
1 stop15h 40m
Multiple Airlines
Deal found 3/6£621
Wed 11/1110:47
ONT
-
LHR
1 stop17h 28m
Multiple Airlines
Wed 18/1119:40
LHR
-
ONT
2 stops34h 43m
Multiple Airlines
Deal found 2/6£623
Sun 11/1005:00
ONT
-
LHR
1 stop20h 40m
United Airlines
Tue 13/1007:30
LHR
-
ONT
2 stops21h 01m
United Airlines
Deal found 5/6£624
Mon 21/909:01
ONT
-
LHR
2 stops16h 34m
Multiple Airlines
Tue 29/916:25
LHR
-
ONT
1 stop25h 04m
Multiple Airlines
Deal found 6/6£627
Tue 1/906:00
ONT
-
LHR
2 stops16h 35m
Multiple Airlines
Sat 12/908:55
LHR
-
ONT
1 stop21h 42m
Multiple Airlines
Deal found 4/6£627
Wed 14/1013:52
ONT
-
LHR
2 stops15h 28m
Multiple Airlines
Thu 29/1014:45
LHR
-
ONT
1 stop15h 57m
Multiple Airlines
Deal found 5/6£628
Sat 5/914:43
ONT
-
LHR
1 stop31h 37m
Multiple Airlines
Thu 10/916:10
LHR
-
ONT
1 stop14h 33m
Multiple Airlines
Deal found 5/6£629

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 7 June 2026.

Round-trip from

£618

One-way from

£239

Popular in

June

Cheapest in

November

Average price

£1,193
Iberia
  • Iberia
  • 7/10-13/10
  • 3 total stops
  • 37h 26m total
  • Ontario to London
Search Deals
British Airways
  • British Airways
  • 11/10
  • 1 total stop
  • 12h 59m total
  • Ontario to London
Search Deals
Highest demand for flights based on searches. 32% potential increase in price (£241 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 7% potential price decrease (£35 potential savings vs. average return price).
Search Deals
Average for round-trip flights in June 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 7 June 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

Mon 3/8

06:00-10:00

1 stop20h 00m

London Heathrow

Thu 20/8

06:30-21:52

2 stops23h 22m

£649

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Thu 30/7

11:59-15:35

1 stop19h 36m

London Heathrow

Mon 24/8

20:55-16:24

2 stops27h 29m

£708

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 2/9

13:56-11:10

1 stop13h 14m

London Heathrow

Mon 7/9

13:00-20:01

1 stop15h 01m

£709

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Mon 27/7

13:18-09:40

1 stop12h 22m

London Heathrow

Wed 12/8

14:50-20:53

1 stop14h 03m

£719

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 22/7

07:05-13:15

1 stop22h 10m

London Heathrow

Wed 29/7

08:55-22:52

2 stops21h 57m

£766

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Fri 20/11

12:00-12:20

1 stop16h 20m

London Heathrow

Mon 30/11

14:45-11:09

1 stop28h 24m

£797

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Fri 7/8

12:55-10:00

1 stop13h 05m

London Heathrow

Sun 23/8

10:55-16:24

1 stop13h 29m

£857
Fastest return journey

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Fri 10/7

13:18-09:40

1 stop12h 22m

London Heathrow

Wed 15/7

14:50-20:42

1 stop13h 52m

£866

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Fri 17/7

17:26-15:05

1 stop13h 39m

London Heathrow

Wed 29/7

17:00-23:11

1 stop14h 11m

£866

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Fri 3/7

06:00-06:45

2 stops16h 45m

London Heathrow

Fri 10/7

09:30-20:42

2 stops19h 12m

£869

Flights are sorted by cheapest return flights first.

Deals found on 2/6

Showing 1-10 of 21 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, November is the cheapest month in which you can book a flight from Ontario to London Heathrow Airport (average of £468). Flying from Ontario to London Heathrow Airport in June is currently the most expensive (average of £1,193). 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.

How much does it cost for a return flight from Ontario to London Heathrow Airport?

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, Virgin Atlantic, and United Airlines can get you from Ontario to London Heathrow Airport in just under 13h 14m. Your travel time can differ by up to 6h 46m. 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, November is the cheapest month in which you can book a flight from Ontario to London Heathrow Airport (average of £468). Flying from Ontario to London Heathrow Airport in June is currently the most expensive (average of £1,193). 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
Hounslow
Milton Keynes
Wembley
Luton
Gatwick
Croydon
Ilford
Slough
Northampton
Hayes
Brentford
Colchester
Kingston upon Thames
Eastbourne
Watford
Swindon
Ipswich
Romford
Guildford
Poole

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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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