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Cheap flights from Ontario to London Heathrow Airport from £317

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 11/7. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — LHR
13 Jun — 20 Jun1
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 14 May 2026.

Mon 19/1013:31
ONT
-
LHR
1 stop12h 59m
British Airways
Fri 30/1014:25
LHR
-
ONT
1 stop14h 10m
British Airways
Deal found 12/5£660
Tue 3/1110:47
ONT
-
LHR
1 stop13h 28m
Iberia
Tue 10/1106:00
LHR
-
ONT
2 stops24h 23m
Iberia
Deal found 11/5£663
Mon 17/811:55
ONT
-
LHR
1 stop16h 15m
Delta
Wed 2/906:30
LHR
-
ONT
2 stops19h 31m
Delta
Deal found 13/5£663
Mon 17/807:05
ONT
-
LHR
1 stop15h 20m
Virgin Atlantic
Wed 2/909:55
LHR
-
ONT
2 stops21h 49m
Virgin Atlantic
Deal found 13/5£664
Mon 3/809:43
ONT
-
LHR
2 stops19h 32m
Virgin Atlantic
Fri 28/806:30
LHR
-
ONT
2 stops24h 15m
Virgin Atlantic
Deal found 9/5£666
Mon 3/822:00
ONT
-
LHR
1 stop24h 25m
Delta
Thu 20/806:15
LHR
-
ONT
2 stops18h 09m
Delta
Deal found 11/5£668
Tue 3/1116:47
ONT
-
LHR
1 stop12h 28m
British Airways
Thu 12/1115:00
LHR
-
ONT
1 stop15h 23m
British Airways
Deal found 10/5£674
Sat 22/813:56
ONT
-
LHR
2 stops23h 24m
United Airlines
Tue 8/907:30
LHR
-
ONT
2 stops22h 29m
United Airlines
Deal found 13/5£675
Sun 23/805:00
ONT
-
LHR
2 stops17h 35m
Air Canada
Tue 8/914:05
LHR
-
ONT
2 stops38h 47m
Air Canada
Deal found 11/5£676

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 14 May 2026.

Round-trip from

£660

One-way from

£317

Popular in

June

Cheapest in

November

Average price

£766
British Airways
  • British Airways
  • 19/10-30/10
  • 2 total stops
  • 27h 09m total
  • Ontario to London
Search Deals
JetBlue
  • JetBlue
  • 11/7
  • 1 total stop
  • 13h 21m total
  • Ontario to London
Search Deals
Highest demand for flights based on searches. 30% potential increase in price (£212 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 May 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 14 May 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 17/8

09:43-10:00

1 stop16h 17m

London Heathrow

Wed 2/9

09:55-23:44

2 stops21h 49m

£663

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Mon 3/8

18:01-15:35

1 stop13h 34m

London Heathrow

Thu 20/8

06:30-21:52

2 stops23h 22m

£663

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Mon 2/11

14:59-12:00

1 stop13h 01m

London Heathrow

Wed 18/11

16:30-23:57

1 stop15h 27m

£685

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 26/8

09:01-07:25

1 stop14h 24m

London Heathrow

Tue 8/9

14:50-20:52

1 stop14h 02m

£685

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Mon 3/8

13:10-15:05

1 stop17h 55m

London Heathrow

Thu 20/8

10:05-18:47

1 stop16h 42m

£685

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Sat 17/10

17:50-12:10

1 stop34h 20m

London Heathrow

Mon 2/11

12:20-22:43

1 stop18h 23m

£726

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Thu 13/8

12:33-10:55

1 stop14h 22m

London Heathrow

Sat 22/8

12:55-21:12

1 stop16h 17m

£759

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Sat 5/9

13:18-09:40

1 stop12h 22m

London Heathrow

Sat 3/10

14:50-20:52

1 stop14h 02m

£759
Fastest return journey

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Thu 9/7

13:18-09:40

1 stop12h 22m

London Heathrow

Thu 16/7

14:50-20:42

1 stop13h 52m

£884

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Thu 2/7

13:18-12:25

1 stop15h 07m

London Heathrow

Wed 15/7

14:50-20:42

1 stop13h 52m

£908

Flights are sorted by cheapest return flights first.

Deals found on 12/5

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, November is the cheapest month in which you can book a flight from Ontario to London Heathrow Airport (average of £461). Flying from Ontario to London Heathrow Airport in June is currently the most expensive (average of £1,177). 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?

    Virgin Atlantic, Delta, and British Airways can get you from Ontario to London Heathrow Airport in just under 13h 01m. Your travel time can differ by up to 3h 16m. 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 £461). Flying from Ontario to London Heathrow Airport in June is currently the most expensive (average of £1,177). 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
Hounslow
Croydon
Wembley
Northampton
Luton
Gatwick
Slough
Ilford
Hayes
Brentford
Colchester
Romford
Watford
Kingston upon Thames
Eastbourne
Swindon
Ipswich
Southend-on-Sea
Guildford

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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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