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Cheap flights from Ontario to London Heathrow Airport from £233

ONT — LHR
4 Oct — 11 Oct1
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

Wed 9/1205:00 -
2 stops20h 20m
Thu 17/1214:45 -
1 stop17h 11m
Deal found 3/9£594
Tue 1/1210:37 -
1 stop13h 38m
Tue 8/1214:45 -
1 stop15h 54m
Deal found 2/9£597
Sun 29/1110:37 -
1 stop13h 38m
Sun 6/1214:45 -
1 stop28h 24m
Deal found 31/8£603
Wed 9/1211:26 -
2 stops16h 24m
Wed 16/1213:25 -
2 stops30h 26m
Deal found 2/9£606
Fri 16/1023:05 -
1 stop13h 40m
Fri 23/1017:00 -
1 stop28h 16m
Deal found 1/9£616
Tue 8/1214:22 -
1 stop13h 38m
Sun 27/1214:45 -
1 stop15h 17m
Deal found 1/9£628
Thu 10/1205:00 -
2 stops22h 50m
Thu 17/1214:45 -
1 stop17h 11m
Deal found 3/9£631
Mon 19/1023:05 -
1 stop13h 40m
Mon 2/1118:00 -
2 stops29h 33m
Deal found 3/9£639
Mon 14/1212:00 -
1 stop16h 20m
Mon 28/1214:45 -
1 stop15h 17m
Deal found 2/9£642
Mon 28/922:39 -
1 stop14h 06m
Fri 2/1008:15 -
1 stop20h 42m
Deal found 1/9£648

Find flight deals from Ontario to Heathrow

Round-trip from

£590

One-way from

£233

Popular in

June

Cheapest in

November

Average price

£751
Alaska Airlines
  • Alaska Airlines
  • 2/3-13/3
  • 2 total stops
  • 32h 14m total
  • Ontario to London
Search Deals
JetBlue
  • JetBlue
  • 26/9-31/12
  • 1 total stop
  • 14h 06m total
  • Ontario to London
Search Deals
Highest demand for flights based on searches. 27% potential increase in price (£212 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 5% potential price decrease (£29 potential savings vs. average return price).
Search Deals
Average for round-trip flights in September 2026
Search Deals

Cheapflights Fare Finder

 
Use the filters below to find and compare flights from Ontario to London Heathrow Airport that are best for you.

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Route

Depart

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Price

Cheapest return flight
Fastest return journey

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Tue 13/10

23:05-20:45

1 stop13h 40m

London Heathrow

Wed 31/12

00:00-15:00

Nonstop0h 00m

£243

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Mon 12/10

23:05-20:45

1 stop13h 40m

London Heathrow

Wed 31/12

00:00-15:00

Nonstop0h 00m

£243

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Sat 10/10

23:05-20:45

1 stop13h 40m

London Heathrow

Wed 31/12

00:00-15:00

Nonstop0h 00m

£243

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Mon 28/9

22:39-20:45

1 stop14h 06m

London Heathrow

Wed 31/12

00:00-15:00

Nonstop0h 00m

£243

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Tue 6/10

22:42-20:45

1 stop14h 03m

London Heathrow

Wed 31/12

00:00-15:00

Nonstop0h 00m

£243

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Sat 16/1

11:20-07:25

1 stop36h 05m

London Heathrow

Wed 31/12

00:00-15:00

Nonstop0h 00m

£248

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Wed 7/10

22:42-20:45

1 stop14h 03m

London Heathrow

Wed 31/12

00:00-15:00

Nonstop0h 00m

£258

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Fri 16/10

23:05-20:45

1 stop13h 40m

London Heathrow

Wed 31/12

00:00-15:00

Nonstop0h 00m

£258

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Sun 8/11

06:00-11:15

1 stop21h 15m

London Heathrow

Wed 31/12

00:00-15:00

Nonstop0h 00m

£342

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Mon 15/2

06:00-12:20

1 stop22h 20m

London Heathrow

Thu 11/3

14:45-22:39

1 stop15h 54m

£649

Flights are sorted by cheapest return flights first.

Deals found on 3/9

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

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 £492). 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?

Airfare is below average for this route at the moment.

Ontario to London Heathrow Airport flights typically cost between £674 and £847 in March.
The cheapest return price found within the last 5 days was £590 on Alaska Airlines (2 Mar–13 Mar).

Related info for your journey

  • 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?

    Alaska Airlines, JetBlue, and United Airlines can get you from Ontario to London Heathrow Airport in just under 14h 06m. Your travel time can differ by up to 2h 14m. 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 £492). 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
Hounslow
Milton Keynes
Luton
Gatwick
Wembley
Slough
Ilford
Hayes
Croydon
Northampton
Colchester
Eastbourne
Brentford
Barnet
Salisbury
Southall
Southend-on-Sea
Enfield
Kingston upon Thames
Watford

Browse thousands of different options on Cheapflights for your next trip

Fly with Cheapflights

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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