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Cheap flights from London Heathrow Airport to Ontario from £312

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 19/1. Fares are subject to change and may not be available on all flights or dates of travel.
LHR — ONT
18 Dec — 25 Dec1
1 adult
1 adult, Economy, 0 bags

Find flight deals from Heathrow to Ontario

Enter your travel dates to find the best prices.

Cheapest flights from Heathrow to Ontario
Explore the most affordable flight options available from Heathrow to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 18 November 2025.

Fri 26/1206:20LHR - ONT
2 stops25h 34mDelta
Wed 31/1206:00ONT - LHR
2 stops17h 50mDelta
Deal found 17/11£463
Wed 24/1215:50LHR - ONT
1 stop26h 10mDelta
Wed 31/1206:00ONT - LHR
1 stop20h 00mDelta
Deal found 17/11£473
Thu 25/1206:30LHR - ONT
2 stops21h 20mDelta
Thu 1/107:05ONT - LHR
2 stops19h 40mDelta
Deal found 17/11£475
Wed 10/1206:30LHR - ONT
2 stops18h 37mDelta
Tue 16/1207:05ONT - LHR
1 stop15h 20mDelta
Deal found 17/11£476
Tue 9/1206:30LHR - ONT
2 stops18h 37mDelta
Mon 15/1207:05ONT - LHR
1 stop17h 55mDelta
Deal found 16/11£478
Sun 28/1210:45LHR - ONT
1 stop13h 27mVirgin Atlantic
Sat 17/113:10ONT - LHR
1 stop12h 50mVirgin Atlantic
Deal found 16/11£479
Mon 8/1216:10LHR - ONT
2 stops35h 29mAmerican Airlines
Tue 16/1207:00ONT - LHR
2 stops40h 20mAmerican Airlines
Deal found 16/11£481
Mon 15/1214:45LHR - ONT
1 stop16h 02mDelta
Sat 17/113:10ONT - LHR
1 stop12h 50mDelta
Deal found 17/11£482
Sat 13/1215:05LHR - ONT
1 stop15h 42mVirgin Atlantic
Thu 8/112:41ONT - LHR
1 stop14h 59mVirgin Atlantic
Deal found 17/11£483
Mon 15/1211:05LHR - ONT
2 stops20h 53mDelta
Tue 30/1207:05ONT - LHR
2 stops17h 55mDelta
Deal found 16/11£488
Wed 3/1208:55LHR - ONT
1 stop22h 09mDelta
Sun 7/1207:05ONT - LHR
1 stop16h 45mDelta
Deal found 17/11£488
Wed 24/1210:45LHR - ONT
1 stop19h 48mDelta
Tue 30/1213:15ONT - LHR
1 stop12h 45mDelta
Deal found 16/11£489

Cheap flight deals from Heathrow to Ontario

Discover tips and strategies to find the most affordable flight options for your journey from Heathrow (LHR) to Ontario (ONT). 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 18 November 2025.

Round-trip from

£362

One-way from

£312

Popular in

December

Cheapest in

September

Average price

£501
Virgin Atlantic
  • Virgin Atlantic
  • 16/3-4/4
  • 2 total stops
  • 31h 23m total
  • London to Ontario
Search Deals
British Airways
  • British Airways
  • 14/1
  • 2 total stops
  • 23h 13m total
  • London to Ontario
Search Deals
Highest demand for flights based on searches. 6% potential increase in price (£28 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease (£15 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 Heathrow to Ontario 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 18 November 2025.
Use the filters below to find and compare flights from London Heathrow Airport to Ontario that are best for you.

Fly from

Heathrow

Fly to

Ontario

Route

Depart

Return

Price

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Thu 26/2

14:45-22:40

1 stop15h 55m

Ontario

Mon 2/3

15:30-12:50

1 stop13h 20m

£402

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sun 1/2

08:55-21:05

1 stop20h 10m

Ontario

Sun 8/2

12:41-11:40

1 stop14h 59m

£402

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Fri 17/4

11:20-17:16

1 stop13h 56m

Ontario

Wed 29/4

13:00-09:50

1 stop12h 50m

£420

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Thu 12/3

08:55-21:14

1 stop19h 19m

Ontario

Wed 25/3

13:00-09:00

1 stop13h 00m

£422

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Fri 13/3

08:55-21:14

1 stop19h 19m

Ontario

Tue 31/3

11:55-09:00

1 stop13h 05m

£422

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sun 15/3

12:20-22:38

1 stop17h 18m

Ontario

Tue 31/3

11:55-09:00

1 stop13h 05m

£422

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 11/3

12:20-22:38

1 stop17h 18m

Ontario

Wed 25/3

13:00-09:00

1 stop13h 00m

£422

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sun 15/3

12:20-22:38

1 stop17h 18m

Ontario

Sun 29/3

11:55-09:00

1 stop13h 05m

£422

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 11/3

10:45-21:14

1 stop17h 29m

Ontario

Sat 28/3

13:00-08:50

1 stop12h 50m

£422

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 14/3

12:20-22:38

1 stop17h 18m

Ontario

Wed 25/3

11:55-10:30

1 stop15h 35m

£422

Flights are sorted by cheapest return flights first.

Deals found on 16/11

Showing 1-10 of 21 results
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Best time to book a flight from Heathrow to Ontario

Have a flexible travel schedule? Discover the best time to fly to Ontario from Heathrow 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 London Heathrow Airport to Ontario

How far ahead should I book a flight from London Heathrow Airport to Ontario?

Use this chart to determine the optimal time to book a return flight from Heathrow to Ontario. Price data was last updated on 14 November 2025.

To ensure you get the cheapest price possible for a flight from London Heathrow Airport to Ontario, you should look to book at least 66 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 London Heathrow Airport to Ontario?

Currently, December is the cheapest month in which you can book a flight from London Heathrow Airport to Ontario (average of £346). Flying from London Heathrow Airport to Ontario in July is currently the most expensive (average of £416). 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 LHR to ONT?

Find hourly flight availability from Heathrow to Ontario. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 18 November 2025.

It’s optimal to fly from London Heathrow Airport to Ontario in the evening. By choosing this option you can save up to 27% on the cost of your flight, compared to a flight at midday.

Reviews of airlines servicing Ontario

Get insights into the airlines that provide service to Ontario. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Ontario. Reviews last updated 18 November 2025.
Read reviews from past customers who have flown with KLM, Virgin Atlantic, andUnited Airlines from London Heathrow Airport to Ontario. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
KLM
7.7
Good
1,411 reviews
Check prices

Comfort

7.7

Crew

8.4

Boarding

7.8

Entertainment

7.1

Food

7.3

Overall

7.7

Reviews

1 / 20
2.0
Mediocre

Abisola,Oct 2025

LOS - CDG

The food option was finished and what wa left was vegan pasta so I had to go without food for an 8 hour flight without any sort of empathy from crew that was mean.
KLM
7.7
Good
1,411 reviews
KLM
7.7
Good
1,411 reviews
Check prices

Comfort

7.7

Crew

8.4

Boarding

7.8

Entertainment

7.1

Food

7.3

Overall

7.7

Reviews

1 / 20
2.0
Mediocre

Abisola,Oct 2025

LOS - CDG

The food option was finished and what wa left was vegan pasta so I had to go without food for an 8 hour flight without any sort of empathy from crew that was mean.
Virgin Atlantic
7.5
Good
673 reviews
KLM
7.7
Good
1,411 reviews
Check prices

Comfort

7.7

Crew

8.4

Boarding

7.8

Entertainment

7.1

Food

7.3

Overall

7.7

Reviews

1 / 20
2.0
Mediocre

Abisola,Oct 2025

LOS - CDG

The food option was finished and what wa left was vegan pasta so I had to go without food for an 8 hour flight without any sort of empathy from crew that was mean.
United Airlines
7.4
Good
9,014 reviews
KLM
7.7
Good
1,411 reviews
Check prices

Comfort

7.7

Crew

8.4

Boarding

7.8

Entertainment

7.1

Food

7.3

Overall

7.7

Reviews

1 / 20
2.0
Mediocre

Abisola,Oct 2025

LOS - CDG

The food option was finished and what wa left was vegan pasta so I had to go without food for an 8 hour flight without any sort of empathy from crew that was mean.
Lufthansa
6.8
Okay
7,576 reviews
KLM
7.7
Good
1,411 reviews
Check prices

Comfort

7.7

Crew

8.4

Boarding

7.8

Entertainment

7.1

Food

7.3

Overall

7.7

Reviews

1 / 20
2.0
Mediocre

Abisola,Oct 2025

LOS - CDG

The food option was finished and what wa left was vegan pasta so I had to go without food for an 8 hour flight without any sort of empathy from crew that was mean.
British Airways
6.7
Okay
7,529 reviews
KLM
7.7
Good
1,411 reviews
Check prices

Comfort

7.7

Crew

8.4

Boarding

7.8

Entertainment

7.1

Food

7.3

Overall

7.7

Reviews

1 / 20
2.0
Mediocre

Abisola,Oct 2025

LOS - CDG

The food option was finished and what wa left was vegan pasta so I had to go without food for an 8 hour flight without any sort of empathy from crew that was mean.

Related info for your journey

Find useful and relevant information for your journey from Heathrow to Ontario. 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 into for flights to Ontario from London Heathrow?

    If you book a flight to Ontario from London Heathrow, you will be flying to Ontario, which is the city’s only airport. Ontario (ONT) is located 3.1 mi from the center of Ontario. There are 0 flights from London Heathrow to Ontario per day from 6 different airlines.

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

    Delta and KLM can get you from London Heathrow Airport to Ontario in just under 13h 56m. Your travel time can differ by up to 1h 59m. The distance between London Heathrow Airport and Ontario is about 5407 mi. This flight may include one or multiple stops.

  • What are the cheapest airlines flying from London Heathrow Airport to Ontario round-trip?

    Currently priced at £285, Finnair will fly you from London Heathrow Airport to Ontario and back. In addition to Finnair, many other airlines offer competitively priced options for your trip. Search Cheapflights for deals from British Airways and United Airlines - these airlines can fly you to your destination from £393 and £394, respectively. Users have found that Finnair is 49% cheaper than the other options available to this destination.

  • Can I find deals for flights from Heathrow to Ontario that include hotel bookings?

    Yes. In addition to deals on Heathrow to Ontario flights, Cheapflights offers holiday packages that include both flights and hotel.

  • How can I find direct flights from Heathrow to Ontario?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Heathrow to Ontario.

  • Can I find deals for business class flights from Heathrow to Ontario?

    Yes. Cheapflights offers flight deals from Heathrow to Ontario 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 London Heathrow Airport to Ontario?

    Currently, December is the cheapest month in which you can book a flight from London Heathrow Airport to Ontario (average of £346). Flying from London Heathrow Airport to Ontario in July is currently the most expensive (average of £416). 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

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Alternative routes for Heathrow to Ontario

See prices for flight routes from nearby airports that may be better suited for you.
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Top 6 airlines flying from Heathrow to Ontario

Discover the top 6 airlines that operate flights from Heathrow to Ontario. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 858,174 searches. Data last updated 18 November 2025.
AirlineCheapestAverageFlexibilityOn-time
FinnairCheapest£285Average£505FlexibilityNo cancel feeOn-time76%
Search Finnair flights
British AirwaysCheapest£393Average£475FlexibilityNo cancel feeOn-time70%
Search British Airways flights
United AirlinesCheapest£394Average£655FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
KLMCheapest£402Average£610FlexibilityNo cancel feeOn-time75%
Search KLM flights
Virgin AtlanticCheapest£417Average£516FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights
LufthansaCheapest£440Average£591FlexibilityNo cancel feeOn-time76%
Search Lufthansa flights

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 Heathrow to Ontario?

Cheapflights goes through 900+ travel sites to look for the best flight deals for flights from Heathrow to Ontario. Too many options? Cheapflights also provides filters for things like airlines, price ranges, and number of stops to help you make a decision easily.

Why should you use Cheapflights to find cheap flight tickets from Heathrow to Ontario?

Cheapflights taps into our reliable network of hundreds of airlines and travel agencies to find the best deals for flights from Heathrow to Ontario for you. Better yet — we are completely free to use.

Can Cheapflights find flights from Heathrow to Ontario with no change fees?

Yes! Cheapflights helps users easily find flights from Heathrow to Ontario with no change fees.

Can Cheapflights notify me if prices for flights from Heathrow to Ontario become cheaper?

Yes, Cheapflights offers price alerts on Heathrow to Ontario flights so you can book your travel at the perfect time. Price Alerts can be enabled by clicking the bell icon next to the flight deals above and providing your email address where you want to receive the alerts.

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