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Cheap flights from London Heathrow Airport to Ontario from £381

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 28/8. Fares are subject to change and may not be available on all flights or dates of travel.
LHR — ONT
20 Aug — 27 Aug1
1 adult

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 15 August 2025.

Round-trip from

£406

One-way from

£381

Popular in

August

Cheapest in

February

Average price

£706
British Airways
  • British Airways
  • 7/2-14/2
  • 2 total stops
  • 27h 30m total
  • London to Ontario
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28/8
  • 28/8
  • 2 total stops
  • 25h 40m total
  • London to Ontario
Search Deals
Highest demand for flights based on searches. 8% potential increase in price (£35 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease (£12 potential savings vs. average return price).
Search Deals
Average for round-trip flights in August 2025
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Find flight deals from Heathrow to Ontario

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 15 August 2025.

Thu 11/911:00LHR - ONT
1 stop18h 11mBritish Airways
Thu 18/916:45ONT - LHR
1 stop13h 55mBritish Airways
Deal found 14/8£409
Thu 13/1106:20LHR - ONT
2 stops17h 54mVirgin Atlantic
Sat 29/1113:00ONT - LHR
1 stop13h 00mVirgin Atlantic
Deal found 13/8£412
Thu 11/913:25LHR - ONT
2 stops18h 17mVirgin Atlantic
Thu 18/911:55ONT - LHR
1 stop15h 15mVirgin Atlantic
Deal found 14/8£417
Mon 8/911:15LHR - ONT
1 stop18h 33mBritish Airways
Sat 27/910:53ONT - LHR
1 stop14h 07mBritish Airways
Deal found 13/8£423
Thu 4/911:15LHR - ONT
1 stop15h 01mBritish Airways
Wed 15/1014:51ONT - LHR
1 stop13h 54mBritish Airways
Deal found 14/8£423
Thu 11/912:00LHR - ONT
1 stop14h 54mAmerican Airlines
Wed 24/916:45ONT - LHR
1 stop12h 05mAmerican Airlines
Deal found 14/8£426
Wed 10/906:30LHR - ONT
2 stops18h 41mDelta
Wed 17/911:55ONT - LHR
2 stops15h 30mDelta
Deal found 13/8£427
Sun 24/809:15LHR - ONT
2 stops22h 53mIberia
Tue 9/910:53ONT - LHR
1 stop14h 07mIberia
Deal found 14/8£428
Sun 24/808:40LHR - ONT
2 stops23h 00mDelta
Tue 9/907:05ONT - LHR
2 stops16h 10mDelta
Deal found 14/8£429
Sun 14/906:30LHR - ONT
2 stops23h 53mDelta
Sun 28/911:50ONT - LHR
1 stop18h 25mDelta
Deal found 13/8£433

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 15 August 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

Sat 7/2

10:35-17:53

1 stop15h 18m

Ontario

Sat 14/2

17:03-13:15

1 stop12h 12m

£406

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Tue 10/2

14:55-22:02

1 stop15h 07m

Ontario

Tue 3/3

17:03-13:15

1 stop12h 12m

£406

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Tue 3/2

10:35-17:53

1 stop15h 18m

Ontario

Tue 10/2

17:03-13:15

1 stop12h 12m

£407

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 7/2

06:15-22:02

2 stops23h 47m

Ontario

Sat 21/2

15:05-12:15

1 stop13h 10m

£409

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Fri 26/9

12:00-22:33

1 stop18h 33m

Ontario

Fri 3/10

14:54-14:25

1 stop15h 31m

£409

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Thu 13/11

06:20-16:14

2 stops17h 54m

Ontario

Sat 29/11

13:00-10:00

1 stop13h 00m

£412

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Fri 26/9

18:00-22:41

2 stops36h 41m

Ontario

Fri 3/10

13:15-13:10

2 stops39h 55m

£414

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 13/9

17:25-23:42

2 stops38h 17m

Ontario

Sun 28/9

07:05-13:30

1 stop22h 25m

£414

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 10/11

14:45-22:42

1 stop15h 57m

Ontario

Sat 29/11

13:00-10:00

1 stop13h 00m

£416

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 12/11

10:45-16:14

1 stop13h 29m

Ontario

Sat 29/11

13:00-10:00

1 stop13h 00m

£416

Flights are sorted by cheapest return flights first.

Deals found on 14/8

Showing 1-10 of 21 results
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2
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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 8 August 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 80 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, March is the cheapest month in which you can book a flight from London Heathrow Airport to Ontario (average of £516). Flying from London Heathrow Airport to Ontario in August is currently the most expensive (average of £827). 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 15 August 2025.

It’s optimal to fly from London Heathrow Airport to Ontario in the afternoon. By choosing this option you can save up to 25% on the cost of your flight, compared to a flight at midday.

What’s the top stopover airport for flights from London Heathrow Airport to Ontario?

Share of one-stop return flights from London Heathrow Airport to Ontario chosen by Cheapflights users in the past 12 months, using the same stopover each way.

Seattle (SEA) – chosen by Cheapflights users on 24% of one-stop itineraries from London Heathrow Airport to Ontario on Cheapflights.

What’s the cheapest stopover airport for flights from London Heathrow Airport to Ontario?

Average return fare for one-stop flights from London Heathrow Airport to Ontario, chosen by Cheapflights users in the past 12 months, with the same stopover each way.

Lisbon (LIS) is the most affordable one-stop option, with an average return flight price of £389.

What’s the fastest stopover option from London Heathrow Airport to Ontario?

Shortest average travel time for one-stop one-way flights from London Heathrow Airport to Ontario, based on itineraries clicked by Cheapflights users over the past 12 months, grouped by stopover airport.

Flights via Phoenix (PHX) have the shortest average one-way travel time for one-stop routes: 14h 15m.

Which airport typically offers the quickest stopover for flights from London Heathrow Airport to Ontario?

Average stopover duration for one-stop one-way flights from London Heathrow Airport to Ontario, chosen by Cheapflights users in the last 12 months, grouped by stopover airport.

Flights via Seattle (SEA) offer the fastest connection on this route, with an average stopover time of 1h 19m.

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 15 August 2025.
Read reviews from past customers who have flown with Finnair, United Airlines, andVirgin Atlantic 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.
Finnair
7.6
Good
1,321 reviews
Check prices

Crew

8.1

Comfort

7.5

Overall

7.6

Entertainment

6.9

Boarding

7.6

Food

6.7

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.
Finnair
7.6
Good
1,321 reviews
Finnair
7.6
Good
1,321 reviews
Check prices

Crew

8.1

Comfort

7.5

Overall

7.6

Entertainment

6.9

Boarding

7.6

Food

6.7

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.
United Airlines
7.4
Good
8,915 reviews
Finnair
7.6
Good
1,321 reviews
Check prices

Crew

8.1

Comfort

7.5

Overall

7.6

Entertainment

6.9

Boarding

7.6

Food

6.7

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.
Virgin Atlantic
7.4
Good
657 reviews
Finnair
7.6
Good
1,321 reviews
Check prices

Crew

8.1

Comfort

7.5

Overall

7.6

Entertainment

6.9

Boarding

7.6

Food

6.7

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.
Lufthansa
6.8
Okay
7,321 reviews
Finnair
7.6
Good
1,321 reviews
Check prices

Crew

8.1

Comfort

7.5

Overall

7.6

Entertainment

6.9

Boarding

7.6

Food

6.7

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.
British Airways
6.7
Okay
7,267 reviews
Finnair
7.6
Good
1,321 reviews
Check prices

Crew

8.1

Comfort

7.5

Overall

7.6

Entertainment

6.9

Boarding

7.6

Food

6.7

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.

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.

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

    Currently priced at £355, 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 KLM - these airlines can fly you to your destination from £382 and £390, respectively. Users have found that Finnair is 33% 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, March is the cheapest month in which you can book a flight from London Heathrow Airport to Ontario (average of £516). Flying from London Heathrow Airport to Ontario in August is currently the most expensive (average of £827). 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 15 August 2025.
AirlineCheapestAverageFlexibilityOn-time
FinnairCheapest£355Average£426FlexibilityNo cancel feeOn-time76%
Search Finnair flights
British AirwaysCheapest£382Average£479FlexibilityNo cancel feeOn-time70%
Search British Airways flights
KLMCheapest£390Average£590FlexibilityNo cancel feeOn-time75%
Search KLM flights
United AirlinesCheapest£391Average£636FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
Virgin AtlanticCheapest£403Average£507FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights
LufthansaCheapest£427Average£557FlexibilityNo 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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