Find flights
When to book
Airlines
FAQs

Cheap flights from London Heathrow Airport to Ontario from £379

This is the cheapest retur flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 4/11. Fares are subject to change and may not be available on all flights or dates of travel.
LHR — ONT
23 Jun — 30 Jun1
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 18 June 2025.

Round-trip from

£379

Popular in

August

Cheapest in

February

Average price

£529
British Airways
  • British Airways
  • 4/11-25/11
  • 2 total stops
  • 27h 24m total
  • London to Ontario
Search Deals
Highest demand for flights based on searches. 3% potential increase in price (£12 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease (£13 potential savings vs. average return price).
Search Deals
Average for round-trip flights in June 2025
Search Deals

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 18 June 2025.

Tue 4/1114:55LHR - ONT
1 stop15h 05mBritish Airways
Tue 25/1117:01ONT - LHR
1 stop12h 19mBritish Airways
Deal found 17/6£379
Sat 1/1106:20LHR - ONT
2 stops23h 26mVirgin Atlantic
Sat 8/1113:00ONT - LHR
1 stop13h 00mVirgin Atlantic
Deal found 16/6£384
Mon 24/1106:30LHR - ONT
2 stops18h 47mDelta
Fri 5/1211:29ONT - LHR
1 stop15h 31mDelta
Deal found 18/6£395
Thu 30/1009:20LHR - ONT
1 stop17h 22mKLM
Wed 12/1112:00ONT - LHR
1 stop14h 35mKLM
Deal found 17/6£409
Sat 23/812:00LHR - ONT
1 stop14h 24mAmerican Airlines
Thu 4/912:46ONT - LHR
1 stop14h 04mAmerican Airlines
Deal found 16/6£428
Tue 15/710:05LHR - ONT
2 stops19h 33mFinnair
Mon 21/700:59ONT - LHR
2 stops21h 56mFinnair
Deal found 16/6£447
Tue 15/709:15LHR - ONT
1 stop20h 23mMultiple Airlines
Tue 22/710:53ONT - LHR
1 stop14h 07mMultiple Airlines
Deal found 17/6£461
Fri 4/710:30LHR - ONT
1 stop16h 31mIberia
Tue 8/712:46ONT - LHR
1 stop17h 39mIberia
Deal found 17/6£486
Wed 29/1015:00LHR - ONT
2 stops38h 45mAir Canada
Wed 5/1105:40ONT - LHR
2 stops21h 40mAir Canada
Deal found 16/6£510
Fri 26/914:50LHR - ONT
1 stop13h 34mUnited Airlines
Wed 8/1013:53ONT - LHR
1 stop12h 32mUnited Airlines
Deal found 17/6£528
Thu 11/908:15LHR - ONT
1 stop21h 14mJetBlue
Sun 21/922:56ONT - LHR
1 stop13h 49mJetBlue
Deal found 18/6£566

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 June 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

Tue 4/11

14:55-22:00

1 stop15h 05m

Ontario

Tue 25/11

17:01-13:20

1 stop12h 19m

£379

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 1/11

06:20-22:46

2 stops23h 26m

Ontario

Sat 8/11

13:00-10:00

1 stop13h 00m

£384

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 24/11

06:30-22:42

2 stops24h 12m

Ontario

Fri 5/12

06:00-12:15

2 stops22h 15m

£395

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Thu 30/10

09:20-19:42

1 stop17h 22m

Ontario

Wed 12/11

12:00-10:35

1 stop14h 35m

£409

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 23/8

12:00-18:24

1 stop14h 24m

Ontario

Thu 4/9

12:46-10:50

1 stop14h 04m

£428

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Tue 15/7

10:05-21:38

2 stops19h 33m

Ontario

Tue 22/7

08:15-06:25

1 stop14h 10m

£447

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Tue 15/7

09:15-21:38

1 stop20h 23m

Ontario

Tue 22/7

10:53-09:00

1 stop14h 07m

£461

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Fri 4/7

10:30-19:01

1 stop16h 31m

Ontario

Tue 8/7

12:46-14:25

1 stop17h 39m

£486

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 29/10

15:00-22:45

2 stops38h 45m

Ontario

Wed 5/11

05:40-11:20

2 stops21h 40m

£510

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Fri 26/9

14:50-20:24

1 stop13h 34m

Ontario

Wed 8/10

13:53-10:25

1 stop12h 32m

£528

Flights are sorted by cheapest return flights first.

Deals found on 17/6

Showing 1-10 of 20 results
1
2

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 13 June 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 27 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 18 June 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.

Rainfall in Ontario by month

Plan your trip to Ontario by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Ontario ranges from 3.0 - 86.0 inches per month. February is typically the wettest month, when rainfall can reach 86.0 mm. June is typically the driest time to visit Ontario when rainfall is around 3.0 mm.

Temperature in Ontario by month

Plan your trip to Ontario by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Ontario, use this chart to help with planning. For those seeking warmer temperatures, August is the ideal time of year to visit, when temperatures reach an average of 26.0 C. Travellers hoping to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 12.0 C).

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 June 2025.
Read through reviews of airlines operating flights from London to Ontario, such as Delta, KLM and Finnair. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very Good
7,964 reviews
Check prices

Food

7.3

Comfort

7.9

Entertainment

7.9

Crew

8.5

Boarding

8.2

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Delta
8.0
Very Good
7,964 reviews
Delta
8.0
Very Good
7,964 reviews
Check prices

Food

7.3

Comfort

7.9

Entertainment

7.9

Crew

8.5

Boarding

8.2

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
KLM
7.8
Good
1,365 reviews
Delta
8.0
Very Good
7,964 reviews
Check prices

Food

7.3

Comfort

7.9

Entertainment

7.9

Crew

8.5

Boarding

8.2

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Finnair
7.6
Good
1,292 reviews
Delta
8.0
Very Good
7,964 reviews
Check prices

Food

7.3

Comfort

7.9

Entertainment

7.9

Crew

8.5

Boarding

8.2

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
United Airlines
7.4
Good
8,810 reviews
Delta
8.0
Very Good
7,964 reviews
Check prices

Food

7.3

Comfort

7.9

Entertainment

7.9

Crew

8.5

Boarding

8.2

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Virgin Atlantic
7.4
Good
653 reviews
Delta
8.0
Very Good
7,964 reviews
Check prices

Food

7.3

Comfort

7.9

Entertainment

7.9

Crew

8.5

Boarding

8.2

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

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 £379, British Airways will fly you from London Heathrow Airport to Ontario and back. In addition to British Airways, many other airlines offer competitively priced options for your trip. Search Cheapflights for deals from Virgin Atlantic and Delta - these airlines can fly you to your destination from £384 and £395, respectively. Users have found that British Airways is 29% cheaper than the other options available to this destination.

  • What are the cheapest airlines to fly from London Heathrow Airport to Ontario one-way?

    To fly one-way, consider booking your trip with Iberia, which is currently one of the cheapest options available, starting at £421. British Airways flights start at £444 while deals on JetBlue start at £588 one-way.

  • 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

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Heathrow to Ontario

See prices for flight routes from nearby airports that may be better suited for you.
Heathrow to Los Angeles flights
Heathrow to San Francisco flights
London City to Los Angeles flights
Heathrow to Las Vegas flights
Gatwick to Los Angeles flights
Luton to Los Angeles flights
Heathrow to Santa Ana flights
Gatwick to San Francisco flights
Heathrow to Long Beach flights
London City to San Francisco flights
Stansted to Los Angeles flights
Heathrow to San Diego flights
Heathrow to Burbank flights
Gatwick to Las Vegas flights
London City to Las Vegas flights
Heathrow to San Jose flights
Heathrow to Oakland flights
Gatwick to Santa Ana flights
Gatwick to Burbank flights
Luton to San Francisco flights
Gatwick to San Jose flights
Gatwick to Oakland flights
Stansted to San Francisco flights
Gatwick to San Diego flights
London City to Santa Ana flights
Luton to Las Vegas flights
London City to San Diego flights
Southend to Los Angeles flights
Heathrow to Santa Rosa flights
Heathrow to Reno flights
Heathrow to San Luis Obispo flights
Gatwick to Ontario flights
London City to San Jose flights
Heathrow to Sacramento flights
Gatwick to Reno flights
Heathrow to Palm Springs flights
Gatwick to Sacramento flights
London City to Ontario flights
Stansted to San Diego flights
Stansted to Las Vegas flights
Heathrow to Santa Barbara flights
Gatwick to Long Beach flights
London City to Sacramento flights
Heathrow to Fresno flights
Heathrow to Monterey flights
Gatwick to Palm Springs flights
London City to Burbank flights
Southend to San Francisco flights

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 June 2025.
AirlineCheapestAverageFlexibilityOn-time
FinnairCheapest£366Average£437FlexibilityNo cancel feeOn-time76%
Search Finnair flights
KLMCheapest£378Average£578FlexibilityNo cancel feeOn-time75%
Search KLM flights
British AirwaysCheapest£385Average£507FlexibilityNo cancel feeOn-time70%
Search British Airways flights
United AirlinesCheapest£395Average£641FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
Virgin AtlanticCheapest£406Average£510FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights
LufthansaCheapest£431Average£554FlexibilityNo 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.

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.
Site
©2025 Cheapflights