Find flights
When to book
Airlines
FAQs

Cheap flights from London Heathrow Airport to Ontario from £406

This is the cheapest retur flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 11/11. Fares are subject to change and may not be available on all flights or dates of travel.
LHR — ONT
6 Jul — 13 Jul1
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 1 July 2025.

Round-trip from

£406

Popular in

August

Cheapest in

February

Average price

£574
British Airways
  • British Airways
  • 11/11-18/11
  • 2 total stops
  • 27h 24m 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 July 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 1 July 2025.

Tue 11/1114:55LHR - ONT
1 stop15h 05mBritish Airways
Tue 18/1117:01ONT - LHR
1 stop12h 19mBritish Airways
Deal found 30/6£406
Sun 24/812:00LHR - ONT
1 stop14h 25mAmerican Airlines
Tue 9/916:45ONT - LHR
1 stop12h 05mAmerican Airlines
Deal found 1/7£427
Thu 30/1012:20LHR - ONT
1 stop17h 22mVirgin Atlantic
Mon 3/1117:51ONT - LHR
1 stop13h 54mVirgin Atlantic
Deal found 29/6£427
Thu 13/1106:30LHR - ONT
2 stops18h 47mDelta
Sun 16/1122:59ONT - LHR
1 stop24h 51mDelta
Deal found 30/6£429
Mon 3/1116:30LHR - ONT
1 stop15h 15mIberia
Sun 16/1112:53ONT - LHR
1 stop13h 07mIberia
Deal found 30/6£443
Sat 15/1106:20LHR - ONT
2 stops21h 22mMultiple Airlines
Sun 16/1122:59ONT - LHR
1 stop23h 26mMultiple Airlines
Deal found 30/6£446
Sat 20/911:20LHR - ONT
1 stop15h 55mKLM
Fri 3/1013:15ONT - LHR
1 stop12h 35mKLM
Deal found 29/6£453
Fri 5/915:10LHR - ONT
1 stop15h 23mFinnair
Fri 12/914:54ONT - LHR
1 stop13h 51mFinnair
Deal found 30/6£455
Mon 17/1110:05LHR - ONT
1 stop15h 29mUnited Airlines
Thu 27/1113:00ONT - LHR
1 stop12h 40mUnited Airlines
Deal found 30/6£492
Thu 28/812:00LHR - ONT
1 stop14h 25mRoyal Air Maroc
Fri 5/914:54ONT - LHR
1 stop15h 31mRoyal Air Maroc
Deal found 1/7£496
Wed 19/1115:00LHR - ONT
2 stops39h 45mAir Canada
Tue 2/1205:10ONT - LHR
2 stops17h 20mAir Canada
Deal found 30/6£505

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 1 July 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 11/11

14:55-22:00

1 stop15h 05m

Ontario

Tue 18/11

17:01-13:20

1 stop12h 19m

£406

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sun 24/8

12:00-18:25

1 stop14h 25m

Ontario

Tue 9/9

16:45-12:50

1 stop12h 05m

£427

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Thu 30/10

12:20-22:42

1 stop17h 22m

Ontario

Mon 3/11

17:51-15:45

1 stop13h 54m

£427

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Thu 13/11

06:30-17:17

2 stops18h 47m

Ontario

Sun 16/11

22:59-07:50

1 stop24h 51m

£429

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 3/11

16:30-23:45

1 stop15h 15m

Ontario

Sun 16/11

12:53-10:00

1 stop13h 07m

£443

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 15/11

06:20-19:42

2 stops21h 22m

Ontario

Sun 16/11

22:59-06:25

1 stop23h 26m

£446

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 20/9

11:20-19:15

1 stop15h 55m

Ontario

Fri 3/10

13:15-09:50

1 stop12h 35m

£453

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Fri 5/9

15:10-22:33

1 stop15h 23m

Ontario

Fri 12/9

14:54-12:45

1 stop13h 51m

£455

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 17/11

10:05-17:34

1 stop15h 29m

Ontario

Thu 27/11

13:00-09:40

1 stop12h 40m

£492

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Thu 28/8

12:00-18:25

1 stop14h 25m

Ontario

Fri 5/9

14:54-14:25

1 stop15h 31m

£496

Flights are sorted by cheapest return flights first.

Deals found on 30/6

Showing 1-10 of 18 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 27 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 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 1 July 2025.

It’s optimal to fly from London Heathrow Airport to Ontario in the afternoon. By choosing this option you can save up to 24% on the cost of your flight, compared to a flight at midday.

How much does it cost for a return flight from London Heathrow Airport to Ontario?

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 1 July 2025.
Read reviews from past customers who have flown with Delta, KLM, andFinnair 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.
Delta
8.0
Very Good
7,973 reviews
Check prices

Boarding

8.2

Entertainment

7.9

Overall

8.0

Comfort

7.9

Food

7.3

Crew

8.5

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
7,973 reviews
Delta
8.0
Very Good
7,973 reviews
Check prices

Boarding

8.2

Entertainment

7.9

Overall

8.0

Comfort

7.9

Food

7.3

Crew

8.5

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
1,366 reviews
Delta
8.0
Very Good
7,973 reviews
Check prices

Boarding

8.2

Entertainment

7.9

Overall

8.0

Comfort

7.9

Food

7.3

Crew

8.5

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
1,301 reviews
Delta
8.0
Very Good
7,973 reviews
Check prices

Boarding

8.2

Entertainment

7.9

Overall

8.0

Comfort

7.9

Food

7.3

Crew

8.5

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
8,852 reviews
Delta
8.0
Very Good
7,973 reviews
Check prices

Boarding

8.2

Entertainment

7.9

Overall

8.0

Comfort

7.9

Food

7.3

Crew

8.5

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
654 reviews
Delta
8.0
Very Good
7,973 reviews
Check prices

Boarding

8.2

Entertainment

7.9

Overall

8.0

Comfort

7.9

Food

7.3

Crew

8.5

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 £406, 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 American Airlines and Virgin Atlantic - these airlines can fly you to your destination from £427 and £427, respectively. Users have found that British Airways is 23% 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 British Airways, which is currently one of the cheapest options available, starting at £475. Iberia flights start at £488 while deals on JetBlue start at £586 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
Heathrow to Las Vegas flights
London City to Los Angeles flights
Gatwick to Los Angeles flights
London City to San Francisco flights
Gatwick to San Francisco flights
Gatwick to Las Vegas flights
London City to Las Vegas flights
Luton to Los Angeles flights
Heathrow to Santa Ana flights
Luton to San Francisco flights
Stansted to Los Angeles flights
Heathrow to Long Beach flights
Heathrow to San Diego flights
Stansted to San Francisco flights
Heathrow to Burbank flights
Heathrow to Oakland flights
Heathrow to San Jose flights
Gatwick to San Jose flights
Luton to Las Vegas flights
Southend to Los Angeles flights
Gatwick to Santa Ana flights
Gatwick to Burbank flights
Gatwick to Oakland flights
Gatwick to San Diego flights
London City to Santa Ana flights
Stansted to Las Vegas flights
London City to San Diego flights
Gatwick to Ontario flights
Heathrow to Reno flights
Heathrow to Santa Rosa flights
Heathrow to Sacramento flights
Gatwick to Reno flights
Heathrow to Palm Springs flights
London City to Ontario flights
London City to Oakland flights
Stansted to San Diego flights
Heathrow to Fresno flights
London City to San Jose flights
Heathrow to San Luis Obispo flights
Gatwick to Sacramento flights
London City to Sacramento flights
London City to Burbank flights
Southend to Las Vegas flights
London City to Palm Springs flights
Southend to San Francisco flights
Gatwick to Palm Springs flights
Luton to Oakland 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 1 July 2025.
AirlineCheapestAverageFlexibilityOn-time
FinnairCheapest£351Average£428FlexibilityNo cancel feeOn-time76%
Search Finnair flights
British AirwaysCheapest£370Average£476FlexibilityNo cancel feeOn-time70%
Search British Airways flights
KLMCheapest£371Average£583FlexibilityNo cancel feeOn-time75%
Search KLM flights
United AirlinesCheapest£387Average£577FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
Virgin AtlanticCheapest£398Average£500FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights
LufthansaCheapest£422Average£543FlexibilityNo 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