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Ontario

$490+ Cheap flights from London (LON) to Ontario (ONT)

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 10/1. Fares are subject to change and may not be available on all flights or dates of travel.
LON — ONT
Aug 4 — Aug 111
Mon 8/4
Mon 8/11
1 adult, Economy
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Cheapflights Tip: The best prices from London to Ontario are usually found in February or January, booked 77 days in advance, depart on a Tuesday or Wednesday and return on a Wednesday

Cheap flight deals from London to Ontario

Discover tips and strategies to find the most affordable flight options for your journey from London (LON) 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 July 30, 2025.

Round-trip from

$542
(Netflights)

One-way from

$490
(Kiwi.com)

Popular in

July

Cheapest in

February

Average price

$1,164
From London (LON) to Ontario
Search Deals
One-way flight from London (LON) to Ontario
Search Deals
Highest demand for flights based on searches. 23% potential increase in price ($231 potential increase over avg. RT price).
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Cheapest flight prices on average. 5% potential price decrease ($39 potential savings vs. average RT price).
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Average for round-trip flights in July 2025
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Find flight deals from London to Ontario

Cheapest flights from London to Ontario
Explore the most affordable flight options available from London to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 30, 2025.

This Netflights deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Netflights is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/138:20 amLHR - ONT
1 stop22h 13mBritish Airways
Sat 9/2012:47 pmONT - LHR
1 stop15h 58mBritish Airways
Deal found 7/29$542
This American Airlines deal was found by Cheapflights users on 7/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/223:40 pmLHR - ONT
1 stop14h 08mAmerican Airlines
Sun 10/54:45 pmONT - LHR
1 stop12h 05mAmerican Airlines
Deal found 7/30$567
This Iberia deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Iberia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/137:35 amLHR - ONT
2 stops22h 58mIberia
Sat 9/2010:53 amONT - LHR
1 stop19h 32mIberia
Deal found 7/29$579
This World Air Fares deal was found by Cheapflights users on 7/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure World Air Fares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/73:40 pmLHR - ONT
1 stop14h 08mFinnair
Sun 9/1410:55 amONT - LHR
2 stops16h 10mFinnair
Deal found 7/28$585
This Iberia deal was found by Cheapflights users on 7/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Iberia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/2111:35 amLGW - ONT
2 stops20h 33mIberia
Mon 8/252:57 pmONT - LGW
2 stops21h 03mIberia
Deal found 7/30$681
This United Airlines deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/129:25 amLCY - ONT
2 stops19h 08mMultiple Airlines
Fri 9/196:00 amONT - LCY
2 stops21h 40mMultiple Airlines
Deal found 7/29$782
This Delta deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/129:20 amLCY - ONT
2 stops21h 03mDelta
Fri 9/1911:55 amONT - LCY
2 stops15h 45mDelta
Deal found 7/29$792
This Netflights deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Netflights is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/89:20 amLCY - ONT
2 stops21h 22mVirgin Atlantic
Tue 9/1611:55 amONT - LCY
2 stops20h 45mVirgin Atlantic
Deal found 7/29$813
This American Airlines deal was found by Cheapflights users on 7/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/213:05 pmLGW - ONT
2 stops34h 47mMultiple Airlines
Thu 9/186:10 amONT - LGW
2 stops18h 00mMultiple Airlines
Deal found 7/30$834
This Iberia deal was found by Cheapflights users on 7/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Iberia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/177:50 amLCY - ONT
2 stops22h 08mIberia
Wed 12/3111:00 amONT - LCY
2 stops19h 05mIberia
Deal found 7/30$1,087
This oojo deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/34:20 pmLCY - ONT
2 stops34h 33mBritish Airways
Sun 8/1011:59 pmONT - LCY
2 stops27h 56mBritish Airways
Deal found 7/29$1,165
This The Travel House deal was found by Cheapflights users on 7/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure The Travel House is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/3112:00 pmLGW - ONT
2 stops42h 27mKLM
Thu 8/77:05 amONT - LGW
2 stops18h 55mKLM
Deal found 7/30$1,716

Cheapflights Fare Finder

 
Customize your flight search to find flights from London 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 2,558,603 searches. Data last updated July 30, 2025.
Use the filters below to find and compare flights from London to Ontario that are best for you.

Fly from

London

Fly to

Ontario

Route

Depart

Return

Price

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 9/13

8:20 am-10:33 pm

1 stop22h 13m

Ontario

Sat 9/20

12:47 pm-12:45 pm

1 stop15h 58m

$542

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 9/22

3:40 pm-9:48 pm

1 stop14h 08m

Ontario

Sun 10/5

4:45 pm-12:50 pm

1 stop12h 05m

$567

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 9/13

7:35 am-10:33 pm

2 stops22h 58m

Ontario

Sat 9/20

10:53 am-2:25 pm

1 stop19h 32m

$579

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sun 9/7

3:40 pm-9:48 pm

1 stop14h 08m

Ontario

Sun 9/14

10:55 am-11:05 am

2 stops16h 10m

$585

LondonOntario

LGW - ONT

LGWONT

London Gatwick

Thu 8/21

11:35 am-12:08 am

2 stops20h 33m

Ontario

Mon 8/25

2:57 pm-8:00 pm

2 stops21h 03m

$681

LondonOntario

LCY - ONT

LCYONT

London City

Fri 9/12

9:25 am-8:33 pm

2 stops19h 08m

Ontario

Fri 9/19

6:00 am-11:40 am

2 stops21h 40m

$782

LondonOntario

LCY - ONT

LCYONT

London City

Fri 9/12

9:20 am-10:23 pm

2 stops21h 03m

Ontario

Fri 9/19

11:55 am-11:40 am

2 stops15h 45m

$792

LondonOntario

LCY - ONT

LCYONT

London City

Mon 9/8

9:20 am-10:42 pm

2 stops21h 22m

Ontario

Tue 9/16

11:55 am-4:40 pm

2 stops20h 45m

$813

LondonOntario

LGW - ONT

LGWONT

London Gatwick

Thu 8/21

3:05 pm-5:52 pm

2 stops34h 47m

Ontario

Thu 9/18

6:10 am-8:10 am

2 stops18h 00m

$834

LondonOntario

LCY - ONT

LCYONT

London City

Wed 12/17

7:50 am-9:58 pm

2 stops22h 08m

Ontario

Wed 12/31

11:00 am-2:05 pm

2 stops19h 05m

$1,087

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/29

Showing 1-10 of 25 results
1
2
3

Best time to book a flight from London to Ontario

Have a flexible travel schedule? Discover the best time to fly to Ontario from London with our price prediction graph.
Estimated round-trip 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 to Ontario

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

Use this chart to determine the optimal time to book a round-trip flight from London to Ontario. Price data was last updated on July 25, 2025.

Booking 77 days in advance of your planned departure date is, on average, the best time to get cheap flights from London to Ontario. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

What is the cheapest month to book a flight from London to Ontario?

Currently, August is the cheapest month in which you can book a flight from London to Ontario (average of $246). Flying from London to Ontario in March is currently the most expensive (average of $328). 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 LON to ONT?

Find hourly flight availability from London 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 July 30, 2025.

A simple way to save on the total cost of your ticket is to fly from London to Ontario in the afternoon. If you’re flexible enough to do this you can expect to save up to 27% on your trip compared to booking a flight at noon.

How much does it cost to fly round-trip from London 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 July 30, 2025.
Read reviews from past customers who have flown Delta, Finnair, and Virgin Atlantic from London 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
7,980 reviews

Comfort

7.9

Overall

8.0

Food

7.3

Entertainment

7.9

Boarding

8.2

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
7,980 reviews
Delta
8.0
Very good
7,980 reviews

Comfort

7.9

Overall

8.0

Food

7.3

Entertainment

7.9

Boarding

8.2

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
1,316 reviews
Delta
8.0
Very good
7,980 reviews

Comfort

7.9

Overall

8.0

Food

7.3

Entertainment

7.9

Boarding

8.2

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
655 reviews
Delta
8.0
Very good
7,980 reviews

Comfort

7.9

Overall

8.0

Food

7.3

Entertainment

7.9

Boarding

8.2

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
JetBlue
7.3
Good
2,913 reviews
Delta
8.0
Very good
7,980 reviews

Comfort

7.9

Overall

8.0

Food

7.3

Entertainment

7.9

Boarding

8.2

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
American Airlines
7.2
Good
10,000 reviews
Delta
8.0
Very good
7,980 reviews

Comfort

7.9

Overall

8.0

Food

7.3

Entertainment

7.9

Boarding

8.2

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 London 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?

    Ontario (ONT), located 3.1 mi from the city center, is the airport you fly into when you book flights from London to Ontario. 1 airline have flights to Ontario from London on a regular basis. Booking flights from London to Ontario should not be difficult; the airport handles an average of 0 inbound flights from London per day.

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

    Cheapflights users have booked flights from London to Ontario round-trip from $542. Other airlines that can offer you cheap pricing are American Airlines, from $567, and Iberia, from $579. These flights start at 26% lower than the current average price 3 months from now.

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

    For one-way options, check prices for Iberia. According to our data, you can fly for as low as $623. Users have also found prices from $624 and $684 on British Airways and WestJet, respectively.

  • What are the most popular routes from London to Ontario?

    Most travelers choose London Heathrow - Ontario, London Gatwick - Ontario or London City - Ontario when deciding on the best route from London to Ontario.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from London 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 to Ontario?

    Currently, August is the cheapest month in which you can book a flight from London to Ontario (average of $246). Flying from London to Ontario in March is currently the most expensive (average of $328). 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 London to Ontario

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Top airline flying from London to Ontario

Discover the top airline that operate flights from London 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 2,558,603 searches. Data last updated July 30, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$560Average$694FlexibilityNo cancel feeOn-time69%

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