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Ontario

$384+ 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 10/7. Fares are subject to change and may not be available on all flights or dates of travel.
LON — ONT
oct. 11 — oct. 181
sáb. 10/11
sáb. 10/18
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 septiembre 11, 2025.

Round-trip from

$489
(American Airlines)

One-way from

$384
(Kiwi.com)

Popular in

July

Cheapest in

February

Average price

$568
From London (LON) to Ontario
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One-way flight from London (LON) to Ontario
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Highest demand for flights based on searches. 22% potential increase in price ($212 potential increase over avg. RT price).
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Cheapest flight prices on average. 6% potential price decrease ($45 potential savings vs. average RT price).
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Average for round-trip flights in September 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 septiembre 11, 2025.

This TravelUp deal was found by Cheapflights users on 9/9. 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 TravelUp is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 10/77:15 pmLHR - ONT
2 stops35h 26mVirgin Atlantic
mar. 10/147:05 amONT - LHR
1 stop15h 40mVirgin Atlantic
Deal found 9/9$492
This TravelUp deal was found by Cheapflights users on 9/10. 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 TravelUp is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 11/37:50 pmLHR - ONT
2 stops57h 30mVirgin Atlantic
lun. 11/2411:45 amONT - LHR
1 stop13h 15mVirgin Atlantic
Deal found 9/10$509
This Netflights deal was found by Cheapflights users on 9/10. 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.
sáb. 9/278:20 amLHR - ONT
1 stop22h 13mBritish Airways
lun. 10/62:51 pmONT - LHR
1 stop15h 34mBritish Airways
Deal found 9/10$510
This TravelUp deal was found by Cheapflights users on 9/10. 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 TravelUp is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 11/38:20 amLHR - ONT
1 stop18h 01mBritish Airways
lun. 11/243:19 pmONT - LHR
1 stop12h 56mBritish Airways
Deal found 9/10$512
This British Airways deal was found by Cheapflights users on 9/9. 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 British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 11/57:35 amLHR - ONT
2 stops22h 54mBritish Airways
sáb. 11/224:47 pmONT - LHR
1 stop12h 28mBritish Airways
Deal found 9/9$522
This American Airlines deal was found by Cheapflights users on 9/11. 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.
vie. 9/2612:20 pmLGW - ONT
2 stops33h 34mAmerican Airlines
vie. 10/107:27 pmONT - LGW
2 stops28h 43mAmerican Airlines
Deal found 9/11$523
This Netflights deal was found by Cheapflights users on 9/10. 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.
dom. 9/2110:55 amLHR - ONT
1 stop20h 47mVirgin Atlantic
lun. 10/61:15 pmONT - LHR
1 stop12h 35mVirgin Atlantic
Deal found 9/10$529
This British Airways deal was found by Cheapflights users on 9/9. 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 British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 9/2312:00 pmLHR - ONT
1 stop14h 54mBritish Airways
mar. 9/3010:53 amONT - LHR
1 stop15h 57mBritish Airways
Deal found 9/9$530
This American Airlines deal was found by Cheapflights users on 9/10. 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.
vie. 9/1911:15 amLHR - ONT
1 stop15h 01mAmerican Airlines
mar. 10/74:49 pmONT - LHR
1 stop13h 51mAmerican Airlines
Deal found 9/10$532
This TravelUp deal was found by Cheapflights users on 9/10. 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 TravelUp is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 9/171:05 pmLHR - ONT
1 stop17h 18mKLM
lun. 9/221:15 pmONT - LHR
1 stop12h 35mKLM
Deal found 9/10$534
This Delta deal was found by Cheapflights users on 9/10. 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.
jue. 9/189:55 amLHR - ONT
2 stops20h 28mDelta
mié. 10/16:00 amONT - LHR
1 stop19h 50mDelta
Deal found 9/10$537
This Justfly.com deal was found by Cheapflights users on 9/11. 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 Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 10/63:10 pmLHR - ONT
1 stop15h 08mBritish Airways
lun. 10/1312:48 pmONT - LHR
1 stop14h 02mBritish Airways
Deal found 9/11$539

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 septiembre 11, 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

LGW - ONT

LGWONT

London Gatwick

jue. 2/26

12:30 pm-8:24 pm

2 stops39h 54m

Ontario

lun. 3/2

6:47 am-7:30 am

2 stops16h 43m

$489

LondonOntario

LHR - ONT

LHRONT

London Heathrow

mié. 11/5

7:35 am-10:29 pm

2 stops22h 54m

Ontario

sáb. 11/22

4:47 pm-1:15 pm

1 stop12h 28m

$522

LondonOntario

LGW - ONT

LGWONT

London Gatwick

vie. 9/26

12:20 pm-1:54 pm

2 stops33h 34m

Ontario

vie. 10/10

7:27 pm-8:10 am

2 stops28h 43m

$523

LondonOntario

LHR - ONT

LHRONT

London Heathrow

mié. 11/5

10:05 am-6:21 pm

1 stop16h 16m

Ontario

sáb. 11/22

4:47 pm-1:15 pm

1 stop12h 28m

$530

LondonOntario

LHR - ONT

LHRONT

London Heathrow

mar. 9/23

12:00 pm-6:54 pm

1 stop14h 54m

Ontario

mar. 9/30

10:53 am-10:50 am

1 stop15h 57m

$530

LondonOntario

LHR - ONT

LHRONT

London Heathrow

dom. 2/8

10:35 am-5:53 pm

1 stop15h 18m

Ontario

sáb. 2/14

11:05 am-8:15 am

1 stop13h 10m

$531

LondonOntario

LHR - ONT

LHRONT

London Heathrow

lun. 2/9

3:00 pm-10:02 pm

1 stop15h 02m

Ontario

sáb. 2/14

3:05 pm-12:15 pm

1 stop13h 10m

$531

LondonOntario

LHR - ONT

LHRONT

London Heathrow

vie. 9/26

12:00 pm-6:54 pm

1 stop14h 54m

Ontario

mié. 10/8

2:51 pm-2:25 pm

1 stop15h 34m

$531

LondonOntario

LHR - ONT

LHRONT

London Heathrow

lun. 9/22

12:00 pm-6:54 pm

1 stop14h 54m

Ontario

lun. 9/29

4:45 pm-2:40 pm

1 stop13h 55m

$532

LondonOntario

LHR - ONT

LHRONT

London Heathrow

mié. 9/24

12:00 pm-6:54 pm

1 stop14h 54m

Ontario

lun. 9/29

4:45 pm-2:40 pm

1 stop13h 55m

$532

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/11

Showing 1-10 of 59 results
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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 August 29, 2025.

Booking 76 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 septiembre 11, 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.

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.

  • How long is the flight from London to Ontario?

    Airlines like American Airlines, British Airways, and Delta fly from London to Ontario in about 22h. The time it takes to get you to your destination can typically vary by up to 17h 54m. London and Ontario are separated by a distance of 5422 mi. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

  • What is the cheapest airline to fly from London to Ontario round-trip?

    Cheapflights users have booked flights from London to Ontario round-trip from $560. This flight start at 23% 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 $441. Users have also found prices from $452 and $458 on British Airways and Delta, 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 septiembre 11, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$560Average$739FlexibilityNo cancel feeOn-time69%

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