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$397+ 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 1/11. Fares are subject to change and may not be available on all flights or dates of travel.
LON — ONT
ene. 14 — ene. 211
mié. 1/14
mié. 1/21
1 adult, Economy
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Cheapflights Tip: The best prices from London to Ontario are usually found in January or September, booked 81 days in advance, depart on a Tuesday or Wednesday and return on a Wednesday

Cheap 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 diciembre 15, 2025.

This Netflights deal was found by Cheapflights users on 12/15. 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.
mié. 12/2410:45 amLHR - ONT
1 stop19h 48mVirgin Atlantic
sáb. 1/3112:41 pmONT - LHR
1 stop14h 59mVirgin Atlantic
Deal found 12/15$678
This Delta deal was found by Cheapflights users on 12/13. 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.
mié. 12/246:30 amLHR - ONT
2 stops21h 20mDelta
sáb. 1/246:00 amONT - LHR
1 stop20h 00mDelta
Deal found 12/13$691
This Delta deal was found by Cheapflights users on 12/12. 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.
mié. 12/2411:45 amLHR - ONT
2 stops30h 15mDelta
mié. 1/73:30 pmONT - LHR
1 stop35h 00mDelta
Deal found 12/12$694
This Delta deal was found by Cheapflights users on 12/13. 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.
lun. 12/158:40 amLHR - ONT
2 stops22h 24mDelta
sáb. 1/101:11 pmONT - LHR
1 stop12h 49mDelta
Deal found 12/13$695
This Delta deal was found by Cheapflights users on 12/13. 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.
mié. 12/2410:45 amLHR - ONT
1 stop19h 48mDelta
mar. 1/1312:41 pmONT - LHR
1 stop14h 59mDelta
Deal found 12/13$709
This Delta deal was found by Cheapflights users on 12/12. 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.
sáb. 12/273:05 pmLHR - ONT
1 stop27h 57mDelta
mié. 1/75:07 pmONT - LHR
2 stops19h 03mDelta
Deal found 12/12$711
This Delta deal was found by Cheapflights users on 12/12. 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.
dom. 12/2110:45 amLHR - ONT
1 stop13h 27mDelta
mar. 1/610:30 pmONT - LHR
2 stops28h 20mDelta
Deal found 12/12$712
This Virgin Atlantic deal was found by Cheapflights users on 12/13. 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 Virgin Atlantic is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 12/1512:20 pmLHR - ONT
1 stop18h 27mVirgin Atlantic
sáb. 1/107:30 amONT - LHR
1 stop20h 25mVirgin Atlantic
Deal found 12/13$713
This Trip.com deal was found by Cheapflights users on 12/15. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 12/162:45 pmLHR - ONT
1 stop16h 02mVirgin Atlantic
lun. 12/226:00 amONT - LHR
1 stop20h 00mVirgin Atlantic
Deal found 12/15$721
This Delta deal was found by Cheapflights users on 12/13. 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.
mié. 12/246:30 amLHR - ONT
2 stops21h 20mDelta
mié. 12/317:05 amONT - LHR
1 stop15h 20mDelta
Deal found 12/13$722
This Trip.com deal was found by Cheapflights users on 12/14. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 12/1512:20 pmLHR - ONT
1 stop18h 27mVirgin Atlantic
lun. 12/226:00 amONT - LHR
1 stop20h 00mVirgin Atlantic
Deal found 12/14$725
This Delta deal was found by Cheapflights users on 12/13. 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.
dom. 12/211:45 pmLCY - ONT
2 stops28h 15mDelta
mar. 12/307:05 amONT - LCY
2 stops16h 10mDelta
Deal found 12/13$917

Find 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 diciembre 15, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
1 star

Round-trip from

$611
(flygcity.se)

One-way from

$397
(Kiwi.com)

Popular in

July

Cheapest in

January

Average price

$741
Provider with most accurate pricing for London (LON)-Ontario flight deals.
Search Deals
Provider most trusted by Cheapflights users for London (LON)-Ontario flights.
Search Deals
From London (LON) to Ontario
Search Deals
One-way flight from London (LON) to Ontario
Search Deals
Highest demand for flights based on searches. 21% potential increase in price ($198 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 6% potential price decrease ($42 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in December 2025
Search Deals

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 diciembre 15, 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

mar. 1/13

7:30 am-8:58 pm

2 stops21h 28m

Ontario

mar. 1/20

5:05 am-5:55 am

2 stops16h 50m

$636

LondonOntario

LGW - ONT

LGWONT

London Gatwick

lun. 3/2

7:40 pm-4:24 pm

2 stops28h 44m

Ontario

lun. 3/16

10:56 am-7:00 pm

2 stops25h 04m

$637

LondonOntario

LGW - ONT

LGWONT

London Gatwick

lun. 1/26

12:30 pm-2:18 pm

2 stops33h 48m

Ontario

mar. 2/10

6:00 am-7:30 am

2 stops17h 30m

$651

LondonOntario

LHR - ONT

LHRONT

London Heathrow

dom. 1/11

10:45 am-10:38 pm

1 stop19h 53m

Ontario

dom. 1/18

12:41 pm-7:50 am

1 stop35h 09m

$662

LondonOntario

LHR - ONT

LHRONT

London Heathrow

sáb. 3/28

4:10 pm-11:35 am

2 stops26h 25m

Ontario

sáb. 4/11

1:20 pm-1:10 pm

2 stops15h 50m

$665

LondonOntario

LHR - ONT

LHRONT

London Heathrow

mié. 1/14

10:05 am-5:43 pm

1 stop15h 38m

Ontario

mié. 2/4

1:24 pm-9:40 am

1 stop12h 16m

$667

LondonOntario

LHR - ONT

LHRONT

London Heathrow

mar. 1/20

1:45 pm-10:53 pm

1 stop17h 08m

Ontario

mié. 9/23

1:00 pm-9:40 am

1 stop12h 40m

$667

LondonOntario

LHR - ONT

LHRONT

London Heathrow

mar. 1/20

11:35 am-8:58 pm

1 stop17h 23m

Ontario

mar. 10/6

1:33 pm-11:10 am

1 stop13h 37m

$667

LondonOntario

LHR - ONT

LHRONT

London Heathrow

mié. 3/18

1:45 pm-10:57 pm

1 stop16h 12m

Ontario

lun. 3/23

1:50 pm-9:40 am

1 stop12h 50m

$667

LondonOntario

LHR - ONT

LHRONT

London Heathrow

lun. 2/2

10:05 am-5:43 pm

1 stop15h 38m

Ontario

lun. 2/16

1:50 pm-12:00 pm

1 stop14h 10m

$667

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/14

Showing 1-10 of 60 results
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  • Most accurate provider: When it comes to deals on London-Ontario flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on London-Ontario flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from London-Ontario flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on London-Ontario flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for London-Ontario flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

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 December 12, 2025.

Booking 81 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, September is the cheapest month in which you can book a flight from London to Ontario (average of $320). Flying from London to Ontario in July is currently the most expensive (average of $539). 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 diciembre 15, 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 22% on your trip compared to booking a flight at noon.

How much does it cost to fly round-trip from London to Ontario?

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 United Airlines, British Airways, and American Airlines fly from London to Ontario in about 21h 28m. The time it takes to get you to your destination can typically vary by up to 12h 20m. London and Ontario are separated by a distance of 5407 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 21% lower than the current average price 3 months from now.

  • 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, September is the cheapest month in which you can book a flight from London to Ontario (average of $320). Flying from London to Ontario in July is currently the most expensive (average of $539). 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 diciembre 15, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$560Average$694FlexibilityNo cancel feeOn-time69%

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