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Ontario

$332+ 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 3/2. Fares are subject to change and may not be available on all flights or dates of travel.
LON — ONT
Mar 3 — Mar 101
Tue 3/3
Tue 3/10
1 adult, Economy
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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 February 1, 2026.

This TravelUp deal was found by Cheapflights users on 1/30. 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 TravelUp is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/28:25 pm
LHR
-
ONT
2 stops34h 12m
Virgin Atlantic
Mon 3/911:59 am
ONT
-
LHR
1 stop16h 56m
Virgin Atlantic
Deal found 1/30$478
This TravelUp deal was found by Cheapflights users on 1/31. 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.
Wed 3/1811:05 am
LHR
-
ONT
2 stops19h 46m
Virgin Atlantic
Wed 3/2511:59 am
ONT
-
LHR
1 stop15h 31m
Virgin Atlantic
Deal found 1/31$490
This TravelUp deal was found by Cheapflights users on 1/30. 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 TravelUp is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 2/710:45 am
LHR
-
ONT
1 stop19h 03m
Virgin Atlantic
Sat 2/141:15 pm
ONT
-
LHR
1 stop14h 25m
Virgin Atlantic
Deal found 1/30$494
This United Airlines deal was found by Cheapflights users on 1/30. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/169:30 am
LHR
-
ONT
2 stops20h 27m
United Airlines
Mon 3/236:37 pm
ONT
-
LHR
2 stops18h 58m
United Airlines
Deal found 1/30$500
This Delta deal was found by Cheapflights users on 1/31. 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.
Wed 3/186:30 am
LHR
-
ONT
2 stops17h 43m
Delta
Wed 3/256:00 am
ONT
-
LHR
2 stops17h 25m
Delta
Deal found 1/31$504
This Delta deal was found by Cheapflights users on 1/31. 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.
Mon 2/96:30 am
LHR
-
ONT
2 stops22h 35m
Delta
Mon 2/235:00 pm
ONT
-
LHR
2 stops19h 10m
Delta
Deal found 1/31$506
This United Airlines deal was found by Cheapflights users on 1/31. 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.
Mon 4/279:30 am
LHR
-
ONT
2 stops20h 20m
United Airlines
Sat 5/96:00 am
ONT
-
LHR
1 stop17h 40m
United Airlines
Deal found 1/31$513
This Delta deal was found by Cheapflights users on 1/30. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 2/76:30 am
LHR
-
ONT
2 stops22h 35m
Delta
Sat 2/1410:20 pm
ONT
-
LHR
1 stop24h 05m
Delta
Deal found 1/30$514
This United Airlines deal was found by Cheapflights users on 1/31. 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.
Mon 2/99:30 am
LHR
-
ONT
2 stops20h 28m
United Airlines
Mon 2/236:37 pm
ONT
-
LHR
1 stop28h 48m
United Airlines
Deal found 1/31$517
This SmartFares deal was found by Cheapflights users on 1/31. 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 SmartFares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/710:55 am
LHR
-
ONT
1 stop13h 33m
Virgin Atlantic
Wed 4/221:29 pm
ONT
-
LHR
1 stop12h 31m
Virgin Atlantic
Deal found 1/31$520
This Delta deal was found by Cheapflights users on 1/31. 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.
Mon 4/2710:25 am
LGW
-
ONT
2 stops20h 12m
Delta
Sat 5/91:35 pm
ONT
-
LGW
2 stops18h 25m
Delta
Deal found 1/31$542
This Delta deal was found by Cheapflights users on 1/31. 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.
Mon 2/98:40 am
LCY
-
ONT
2 stops20h 25m
Delta
Mon 2/231:15 pm
ONT
-
LCY
2 stops19h 20m
Delta
Deal found 1/31$552

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 February 1, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$478
(TravelUp)

One-way from

$332
(Trip.com)

Popular in

July

Cheapest in

January

Average price

$558
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. 17% potential increase in price ($150 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease ($31 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in February 2026
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 February 1, 2026.
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

Wed 3/18

10:45 am-11:51 pm

1 stop20h 06m

Ontario

Wed 3/25

1:20 pm-10:00 am

1 stop13h 40m

$490

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 3/2

2:30 pm-10:37 pm

1 stop16h 07m

Ontario

Mon 3/23

12:50 pm-9:00 am

1 stop13h 10m

$521

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Tue 3/17

11:20 am-11:51 pm

2 stops19h 31m

Ontario

Tue 3/24

1:20 pm-11:55 am

2 stops15h 35m

$523

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 3/14

3:05 pm-10:33 pm

1 stop14h 28m

Ontario

Mon 3/16

12:57 pm-9:00 am

1 stop13h 03m

$524

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Tue 3/17

2:30 pm-10:34 pm

1 stop15h 04m

Ontario

Tue 3/24

12:57 pm-9:00 am

1 stop13h 03m

$526

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 3/14

3:05 pm-10:33 pm

1 stop14h 28m

Ontario

Mon 3/23

12:50 pm-9:00 am

1 stop13h 10m

$526

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 3/16

2:30 pm-10:34 pm

1 stop15h 04m

Ontario

Mon 3/23

12:50 pm-9:00 am

1 stop13h 10m

$526

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Fri 2/20

1:45 pm-8:07 pm

1 stop14h 22m

Ontario

Thu 2/26

1:40 pm-12:00 pm

1 stop14h 20m

$527

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 3/4

10:05 am-5:41 pm

1 stop15h 36m

Ontario

Sat 3/7

1:40 pm-12:00 pm

1 stop14h 20m

$529

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 2/21

10:05 am-5:41 pm

1 stop15h 36m

Ontario

Sat 2/28

1:53 pm-12:00 pm

1 stop14h 07m

$529

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/31

Showing 1-10 of 60 results
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2
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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 January 30, 2026.

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 $526). 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.

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 Virgin Atlantic, Delta, and Iberia fly from London to Ontario in about 20h 06m. The time it takes to get you to your destination can typically vary by up to 15h 13m. 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 $497. This flight start at 29% 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 $526). 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

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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 February 1, 2026.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$497Average$694FlexibilityNo cancel feeOn-time69%

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