Ontario

$375+ 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 5/1. Fares are subject to change and may not be available on all flights or dates of travel.
LON — ONT
Apr 2 — Apr 91
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Find cheap flights from London to Ontario with Cheapflights

1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”
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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 March 28, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$505
(World Air Fares)

One-way from

$375
(Kiwi.com)

Popular in

August

Cheapest in

February

Average price

$645
Provider with most accurate pricing for London (LON)-Ontario flight deals.
Provider most trusted by Cheapflights users for London (LON)-Ontario flights.
From London (LON) to Ontario
One-way flight from London (LON) to Ontario
Highest demand for flights based on searches. 17% potential increase in price ($149 potential increase over avg. RT price).
Cheapest flight prices on average. 5% potential price decrease ($37 potential savings vs. average RT price).
Average for round-trip flights in March 2025

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 March 28, 2025.

This World Air Fares deal was found by Cheapflights users on 3/26. 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.
Fri 5/212:20 pmLGW - ONT
2 stops19h 30mFinnair
Sun 5/410:40 pmONT - LGW
2 stops25h 30mFinnair
Deal found 3/26$505
This TravelUp deal was found by Cheapflights users on 3/26. 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 5/711:45 amLHR - ONT
2 stops19h 57mVirgin Atlantic
Sat 5/171:10 pmONT - LHR
2 stops16h 00mVirgin Atlantic
Deal found 3/26$519
This World Air Fares deal was found by Cheapflights users on 3/26. 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.
Fri 4/2512:20 pmLGW - ONT
2 stops19h 30mMultiple Airlines
Fri 5/211:59 pmONT - LGW
2 stops24h 11mMultiple Airlines
Deal found 3/26$523
This TravelUp deal was found by Cheapflights users on 3/27. 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.
Tue 5/66:30 amLHR - ONT
2 stops18h 14mKLM
Tue 5/1310:01 amONT - LHR
1 stop15h 49mKLM
Deal found 3/27$527
This American Airlines deal was found by Cheapflights users on 3/27. 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.
Fri 9/123:10 pmLHR - ONT
1 stop16h 26mAmerican Airlines
Mon 9/223:00 pmONT - LHR
1 stop13h 30mAmerican Airlines
Deal found 3/27$545
This British Airways deal was found by Cheapflights users on 3/27. 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.
Wed 4/234:25 pmLHR - ONT
1 stop15h 25mBritish Airways
Wed 4/306:00 amONT - LHR
1 stop16h 25mBritish Airways
Deal found 3/27$546
This Iberia deal was found by Cheapflights users on 3/27. 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 9/1110:50 amLHR - ONT
2 stops20h 46mIberia
Wed 9/1712:49 pmONT - LHR
1 stop14h 01mIberia
Deal found 3/27$548
This Delta deal was found by Cheapflights users on 3/26. 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 5/106:30 amLHR - ONT
2 stops19h 50mDelta
Sat 5/177:05 amONT - LHR
2 stops18h 55mDelta
Deal found 3/26$550
This Delta deal was found by Cheapflights users on 3/27. 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 5/1010:00 amLCY - ONT
2 stops20h 35mDelta
Wed 5/141:10 pmONT - LCY
2 stops19h 30mDelta
Deal found 3/27$591
This United Airlines deal was found by Cheapflights users on 3/27. 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.
Thu 9/119:30 amLHR - ONT
2 stops18h 47mUnited Airlines
Wed 9/176:36 pmONT - LHR
2 stops31h 04mUnited Airlines
Deal found 3/27$593
This Lufthansa deal was found by Cheapflights users on 3/26. 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 Lufthansa is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/1010:00 amLHR - ONT
1 stop20h 00mMultiple Airlines
Sat 5/176:00 amONT - LHR
1 stop20h 25mMultiple Airlines
Deal found 3/26$624
This World Air Fares deal was found by Cheapflights users on 3/27. 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.
Wed 11/511:45 amLHR - ONT
1 stop16h 26mFinnair
Thu 11/1311:00 amONT - LHR
1 stop13h 15mFinnair
Deal found 3/27$640

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 March 28, 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

Fri 5/2

12:20 pm-11:50 pm

2 stops19h 30m

Ontario

Sun 5/4

10:40 pm-8:10 am

2 stops25h 30m

$505

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 5/7

11:45 am-11:42 pm

2 stops19h 57m

Ontario

Sat 5/17

1:10 pm-1:10 pm

2 stops16h 00m

$519

LondonOntario

LGW - ONT

LGWONT

London Gatwick

Fri 4/25

12:20 pm-11:50 pm

2 stops19h 30m

Ontario

Fri 5/2

11:59 pm-8:10 am

2 stops24h 11m

$523

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Tue 5/6

6:30 am-4:44 pm

2 stops18h 14m

Ontario

Tue 5/13

10:01 am-9:50 am

1 stop15h 49m

$527

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Fri 9/12

3:10 pm-11:36 pm

1 stop16h 26m

Ontario

Mon 9/22

3:00 pm-12:30 pm

1 stop13h 30m

$545

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 4/23

4:25 pm-11:50 pm

1 stop15h 25m

Ontario

Wed 4/30

6:00 am-6:25 am

1 stop16h 25m

$546

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Thu 9/11

10:50 am-11:36 pm

2 stops20h 46m

Ontario

Wed 9/17

12:49 pm-10:50 am

1 stop14h 01m

$548

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 5/10

6:30 am-6:20 pm

2 stops19h 50m

Ontario

Sat 5/17

7:05 am-10:00 am

2 stops18h 55m

$550

LondonOntario

LCY - ONT

LCYONT

London City

Sat 5/10

10:00 am-10:35 pm

2 stops20h 35m

Ontario

Wed 5/14

1:10 pm-4:40 pm

2 stops19h 30m

$591

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Thu 9/11

9:30 am-8:17 pm

2 stops18h 47m

Ontario

Wed 9/17

6:36 pm-9:40 am

2 stops31h 04m

$593

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/26

Showing 1-10 of 44 results
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Compare providers for flights from London to Ontario

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from London to Ontario in March.
ProviderPrice AccuracyTrust Score*
FlightHubPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • 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 March 21, 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 $326). 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 March 28, 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.

Rainfall in Ontario by month

Plan your trip to Ontario by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Ontario ranges from 0.1 - 3.4 inches per month. February is typically the wettest month, when rainfall can reach 3.4 in. June is typically the driest time to visit Ontario when rainfall is around 0.1 in.

Temperature in Ontario by month

Plan your trip to Ontario by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Ontario, use this chart to help with planning. For those seeking warmer temperatures, August is the ideal time of year to visit, when temperatures reach an average of 78.8 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 53.6 F).

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 March 28, 2025.
Peruse reviews from past customers who have flown with Delta, KLM and Finnair from London to Ontario to help guide your decision. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
8.0
Very good

Overall

8.0

Food

7.3

Boarding

8.2

Comfort

8.0

Entertainment

7.9

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
8.0
Very good
8.0
Very good

Overall

8.0

Food

7.3

Boarding

8.2

Comfort

8.0

Entertainment

7.9

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
8.0
Very good

Overall

8.0

Food

7.3

Boarding

8.2

Comfort

8.0

Entertainment

7.9

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
8.0
Very good

Overall

8.0

Food

7.3

Boarding

8.2

Comfort

8.0

Entertainment

7.9

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
8.0
Very good

Overall

8.0

Food

7.3

Boarding

8.2

Comfort

8.0

Entertainment

7.9

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
8.0
Very good

Overall

8.0

Food

7.3

Boarding

8.2

Comfort

8.0

Entertainment

7.9

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 $505. Other airlines that can offer you cheap pricing are Virgin Atlantic, from $519, and KLM, from $527. These flights start at 30% 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 Lufthansa. According to our data, you can fly for as low as $520. Users have also found prices from $682 and $698 on WestJet and Air France, respectively.

  • What are the most popular routes 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 $326). 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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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 March 28, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$662Average$836FlexibilityNo cancel feeOn-time69%
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