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Cheap flights from London to Ontario from £316

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 13/5. Fares are subject to change and may not be available on all flights or dates of travel.
LON — ONT
24 Feb — 3 Mar1
1 adult
1 adult, Economy, 0 bags

Cheap flight deals from London to Ontario

Enter your travel dates to find the best prices.

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 25 January 2026.

Fri 20/208:30
LHR
-
ONT
2 stops22h 27m
United Airlines
Fri 27/218:37
ONT
-
LHR
2 stops17h 58m
United Airlines
Deal found 22/1£341
Mon 9/307:30
LHR
-
ONT
2 stops20h 20m
United Airlines
Mon 16/318:37
ONT
-
LHR
2 stops19h 43m
United Airlines
Deal found 23/1£341
Tue 10/308:30
LHR
-
ONT
2 stops20h 48m
United Airlines
Tue 17/306:15
ONT
-
LHR
1 stop18h 10m
United Airlines
Deal found 24/1£344
Tue 3/211:05
LHR
-
ONT
2 stops20h 53m
Virgin Atlantic
Thu 12/206:00
ONT
-
LHR
2 stops17h 05m
Virgin Atlantic
Deal found 22/1£352
Mon 27/409:30
LHR
-
ONT
2 stops20h 20m
United Airlines
Sat 9/506:00
ONT
-
LHR
2 stops43h 40m
United Airlines
Deal found 23/1£353
Mon 2/208:30
LHR
-
ONT
2 stops21h 28m
United Airlines
Thu 12/213:50
ONT
-
LHR
2 stops35h 50m
United Airlines
Deal found 22/1£355
Tue 10/310:45
LHR
-
ONT
1 stop20h 06m
Virgin Atlantic
Tue 17/312:57
ONT
-
LHR
1 stop34h 28m
Virgin Atlantic
Deal found 24/1£357
Tue 3/211:20
LGW
-
ONT
2 stops30h 48m
American Airlines
Thu 12/207:00
ONT
-
LGW
2 stops18h 00m
American Airlines
Deal found 22/1£363
Fri 20/210:05
LHR
-
ONT
1 stop15h 36m
United Airlines
Mon 23/213:50
ONT
-
LHR
1 stop14h 10m
United Airlines
Deal found 23/1£364
Thu 12/311:35
LHR
-
ONT
1 stop16h 15m
United Airlines
Sun 15/313:50
ONT
-
LHR
1 stop12h 50m
United Airlines
Deal found 24/1£366
Thu 19/310:05
LHR
-
ONT
1 stop14h 36m
United Airlines
Mon 23/313:40
ONT
-
LHR
1 stop15h 20m
United Airlines
Deal found 24/1£366
Mon 9/307:45
LCY
-
ONT
2 stops20h 15m
Delta
Mon 16/313:20
ONT
-
LCY
2 stops20h 15m
Delta
Deal found 23/1£408

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 25 January 2026.

Round-trip from

£341

One-way from

£316

Popular in

July

Cheapest in

January

Average price

£400
United Airlines
  • United Airlines
  • 20/2-27/2
  • 3 total stops
  • 44h 17m total
  • London to Ontario
Search Deals
British Airways
  • British Airways
  • 13/5
  • 2 total stops
  • 20h 16m total
  • London to Ontario
Search Deals
Highest demand for flights based on searches. 17% potential increase in price (£80 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease (£17 potential savings vs. average return price).
Search Deals
Average for round-trip flights in January 2026
Search Deals

Cheapflights Fare Finder

 
Customise 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 858,174 searches. Data last updated 25 January 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

Fri 20/2

08:30-22:57

2 stops22h 27m

Ontario

Fri 27/2

18:37-20:35

2 stops17h 58m

£341

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Tue 3/2

11:35-20:58

1 stop17h 23m

Ontario

Thu 12/2

13:50-12:00

1 stop14h 10m

£363

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 2/3

13:45-19:54

1 stop14h 09m

Ontario

Mon 9/3

13:40-12:00

1 stop15h 20m

£364

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Fri 20/2

10:05-17:41

1 stop15h 36m

Ontario

Fri 6/3

13:40-12:00

1 stop14h 20m

£364

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Fri 6/2

12:05-21:58

1 stop17h 53m

Ontario

Tue 10/2

13:24-09:40

1 stop12h 16m

£364

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 23/2

13:45-19:54

1 stop14h 09m

Ontario

Mon 2/3

13:50-12:00

1 stop14h 10m

£366

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 21/2

10:05-17:41

1 stop15h 36m

Ontario

Tue 3/3

13:50-12:00

1 stop14h 10m

£366

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 21/2

10:05-17:41

1 stop15h 36m

Ontario

Sat 14/3

13:40-12:00

1 stop15h 20m

£366

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 25/2

10:05-17:41

1 stop15h 36m

Ontario

Tue 17/3

13:40-12:00

1 stop15h 20m

£366

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 28/2

10:05-17:41

1 stop15h 36m

Ontario

Sat 14/3

13:40-12:00

1 stop15h 20m

£366

Flights are sorted by cheapest return flights first.

Deals found on 22/1

Showing 1-10 of 58 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 return 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 return flight from London to Ontario. Price data was last updated on 16 January 2026.

To ensure you get the cheapest price possible for a flight from London to Ontario, you should look to book at least 81 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.

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 £234). Flying from London to Ontario in July is currently the most expensive (average of £387). 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.

How much does it cost for a return flight from London to Ontario?

What’s the top stopover airport for flights from London to Ontario?

Share of one-stop return flights from London to Ontario chosen by Cheapflights users in the past 12 months, using the same stopover each way.

Dallas (DFW) – chosen by Cheapflights users on 29% of one-stop itineraries from London to Ontario on Cheapflights.

What’s the cheapest stopover airport for flights from London to Ontario?

Average return fare for one-stop flights from London to Ontario, chosen by Cheapflights users in the past 12 months, with the same stopover each way.

Lisbon (LIS) is the most affordable one-stop option, with an average return flight price of £386.

What’s the fastest stopover option from London to Ontario?

Shortest average travel time for one-stop one-way flights from London to Ontario, based on itineraries clicked by Cheapflights users over the past 12 months, grouped by stopover airport.

Flights via Denver (DEN) have the shortest average one-way travel time for one-stop routes: 13h 54m.

Which airport typically offers the quickest stopover for flights from London to Ontario?

Average stopover duration for one-stop one-way flights from London to Ontario, chosen by Cheapflights users in the last 12 months, grouped by stopover airport.

Flights via Seattle (SEA) offer the fastest connection on this route, with an average stopover time of 1h 20m.

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 25 January 2026.
Read through reviews of airlines operating flights from London to Ontario, such as Finnair, Virgin Atlantic, andUnited Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Finnair
7.6
Good
1,356 reviews
Check prices

Comfort

7.5

Food

6.7

Boarding

7.7

Overall

7.6

Entertainment

6.9

Crew

8.2

Reviews

1 / 20
2.0
Mediocre

Vlad-Valentin,Jan 2026

LHR - YVR

baggage allowance was different between the outgoing and inbound flights
Finnair
7.6
Good
1,356 reviews
Finnair
7.6
Good
1,356 reviews
Check prices

Comfort

7.5

Food

6.7

Boarding

7.7

Overall

7.6

Entertainment

6.9

Crew

8.2

Reviews

1 / 20
2.0
Mediocre

Vlad-Valentin,Jan 2026

LHR - YVR

baggage allowance was different between the outgoing and inbound flights
Virgin Atlantic
7.5
Good
678 reviews
Finnair
7.6
Good
1,356 reviews
Check prices

Comfort

7.5

Food

6.7

Boarding

7.7

Overall

7.6

Entertainment

6.9

Crew

8.2

Reviews

1 / 20
2.0
Mediocre

Vlad-Valentin,Jan 2026

LHR - YVR

baggage allowance was different between the outgoing and inbound flights
United Airlines
7.4
Good
9,198 reviews
Finnair
7.6
Good
1,356 reviews
Check prices

Comfort

7.5

Food

6.7

Boarding

7.7

Overall

7.6

Entertainment

6.9

Crew

8.2

Reviews

1 / 20
2.0
Mediocre

Vlad-Valentin,Jan 2026

LHR - YVR

baggage allowance was different between the outgoing and inbound flights
Lufthansa
6.8
Okay
7,748 reviews
Finnair
7.6
Good
1,356 reviews
Check prices

Comfort

7.5

Food

6.7

Boarding

7.7

Overall

7.6

Entertainment

6.9

Crew

8.2

Reviews

1 / 20
2.0
Mediocre

Vlad-Valentin,Jan 2026

LHR - YVR

baggage allowance was different between the outgoing and inbound flights
British Airways
6.7
Okay
7,699 reviews
Finnair
7.6
Good
1,356 reviews
Check prices

Comfort

7.5

Food

6.7

Boarding

7.7

Overall

7.6

Entertainment

6.9

Crew

8.2

Reviews

1 / 20
2.0
Mediocre

Vlad-Valentin,Jan 2026

LHR - YVR

baggage allowance was different between the outgoing and inbound flights

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?

    Most people fly into Ontario (ONT) if they book a flight to Ontario from London. On average, Ontario has 0 inbound flights from London per day from 6 airlines. Ontario is conveniently located just 3.1 mi from Ontario’s city center.

  • How long is the flight from London to Ontario?

    Airlines like United Airlines, Delta, and Iberia fly from London to Ontario in about 20h 15m. The time it takes to get you to your destination can typically vary by up to 2h 12m. The distance from London to Ontario is about 5422 mi. When browsing for deals, the options you’ll see will be for both direct flights and flights with stops.

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

    According to our current data, Finnair (£275), United Airlines (£363), and Virgin Atlantic (£370) offers the cheapest pricing from London to Ontario. You may be able to fly from London to Ontario for 46% less than the average price by searching for these airlines.

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

    The most popular route from London to Ontario is London Heathrow - Ontario. You may also consider London Gatwick - Ontario or London City - 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 holiday 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 £234). Flying from London to Ontario in July is currently the most expensive (average of £387). 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

See prices for flight routes from nearby airports that may be better suited for you.
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Top 6 airlines flying from London to Ontario

Discover the top 6 airlines 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 858,174 searches. Data last updated 25 January 2026.
AirlineCheapestAverageFlexibilityOn-time
FinnairCheapest£275Average£431FlexibilityNo cancel feeOn-time76%
Search Finnair flights
United AirlinesCheapest£363Average£514FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
Virgin AtlanticCheapest£370Average£491FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights
British AirwaysCheapest£379Average£465FlexibilityNo cancel feeOn-time70%
Search British Airways flights
KLMCheapest£388Average£605FlexibilityNo cancel feeOn-time75%
Search KLM flights
LufthansaCheapest£416Average£570FlexibilityNo cancel feeOn-time76%
Search Lufthansa flights

Fly with Cheapflights

Find the best flight deals on Cheapflights, where travellers can enjoy low prices and a wide availability of flights to their desired destinations.

How does Cheapflights help users find flights from London to Ontario?

When you search for this flight from London to Ontario, Cheapflights searches on 900+ travel sites to save you time finding great flight deals online. Additionally, we offer filter features so you can choose a preferred cabin class or airline, see different price ranges, and much more so you can book the flight for you.

Why should you use Cheapflights to find cheap flight tickets from London to Ontario?

Cheapflights helps you find that perfect flight to Ontario from London by searching from hundreds of airlines and agencies you know and love. We are also free to use, in case you were wondering!

Can Cheapflights find flights from London to Ontario with no change fees?

Cheapflights does show flights with no change fees to all users. To see these options for flights from London to Ontario, users can toggle the no change fees filter when performing a flight search.

Can Cheapflights notify me if prices for flights from London to Ontario become cheaper?

Yes, Cheapflights offers price alerts on London to Ontario flights so you can book your travel at the perfect time. Price Alerts can be enabled by clicking the bell icon next to the flight deals above and providing your email address where you want to receive the alerts.

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