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Cheap flights from London to Ontario from £372

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 10/11. Fares are subject to change and may not be available on all flights or dates of travel.
LON — ONT
18 Jun — 25 Jun1
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 19 May 2026.

Mon 1/614:25
LHR
-
ONT
1 stop17h 34m
Iberia
Mon 15/612:41
ONT
-
LHR
1 stop16h 09m
Iberia
Deal found 17/5£447
Mon 16/1115:00
LHR
-
ONT
1 stop15h 23m
British Airways
Mon 23/1116:47
ONT
-
LHR
1 stop12h 28m
British Airways
Deal found 16/5£458
Wed 2/1215:00
LHR
-
ONT
1 stop15h 19m
British Airways
Tue 8/1214:56
ONT
-
LHR
1 stop13h 04m
British Airways
Deal found 17/5£464
Thu 24/911:40
LHR
-
ONT
1 stop19h 00m
Virgin Atlantic
Thu 8/1017:50
ONT
-
LHR
1 stop13h 45m
Virgin Atlantic
Deal found 15/5£465
Wed 10/616:25
LHR
-
ONT
1 stop15h 34m
British Airways
Mon 15/612:41
ONT
-
LHR
1 stop16h 09m
British Airways
Deal found 17/5£466
Thu 13/817:45
LHR
-
ONT
1 stop37h 00m
Virgin Atlantic
Wed 19/806:20
ONT
-
LHR
1 stop25h 15m
Virgin Atlantic
Deal found 15/5£468
Fri 19/611:40
LHR
-
ONT
1 stop19h 01m
Virgin Atlantic
Sat 4/713:00
ONT
-
LHR
2 stops16h 05m
Virgin Atlantic
Deal found 14/5£473
Wed 3/614:25
LHR
-
ONT
1 stop16h 13m
British Airways
Mon 8/612:41
ONT
-
LHR
1 stop16h 09m
British Airways
Deal found 15/5£477
Wed 5/809:20
LHR
-
ONT
1 stop33h 22m
Multiple Airlines
Thu 13/818:01
ONT
-
LHR
1 stop13h 34m
Multiple Airlines
Deal found 17/5£478
Wed 5/811:45
LHR
-
ONT
2 stops19h 49m
Virgin Atlantic
Thu 13/811:56
ONT
-
LHR
1 stop17h 19m
Virgin Atlantic
Deal found 15/5£481
Tue 13/1008:10
LCY
-
ONT
2 stops20h 58m
British Airways
Tue 20/1006:00
ONT
-
LCY
2 stops25h 15m
British Airways
Deal found 17/5£494
Mon 12/1009:35
LCY
-
ONT
2 stops31h 54m
British Airways
Mon 19/1023:59
ONT
-
LCY
2 stops31h 16m
British Airways
Deal found 17/5£495

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 19 May 2026.

Round-trip from

£447

One-way from

£372

Popular in

May

Cheapest in

September

Average price

£662
Iberia
  • Iberia
  • 1/6-15/6
  • 2 total stops
  • 33h 43m total
  • London to Ontario
Search Deals
United Airlines
  • United Airlines
  • 10/11
  • 2 total stops
  • 37h 58m total
  • London to Ontario
Search Deals
Highest demand for flights based on searches. 10% potential increase in price (£45 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease (£11 potential savings vs. average return price).
Search Deals
Average for round-trip flights in May 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 19 May 2026.
Use the filters below to find and compare flights from London to Ontario that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

LondonOntario

LCY - ONT

LCYONT

London City

Tue 13/10

08:10-21:08

2 stops20h 58m

Ontario

Tue 20/10

06:00-15:15

2 stops25h 15m

£494

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 5/8

11:45-23:34

2 stops19h 49m

Ontario

Thu 13/8

18:01-15:35

1 stop13h 34m

£495

LondonOntario

LCY - ONT

LCYONT

London City

Wed 14/10

09:35-18:57

2 stops41h 22m

Ontario

Sun 25/10

23:59-14:35

2 stops31h 36m

£495

LondonOntario

LCY - ONT

LCYONT

London City

Wed 14/10

09:35-18:57

2 stops41h 22m

Ontario

Tue 20/10

06:00-15:15

2 stops25h 15m

£495

LondonOntario

LCY - ONT

LCYONT

London City

Mon 12/10

09:35-09:29

2 stops31h 54m

Ontario

Wed 21/10

12:35-21:10

2 stops48h 35m

£495

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 23/9

13:25-21:56

1 stop16h 31m

Ontario

Fri 9/10

17:50-15:35

1 stop13h 45m

£502

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Thu 24/9

14:50-20:52

1 stop14h 02m

Ontario

Fri 2/10

13:18-09:40

1 stop12h 22m

£507

LondonOntario

LCY - ONT

LCYONT

London City

Mon 8/6

15:30-19:56

2 stops36h 26m

Ontario

Mon 15/6

23:59-11:30

2 stops27h 31m

£521

LondonOntario

LCY - ONT

LCYONT

London City

Tue 9/6

15:30-22:39

2 stops39h 09m

Ontario

Mon 15/6

23:59-11:30

2 stops27h 31m

£521

LondonOntario

LGW - ONT

LGWONT

London Gatwick

Sun 11/10

10:25-09:07

2 stops54h 42m

Ontario

Fri 23/10

22:59-10:00

2 stops51h 01m

£521

Flights are sorted by cheapest return flights first.

Deals found on 16/5

Showing 1-10 of 60 resultsSorted by cheapest first
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6

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

What is the cheapest month to book a flight from London to Ontario?

Currently, March is the cheapest month in which you can book a flight from London to Ontario (average of £297). Flying from London to Ontario in May is currently the most expensive (average of £422). 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 38% 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 £393.

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 48m.

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 Dallas (DFW) offer the fastest connection on this route, with an average stopover time of 1h 36m.

How far ahead should I book a flight from London to Ontario?

To ensure you get the cheapest price possible for a flight from London to Ontario, you should look to book at least 54 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.

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 19 May 2026.
Read through reviews of airlines operating flights from London to Ontario, such as United Airlines,Virgin Atlantic, andBritish Airways. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
United Airlines
7.4
Good
9,734 reviews
Check prices

Food

6.6

Boarding

7.7

Overall

7.4

Comfort

7.3

Entertainment

7.1

Crew

8.1

Reviews

1 / 20
10.0
Excellent

Tim,Sept 2025

LHR - IAD

The premium economy seats were very comfortable and the attention and service by the flight attendants was superb.
United Airlines
7.4
Good
9,734 reviews
United Airlines
7.4
Good
9,734 reviews
Check prices

Food

6.6

Boarding

7.7

Overall

7.4

Comfort

7.3

Entertainment

7.1

Crew

8.1

Reviews

1 / 20
10.0
Excellent

Tim,Sept 2025

LHR - IAD

The premium economy seats were very comfortable and the attention and service by the flight attendants was superb.
Virgin Atlantic
7.4
Good
688 reviews
United Airlines
7.4
Good
9,734 reviews
Check prices

Food

6.6

Boarding

7.7

Overall

7.4

Comfort

7.3

Entertainment

7.1

Crew

8.1

Reviews

1 / 20
10.0
Excellent

Tim,Sept 2025

LHR - IAD

The premium economy seats were very comfortable and the attention and service by the flight attendants was superb.
British Airways
6.7
Okay
7,988 reviews
United Airlines
7.4
Good
9,734 reviews
Check prices

Food

6.6

Boarding

7.7

Overall

7.4

Comfort

7.3

Entertainment

7.1

Crew

8.1

Reviews

1 / 20
10.0
Excellent

Tim,Sept 2025

LHR - IAD

The premium economy seats were very comfortable and the attention and service by the flight attendants was superb.

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 3 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 British Airways, Virgin Atlantic, and Delta fly from London to Ontario in about 16h 31m. The time it takes to get you to your destination can typically vary by up to 4h 27m. The distance from London to Ontario is about 5407 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, United Airlines (£370), Virgin Atlantic (£374), and British Airways (£383) offers the cheapest pricing from London to Ontario. You may be able to fly from London to Ontario for 26% 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, March is the cheapest month in which you can book a flight from London to Ontario (average of £297). Flying from London to Ontario in May is currently the most expensive (average of £422). 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 3 airlines flying from London to Ontario

Discover the top 3 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 19 May 2026.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest£370Average£476FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
Virgin AtlanticCheapest£374Average£494FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights
British AirwaysCheapest£383Average£489FlexibilityNo cancel feeOn-time70%
Search British Airways 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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