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Cheap flights from London to Ontario from £274

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 7/1. Fares are subject to change and may not be available on all flights or dates of travel.
LON — ONT
1 Sep — 8 Sep1
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 2 August 2026.

Fri 11/1209:30
LHR
-
ONT
2 stops18h 50m
United Airlines
Thu 31/1206:00
ONT
-
LHR
1 stop17h 25m
United Airlines
Deal found 1/8£444
Fri 11/1209:30
LHR
-
ONT
2 stops18h 50m
United Airlines
Sun 27/1213:18
ONT
-
LHR
1 stop34h 07m
United Airlines
Deal found 28/7£446
Wed 18/1109:00
LHR
-
ONT
2 stops19h 15m
United Airlines
Thu 19/1106:00
ONT
-
LHR
1 stop17h 40m
United Airlines
Deal found 29/7£446
Wed 16/908:40
LHR
-
ONT
2 stops19h 21m
United Airlines
Mon 21/913:56
ONT
-
LHR
1 stop16h 14m
United Airlines
Deal found 29/7£449
Sat 29/808:45
LHR
-
ONT
2 stops19h 16m
United Airlines
Sat 5/907:00
ONT
-
LHR
2 stops15h 55m
United Airlines
Deal found 30/7£449
Fri 28/808:40
LHR
-
ONT
2 stops19h 21m
United Airlines
Fri 4/913:18
ONT
-
LHR
1 stop12h 22m
United Airlines
Deal found 31/7£451
Sat 12/907:25
LHR
-
ONT
2 stops23h 34m
United Airlines
Sat 19/913:18
ONT
-
LHR
1 stop15h 07m
United Airlines
Deal found 29/7£452
Fri 4/907:25
LHR
-
ONT
2 stops18h 46m
United Airlines
Fri 11/905:00
ONT
-
LHR
1 stop20h 40m
United Airlines
Deal found 30/7£452
Thu 17/909:30
LHR
-
ONT
2 stops20h 29m
United Airlines
Mon 21/905:00
ONT
-
LHR
2 stops22h 55m
United Airlines
Deal found 27/7£454
Sat 12/907:25
LHR
-
ONT
2 stops23h 34m
United Airlines
Fri 25/905:00
ONT
-
LHR
1 stop20h 40m
United Airlines
Deal found 31/7£454
Tue 1/907:25
LHR
-
ONT
2 stops18h 46m
United Airlines
Wed 9/913:18
ONT
-
LHR
1 stop15h 17m
United Airlines
Deal found 1/8£455
Fri 4/910:25
LGW
-
ONT
2 stops19h 27m
Delta
Fri 25/906:20
ONT
-
LGW
2 stops19h 05m
Delta
Deal found 28/7£511

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 2 August 2026.

Round-trip from

£444

One-way from

£274

Popular in

June

Cheapest in

September

Average price

£499
United Airlines
  • United Airlines
  • 11/12-31/12
  • 3 total stops
  • 36h 15m total
  • London to Ontario
Search Deals
Lufthansa
  • Lufthansa
  • 7/1
  • 1 total stop
  • 17h 16m total
  • London to Ontario
Search Deals
Highest demand for flights based on searches. 15% potential increase in price (£72 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease (£11 potential savings vs. average return price).
Search Deals
Average for round-trip flights in August 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 2 August 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

LHR - ONT

LHRONT

London Heathrow

Wed 27/1

06:50-18:44

2 stops19h 54m

Ontario

Fri 29/1

11:20-11:15

1 stop15h 55m

£476
Fastest return journey

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Thu 27/8

14:50-20:53

1 stop14h 03m

Ontario

Wed 9/9

13:18-09:40

1 stop12h 22m

£476

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 2/9

13:00-20:01

1 stop15h 01m

Ontario

Wed 9/9

09:01-07:25

1 stop14h 24m

£477

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 31/8

14:50-20:53

1 stop14h 03m

Ontario

Sun 13/9

13:18-12:35

1 stop15h 17m

£478

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 16/9

10:35-18:16

1 stop15h 41m

Ontario

Wed 23/9

13:56-11:10

1 stop13h 14m

£480

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sun 18/10

13:40-21:59

1 stop16h 19m

Ontario

Sun 25/10

13:35-11:15

1 stop14h 40m

£482

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sun 20/12

10:45-23:48

1 stop21h 03m

Ontario

Tue 5/1

15:30-10:40

1 stop35h 10m

£506

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 22/8

10:00-18:12

1 stop16h 12m

Ontario

Sat 5/9

13:18-12:25

1 stop15h 07m

£515

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sun 16/8

13:40-21:59

1 stop16h 19m

Ontario

Sun 23/8

13:56-11:10

1 stop13h 14m

£515

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 24/8

16:15-22:59

1 stop14h 44m

Ontario

Thu 24/9

13:52-11:10

1 stop13h 18m

£515

Flights are sorted by cheapest return flights first.

Deals found on 31/7

Showing 1-10 of 60 resultsSorted by cheapest first
1
2
3
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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, January is the cheapest month in which you can book a flight from London to Ontario (average of £410). Flying from London to Ontario in June is currently the most expensive (average of £654). 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?

Airfare is typical for this route at the moment.
London to Ontario flights typically cost between £400 and £551 in December.
The cheapest return price found within the last 5 days was £444 on United Airlines (11 Dec–31 Dec).

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.

Phoenix (PHX) is the most affordable one-stop option, with an average return flight price of £410.

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 47m.

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 37m.

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 2 August 2026.
Read through reviews of airlines operating flights from London to Ontario, such as Virgin Atlantic,United Airlines, andBritish Airways. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Virgin Atlantic
7.5
Good
694 reviews
Check prices

Overall

7.5

Food

6.9

Crew

8.1

Entertainment

7.5

Comfort

7.3

Boarding

7.7

Reviews

1 / 20
10.0
Excellent

Edwin,May 2026

LHR - LAX

First time flying with Virgin. It was everything I hoped it would be.
Virgin Atlantic
7.5
Good
694 reviews
Virgin Atlantic
7.5
Good
694 reviews
Check prices

Overall

7.5

Food

6.9

Crew

8.1

Entertainment

7.5

Comfort

7.3

Boarding

7.7

Reviews

1 / 20
10.0
Excellent

Edwin,May 2026

LHR - LAX

First time flying with Virgin. It was everything I hoped it would be.
United Airlines
7.4
Good
10,062 reviews
Virgin Atlantic
7.5
Good
694 reviews
Check prices

Overall

7.5

Food

6.9

Crew

8.1

Entertainment

7.5

Comfort

7.3

Boarding

7.7

Reviews

1 / 20
10.0
Excellent

Edwin,May 2026

LHR - LAX

First time flying with Virgin. It was everything I hoped it would be.
British Airways
6.7
Okay
8,136 reviews
Virgin Atlantic
7.5
Good
694 reviews
Check prices

Overall

7.5

Food

6.9

Crew

8.1

Entertainment

7.5

Comfort

7.3

Boarding

7.7

Reviews

1 / 20
10.0
Excellent

Edwin,May 2026

LHR - LAX

First time flying with Virgin. It was everything I hoped it would be.

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 United Airlines, Virgin Atlantic, and Delta fly from London to Ontario in about 18h 33m. 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, United Airlines (£368), Virgin Atlantic (£372), and British Airways (£398) offers the cheapest pricing from London to Ontario. You may be able to fly from London to Ontario for 29% 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, January is the cheapest month in which you can book a flight from London to Ontario (average of £410). Flying from London to Ontario in June is currently the most expensive (average of £654). 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 2 August 2026.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest£368Average£557FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
Virgin AtlanticCheapest£372Average£477FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights
British AirwaysCheapest£398Average£490FlexibilityNo 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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