Find flights
When to book
FAQs

Cheap flights from Ontario to London from £207

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 29/8. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — LON
24 Jul — 31 Jul1
1 adult
1 adult, Economy, 0 bags

Cheap flight deals from Ontario to London

Enter your travel dates to find the best prices.

Cheapest flights from Ontario to London
Explore the most affordable flight options available from Ontario to London. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 24 June 2026.

Fri 26/617:59
ONT
-
LHR
1 stop13h 36m
Virgin Atlantic
Sat 11/710:55
LHR
-
ONT
1 stop19h 28m
Virgin Atlantic
Deal found 23/6£322
Thu 17/1212:00
ONT
-
LHR
1 stop15h 40m
Virgin Atlantic
Tue 22/1212:20
LHR
-
ONT
1 stop18h 23m
Virgin Atlantic
Deal found 23/6£325
Tue 29/910:25
ONT
-
LHR
1 stop18h 25m
Multiple Airlines
Tue 13/1011:30
LHR
-
ONT
2 stops19h 36m
Multiple Airlines
Deal found 23/6£620
Mon 28/910:25
ONT
-
LHR
1 stop14h 40m
Multiple Airlines
Thu 1/1016:25
LHR
-
ONT
1 stop15h 11m
Multiple Airlines
Deal found 23/6£621
Sun 18/1006:00
ONT
-
LHR
2 stops20h 00m
Multiple Airlines
Thu 29/1008:20
LHR
-
ONT
1 stop19h 48m
Multiple Airlines
Deal found 21/6£624
Sun 20/912:12
ONT
-
LHR
1 stop18h 53m
Alaska Airlines
Sat 3/1017:00
LHR
-
ONT
1 stop14h 45m
Alaska Airlines
Deal found 19/6£626
Sun 9/807:05
ONT
-
LGW
2 stops18h 20m
Delta
Wed 19/810:25
LGW
-
ONT
2 stops20h 20m
Delta
Deal found 20/6£746
Mon 10/812:25
ONT
-
LGW
2 stops15h 20m
Multiple Airlines
Tue 25/813:00
LGW
-
ONT
2 stops17h 00m
Multiple Airlines
Deal found 23/6£750
Thu 10/911:54
ONT
-
LGW
2 stops20h 06m
Delta
Wed 28/1010:00
LGW
-
ONT
2 stops19h 43m
Delta
Deal found 22/6£756
Wed 19/810:55
ONT
-
LGW
2 stops16h 50m
Multiple Airlines
Tue 25/813:00
LGW
-
ONT
2 stops17h 00m
Multiple Airlines
Deal found 23/6£758
Tue 1/913:50
ONT
-
LGW
2 stops16h 50m
Multiple Airlines
Wed 16/915:40
LGW
-
ONT
2 stops38h 30m
Multiple Airlines
Deal found 20/6£759
Sun 22/1112:00
ONT
-
LGW
2 stops19h 45m
Delta
Tue 1/1210:00
LGW
-
ONT
2 stops20h 14m
Delta
Deal found 21/6£772

Find flight deals from Ontario to London

Discover tips and strategies to find the most affordable flight options for your journey from Ontario (ONT) to London (LON). 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 24 June 2026.

Round-trip from

£325

One-way from

£207

Popular in

June

Cheapest in

March

Average price

£1,169
Virgin Atlantic
  • Virgin Atlantic
  • 17/12-22/12
  • 2 total stops
  • 34h 03m total
  • Ontario to London
Search Deals
29/8
  • 29/8
  • 3 total stops
  • 51h 59m total
  • Ontario to London
Search Deals
Highest demand for flights based on searches. 32% potential increase in price (£235 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 7% potential price decrease (£36 potential savings vs. average return price).
Search Deals
Average for round-trip flights in June 2026
Search Deals

Cheapflights Fare Finder

 
Customise your flight search to find flights from Ontario to London 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 24 June 2026.
Use the filters below to find and compare flights from Ontario to London that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Tue 10/11

12:00-09:00

1 stop13h 00m

London Heathrow

Tue 17/11

10:45-16:12

1 stop13h 27m

£662

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Mon 9/11

12:00-09:00

1 stop13h 00m

London Heathrow

Wed 18/11

10:45-16:12

1 stop13h 27m

£677

OntarioLondon

ONT - LGW

ONTLGW

Ontario

Mon 10/8

12:25-11:45

2 stops15h 20m

London Gatwick

Tue 25/8

13:00-22:00

2 stops17h 00m

£750

OntarioLondon

ONT - LGW

ONTLGW

Ontario

Mon 27/7

14:30-14:40

2 stops16h 10m

London Gatwick

Tue 25/8

13:00-22:00

2 stops17h 00m

£751

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Tue 11/8

10:55-11:55

2 stops17h 00m

London Heathrow

Wed 19/8

13:05-22:00

2 stops16h 55m

£758

OntarioLondon

ONT - LGW

ONTLGW

Ontario

Sun 23/8

14:05-14:40

2 stops16h 35m

London Gatwick

Sun 30/8

13:00-22:00

2 stops17h 00m

£796

OntarioLondon

ONT - LGW

ONTLGW

Ontario

Mon 10/8

12:25-11:45

2 stops15h 20m

London Gatwick

Thu 20/8

13:00-22:10

2 stops17h 10m

£806
Fastest return journey

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Tue 28/7

13:18-09:40

1 stop12h 22m

London Heathrow

Wed 5/8

14:50-20:42

1 stop13h 52m

£806

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 16/9

21:10-20:45

1 stop15h 35m

London Heathrow

Mon 21/9

08:15-20:13

1 stop19h 58m

£827

OntarioLondon

ONT - LGW

ONTLGW

Ontario

Mon 21/9

21:10-09:55

2 stops28h 45m

London Gatwick

Sun 11/10

07:30-23:45

2 stops24h 15m

£864

Flights are sorted by cheapest return flights first.

Deals found on 20/6

Showing 1-10 of 60 resultsSorted by cheapest first
1
2
3
...
6

Best time to book a flight from Ontario to London

Have a flexible travel schedule? Discover the best time to fly to London from Ontario 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 Ontario to London

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

Currently, September is the cheapest month in which you can book a flight from Ontario to London (average of £190). Flying from Ontario to London in June is currently the most expensive (average of £836). 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 Ontario to London?

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

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

Dallas (DFW) – chosen by Cheapflights users on 50% of one-stop itineraries from Ontario to London on Cheapflights.

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

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

San Francisco (SFO) is the most affordable one-stop option, with an average return flight price of £683.

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

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

Flights via San Francisco (SFO) have the shortest average one-way travel time for one-stop routes: 13h 49m.

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

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

Flights via San Francisco (SFO) offer the fastest connection on this route, with an average stopover time of 2h 32m.

Related info for your journey

Find useful and relevant information for your journey from Ontario to London. 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 from for flights from Ontario to London?

    Ontario (ONT), located 3.1 mi from the city center, is the airport you fly out of when you book flights from Ontario to London. 0 airlines have flights from Ontario to London on a regular basis. Booking flights from Ontario to London should not be difficult; the airport handles an average of 0 outbound flights to London per day.

  • How long is the flight from Ontario to London?

    Airlines like United Airlines, JetBlue, and Iberia fly from Ontario to London in about 12h 22m. The time it takes to get you to your destination can typically vary by up to 6h 29m. The distance between Ontario and London is about 5407 mi. This flight may include one or multiple stops.

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

    When deciding which route to take from Ontario to London consider Ontario - London Heathrow, Ontario - London Gatwick or Ontario - London City as they are the most popular.

  • Can I find deals for flights from Ontario to London that include hotel bookings?

    Yes. In addition to deals on Ontario to London flights, Cheapflights offers holiday packages that include both flights and hotel.

  • How can I find direct flights from Ontario to London?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Ontario to London.

  • Can I find deals for business class flights from Ontario to London?

    Yes. Cheapflights offers flight deals from Ontario to London 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 Ontario to London?

    Currently, September is the cheapest month in which you can book a flight from Ontario to London (average of £190). Flying from Ontario to London in June is currently the most expensive (average of £836). 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

Travelling to a place near London?

Book flights to London if you plan to visit one of these locations
Hounslow
Milton Keynes
Wembley
Luton
Gatwick
Croydon
Ilford
Slough
Hayes
Brentford
Colchester
Kingston upon Thames
Eastbourne
Watford
Southall
Romford
Ipswich
Borehamwood
Folkestone
Southend-on-Sea

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

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 Ontario to London?

Cheapflights helps you search for flights from Ontario to London via 900+ travel sites so you don’t have to. After performing a flight search, users can also filter their flight selection by filtering for price, number of stops, airlines, and so on.

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

Cheapflights taps into our reliable network of hundreds of airlines and travel agencies to find the best deals for flights from Ontario to London for you. Better yet — we are completely free to use.

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

Yes! Cheapflights helps users easily find flights from Ontario to London with no change fees.

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

Yes! Start tracking prices for Ontario to London flights today and get alerted whenever prices for these flights change. To access this feature, click the bell icon next to the flight deals above, which will prompt you for a valid email address to receive your alerts.

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.