Cheap flights from London to Ontario from £310

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 2/2. Fares are subject to change and may not be available on all flights or dates of travel.
LON — ONT
11 Jan — 18 Jan1
1 adult
1 adult, Economy, 0 bags

Cheapflights Tip: The best prices from London to Ontario are usually found in January or September, booked 81 days in advance, depart on a Wednesday or Tuesday and return on a Monday

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 12 December 2025.

Mon 15/1214:45LHR - ONT
1 stop16h 02mVirgin Atlantic
Sat 10/106:00ONT - LHR
1 stop20h 00mVirgin Atlantic
Deal found 10/12£505
Mon 15/1211:45LHR - ONT
2 stops31h 17mDelta
Thu 8/107:30ONT - LHR
1 stop20h 25mDelta
Deal found 10/12£520
Sun 14/1206:20LHR - ONT
2 stops24h 27mDelta
Wed 15/413:00ONT - LHR
2 stops16h 10mDelta
Deal found 11/12£524
Sun 14/1206:20LHR - ONT
2 stops24h 44mDelta
Sat 10/113:11ONT - LHR
1 stop12h 49mDelta
Deal found 10/12£524
Mon 22/1216:30LHR - ONT
2 stops27h 23mAmerican Airlines
Wed 31/1212:45ONT - LHR
1 stop13h 15mAmerican Airlines
Deal found 10/12£528
Thu 25/1208:55LHR - ONT
1 stop18h 55mDelta
Wed 7/113:11ONT - LHR
1 stop12h 49mDelta
Deal found 11/12£530
Wed 24/1210:45LHR - ONT
1 stop19h 48mDelta
Wed 31/1206:00ONT - LHR
1 stop20h 00mDelta
Deal found 10/12£531
Tue 23/1210:45LHR - ONT
1 stop13h 27mDelta
Sat 10/113:11ONT - LHR
1 stop12h 49mDelta
Deal found 11/12£532
Sat 20/1210:45LHR - ONT
1 stop19h 43mDelta
Tue 30/1222:29ONT - LHR
2 stops24h 21mDelta
Deal found 10/12£532
Sat 13/1211:40LHR - ONT
2 stops18h 15mVirgin Atlantic
Thu 8/107:30ONT - LHR
1 stop19h 00mVirgin Atlantic
Deal found 9/12£533
Thu 11/1215:50LHR - ONT
1 stop27h 12mDelta
Mon 15/1207:05ONT - LHR
1 stop17h 55mDelta
Deal found 11/12£535
Mon 15/1211:40LHR - ONT
2 stops19h 07mVirgin Atlantic
Sun 11/107:30ONT - LHR
2 stops19h 10mVirgin Atlantic
Deal found 9/12£535

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 12 December 2025.

Round-trip from

£373

One-way from

£310

Popular in

July

Cheapest in

January

Average price

£600
United Airlines
  • United Airlines
  • 12/1-2/2
  • 2 total stops
  • 31h 15m total
  • London to Ontario
British Airways
  • British Airways
  • 2/2
  • 2 total stops
  • 35h 08m total
  • London to Ontario
Highest demand for flights based on searches. 21% potential increase in price (£107 potential increase over avg. return price).
Cheapest flight prices on average. 6% potential price decrease (£23 potential savings vs. average return price).
Average for round-trip flights in December 2025

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 12 December 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

LHR - ONT

LHRONT

London Heathrow

Mon 12/1

13:45-22:53

1 stop17h 08m

Ontario

Mon 2/2

13:53-12:00

1 stop14h 07m

£373

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 12/1

08:20-18:45

1 stop18h 25m

Ontario

Tue 3/2

07:16-10:00

1 stop18h 44m

£497

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 19/1

10:05-17:43

1 stop15h 38m

Ontario

Mon 26/1

13:24-09:40

1 stop12h 16m

£497

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 12/1

08:20-18:45

1 stop18h 25m

Ontario

Wed 4/2

07:16-11:40

1 stop20h 24m

£497

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 12/1

10:05-18:45

1 stop16h 40m

Ontario

Mon 2/2

07:16-11:40

1 stop20h 24m

£497

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Tue 3/2

10:05-17:55

1 stop15h 50m

Ontario

Wed 11/2

13:24-09:40

1 stop12h 16m

£497

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 28/3

16:10-11:35

2 stops26h 25m

Ontario

Sat 11/4

06:00-13:10

2 stops23h 10m

£500

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Thu 12/2

08:55-21:05

1 stop20h 10m

Ontario

Sat 28/2

13:15-11:40

1 stop14h 25m

£503

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Thu 22/1

07:30-21:58

2 stops22h 28m

Ontario

Mon 26/1

06:00-07:55

2 stops17h 55m

£506

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 1/4

11:20-17:13

1 stop13h 53m

Ontario

Tue 14/4

13:00-09:50

1 stop12h 50m

£512

Flights are sorted by cheapest return flights first.

Deals found on 10/12

Showing 1-10 of 59 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 5 December 2025.

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 £239). Flying from London to Ontario in July is currently the most expensive (average of £403). 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 12 December 2025.

It’s optimal to fly from London to Ontario in the evening. By choosing this option you can save up to 24% on the cost of your flight, compared to a flight at midday.

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 £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 Salt Lake City (SLC) have the shortest average one-way travel time for one-stop routes: 13h 28m.

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 Salt Lake City (SLC) offer the fastest connection on this route, with an average stopover time of 1h 11m.

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 12 December 2025.
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.

Comfort

7.4

Boarding

7.6

Food

6.7

Crew

8.1

Entertainment

6.9

Overall

7.6

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.

Comfort

7.4

Boarding

7.6

Food

6.7

Crew

8.1

Entertainment

6.9

Overall

7.6

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.

Comfort

7.4

Boarding

7.6

Food

6.7

Crew

8.1

Entertainment

6.9

Overall

7.6

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.

Comfort

7.4

Boarding

7.6

Food

6.7

Crew

8.1

Entertainment

6.9

Overall

7.6

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.

Comfort

7.4

Boarding

7.6

Food

6.7

Crew

8.1

Entertainment

6.9

Overall

7.6

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.

Comfort

7.4

Boarding

7.6

Food

6.7

Crew

8.1

Entertainment

6.9

Overall

7.6

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.

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, British Airways, and Iberia fly from London to Ontario in about 17h 08m. The time it takes to get you to your destination can typically vary by up to 15h 50m. 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, Finnair (£280), Virgin Atlantic (£376), and British Airways (£387) offers the cheapest pricing from London to Ontario. You may be able to fly from London to Ontario for 47% less than the average price by searching for these airlines.

  • 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 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 £239). Flying from London to Ontario in July is currently the most expensive (average of £403). 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.

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 12 December 2025.
AirlineCheapestAverageFlexibilityOn-time
FinnairCheapest£280Average£459FlexibilityNo cancel feeOn-time76%
Search Finnair flights
Virgin AtlanticCheapest£376Average£500FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights
British AirwaysCheapest£387Average£474FlexibilityNo cancel feeOn-time70%
Search British Airways flights
United AirlinesCheapest£387Average£561FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
KLMCheapest£395Average£617FlexibilityNo cancel feeOn-time75%
Search KLM flights
LufthansaCheapest£432Average£581FlexibilityNo 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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