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Cheap flights from London to Ontario from £313

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 28/1. Fares are subject to change and may not be available on all flights or dates of travel.
LON — ONT
21 Dec — 28 Dec1
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

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 21 November 2025.

Round-trip from

£379

One-way from

£313

Popular in

July

Cheapest in

January

Average price

£536
Virgin Atlantic
  • Virgin Atlantic
  • 24/1-31/1
  • 2 total stops
  • 35h 46m total
  • London to Ontario
Search Deals
British Airways
  • British Airways
  • 12/1
  • 2 total stops
  • 27h 33m total
  • London to Ontario
Search Deals
Highest demand for flights based on searches. 22% potential increase in price (£122 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 6% potential price decrease (£27 potential savings vs. average return price).
Search Deals
Average for round-trip flights in November 2025
Search Deals

Find 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 21 November 2025.

Wed 3/1210:45LHR - ONT
1 stop21h 13mVirgin Atlantic
Sat 13/1213:29ONT - LHR
1 stop12h 31mVirgin Atlantic
Deal found 20/11£471
Tue 25/1112:20LHR - ONT
1 stop18h 35mVirgin Atlantic
Tue 2/1213:29ONT - LHR
1 stop12h 31mVirgin Atlantic
Deal found 20/11£471
Thu 18/1211:40LHR - ONT
2 stops20h 18mVirgin Atlantic
Wed 31/1207:05ONT - LHR
1 stop17h 55mVirgin Atlantic
Deal found 20/11£481
Thu 25/1206:30LHR - ONT
2 stops21h 20mDelta
Tue 6/115:30ONT - LHR
1 stop13h 20mDelta
Deal found 19/11£483
Wed 24/1210:45LHR - ONT
1 stop19h 48mDelta
Tue 6/115:30ONT - LHR
1 stop13h 20mDelta
Deal found 19/11£487
Mon 15/1214:45LHR - ONT
1 stop16h 02mDelta
Thu 26/215:30ONT - LHR
1 stop13h 20mDelta
Deal found 20/11£489
Sat 13/1215:05LHR - ONT
1 stop15h 42mDelta
Wed 14/113:10ONT - LHR
1 stop12h 50mDelta
Deal found 19/11£490
Wed 26/1110:45LHR - ONT
1 stop16h 57mDelta
Sun 7/1207:05ONT - LHR
1 stop15h 20mDelta
Deal found 19/11£495
Thu 20/1115:50LHR - ONT
1 stop27h 16mDelta
Mon 24/1107:05ONT - LHR
1 stop16h 45mDelta
Deal found 20/11£497
Wed 19/1112:30LHR - ONT
1 stop18h 34mDelta
Sun 23/1112:16ONT - LHR
1 stop15h 24mDelta
Deal found 19/11£497
Sun 14/1209:55LHR - ONT
1 stop19h 12mBritish Airways
Sat 18/415:05ONT - LHR
1 stop13h 05mBritish Airways
Deal found 20/11£504
Thu 18/1214:45LHR - ONT
1 stop16h 02mKLM
Wed 31/1207:05ONT - LHR
1 stop16h 45mKLM
Deal found 20/11£505

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 21 November 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

Wed 18/2

10:00-22:40

2 stops44h 40m

Ontario

Sun 22/2

07:30-10:30

1 stop19h 00m

£389

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 18/2

06:30-21:07

2 stops22h 37m

Ontario

Sun 22/2

22:20-06:20

2 stops24h 00m

£389

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 24/1

08:40-21:05

2 stops20h 25m

Ontario

Sat 31/1

06:00-09:05

2 stops19h 05m

£389

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 14/3

15:05-22:38

1 stop14h 33m

Ontario

Sat 4/4

13:00-09:50

1 stop12h 50m

£401

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 28/3

11:20-21:52

2 stops17h 32m

Ontario

Sat 11/4

06:45-14:15

1 stop23h 30m

£408

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Tue 31/3

11:20-17:15

1 stop13h 55m

Ontario

Tue 7/4

13:00-09:50

1 stop12h 50m

£408

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 16/3

14:45-22:38

1 stop14h 53m

Ontario

Mon 6/4

13:00-09:50

1 stop12h 50m

£408

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 15/4

10:55-16:14

1 stop13h 19m

Ontario

Mon 20/4

13:00-09:50

1 stop12h 50m

£414

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Tue 14/4

10:55-16:14

1 stop13h 19m

Ontario

Mon 20/4

13:00-09:50

1 stop12h 50m

£414

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 15/4

10:55-16:14

1 stop13h 19m

Ontario

Tue 21/4

13:00-09:50

1 stop12h 50m

£414

Flights are sorted by cheapest return flights first.

Deals found on 20/11

Showing 1-10 of 56 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 14 November 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 £245). Flying from London to Ontario in July is currently the most expensive (average of £418). 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 21 November 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 28% 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 £403.

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 33m.

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 25m.

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 21 November 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.
Finnair
7.6
Good
1,334 reviews
Check prices

Crew

8.1

Comfort

7.4

Entertainment

6.9

Boarding

7.6

Overall

7.6

Food

6.7

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.
Finnair
7.6
Good
1,334 reviews
Finnair
7.6
Good
1,334 reviews
Check prices

Crew

8.1

Comfort

7.4

Entertainment

6.9

Boarding

7.6

Overall

7.6

Food

6.7

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.
Virgin Atlantic
7.5
Good
674 reviews
Finnair
7.6
Good
1,334 reviews
Check prices

Crew

8.1

Comfort

7.4

Entertainment

6.9

Boarding

7.6

Overall

7.6

Food

6.7

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.
United Airlines
7.4
Good
9,029 reviews
Finnair
7.6
Good
1,334 reviews
Check prices

Crew

8.1

Comfort

7.4

Entertainment

6.9

Boarding

7.6

Overall

7.6

Food

6.7

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.
Lufthansa
6.8
Okay
7,579 reviews
Finnair
7.6
Good
1,334 reviews
Check prices

Crew

8.1

Comfort

7.4

Entertainment

6.9

Boarding

7.6

Overall

7.6

Food

6.7

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.
British Airways
6.7
Okay
7,533 reviews
Finnair
7.6
Good
1,334 reviews
Check prices

Crew

8.1

Comfort

7.4

Entertainment

6.9

Boarding

7.6

Overall

7.6

Food

6.7

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 Virgin Atlantic, Delta, and KLM fly from London to Ontario in about 14h 33m. The time it takes to get you to your destination can typically vary by up to 30h 07m. 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 (£287), British Airways (£396), and United Airlines (£396) offers the cheapest pricing from London to Ontario. You may be able to fly from London to Ontario for 48% less than the average price by searching for these airlines.

  • What are the cheapest airlines to fly from London to Ontario one-way?

    To fly one-way, consider booking your trip with British Airways, which is currently one of the cheapest options available, starting at £313. United Airlines flights start at £322 while deals on Iberia start at £342 one-way.

  • 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 £245). Flying from London to Ontario in July is currently the most expensive (average of £418). 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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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 21 November 2025.
AirlineCheapestAverageFlexibilityOn-time
FinnairCheapest£287Average£509FlexibilityNo cancel feeOn-time76%
Search Finnair flights
British AirwaysCheapest£396Average£478FlexibilityNo cancel feeOn-time70%
Search British Airways flights
United AirlinesCheapest£396Average£660FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
KLMCheapest£405Average£614FlexibilityNo cancel feeOn-time75%
Search KLM flights
Virgin AtlanticCheapest£420Average£520FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights
LufthansaCheapest£443Average£595FlexibilityNo 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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