How long is the flight from London to Ontario?

Airlines like American Airlines, British Airways, and Virgin Atlantic fly from London to Ontario in about 17h 26m. The time it takes to get you to your destination can typically vary by up to 22h 28m. 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 (£276), British Airways (£381), and United Airlines (£381) 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. American Airlines flights start at £313 while deals on Delta start at £332 one-way.

What is the cheapest day to fly from London to Ontario?

Travellers seeking maximum savings on their London to Ontario flight should consider departing on Tuesday afternoons when fares are most often at their lowest. Sunday at midday flights should be avoided if possible as fares are typically the most expensive at this time.

In terms of precipitation, rainfall in Ontario ranges from 3.0 - 86.0 inches per month. February is typically the wettest month, when rainfall can reach 86.0 mm. June is typically the driest time to visit Ontario when rainfall is around 3.0 mm.

If weather is an important factor for your trip to Ontario, use this chart to help with planning. For those seeking warmer temperatures, August is the ideal time of year to visit, when temperatures reach an average of 26.0 C. Travellers hoping to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 12.0 C).

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.

What are the most popular airlines that fly from London to Ontario?

When booking a flight from London to Ontario, you may want to consider flying on Finnair, British Airways or KLM as they are the most popular for this route.

What is the cheapest day to fly round-trip from London to Ontario?

Departing on a Tuesday is a good option for securing a great price. You can expect to save up to 15% when planning your travel around this day of the week.

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

When searching for a good deal, it’s best to be prepared for potential fluctuations in price. We recommend booking at least 56 days in advance, which can save you up to 37% on flights from London to Ontario compared to booking the week you need them. Waiting 56 days out may not be for everyone, so we have options available for flights within the next two weeks, with the lowest price starting at £411. For sooner than that we have options available in the next 3 days from £661.

What is the cheapest month to fly from London to Ontario?

Flights from London to Ontario lean towards being more expensive in December. Prices are generally better when you fly from London to Ontario in September, with the cheapest ticket starting at £301.

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.

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.

£298+ Cheap Flights from London to Ontario

Q: How much does it cost for a return flight from London to Ontario?

Airfare is below average for this route at the moment. London to Ontario flights typically cost between £396 and £457 in February. The cheapest return flight price found within the last 3 days was £361 on American Airlines (26 Feb-2 Mar).

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

Cheap flight deals from London to Ontario

Round-trip from	£361
One-way from	£298
Popular in	July
Cheapest in	February
Average price	£416

American Airlines
26/2-2/3
4 total stops
58h 07m total
London to Ontario

Search Deals

15/10
3 total stops
33h 05m total
London to Ontario

Search Deals

Highest demand for flights based on searches. 23% potential increase in price (£121 potential increase over avg. return price).

Search Deals

Cheapest flight prices on average. 6% potential price decrease (£25 potential savings vs. average return price).

Search Deals

Average for round-trip flights in September 2025

Search Deals

Find flight deals from London to Ontario

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 16 September 2025.

Wed 29/1020:25LHR - ONT

2 stops33h 16mVirgin Atlantic

Wed 5/1107:05ONT - LHR

1 stop17h 55mVirgin Atlantic

Deal found 14/9£363

Thu 30/1014:45LHR - ONT

1 stop14h 56mVirgin Atlantic

Thu 6/1107:35ONT - LHR

1 stop21h 15mVirgin Atlantic

Deal found 15/9£377

Wed 1/1012:20LGW - ONT

2 stops40h 51mAmerican Airlines

Sun 5/1023:59ONT - LGW

2 stops24h 11mAmerican Airlines

Deal found 15/9£379

Sat 15/1106:20LHR - ONT

2 stops23h 15mVirgin Atlantic

Sat 13/1213:20ONT - LHR

1 stop12h 40mVirgin Atlantic

Deal found 15/9£380

Sat 22/1116:25LHR - ONT

2 stops39h 27mVirgin Atlantic

Sat 29/1111:45ONT - LHR

1 stop36h 05mVirgin Atlantic

Deal found 14/9£383

Thu 30/1011:55LHR - ONT

1 stop17h 23mBritish Airways

Thu 6/1114:59ONT - LHR

1 stop12h 41mBritish Airways

Deal found 15/9£391

Wed 1/1010:30LHR - ONT

1 stop20h 03mBritish Airways

Wed 19/1116:47ONT - LHR

1 stop12h 28mBritish Airways

Deal found 15/9£392

Mon 22/915:10LHR - ONT

1 stop15h 23mBritish Airways

Wed 8/1014:51ONT - LHR

1 stop15h 34mBritish Airways

Deal found 15/9£393

Mon 22/917:25LHR - ONT

2 stops38h 17mVirgin Atlantic

Tue 7/1013:15ONT - LHR

2 stops15h 55mVirgin Atlantic

Deal found 15/9£394

Thu 30/1006:30LHR - ONT

2 stops19h 49mDelta

Thu 6/1107:35ONT - LHR

1 stop18h 55mDelta

Deal found 15/9£396

Wed 8/1010:00LCY - ONT

2 stops20h 41mVirgin Atlantic

Wed 15/1013:15ONT - LCY

2 stops21h 15mVirgin Atlantic

Deal found 15/9£410

Fri 10/1015:05LGW - ONT

2 stops35h 47mMultiple Airlines

Wed 22/1006:10ONT - LGW

2 stops18h 00mMultiple Airlines

Deal found 15/9£424

Best flights from London to Ontario
Discover carefully curated flight deals from London to Ontario that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 16 September 2025.

Thu 26/212:30LGW - ONT

2 stops39h 54mAmerican Airlines

Mon 2/306:47ONT - LGW

2 stops18h 13mAmerican Airlines

Deal found 13/9£361

Fri 21/1111:45LHR - ONT

1 stop17h 26mBritish Airways

Sun 30/1116:47ONT - LHR

1 stop12h 28mBritish Airways

Deal found 14/9£391

Sat 1/1110:05LHR - ONT

1 stop15h 47mMultiple Airlines

Fri 7/1115:08ONT - LHR

1 stop13h 07mMultiple Airlines

Deal found 14/9£391

Thu 30/1006:30LHR - ONT

2 stops19h 49mDelta

Thu 6/1106:00ONT - LHR

2 stops18h 45mDelta

Deal found 15/9£396

Wed 8/1010:00LCY - ONT

2 stops20h 41mVirgin Atlantic

Wed 15/1013:15ONT - LCY

2 stops21h 15mVirgin Atlantic

Deal found 15/9£410

Tue 10/311:45LGW - ONT

2 stops41h 17mIberia

Tue 24/306:00ONT - LGW

2 stops30h 00mIberia

Deal found 15/9£534

Wed 1/1012:20LGW - ONT

2 stops40h 51mAmerican Airlines

Sun 5/1023:59ONT - LGW

2 stops24h 11mAmerican Airlines

Deal found 15/9£379

Wed 1/1010:30LHR - ONT

1 stop20h 03mBritish Airways

Wed 19/1116:47ONT - LHR

1 stop12h 28mBritish Airways

Deal found 15/9£392

Sat 22/1106:30LHR - ONT

2 stops18h 39mDelta

Sat 29/1106:00ONT - LHR

2 stops20h 30mDelta

Deal found 14/9£407

Sat 15/1112:20LHR - ONT

1 stop18h 35mVirgin Atlantic

Tue 25/1107:05ONT - LHR

1 stop17h 55mVirgin Atlantic

Deal found 14/9£415

Fri 10/1015:05LGW - ONT

2 stops35h 47mMultiple Airlines

Wed 22/1006:10ONT - LGW

2 stops18h 00mMultiple Airlines

Deal found 15/9£424

Sun 16/1116:30LHR - ONT

1 stop15h 27mBritish Airways

Tue 25/1112:49ONT - LHR

1 stop14h 51mBritish Airways

Deal found 14/9£392

Last-minute flights from London to Ontario
Discover last-minute flight deals from London to Ontario. Data last updated 16 September 2025 and is based on user searches.

Sat 20/915:10LHR - ONT

1 stop15h 23mBritish Airways

Sun 5/1014:30ONT - LHR

1 stop14h 15mBritish Airways

Deal found 13/9£391

Mon 22/915:10LHR - ONT

1 stop15h 23mBritish Airways

Wed 8/1014:51ONT - LHR

1 stop15h 34mBritish Airways

Deal found 15/9£393

Mon 22/917:25LHR - ONT

2 stops38h 17mVirgin Atlantic

Tue 7/1013:15ONT - LHR

2 stops15h 55mVirgin Atlantic

Deal found 15/9£394

Wed 1/1012:20LGW - ONT

2 stops40h 51mAmerican Airlines

Sun 5/1023:59ONT - LGW

2 stops24h 11mAmerican Airlines

Deal found 15/9£379

Wed 1/1010:30LHR - ONT

1 stop20h 03mBritish Airways

Wed 19/1116:47ONT - LHR

1 stop12h 28mBritish Airways

Deal found 15/9£392

Wed 1/1011:00LHR - ONT

1 stop18h 24mBritish Airways

Sat 22/1116:47ONT - LHR

1 stop12h 28mBritish Airways

Deal found 15/9£400

Wed 8/1010:00LCY - ONT

2 stops20h 41mVirgin Atlantic

Wed 15/1013:15ONT - LCY

2 stops21h 15mVirgin Atlantic

Deal found 15/9£410

Tue 28/1010:45LHR - ONT

1 stop17h 35mVirgin Atlantic

Tue 4/1111:48ONT - LHR

1 stop14h 42mVirgin Atlantic

Deal found 13/9£375

Wed 29/1020:25LHR - ONT

2 stops33h 16mVirgin Atlantic

Wed 5/1107:05ONT - LHR

1 stop17h 55mVirgin Atlantic

Deal found 14/9£363

Thu 30/1014:45LHR - ONT

1 stop14h 56mVirgin Atlantic

Thu 6/1107:35ONT - LHR

1 stop21h 15mVirgin Atlantic

Deal found 15/9£377

Thu 30/1011:55LHR - ONT

1 stop17h 23mBritish Airways

Thu 6/1114:59ONT - LHR

1 stop12h 41mBritish Airways

Deal found 15/9£391

Thu 30/1006:30LHR - ONT

2 stops19h 49mDelta

Thu 6/1107:35ONT - LHR

1 stop18h 55mDelta

Deal found 15/9£396

One-way flights from London to Ontario
Search for one-way flight options from London to Ontario. Find affordable one-way fares based on user searches. Data last updated 16 September 2025.

Wed 15/1020:50LGW - ONT

3 stops33h 05mMultiple Airlines

Deal found 13/9£298

Mon 3/1108:25LHR - ONT

2 stops22h 04mAmerican Airlines

Deal found 13/9£311

Tue 20/106:05LHR - ONT

2 stops23h 57mBritish Airways

Deal found 14/9£313

Tue 11/1110:05LHR - ONT

1 stop16h 16mBritish Airways

Deal found 15/9£313

Mon 10/1112:30LGW - ONT

2 stops29h 27mAmerican Airlines

Deal found 14/9£313

Wed 18/206:20LHR - ONT

2 stops17h 59mVirgin Atlantic

Deal found 14/9£316

Wed 21/107:50LCY - ONT

2 stops22h 12mBritish Airways

Deal found 15/9£319

Mon 10/1114:45LHR - ONT

1 stop16h 10mVirgin Atlantic

Deal found 14/9£319

Wed 3/1216:30LHR - ONT

1 stop29h 30mMultiple Airlines

Deal found 15/9£320

Thu 30/1017:10LGW - ONT

3 stops37h 40mMultiple Airlines

Deal found 15/9£320

Wed 10/1209:55LHR - ONT

1 stop17h 44mBritish Airways

Deal found 15/9£322

Tue 2/1211:45LHR - ONT

1 stop15h 56mBritish Airways

Deal found 15/9£324

Fly from

Fly to

Route

Depart

Return

Price

LondonOntario

LGW - ONT

LGWONT

London Gatwick

Thu 26/2

12:30-20:24

2 stops39h 54m

Ontario

Mon 2/3

06:47-09:00

2 stops18h 13m

£361

LondonOntario

LGW - ONT

LGWONT

London Gatwick

Wed 1/10

12:20-21:11

2 stops40h 51m

Ontario

Sun 5/10

23:59-08:10

2 stops24h 11m

£379

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Fri 21/11

11:45-21:11

1 stop17h 26m

Ontario

Sun 30/11

16:47-13:15

1 stop12h 28m

£391

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 1/11

10:05-18:52

1 stop15h 47m

Ontario

Fri 7/11

15:08-12:15

1 stop13h 07m

£391

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 1/10

10:30-22:33

1 stop20h 03m

Ontario

Wed 19/11

16:47-13:15

1 stop12h 28m

£392

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sun 16/11

16:30-23:57

1 stop15h 27m

Ontario

Tue 25/11

12:49-11:40

1 stop14h 51m

£392

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 15/11

11:45-21:11

1 stop17h 26m

Ontario

Tue 25/11

16:47-13:15

1 stop12h 28m

£392

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 1/10

12:00-18:54

1 stop14h 54m

Ontario

Mon 24/11

15:19-12:15

1 stop12h 56m

£392

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 1/10

11:00-21:24

1 stop18h 24m

Ontario

Sun 23/11

12:49-10:00

1 stop13h 11m

£392

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 1/10

12:00-18:54

1 stop14h 54m

Ontario

Tue 25/11

14:59-11:40

1 stop12h 41m

£392

Flights are sorted by cheapest return flights first.

Deals found on 13/9

Showing 1-10 of 57 results

...

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?

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, March is the cheapest month in which you can book a flight from London to Ontario (average of £516). Flying from London to Ontario in August is currently the most expensive (average of £827). 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?

It’s optimal to fly from London to Ontario in the evening. By choosing this option you can save up to 15% 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?

Dallas (DFW) – chosen by Cheapflights users on 25% of one-stop itineraries from London to Ontario on Cheapflights.

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

Lisbon (LIS) is the most affordable one-stop option, with an average return flight price of £388.

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

Flights via Salt Lake City (SLC) have the shortest average one-way travel time for one-stop routes: 13h 34m.

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

Flights via Seattle (SEA) offer the fastest connection on this route, with an average stopover time of 1h 19m.

Reviews of airlines servicing Ontario

Read through reviews of airlines operating flights from London to Ontario, such as Finnair, United Airlines, andVirgin Atlantic. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.

Finnair

7.6

Good

1,323 reviews

Check prices

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

1,323 reviews

Finnair

7.6

Good

1,323 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Anonymous,May 2025

FRA - DFW

United Airlines

7.4

Good

8,929 reviews

Finnair

7.6

Good

1,323 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Anonymous,May 2025

FRA - DFW

Virgin Atlantic

7.4

Good

664 reviews

Finnair

7.6

Good

1,323 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Anonymous,May 2025

FRA - DFW

Lufthansa

6.8

Okay

7,407 reviews

Finnair

7.6

Good

1,323 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Anonymous,May 2025

FRA - DFW

British Airways

6.7

Okay

7,361 reviews

Finnair

7.6

Good

1,323 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Anonymous,May 2025

FRA - DFW

Related info for your journey

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 American Airlines, British Airways, and Virgin Atlantic fly from London to Ontario in about 17h 26m. The time it takes to get you to your destination can typically vary by up to 22h 28m. 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 (£276), British Airways (£381), and United Airlines (£381) 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. American Airlines flights start at £313 while deals on Delta start at £332 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, March is the cheapest month in which you can book a flight from London to Ontario (average of £516). Flying from London to Ontario in August is currently the most expensive (average of £827). 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

Browse thousands of different options on Cheapflights for your next trip

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Top 6 airlines flying from London to Ontario

Airline	Cheapest	Average	Flexibility	On-time
Finnair	Cheapest£276	Average£432	FlexibilityNo cancel fee	On-time76%	Search Finnair flights
British Airways	Cheapest£381	Average£461	FlexibilityNo cancel fee	On-time70%	Search British Airways flights
United Airlines	Cheapest£381	Average£638	FlexibilityNo cancel fee	On-time69%	Search United Airlines flights
KLM	Cheapest£390	Average£591	FlexibilityNo cancel fee	On-time75%	Search KLM flights
Virgin Atlantic	Cheapest£404	Average£503	FlexibilityNo cancel fee	On-time72%	Search Virgin Atlantic flights
Lufthansa	Cheapest£426	Average£570	FlexibilityNo cancel fee	On-time76%	Search Lufthansa flights

Fly with Cheapflights

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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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.

Cheap flights from London to Ontario from £298

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 15/10. Fares are subject to change and may not be available on all flights or dates of travel.

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

Cheap flight deals from London to Ontario

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Find flight deals from London to Ontario

Cheapest flights from London to OntarioExplore 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 16 September 2025.

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 16 September 2025.

Cheapflights Fare Finder

Use the filters below to find and compare flights from London to Ontario that are best for you.

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.

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 12 September 2025.

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

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 16 September 2025.

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.

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.

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.

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.

Reviews of airlines servicing Ontario

Read through reviews of airlines operating flights from London to Ontario, such as Finnair, United Airlines, andVirgin Atlantic. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.

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?

How long is the flight from London to Ontario?

What are the cheapest airlines flying from London to Ontario round-trip?

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

What are the most popular routes from London to Ontario?

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

How can I find direct flights from London to Ontario?

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

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

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Alternative routes for London to Ontario

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Top 6 airlines flying from London to Ontario

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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 16 September 2025.