How long is the flight from London to Ontario?

Airlines like Delta, American Airlines, and British Airways fly from London to Ontario in about 16h 50m. The time it takes to get you to your destination can typically vary by up to 19h 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 (£281), British Airways (£381), and United Airlines (£388) 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.

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 British Airways, Virgin Atlantic or Lufthansa as they are the most popular for this route.

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.

£310+ 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 £433 and £568 in February. The cheapest return flight price found within the last 3 days was £382 on Delta (26 Feb-2 Mar).

Cheapflights Tip: The best prices from London to Ontario are usually found in September 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	£382
One-way from	£310
Popular in	July
Cheapest in	September
Average price	£490

Delta
26/2-2/3
3 total stops
36h 35m total
London to Ontario

Search Deals

British Airways
3/2
2 total stops
24h 44m total
London to Ontario

Search Deals

Highest demand for flights based on searches. 22% potential increase in price (£120 potential increase over avg. return price).

Search Deals

Cheapest flight prices on average. 7% potential price decrease (£27 potential savings vs. average return price).

Search Deals

Average for round-trip flights in October 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 15 October 2025.

Sun 21/1210:45LHR - ONT

1 stop13h 27mDelta

Fri 9/106:45ONT - LHR

1 stop19h 45mDelta

Deal found 15/10£429

Mon 22/1214:45LHR - ONT

1 stop34h 23mDelta

Sun 28/1217:10ONT - LHR

1 stop32h 50mDelta

Deal found 14/10£430

Sat 13/1208:55LHR - ONT

1 stop21h 10mDelta

Wed 31/1211:15ONT - LHR

1 stop13h 45mDelta

Deal found 13/10£431

Thu 18/1208:55LHR - ONT

1 stop18h 44mKLM

Thu 8/122:30ONT - LHR

1 stop25h 20mKLM

Deal found 15/10£453

Tue 25/1114:45LHR - ONT

1 stop16h 10mVirgin Atlantic

Sat 24/113:00ONT - LHR

1 stop34h 50mVirgin Atlantic

Deal found 13/10£468

Tue 11/1113:30LHR - ONT

2 stops17h 21mMultiple Airlines

Tue 18/1107:00ONT - LHR

2 stops15h 20mMultiple Airlines

Deal found 14/10£468

Tue 9/1214:45LHR - ONT

1 stop16h 02mVirgin Atlantic

Sat 7/306:45ONT - LHR

1 stop22h 20mVirgin Atlantic

Deal found 13/10£469

Tue 11/1110:45LHR - ONT

1 stop21h 07mVirgin Atlantic

Tue 18/1111:48ONT - LHR

1 stop14h 42mVirgin Atlantic

Deal found 14/10£470

Tue 28/1012:20LHR - ONT

1 stop17h 21mVirgin Atlantic

Wed 3/1211:41ONT - LHR

1 stop36h 09mVirgin Atlantic

Deal found 14/10£471

Wed 22/1006:30LHR - ONT

2 stops17h 23mKLM

Wed 29/1011:36ONT - LHR

1 stop13h 14mKLM

Deal found 15/10£477

Tue 4/1114:30LHR - ONT

2 stops30h 07mAir Canada

Thu 13/1105:05ONT - LHR

2 stops18h 05mAir Canada

Deal found 15/10£478

Mon 3/1106:30LHR - ONT

2 stops20h 49mDelta

Mon 17/1107:05ONT - LHR

1 stop17h 55mDelta

Deal found 14/10£479

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 15 October 2025.

Thu 26/206:30LHR - ONT

2 stops16h 50mDelta

Mon 2/306:45ONT - LHR

1 stop19h 45mDelta

Deal found 14/10£382

Thu 26/212:30LGW - ONT

2 stops33h 14mAmerican Airlines

Mon 2/306:47ONT - LGW

2 stops18h 13mAmerican Airlines

Deal found 12/10£477

Tue 11/1109:50LCY - ONT

2 stops21h 01mMultiple Airlines

Tue 18/1107:00ONT - LCY

2 stops21h 50mMultiple Airlines

Deal found 14/10£489

Sat 15/1111:45LGW - ONT

2 stops32h 08mIberia

Sun 23/1107:00ONT - LGW

2 stops19h 50mIberia

Deal found 15/10£602

Wed 29/1017:00LCY - ONT

2 stops36h 18mBritish Airways

Sun 2/1123:59ONT - LCY

2 stops26h 51mBritish Airways

Deal found 14/10£627

Wed 1/410:00LCY - ONT

2 stops21h 52mKLM

Tue 14/412:00ONT - LCY

2 stops20h 40mKLM

Deal found 14/10£648

Wed 18/206:30LHR - ONT

2 stops22h 44mDelta

Sat 28/213:00ONT - LHR

1 stop13h 00mDelta

Deal found 13/10£423

Mon 15/1210:45LHR - ONT

1 stop16h 54mDelta

Tue 6/113:00ONT - LHR

1 stop13h 00mDelta

Deal found 12/10£431

Mon 17/1112:30LGW - ONT

2 stops31h 24mAmerican Airlines

Tue 2/1216:47ONT - LGW

2 stops30h 43mAmerican Airlines

Deal found 14/10£479

Thu 27/1109:40LCY - ONT

2 stops34h 57mMultiple Airlines

Thu 4/1213:50ONT - LCY

2 stops18h 50mMultiple Airlines

Deal found 13/10£513

Thu 18/1210:45LHR - ONT

1 stop21h 13mDelta

Tue 6/113:00ONT - LHR

1 stop13h 00mDelta

Deal found 12/10£431

Tue 16/1210:45LHR - ONT

1 stop21h 13mDelta

Wed 7/113:00ONT - LHR

1 stop13h 00mDelta

Deal found 12/10£431

Mon 15/1214:45LHR - ONT

1 stop16h 02mDelta

Mon 22/1213:15ONT - LHR

1 stop12h 45mDelta

Deal found 13/10£431

Sun 15/210:45LHR - ONT

1 stop18h 29mDelta

Mon 23/213:00ONT - LHR

1 stop13h 00mDelta

Deal found 13/10£437

Tue 11/1111:55LGW - ONT

2 stops35h 22mMultiple Airlines

Tue 18/1106:00ONT - LGW

2 stops20h 55mMultiple Airlines

Deal found 14/10£668

Wed 7/110:45LHR - ONT

1 stop18h 29mDelta

Wed 28/113:00ONT - LHR

1 stop13h 00mDelta

Deal found 13/10£437

Wed 7/110:45LHR - ONT

1 stop18h 29mDelta

Sat 24/113:00ONT - LHR

1 stop13h 00mDelta

Deal found 13/10£437

Wed 12/1111:55LGW - ONT

2 stops35h 22mMultiple Airlines

Mon 17/1118:11ONT - LGW

2 stops32h 44mMultiple Airlines

Deal found 13/10£735

Wed 18/212:20LHR - ONT

1 stop18h 18mDelta

Wed 25/213:00ONT - LHR

1 stop13h 00mDelta

Deal found 13/10£437

Thu 27/1111:55LGW - ONT

2 stops30h 00mMultiple Airlines

Thu 4/1219:33ONT - LGW

2 stops31h 22mMultiple Airlines

Deal found 13/10£752

Wed 7/120:00LHR - ONT

2 stops23h 38mDelta

Sat 10/122:30ONT - LHR

1 stop23h 55mDelta

Deal found 13/10£437

Mon 22/1210:45LCY - ONT

2 stops39h 31mBritish Airways

Sat 27/1223:59ONT - LCY

2 stops36h 46mBritish Airways

Deal found 14/10£1,058

Mon 3/1111:55LGW - ONT

2 stops19h 37mMultiple Airlines

Mon 17/1111:15ONT - LGW

2 stops15h 40mMultiple Airlines

Deal found 14/10£759

Wed 5/1111:55LGW - ONT

2 stops20h 01mMultiple Airlines

Wed 7/108:55ONT - LGW

2 stops18h 00mMultiple Airlines

Deal found 14/10£768

Sat 31/110:00LCY - ONT

2 stops19h 14mKLM

Thu 5/222:30ONT - LCY

2 stops25h 40mKLM

Deal found 14/10£3,487

Sat 1/1112:20LCY - ONT

2 stops42h 11mMultiple Airlines

Tue 4/1107:00ONT - LCY

2 stops21h 50mMultiple Airlines

Deal found 13/10£3,877

Last-minute flights from London to Ontario
Discover last-minute flight deals from London to Ontario. Data last updated 15 October 2025 and is based on user searches.

Fri 17/1018:00LHR - ONT

1 stop36h 41mVirgin Atlantic

Thu 23/1011:36ONT - LHR

1 stop15h 34mVirgin Atlantic

Deal found 15/10£477

Wed 22/1006:30LHR - ONT

2 stops17h 23mKLM

Wed 29/1011:36ONT - LHR

1 stop13h 14mKLM

Deal found 15/10£477

Wed 22/1008:40LHR - ONT

2 stops21h 42mDelta

Wed 29/1006:00ONT - LHR

2 stops18h 05mDelta

Deal found 14/10£480

Tue 28/1012:20LHR - ONT

1 stop17h 21mVirgin Atlantic

Wed 3/1211:41ONT - LHR

1 stop36h 09mVirgin Atlantic

Deal found 14/10£471

Mon 3/1106:30LHR - ONT

2 stops20h 49mDelta

Mon 17/1106:45ONT - LHR

2 stops18h 00mDelta

Deal found 14/10£479

Tue 4/1114:30LHR - ONT

2 stops30h 07mAir Canada

Thu 13/1105:05ONT - LHR

2 stops18h 05mAir Canada

Deal found 15/10£478

Tue 11/1113:30LHR - ONT

2 stops17h 21mMultiple Airlines

Tue 18/1107:00ONT - LHR

2 stops15h 20mMultiple Airlines

Deal found 14/10£468

Tue 11/1110:45LHR - ONT

1 stop21h 07mVirgin Atlantic

Tue 18/1111:48ONT - LHR

1 stop14h 42mVirgin Atlantic

Deal found 14/10£470

Tue 11/1109:50LCY - ONT

2 stops21h 01mMultiple Airlines

Tue 18/1107:00ONT - LCY

2 stops21h 50mMultiple Airlines

Deal found 14/10£489

Mon 17/1112:30LGW - ONT

2 stops31h 24mAmerican Airlines

Tue 2/1216:47ONT - LGW

2 stops30h 43mAmerican Airlines

Deal found 14/10£479

Thu 20/1114:45LHR - ONT

1 stop16h 10mVirgin Atlantic

Fri 5/1213:20ONT - LHR

1 stop12h 40mVirgin Atlantic

Deal found 15/10£466

Tue 25/1114:45LHR - ONT

1 stop16h 10mVirgin Atlantic

Sat 24/113:00ONT - LHR

1 stop34h 50mVirgin Atlantic

Deal found 13/10£468

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 15 October 2025.

Tue 3/206:05LHR - ONT

2 stops24h 44mBritish Airways

Deal found 15/10£310

Wed 11/206:15LHR - ONT

2 stops24h 34mBritish Airways

Deal found 12/10£311

Wed 18/206:20LHR - ONT

2 stops25h 32mVirgin Atlantic

Deal found 15/10£313

Wed 21/106:20LHR - ONT

2 stops25h 32mVirgin Atlantic

Deal found 14/10£314

Tue 2/1210:05LHR - ONT

1 stop16h 17mBritish Airways

Deal found 13/10£315

Wed 4/207:50LCY - ONT

2 stops22h 59mBritish Airways

Deal found 15/10£316

Mon 2/207:30LHR - ONT

2 stops23h 19mBritish Airways

Deal found 15/10£319

Mon 16/314:25LHR - ONT

1 stop14h 15mBritish Airways

Deal found 14/10£320

Tue 17/216:30LHR - ONT

1 stop15h 13mBritish Airways

Deal found 13/10£321

Wed 3/1212:35LHR - ONT

2 stops17h 53mMultiple Airlines

Deal found 14/10£322

Mon 2/211:45LGW - ONT

2 stops39h 00mBritish Airways

Deal found 15/10£331

Wed 3/1208:40LCY - ONT

2 stops22h 24mDelta

Deal found 14/10£332

Fly from

Fly to

Route

Depart

Return

Price

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Thu 26/2

06:30-15:20

2 stops16h 50m

Ontario

Mon 2/3

06:45-10:30

1 stop19h 45m

£382

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 18/2

06:30-21:14

2 stops22h 44m

Ontario

Sat 28/2

13:00-10:00

1 stop13h 00m

£423

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 15/12

10:45-19:39

1 stop16h 54m

Ontario

Tue 6/1

13:00-10:00

1 stop13h 00m

£431

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Thu 18/12

10:45-23:58

1 stop21h 13m

Ontario

Tue 6/1

13:00-10:00

1 stop13h 00m

£431

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Tue 16/12

10:45-23:58

1 stop21h 13m

Ontario

Wed 7/1

13:00-10:00

1 stop13h 00m

£431

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 15/12

14:45-22:47

1 stop16h 02m

Ontario

Mon 22/12

13:15-10:00

1 stop12h 45m

£431

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sun 15/2

10:45-21:14

1 stop18h 29m

Ontario

Mon 23/2

13:00-10:00

1 stop13h 00m

£437

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 7/1

10:45-21:14

1 stop18h 29m

Ontario

Wed 28/1

13:00-10:00

1 stop13h 00m

£437

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 7/1

10:45-21:14

1 stop18h 29m

Ontario

Sat 24/1

13:00-10:00

1 stop13h 00m

£437

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 18/2

12:20-22:38

1 stop18h 18m

Ontario

Wed 25/2

13:00-10:00

1 stop13h 00m

£437

Flights are sorted by cheapest return flights first.

Deals found on 15/10

Showing 1-10 of 52 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, 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 £416). 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 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?

Dallas (DFW) – chosen by Cheapflights users on 27% 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 £394.

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 33m.

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 25m.

Reviews of airlines servicing Ontario

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

1,332 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

1,332 reviews

Finnair

7.6

Good

1,332 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Anonymous,May 2025

FRA - DFW

Virgin Atlantic

7.5

Good

669 reviews

Finnair

7.6

Good

1,332 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Anonymous,May 2025

FRA - DFW

United Airlines

7.4

Good

8,979 reviews

Finnair

7.6

Good

1,332 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Anonymous,May 2025

FRA - DFW

Lufthansa

6.8

Okay

7,491 reviews

Finnair

7.6

Good

1,332 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Anonymous,May 2025

FRA - DFW

British Airways

6.7

Okay

7,456 reviews

Finnair

7.6

Good

1,332 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 Delta, American Airlines, and British Airways fly from London to Ontario in about 16h 50m. The time it takes to get you to your destination can typically vary by up to 19h 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 (£281), British Airways (£381), and United Airlines (£388) 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 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 £239). Flying from London to Ontario in July is currently the most expensive (average of £416). 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£281	Average£460	FlexibilityNo cancel fee	On-time76%	Search Finnair flights
British Airways	Cheapest£381	Average£466	FlexibilityNo cancel fee	On-time70%	Search British Airways flights
United Airlines	Cheapest£388	Average£649	FlexibilityNo cancel fee	On-time69%	Search United Airlines flights
KLM	Cheapest£396	Average£601	FlexibilityNo cancel fee	On-time75%	Search KLM flights
Virgin Atlantic	Cheapest£417	Average£513	FlexibilityNo cancel fee	On-time72%	Search Virgin Atlantic flights
Lufthansa	Cheapest£433	Average£582	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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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 3/2. 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 September 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 15 October 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 15 October 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 10 October 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 15 October 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, Virgin Atlantic, andUnited Airlines. 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 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

See prices for flight routes from nearby airports that may be better suited for you.

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 15 October 2025.