How long is the flight from Ontario to London?

United Airlines, Delta, and Iberia can get you from Ontario to London in just under 12h 06m. Your travel time can differ by up to 7h 54m. Airlines will cover a distance of 5407 mi. This flight may include one or multiple stops.

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

Flying on Virgin Atlantic is currently your cheapest option to London, with prices starting at $469. Additional round-trip tickets that might be worth considering are offered by Delta and KLM, with the lowest prices starting at $572 and $580, respectively. You may be able to fly from Ontario to London for 40% less than the average price by searching for these airlines.

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

The cheapest airlines for a one-way flight from Ontario to London are British Airways ($395), United Airlines ($403), and Delta ($403).

In terms of precipitation, rainfall in London ranges from 1.6 - 2.8 inches per month. January is typically the wettest month, when rainfall can reach 2.8 in. July is typically the driest time to visit London when rainfall is around 1.6 in.

If weather is an important factor for your trip to London, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 62.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 39.2 F).

What are the most popular routes from Ontario to London?

The most popular flight routes from Ontario to London are Ontario - London Heathrow, Ontario - London Gatwick and Ontario - London City.

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

Before booking your flight from Ontario to London check out the most popular airlines for this route: American Airlines, British Airways or Delta.

Most accurate provider : When it comes to deals on Ontario-London flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Ontario-London flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Ontario-London flight searches over the past month and is updated monthly.

Most trusted provider : When it comes to deals on Ontario-London flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Ontario-London flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

What airport do you fly from for flights from Ontario to London?

Most people fly from Ontario (ONT) if they book a flight from Ontario to London. On average, Ontario has 0 outbound flights to London per day from 7 airlines. Ontario is conveniently located just 3.1 mi from Ontario’s city center.

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 vacation 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.

$259+ Cheap Flights from Ontario to London

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Find cheap flights from Ontario to London with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

Cheap flight deals from Ontario to London

Most accurate provider	FlightHub 3 stars
Most trusted provider	FlightHub 3 stars
Round-trip from	$628 (lol.travel)
One-way from	$259 (Kiwi.com)
Popular in	June
Cheapest in	October
Average price	$676

Provider with most accurate pricing for Ontario-London (LON) flight deals.

Search Deals

Provider most trusted by Cheapflights users for Ontario-London (LON) flights.

Search Deals

From Ontario to London (LON)

Search Deals

One-way flight from Ontario to London (LON)

Search Deals

Highest demand for flights based on searches. 12% potential increase in price ($118 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 3% potential price decrease ($24 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in October 2025

Search Deals

Find flight deals from Ontario to London

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 October 3, 2025.

Sun 11/161:40 pmONT - LHR

1 stop14h 20mUnited Airlines

Tue 11/251:45 pmLHR - ONT

1 stop17h 06mUnited Airlines

Deal found 10/1

$628

Tue 11/187:05 amONT - LHR

1 stop16h 45mDelta

Tue 11/256:30 amLHR - ONT

2 stops18h 39mDelta

Deal found 10/2

$652

Tue 10/215:05 amONT - LHR

2 stops17h 25mMultiple Airlines

Tue 10/282:30 pmLHR - ONT

2 stops29h 07mMultiple Airlines

Deal found 10/3

$657

Tue 12/21:34 pmONT - LHR

1 stop12h 06mUnited Airlines

Wed 12/109:30 amLHR - ONT

2 stops20h 19mUnited Airlines

Deal found 10/2

$661

Wed 10/225:05 amONT - LHR

2 stops22h 45mAir Canada

Wed 10/292:30 pmLHR - ONT

2 stops39h 21mAir Canada

Deal found 10/2

$663

Sat 10/256:36 pmONT - LHR

1 stop29h 49mUnited Airlines

Tue 12/99:30 amLHR - ONT

2 stops20h 19mUnited Airlines

Deal found 10/2

$666

Sun 10/197:02 amONT - LHR

1 stop15h 18mUnited Airlines

Tue 11/410:05 amLHR - ONT

1 stop15h 29mUnited Airlines

Deal found 10/2

$669

Sun 10/194:49 pmONT - LHR

1 stop12h 01mBritish Airways

Thu 10/3010:05 amLHR - ONT

1 stop15h 48mBritish Airways

Deal found 10/2

$673

Wed 10/2211:48 amONT - LHR

1 stop18h 27mDelta

Wed 10/296:20 amLHR - ONT

2 stops22h 00mDelta

Deal found 10/2

$677

Wed 10/2210:57 amONT - LHR

1 stop14h 03mIberia

Tue 11/43:00 pmLHR - ONT

1 stop15h 29mIberia

Deal found 9/30

$679

Wed 12/101:20 pmONT - LHR

1 stop12h 40mDelta

Thu 12/2510:45 amLHR - ONT

1 stop17h 05mDelta

Deal found 10/2

$680

Tue 11/187:00 amONT - LCY

2 stops26h 05mMultiple Airlines

Tue 11/259:50 amLCY - ONT

2 stops21h 01mMultiple Airlines

Deal found 10/2

$695

Best flights from Ontario to London
Discover carefully curated flight deals from Ontario to London that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated October 3, 2025.

Tue 12/21:34 pmONT - LHR

1 stop12h 06mUnited Airlines

Wed 12/109:30 amLHR - ONT

2 stops20h 19mUnited Airlines

Deal found 10/2

$661

Wed 3/46:00 amONT - LHR

1 stop20h 00mDelta

Tue 3/176:20 amLHR - ONT

2 stops16h 59mDelta

Deal found 10/2

$665

Mon 11/103:08 pmONT - LHR

1 stop13h 07mMultiple Airlines

Wed 11/1911:45 amLHR - ONT

1 stop15h 56mMultiple Airlines

Deal found 10/1

$680

Tue 12/27:00 amONT - LCY

2 stops17h 50mIberia

Wed 12/107:50 amLCY - ONT

2 stops22h 38mIberia

Deal found 10/2

$733

Wed 3/46:47 amONT - LGW

2 stops18h 13mAmerican Airlines

Sun 3/812:30 pmLGW - ONT

2 stops32h 10mAmerican Airlines

Deal found 10/1

$1,000

Wed 12/101:20 pmONT - LHR

1 stop12h 40mDelta

Wed 12/2410:45 amLHR - ONT

1 stop17h 05mDelta

Deal found 10/2

$680

Wed 1/76:00 amONT - LHR

1 stop17h 25mUnited Airlines

Tue 2/312:05 pmLHR - ONT

1 stop17h 53mUnited Airlines

Deal found 10/1

$680

Tue 11/410:47 amONT - LHR

1 stop13h 48mMultiple Airlines

Tue 11/113:00 pmLHR - ONT

1 stop15h 29mMultiple Airlines

Deal found 10/1

$680

Mon 11/241:29 pmONT - LHR

1 stop12h 11mUnited Airlines

Wed 12/310:05 amLHR - ONT

1 stop15h 32mUnited Airlines

Deal found 10/1

$680

Tue 12/91:20 pmONT - LHR

1 stop12h 40mDelta

Tue 12/2310:45 amLHR - ONT

1 stop13h 27mDelta

Deal found 10/2

$680

Tue 11/187:00 amONT - LCY

2 stops26h 05mMultiple Airlines

Tue 11/259:50 amLCY - ONT

2 stops21h 01mMultiple Airlines

Deal found 10/2

$695

Tue 1/66:00 amONT - LHR

1 stop20h 15mUnited Airlines

Thu 1/2910:00 amLHR - ONT

1 stop19h 58mUnited Airlines

Deal found 10/1

$680

Sun 2/156:47 amONT - LGW

2 stops20h 03mIberia

Sat 2/2111:45 amLGW - ONT

2 stops33h 59mIberia

Deal found 10/2

$854

Wed 3/46:00 amONT - LCY

3 stops19h 05mMultiple Airlines

Tue 3/179:50 amLCY - ONT

2 stops19h 55mMultiple Airlines

Deal found 10/1

$706

Sun 1/116:00 amONT - LHR

2 stops16h 20mUnited Airlines

Fri 1/3012:05 pmLHR - ONT

1 stop17h 53mUnited Airlines

Deal found 10/1

$684

Mon 1/126:00 amONT - LHR

2 stops16h 20mUnited Airlines

Wed 1/2810:25 amLHR - ONT

2 stops18h 33mUnited Airlines

Deal found 10/1

$684

Mon 12/11:40 pmONT - LCY

2 stops20h 00mMultiple Airlines

Mon 12/86:15 pmLCY - ONT

2 stops36h 34mMultiple Airlines

Deal found 10/1

$760

Sun 3/16:47 amONT - LGW

2 stops20h 03mIberia

Tue 4/2811:35 amLGW - ONT

2 stops20h 05mIberia

Deal found 10/1

$920

Sat 11/157:00 amONT - LCY

3 stops21h 40mMultiple Airlines

Sat 11/2212:20 pmLCY - ONT

2 stops42h 11mMultiple Airlines

Deal found 10/1

$784

Mon 11/241:40 pmONT - LCY

2 stops19h 00mMultiple Airlines

Mon 12/16:15 pmLCY - ONT

2 stops36h 34mMultiple Airlines

Deal found 10/1

$865

Fri 1/96:00 amONT - LCY

3 stops21h 40mMultiple Airlines

Sat 1/3112:20 pmLCY - ONT

3 stops42h 33mMultiple Airlines

Deal found 10/2

$897

Wed 3/45:40 amONT - LCY

3 stops19h 25mMultiple Airlines

Sun 3/85:15 pmLCY - ONT

2 stops34h 02mMultiple Airlines

Deal found 10/1

$926

Wed 12/311:15 amONT - LGW

2 stops15h 40mMultiple Airlines

Tue 1/1311:55 amLGW - ONT

2 stops17h 50mMultiple Airlines

Deal found 10/1

$970

Tue 11/411:15 amONT - LGW

2 stops15h 40mMultiple Airlines

Tue 11/1111:55 amLGW - ONT

2 stops18h 10mMultiple Airlines

Deal found 10/1

$970

Tue 11/1111:15 amONT - LGW

2 stops15h 40mMultiple Airlines

Mon 11/1711:55 amLGW - ONT

2 stops19h 37mMultiple Airlines

Deal found 10/1

$1,000

Tue 11/1811:15 amONT - LGW

2 stops15h 40mMultiple Airlines

Tue 11/2511:55 amLGW - ONT

2 stops20h 10mMultiple Airlines

Deal found 10/2

$1,005

Wed 3/46:00 amONT - LGW

2 stops20h 55mMultiple Airlines

Sun 3/811:55 amLGW - ONT

2 stops17h 40mMultiple Airlines

Deal found 10/1

$1,035

Mon 11/1010:50 amONT - LGW

2 stops16h 05mMultiple Airlines

Wed 11/1911:55 amLGW - ONT

2 stops20h 01mMultiple Airlines

Deal found 10/1

$1,085

Last-minute flights from Ontario to London
Discover last-minute flight deals from Ontario to London. Data last updated October 3, 2025 and is based on user searches.

Sun 10/197:02 amONT - LHR

1 stop15h 18mUnited Airlines

Tue 11/410:05 amLHR - ONT

1 stop15h 29mUnited Airlines

Deal found 10/2

$669

Sun 10/194:49 pmONT - LHR

1 stop12h 01mBritish Airways

Thu 10/3010:05 amLHR - ONT

1 stop15h 48mBritish Airways

Deal found 10/2

$673

Sun 10/191:53 pmONT - LHR

1 stop12h 32mUnited Airlines

Thu 10/3010:05 amLHR - ONT

1 stop14h 29mUnited Airlines

Deal found 10/2

$680

Tue 10/215:05 amONT - LHR

2 stops17h 25mMultiple Airlines

Tue 10/282:30 pmLHR - ONT

2 stops29h 07mMultiple Airlines

Deal found 10/3

$657

Wed 10/225:05 amONT - LHR

2 stops22h 45mAir Canada

Wed 10/292:30 pmLHR - ONT

2 stops39h 21mAir Canada

Deal found 10/2

$663

Wed 10/2211:48 amONT - LHR

1 stop18h 27mDelta

Wed 10/296:20 amLHR - ONT

2 stops22h 00mDelta

Deal found 10/2

$677

Wed 10/2210:57 amONT - LHR

1 stop14h 03mIberia

Tue 11/43:00 pmLHR - ONT

1 stop15h 29mIberia

Deal found 9/30

$679

Sat 10/256:36 pmONT - LHR

1 stop29h 49mUnited Airlines

Tue 12/99:30 amLHR - ONT

2 stops20h 19mUnited Airlines

Deal found 10/2

$666

Sun 11/912:53 pmONT - LHR

1 stop13h 07mIberia

Tue 11/254:30 pmLHR - ONT

1 stop15h 27mIberia

Deal found 10/1

$681

Sun 11/161:40 pmONT - LHR

1 stop14h 20mUnited Airlines

Tue 11/251:45 pmLHR - ONT

1 stop17h 06mUnited Airlines

Deal found 10/1

$628

Tue 11/187:05 amONT - LHR

1 stop16h 45mDelta

Tue 11/256:30 amLHR - ONT

2 stops18h 39mDelta

Deal found 10/2

$652

Tue 11/187:00 amONT - LCY

2 stops26h 05mMultiple Airlines

Tue 11/259:50 amLCY - ONT

2 stops21h 01mMultiple Airlines

Deal found 10/2

$695

One-way flights from Ontario to London
Search for one-way flight options from Ontario to London. Find affordable one-way fares based on user searches. Data last updated October 3, 2025.

Mon 11/36:00 amONT - LHR

3 stops55h 35mMultiple Airlines

Deal found 10/1

$259

Mon 11/176:53 amONT - LGW

3 stops39h 07mMultiple Airlines

Deal found 10/3

$267

Sat 10/111:37 pmONT - LGW

2 stops32h 43mMultiple Airlines

Deal found 10/2

$268

Mon 11/1710:43 pmONT - LHR

3 stops34h 47mMultiple Airlines

Deal found 10/3

$276

Sat 11/156:00 amONT - LGW

2 stops40h 00mMultiple Airlines

Deal found 10/1

$279

Mon 11/310:43 pmONT - LGW

3 stops51h 07mMultiple Airlines

Deal found 10/1

$290

Sat 10/111:37 pmONT - LHR

3 stops48h 23mMultiple Airlines

Deal found 10/2

$316

Sat 11/156:00 amONT - LHR

3 stops22h 50mMultiple Airlines

Deal found 10/1

$371

Mon 11/178:02 amONT - SEN

3 stops41h 58mMultiple Airlines

Deal found 10/3

$380

Tue 3/315:00 amONT - LHR

2 stops17h 30mAir Canada

Deal found 10/2

$391

Tue 11/43:08 pmONT - LHR

1 stop13h 07mBritish Airways

Deal found 10/3

$392

Mon 10/204:49 pmONT - LHR

1 stop12h 01mBritish Airways

Deal found 10/2

$394

Fly from

Fly to

Route

Depart

Return

Price

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Tue 12/2

1:34 pm-9:40 am

1 stop12h 06m

London Heathrow

Wed 12/10

9:30 am-9:49 pm

2 stops20h 19m

$661

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 3/4

6:00 am-10:00 am

1 stop20h 00m

London Heathrow

Tue 3/17

6:20 am-4:19 pm

2 stops16h 59m

$665

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Mon 11/10

3:08 pm-12:15 pm

1 stop13h 07m

London Heathrow

Wed 11/19

11:45 am-7:41 pm

1 stop15h 56m

$680

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 12/10

1:20 pm-10:00 am

1 stop12h 40m

London Heathrow

Wed 12/24

10:45 am-7:50 pm

1 stop17h 05m

$680

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 1/7

6:00 am-7:25 am

1 stop17h 25m

London Heathrow

Tue 2/3

12:05 pm-9:58 pm

1 stop17h 53m

$680

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Tue 11/4

10:47 am-8:35 am

1 stop13h 48m

London Heathrow

Tue 11/11

3:00 pm-10:29 pm

1 stop15h 29m

$680

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Mon 11/24

1:29 pm-9:40 am

1 stop12h 11m

London Heathrow

Wed 12/3

10:05 am-5:37 pm

1 stop15h 32m

$680

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Tue 12/9

1:20 pm-10:00 am

1 stop12h 40m

London Heathrow

Tue 12/23

10:45 am-4:12 pm

1 stop13h 27m

$680

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Tue 1/6

6:00 am-10:15 am

1 stop20h 15m

London Heathrow

Thu 1/29

10:00 am-9:58 pm

1 stop19h 58m

$680

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Sun 1/11

6:00 am-6:20 am

2 stops16h 20m

London Heathrow

Fri 1/30

12:05 pm-9:58 pm

1 stop17h 53m

$684

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/2

Showing 1-10 of 58 results

...

Compare providers for flights from Ontario to London

Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Ontario to London in October.

Provider	Price Accuracy	Trust Score*
Expedia	Price Accuracy2 stars	Trust Score*3 stars
FlightHub	Price Accuracy3 stars	Trust Score*3 stars
eDreams	Price Accuracy3 stars	Trust Score*3 stars
AranGrant	Price Accuracy3 stars	Trust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

Most accurate provider: When it comes to deals on Ontario-London flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Ontario-London flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Ontario-London flight searches over the past month and is updated monthly.
Most trusted provider: When it comes to deals on Ontario-London flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Ontario-London flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

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 round-trip 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, November is the cheapest month in which you can book a flight from Ontario to London (average of $661). Flying from Ontario to London in June is currently the most expensive (average of $1,096). 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 ONT to LON?

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

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

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

Reviews of airlines servicing London

Get a feel of what it's like to fly with Delta, United Airlines, and American Airlines from Ontario to London by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.

Delta

8.0

Very good

7,966 reviews

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

Delta

8.0

Very good

7,966 reviews

Delta

8.0

Very good

7,966 reviews

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

United Airlines

7.4

Good

8,940 reviews

Delta

8.0

Very good

7,966 reviews

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

American Airlines

7.2

Good

11,041 reviews

Delta

8.0

Very good

7,966 reviews

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

Iberia

7.0

Good

2,970 reviews

Delta

8.0

Very good

7,966 reviews

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

British Airways

6.7

Okay

7,417 reviews

Delta

8.0

Very good

7,966 reviews

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

Related info for your journey

What airport do you fly from for flights from Ontario to London?
Most people fly from Ontario (ONT) if they book a flight from Ontario to London. On average, Ontario has 0 outbound flights to London per day from 7 airlines. Ontario is conveniently located just 3.1 mi from Ontario’s city center.
How long is the flight from Ontario to London?
United Airlines, Delta, and Iberia can get you from Ontario to London in just under 12h 06m. Your travel time can differ by up to 7h 54m. Airlines will cover a distance of 5407 mi. This flight may include one or multiple stops.
What are the cheapest airlines flying from Ontario to London round-trip?
Flying on Virgin Atlantic is currently your cheapest option to London, with prices starting at $469. Additional round-trip tickets that might be worth considering are offered by Delta and KLM, with the lowest prices starting at $572 and $580, respectively. You may be able to fly from Ontario to London for 40% less than the average price by searching for these airlines.
What are the cheapest airlines to fly from Ontario to London one-way?
The cheapest airlines for a one-way flight from Ontario to London are British Airways ($395), United Airlines ($403), and Delta ($403).
What are the most popular routes from Ontario to London?
The most popular flight routes from Ontario to London are Ontario - London Heathrow, Ontario - London Gatwick and Ontario - London City.
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 vacation 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, November is the cheapest month in which you can book a flight from Ontario to London (average of $661). Flying from Ontario to London in June is currently the most expensive (average of $1,096). 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

Hounslow

Hayes

Ilford

Southend-on-Sea

Harrow

Canterbury

Croydon

Eastleigh

Dartford

Dover

Winchester

Orpington

Gatwick

Borehamwood

Aylesbury

Bedford

Chipping Norton

Wembley

Folkestone

Chichester

Browse thousands of different options on Cheapflights for your next trip

Top 7 airlines flying from Ontario to London

Airline	Cheapest	Average	Flexibility	On-time
Virgin Atlantic	Cheapest$469	Average$884	FlexibilityNo cancel fee	On-time72%
Delta	Cheapest$572	Average$677	FlexibilityNo cancel fee	On-timeN/A
KLM	Cheapest$580	Average$672	FlexibilityNo cancel fee	On-time75%
Iberia	Cheapest$615	Average$689	FlexibilityNo cancel fee	On-time77%
American Airlines	Cheapest$653	Average$959	FlexibilityNo cancel fee	On-time71%
British Airways	Cheapest$662	Average$872	FlexibilityNo cancel fee	On-time70%
United Airlines	Cheapest$677	Average$820	FlexibilityNo cancel fee	On-time69%

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$259+ Cheap flights from Ontario (ONT) to London (LON)

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 11/3. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from Ontario to London with Cheapflights

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Cheap flight deals from Ontario to London

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Find flight deals from Ontario to London

Cheapest flights from Ontario to LondonExplore 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 October 3, 2025.

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 October 3, 2025.

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

Compare providers for flights from Ontario to London

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.

Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Ontario to London in October.

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.

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?

What is the cheapest time of day to fly from ONT to LON?

Find hourly flight availability from Ontario to London. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated October 3, 2025.

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

Use this chart to determine the cheapest time to fly round-trip from Ontario to London. Price data was last updated on December 16, 2024.

Reviews of airlines servicing London

Get a feel of what it's like to fly with Delta, United Airlines, and American Airlines from Ontario to London by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.

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?

How long is the flight from Ontario to London?

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

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

What are the most popular routes from Ontario to London?

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

How can I find direct flights from Ontario to London?

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

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

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Alternative routes for Ontario to London

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Top 7 airlines flying from Ontario to London

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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 October 3, 2025.