How long is the flight from Ontario to London?

Delta, KLM, and Iberia can get you from Ontario to London in just under 13h 15m. Your travel time can differ by up to 7h 25m. 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 Delta is currently your cheapest option to London, with prices starting at $570. Additional round-trip tickets that might be worth considering are offered by KLM and Iberia, with the lowest prices starting at $580 and $615, respectively. You may be able to fly from Ontario to London for 27% less than the average price by searching for these airlines.

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: United Airlines, British Airways or American Airlines.

Most accurate provider : When it comes to deals on Ontario-London flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Ontario-London flight deals on Cheapflights vs. eDreams >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 eDreams the most. eDreams 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 6 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.

$290+ Flights from Ontario to London

Home Search by date Vacation packages Hotels Flight deals Car rental Travel tips & news

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

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 diciembre 4, 2025.

mié. 12/101:29 pmONT - LHR

1 stop12h 31mDelta

mar. 12/2310:45 amLHR - ONT

1 stop21h 09mDelta

Deal found 12/3

$598

mié. 12/101:34 pmONT - LHR

1 stop12h 06mUnited Airlines

vie. 1/910:00 amLHR - ONT

1 stop19h 58mUnited Airlines

Deal found 12/3

$647

mar. 12/91:34 pmONT - LHR

1 stop12h 06mUnited Airlines

mar. 12/1610:05 amLHR - ONT

1 stop15h 32mUnited Airlines

Deal found 12/2

$648

jue. 12/1110:47 amONT - LHR

1 stop15h 13mBritish Airways

lun. 12/157:05 pmLHR - ONT

2 stops26h 50mBritish Airways

Deal found 12/3

$657

mié. 12/107:00 amONT - LHR

1 stop19h 00mIberia

dom. 4/121:00 pmLHR - ONT

1 stop18h 40mIberia

Deal found 12/2

$662

jue. 12/111:34 pmONT - LHR

1 stop12h 06mUnited Airlines

jue. 12/1810:05 amLHR - ONT

1 stop15h 38mUnited Airlines

Deal found 12/3

$674

jue. 12/116:40 amONT - LHR

1 stop22h 10mDelta

lun. 12/152:45 pmLHR - ONT

1 stop16h 02mDelta

Deal found 12/4

$698

jue. 12/111:50 pmONT - LHR

1 stop14h 10mUnited Airlines

lun. 12/221:45 pmLHR - ONT

1 stop16h 56mUnited Airlines

Deal found 12/2

$699

mié. 12/101:34 pmONT - LHR

1 stop12h 06mUnited Airlines

vie. 12/2610:05 amLHR - ONT

1 stop15h 38mUnited Airlines

Deal found 12/2

$703

mar. 12/166:00 amONT - LHR

1 stop17h 30mUnited Airlines

vie. 1/93:10 pmLHR - ONT

2 stops29h 07mUnited Airlines

Deal found 12/3

$706

jue. 12/1112:40 pmONT - LHR

1 stop13h 50mDelta

lun. 4/1311:20 amLHR - ONT

1 stop13h 56mDelta

Deal found 12/2

$712

mar. 12/97:00 amONT - LGW

2 stops19h 50mIberia

mié. 4/158:40 pmLGW - ONT

2 stops35h 00mIberia

Deal found 12/2

$967

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 diciembre 4, 2025.

mar. 1/133:30 pmONT - LHR

2 stops20h 40mDelta

mar. 1/206:20 amLHR - ONT

2 stops24h 31mDelta

Deal found 12/2

$603

mié. 3/1812:45 pmONT - LHR

1 stop13h 15mKLM

mié. 3/2512:10 pmLHR - ONT

1 stop15h 54mKLM

Deal found 12/3

$605

lun. 1/56:39 pmONT - LHR

2 stops55h 01mUnited Airlines

mar. 1/209:30 amLHR - ONT

2 stops20h 29mUnited Airlines

Deal found 12/3

$627

vie. 1/306:00 amONT - LHR

2 stops16h 50mVirgin Atlantic

mar. 2/311:45 amLHR - ONT

2 stops42h 59mVirgin Atlantic

Deal found 12/1

$629

mié. 1/2110:58 amONT - LCY

2 stops19h 07mIberia

jue. 1/297:50 amLCY - ONT

2 stops22h 58mIberia

Deal found 12/3

$740

mié. 1/286:22 amONT - LGW

2 stops18h 38mAmerican Airlines

dom. 2/111:20 amLGW - ONT

2 stops56h 43mAmerican Airlines

Deal found 12/1

$807

mar. 3/107:00 amONT - LCY

2 stops18h 50mMultiple Airlines

mar. 3/176:15 pmLCY - ONT

2 stops35h 21mMultiple Airlines

Deal found 12/2

$890

mié. 1/216:00 amONT - LHR

2 stops19h 00mDelta

dom. 1/258:40 amLHR - ONT

2 stops20h 25mDelta

Deal found 12/2

$607

mié. 4/811:59 amONT - LHR

1 stop18h 16mKLM

mié. 4/1510:55 amLHR - ONT

1 stop20h 49mKLM

Deal found 12/2

$620

dom. 1/181:24 pmONT - LHR

1 stop12h 16mUnited Airlines

dom. 1/259:30 amLHR - ONT

2 stops20h 28mUnited Airlines

Deal found 12/3

$636

mié. 4/1511:55 amONT - LHR

1 stop18h 20mDelta

mar. 5/56:15 amLHR - ONT

2 stops19h 01mDelta

Deal found 12/3

$614

vie. 5/1511:59 pmONT - LCY

2 stops34h 26mBritish Airways

lun. 5/187:00 pmLCY - ONT

2 stops34h 56mBritish Airways

Deal found 12/2

$1,363

lun. 4/206:00 amONT - LHR

1 stop19h 50mKLM

jue. 5/711:20 amLHR - ONT

1 stop19h 20mKLM

Deal found 12/3

$620

lun. 4/2012:00 pmONT - LHR

1 stop17h 30mDelta

jue. 5/76:15 amLHR - ONT

2 stops19h 01mDelta

Deal found 12/3

$614

jue. 2/56:00 amONT - LGW

2 stops20h 50mIberia

lun. 2/97:40 pmLGW - ONT

2 stops26h 38mIberia

Deal found 12/2

$787

lun. 5/412:00 pmONT - LHR

1 stop17h 30mDelta

jue. 5/2110:55 amLHR - ONT

1 stop15h 20mDelta

Deal found 12/2

$620

jue. 2/56:00 amONT - LCY

2 stops18h 50mIberia

lun. 2/97:15 pmLCY - ONT

2 stops22h 53mIberia

Deal found 12/2

$815

mié. 3/46:14 amONT - LGW

2 stops20h 41mMultiple Airlines

dom. 3/811:55 amLGW - ONT

2 stops18h 37mMultiple Airlines

Deal found 12/4

$976

jue. 3/57:10 amONT - LCY

2 stops17h 40mIberia

jue. 3/127:50 amLCY - ONT

2 stops21h 40mIberia

Deal found 12/3

$840

mié. 4/156:00 amONT - LGW

2 stops24h 40mMultiple Airlines

mar. 5/51:00 pmLGW - ONT

2 stops17h 38mMultiple Airlines

Deal found 12/2

$979

mié. 1/216:30 amONT - LGW

2 stops20h 25mMultiple Airlines

jue. 1/2911:55 amLGW - ONT

2 stops20h 01mMultiple Airlines

Deal found 12/3

$1,010

jue. 2/127:10 amONT - LCY

2 stops17h 40mIberia

lun. 2/167:15 pmLCY - ONT

2 stops22h 52mIberia

Deal found 12/3

$943

jue. 3/56:14 amONT - LGW

2 stops20h 41mMultiple Airlines

jue. 3/1211:55 amLGW - ONT

2 stops18h 37mMultiple Airlines

Deal found 12/2

$1,036

jue. 3/57:10 amONT - LCY

2 stops17h 40mIberia

lun. 3/237:15 pmLCY - ONT

2 stops21h 51mIberia

Deal found 12/2

$965

sáb. 4/253:05 pmONT - LGW

2 stops35h 50mIberia

jue. 5/711:35 amLGW - ONT

2 stops20h 05mIberia

Deal found 12/2

$1,010

mié. 3/1810:57 amONT - LCY

2 stops20h 08mIberia

mié. 3/257:50 amLCY - ONT

2 stops23h 09mIberia

Deal found 12/2

$1,029

lun. 3/910:57 amONT - LCY

2 stops20h 38mIberia

vie. 3/137:50 amLCY - ONT

2 stops23h 09mIberia

Deal found 12/3

$1,136

jue. 3/127:00 amONT - LCY

2 stops18h 50mIberia

mié. 3/187:50 amLCY - ONT

2 stops21h 40mIberia

Deal found 12/2

$1,290

Last-minute flights from Ontario to London
Discover last-minute flight deals from Ontario to London. Data last updated diciembre 4, 2025 and is based on user searches.

mié. 12/101:29 pmONT - LHR

1 stop12h 31mDelta

jue. 12/258:55 amLHR - ONT

1 stop18h 55mDelta

Deal found 12/3

$598

lun. 1/56:39 pmONT - LHR

2 stops55h 01mUnited Airlines

mar. 1/209:30 amLHR - ONT

2 stops20h 29mUnited Airlines

Deal found 12/3

$627

mar. 1/610:30 pmONT - LHR

2 stops24h 35mDelta

mar. 1/1310:45 amLHR - ONT

1 stop18h 20mDelta

Deal found 12/2

$609

mar. 1/1310:58 amONT - LHR

1 stop13h 37mBritish Airways

mar. 1/206:00 amLHR - ONT

2 stops20h 45mBritish Airways

Deal found 12/2

$584

mar. 1/133:30 pmONT - LHR

2 stops20h 40mDelta

mar. 1/206:20 amLHR - ONT

2 stops24h 31mDelta

Deal found 12/2

$603

vie. 1/166:00 amONT - LHR

1 stop20h 00mVirgin Atlantic

vie. 1/236:20 amLHR - ONT

2 stops24h 31mVirgin Atlantic

Deal found 12/2

$623

mié. 1/2110:58 amONT - LHR

1 stop15h 02mIberia

jue. 1/297:30 amLHR - ONT

2 stops23h 18mIberia

Deal found 12/3

$577

mié. 1/2110:58 amONT - LHR

1 stop16h 42mIberia

dom. 1/257:30 amLHR - ONT

2 stops23h 18mIberia

Deal found 12/2

$602

mié. 1/2112:41 pmONT - LHR

1 stop14h 59mDelta

mié. 2/412:30 pmLHR - ONT

1 stop16h 35mDelta

Deal found 12/3

$605

mié. 1/216:00 amONT - LHR

2 stops19h 00mDelta

dom. 1/258:40 amLHR - ONT

2 stops20h 25mDelta

Deal found 12/2

$607

mié. 1/2110:58 amONT - LCY

2 stops19h 07mIberia

jue. 1/297:50 amLCY - ONT

2 stops22h 58mIberia

Deal found 12/3

$740

vie. 1/306:00 amONT - LHR

1 stop20h 00mVirgin Atlantic

mar. 2/311:45 amLHR - ONT

2 stops42h 59mVirgin Atlantic

Deal found 12/1

$625

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 diciembre 4, 2025.

sáb. 1/177:15 amONT - LGW

3 stops38h 45mMultiple Airlines

Deal found 12/3

$290

sáb. 1/179:10 pmONT - LHR

2 stops55h 40mMultiple Airlines

Deal found 12/3

$304

lun. 1/264:45 pmONT - LHR

1 stop12h 30mBritish Airways

Deal found 12/3

$366

lun. 2/94:45 pmONT - LHR

1 stop12h 30mBritish Airways

Deal found 12/2

$371

dom. 2/155:06 pmONT - LHR

1 stop12h 09mBritish Airways

Deal found 12/3

$373

mié. 12/106:00 amONT - LHR

1 stop17h 30mUnited Airlines

Deal found 12/3

$374

mar. 1/131:11 pmONT - LHR

1 stop12h 49mVirgin Atlantic

Deal found 12/2

$376

mié. 12/1010:47 amONT - LHR

1 stop15h 13mIberia

Deal found 12/3

$380

mié. 12/315:05 amONT - LHR

2 stops18h 05mAir Canada

Deal found 12/3

$382

mar. 12/305:05 amONT - LHR

2 stops22h 15mAir Canada

Deal found 12/3

$385

sáb. 1/171:53 pmONT - LHR

1 stop33h 32mUnited Airlines

Deal found 12/2

$391

sáb. 1/177:15 amONT - LCY

3 stops49h 55mMultiple Airlines

Deal found 12/3

$412

Find flight deals from Ontario to London

Most accurate provider	eDreams 3 stars
Most trusted provider	eDreams 3 stars
Round-trip from	$575 (Iberia)
One-way from	$290 (Kiwi.com)
Popular in	June
Cheapest in	October
Average price	$752

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. 14% potential increase in price ($130 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 3% potential price decrease ($26 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in December 2025

Search Deals

Fly from

Fly to

Route

Depart

Return

Price

OntarioLondon

ONT - LHR

ONTLHR

Ontario

mar. 1/13

3:30 pm-8:10 pm

2 stops20h 40m

London Heathrow

mar. 1/20

6:20 am-10:51 pm

2 stops24h 31m

$603

OntarioLondon

ONT - LHR

ONTLHR

Ontario

mié. 3/18

12:45 pm-9:00 am

1 stop13h 15m

London Heathrow

mié. 3/25

12:10 pm-9:04 pm

1 stop15h 54m

$605

OntarioLondon

ONT - LHR

ONTLHR

Ontario

mié. 1/21

6:00 am-9:00 am

2 stops19h 00m

London Heathrow

dom. 1/25

8:40 am-9:05 pm

2 stops20h 25m

$607

OntarioLondon

ONT - LHR

ONTLHR

Ontario

mié. 4/15

11:55 am-2:15 pm

1 stop18h 20m

London Heathrow

mar. 5/5

6:15 am-5:16 pm

2 stops19h 01m

$614

OntarioLondon

ONT - LHR

ONTLHR

Ontario

lun. 4/20

12:00 pm-1:30 pm

1 stop17h 30m

London Heathrow

jue. 5/7

6:15 am-5:16 pm

2 stops19h 01m

$614

OntarioLondon

ONT - LHR

ONTLHR

Ontario

mié. 4/8

11:59 am-2:15 pm

1 stop18h 16m

London Heathrow

mié. 4/15

10:55 am-11:44 pm

1 stop20h 49m

$620

OntarioLondon

ONT - LHR

ONTLHR

Ontario

lun. 4/20

6:00 am-9:50 am

1 stop19h 50m

London Heathrow

jue. 5/7

11:20 am-10:40 pm

1 stop19h 20m

$620

OntarioLondon

ONT - LHR

ONTLHR

Ontario

lun. 5/4

12:00 pm-1:30 pm

1 stop17h 30m

London Heathrow

jue. 5/21

10:55 am-6:15 pm

1 stop15h 20m

$620

OntarioLondon

ONT - LHR

ONTLHR

Ontario

lun. 1/5

6:39 pm-9:40 am

2 stops55h 01m

London Heathrow

mar. 1/20

9:30 am-9:59 pm

2 stops20h 29m

$627

OntarioLondon

ONT - LHR

ONTLHR

Ontario

vie. 1/30

6:00 am-6:50 am

2 stops16h 50m

London Heathrow

mar. 2/3

11:45 am-10:44 pm

2 stops42h 59m

$629

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/3

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 December.

Provider	Price Accuracy	Trust Score*
Expedia	Price Accuracy2 stars	Trust Score*3 stars
FlightHub	Price Accuracy3 stars	Trust Score*1 star
eDreams	Price Accuracy3 stars	Trust Score*3 stars
AranGrant	Price Accuracy2 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 eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Ontario-London flight deals on Cheapflights vs. eDreams >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 eDreams the most. eDreams 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, October is the cheapest month in which you can book a flight from Ontario to London (average of $226). Flying from Ontario to London in June is currently the most expensive (average of $563). 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 afternoon. By choosing this option you can save up to 37% on the cost of your flight, compared to a flight at noon.

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 mornings 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

7.9

Good

8,011 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

7.9

Good

8,011 reviews

Delta

7.9

Good

8,011 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

9,063 reviews

Delta

7.9

Good

8,011 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

11,043 reviews

Delta

7.9

Good

8,011 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

3,039 reviews

Delta

7.9

Good

8,011 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

7,559 reviews

Delta

7.9

Good

8,011 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 6 airlines. Ontario is conveniently located just 3.1 mi from Ontario’s city center.
How long is the flight from Ontario to London?
Delta, KLM, and Iberia can get you from Ontario to London in just under 13h 15m. Your travel time can differ by up to 7h 25m. 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 Delta is currently your cheapest option to London, with prices starting at $570. Additional round-trip tickets that might be worth considering are offered by KLM and Iberia, with the lowest prices starting at $580 and $615, respectively. You may be able to fly from Ontario to London for 27% less than the average price by searching for these airlines.
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, October is the cheapest month in which you can book a flight from Ontario to London (average of $226). Flying from Ontario to London in June is currently the most expensive (average of $563). 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

Ilford

Hounslow

Hayes

Southend-on-Sea

Harrow

Eastleigh

Dartford

Dover

Winchester

Croydon

Orpington

Watford

Borehamwood

Aylesbury

Chipping Norton

Kingston upon Thames

Wembley

Folkestone

Eastbourne

Sutton

Browse thousands of different options on Cheapflights for your next trip

Top 6 airlines flying from Ontario to London

Airline	Cheapest	Average	Flexibility	On-time
Delta	Cheapest$570	Average$672	FlexibilityNo cancel fee	On-timeN/A
KLM	Cheapest$580	Average$672	FlexibilityNo cancel fee	On-time75%
Iberia	Cheapest$615	Average$728	FlexibilityNo cancel fee	On-time77%
American Airlines	Cheapest$624	Average$795	FlexibilityNo cancel fee	On-time71%
British Airways	Cheapest$653	Average$862	FlexibilityNo cancel fee	On-time70%
United Airlines	Cheapest$665	Average$810	FlexibilityNo cancel fee	On-time69%

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

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.

$290+ 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 1/17. 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

1. Tell us where you want to go

2. Select your favorite providers

3. Compare prices and book

Cheap 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 diciembre 4, 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 diciembre 4, 2025.

Find flight deals from Ontario to London

Most accurate provider

Most trusted provider

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Cheapflights Fare Finder

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 December.

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 diciembre 4, 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 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?

Traveling to a place near London?

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Ontario to London

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

Top 6 airlines flying from Ontario to London

100% Free

Book with Flexibility

Travel Smart

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 diciembre 4, 2025.