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

£276 is the cheapest one-way deal found within the past few days, from JetBlue. You may also be able to find cheap deals on British Airways and KLM, with prices starting from £281 and £297, respectively.

In terms of precipitation, rainfall in London ranges from 40.0 - 70.0 inches per month. January is typically the wettest month, when rainfall can reach 70.0 mm. July is typically the driest time to visit London when rainfall is around 40.0 mm.

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 17.0 C. Travellers hoping to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 4.0 C).

What are the most popular routes from Ontario to London?

When deciding which route to take from Ontario to London consider Ontario - London Heathrow, Ontario - London Gatwick or Ontario - London City as they are the most popular.

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

To save up to 27% on this flight, we recommend booking at least 32 days prior to travel. The price may fluctuate and will likely increase closer to your departure date. Users on Cheapflights have found tickets from Ontario to London from £507 1-2 weeks out and tickets from £692 for flights departing within the next 72 hours.

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

Flights from Ontario to London lean towards being more expensive in December. Prices are generally better when you fly from Ontario to London in August, with the cheapest ticket starting at £336.

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

Ontario (ONT), located 3.1 mi from the city center, is the airport you fly out of when you book flights from Ontario to London. 0 airlines have flights from Ontario to London on a regular basis. Booking flights from Ontario to London should not be difficult; the airport handles an average of 0 outbound flights to London per day.

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 holiday 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.

£209+ Flights from Ontario to London

Cheap flight deals from Ontario to London

Round-trip from	£369
One-way from	£229
Popular in	December
Cheapest in	September
Average price	£559

Virgin Atlantic
1/9-10/9
2 total stops
35h 02m total
Ontario to London

Search Deals

7/9
2 total stops
28h 22m total
Ontario to London

Search Deals

Highest demand for flights based on searches. 4% potential increase in price (£23 potential increase over avg. return price).

Search Deals

Cheapest flight prices on average. 4% potential price decrease (£17 potential savings vs. average return price).

Search Deals

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

Mon 1/911:45ONT - LHR

1 stop17h 45mVirgin Atlantic

Wed 10/913:25LHR - ONT

1 stop17h 17mVirgin Atlantic

Deal found 14/8£369

Wed 1/1011:50ONT - LHR

1 stop15h 30mDelta

Thu 30/1006:20LHR - ONT

2 stops23h 21mDelta

Deal found 14/8£386

Sun 2/1111:36ONT - LHR

1 stop13h 24mKLM

Tue 18/1110:45LHR - ONT

1 stop13h 29mKLM

Deal found 14/8£387

Tue 30/1206:00ONT - LHR

2 stops17h 05mDelta

Fri 9/108:55LHR - ONT

2 stops20h 19mDelta

Deal found 14/8£389

Tue 4/1111:36ONT - LHR

1 stop13h 24mKLM

Tue 18/1110:45LHR - ONT

1 stop13h 29mKLM

Deal found 13/8£391

Tue 28/1011:48ONT - LHR

1 stop15h 42mDelta

Fri 7/1108:55LHR - ONT

1 stop18h 24mDelta

Deal found 14/8£392

Tue 28/1006:37ONT - LHR

2 stops18h 28mDelta

Tue 4/1108:50LHR - ONT

2 stops18h 29mDelta

Deal found 14/8£395

Sat 15/1112:00ONT - LHR

1 stop34h 25mDelta

Wed 3/1212:30LHR - ONT

1 stop18h 11mDelta

Deal found 14/8£395

Sun 28/907:05ONT - LHR

1 stop20h 05mVirgin Atlantic

Sun 5/1010:55LHR - ONT

1 stop20h 47mVirgin Atlantic

Deal found 14/8£406

Mon 15/906:00ONT - LHR

1 stop21h 20mDelta

Fri 26/909:00LHR - ONT

2 stops21h 23mDelta

Deal found 14/8£414

Sat 23/807:05ONT - LGW

2 stops18h 55mDelta

Sat 30/812:00LGW - ONT

2 stops30h 20mDelta

Deal found 14/8£437

Tue 19/807:00ONT - LCY

2 stops21h 30mMultiple Airlines

Tue 26/808:45LCY - ONT

2 stops21h 45mMultiple Airlines

Deal found 12/8£504

Best flights from Ontario to London
Discover carefully curated flight deals from Ontario to London that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 15 August 2025.

Mon 1/911:45ONT - LHR

1 stop17h 45mVirgin Atlantic

Wed 10/913:25LHR - ONT

1 stop17h 17mVirgin Atlantic

Deal found 14/8£369

Tue 30/1206:45ONT - LHR

1 stop22h 05mDelta

Fri 9/108:55LHR - ONT

2 stops20h 19mDelta

Deal found 14/8£386

Sun 2/1111:36ONT - LHR

1 stop13h 24mKLM

Tue 18/1110:45LHR - ONT

1 stop13h 29mKLM

Deal found 14/8£387

Thu 11/908:15ONT - LGW

2 stops18h 25mAmerican Airlines

Tue 16/912:20LGW - ONT

2 stops18h 13mAmerican Airlines

Deal found 12/8£489

Wed 5/1107:00ONT - LCY

2 stops21h 50mMultiple Airlines

Tue 11/1109:50LCY - ONT

2 stops19h 47mMultiple Airlines

Deal found 13/8£504

Sat 7/210:57ONT - LGW

2 stops39h 53mIberia

Wed 25/219:40LGW - ONT

2 stops26h 04mIberia

Deal found 12/8£513

Wed 5/1111:36ONT - LHR

1 stop13h 24mDelta

Tue 11/1106:20LHR - ONT

2 stops21h 22mDelta

Deal found 13/8£386

Wed 1/1011:50ONT - LHR

1 stop18h 25mDelta

Thu 30/1006:20LHR - ONT

2 stops23h 21mDelta

Deal found 13/8£386

Wed 10/907:05ONT - LHR

2 stops19h 10mDelta

Tue 16/906:15LHR - ONT

2 stops21h 00mDelta

Deal found 13/8£389

Tue 18/1107:00ONT - LGW

2 stops19h 50mIberia

Tue 2/1211:45LGW - ONT

2 stops55h 45mIberia

Deal found 14/8£521

Thu 18/908:15ONT - LGW

2 stops16h 20mAmerican Airlines

Tue 23/914:30LGW - ONT

2 stops29h 27mAmerican Airlines

Deal found 12/8£529

Sat 22/1112:53ONT - LGW

2 stops37h 57mIberia

Wed 3/1211:45LGW - ONT

2 stops31h 45mIberia

Deal found 13/8£587

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

Tue 19/808:00ONT - LGW

1 stop17h 20mMultiple Airlines

Tue 26/810:25LGW - ONT

1 stop13h 53mMultiple Airlines

Deal found 12/8£712

Tue 19/807:05ONT - LGW

2 stops18h 55mKLM

Sun 31/812:00LGW - ONT

2 stops39h 11mKLM

Deal found 13/8£720

Tue 19/807:00ONT - LCY

2 stops21h 30mMultiple Airlines

Tue 26/808:45LCY - ONT

2 stops21h 45mMultiple Airlines

Deal found 12/8£504

Wed 20/810:50ONT - LHR

1 stop14h 10mBritish Airways

Mon 25/816:15LHR - ONT

2 stops38h 33mBritish Airways

Deal found 14/8£465

Wed 20/813:42ONT - LHR

1 stop12h 43mUnited Airlines

Thu 18/911:25LHR - ONT

1 stop14h 04mUnited Airlines

Deal found 13/8£479

Wed 20/815:04ONT - LGW

2 stops15h 36mMultiple Airlines

Sun 7/913:00LGW - ONT

2 stops18h 45mMultiple Airlines

Deal found 12/8£4,748

Thu 21/811:45ONT - LHR

1 stop17h 45mDelta

Thu 28/806:15LHR - ONT

2 stops24h 27mDelta

Deal found 14/8£423

Thu 21/811:45ONT - LHR

1 stop17h 45mKLM

Thu 28/809:20LHR - ONT

1 stop17h 51mKLM

Deal found 14/8£428

Fri 22/813:15ONT - LHR

2 stops15h 55mDelta

Thu 28/811:20LHR - ONT

1 stop15h 51mDelta

Deal found 14/8£431

Fri 22/814:57ONT - LHR

1 stop15h 28mBritish Airways

Thu 28/816:25LHR - ONT

1 stop15h 43mBritish Airways

Deal found 14/8£512

Sat 23/807:05ONT - LGW

2 stops18h 55mDelta

Sat 30/812:00LGW - ONT

2 stops30h 20mDelta

Deal found 14/8£437

Sat 23/813:15ONT - LHR

1 stop12h 35mDelta

Sat 30/811:30LHR - ONT

2 stops19h 12mDelta

Deal found 14/8£459

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 15 August 2025.

Sun 7/922:28ONT - LGW

2 stops28h 22mMultiple Airlines

Deal found 12/8£229

Sat 27/922:56ONT - LHR

1 stop13h 49mJetBlue

Deal found 14/8£276

Wed 19/1116:47ONT - LHR

1 stop12h 28mBritish Airways

Deal found 13/8£281

Mon 13/1016:49ONT - LHR

1 stop12h 01mBritish Airways

Deal found 13/8£282

Sun 12/1016:49ONT - LHR

1 stop12h 01mBritish Airways

Deal found 12/8£284

Mon 20/1016:49ONT - LHR

1 stop12h 01mBritish Airways

Deal found 14/8£285

Tue 16/922:56ONT - LHR

1 stop13h 49mJetBlue

Deal found 14/8£286

Mon 25/813:15ONT - LHR

1 stop12h 35mVirgin Atlantic

Deal found 14/8£288

Fri 5/922:56ONT - LHR

1 stop13h 49mJetBlue

Deal found 14/8£290

Sun 21/913:15ONT - LHR

1 stop12h 25mUnited Airlines

Deal found 13/8£291

Fri 12/922:56ONT - LHR

1 stop13h 49mJetBlue

Deal found 13/8£292

Tue 9/906:00ONT - LHR

2 stops19h 35mAir Canada

Deal found 14/8£293

Fly from

Fly to

Route

Depart

Return

Price

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Mon 1/9

11:45-13:30

1 stop17h 45m

London Heathrow

Wed 10/9

13:25-22:42

1 stop17h 17m

£369

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Tue 30/12

06:45-12:50

1 stop22h 05m

London Heathrow

Fri 9/1

08:55-21:14

2 stops20h 19m

£386

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 5/11

11:36-09:00

1 stop13h 24m

London Heathrow

Tue 11/11

06:20-19:42

2 stops21h 22m

£386

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 1/10

11:50-14:15

1 stop18h 25m

London Heathrow

Thu 30/10

06:20-22:41

2 stops23h 21m

£386

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Sun 2/11

11:36-09:00

1 stop13h 24m

London Heathrow

Tue 18/11

10:45-16:14

1 stop13h 29m

£387

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 10/9

07:05-10:15

2 stops19h 10m

London Heathrow

Tue 16/9

06:15-19:15

2 stops21h 00m

£389

OntarioLondon

ONT - LGW

ONTLGW

Ontario

Thu 11/9

08:15-10:40

2 stops18h 25m

London Gatwick

Tue 16/9

12:20-22:33

2 stops18h 13m

£489

OntarioLondon

ONT - LCY

ONTLCY

Ontario

Wed 5/11

07:00-12:50

2 stops21h 50m

London City

Tue 11/11

09:50-21:37

2 stops19h 47m

£504

OntarioLondon

ONT - LGW

ONTLGW

Ontario

Sat 7/2

10:57-10:50

2 stops39h 53m

London Gatwick

Wed 25/2

19:40-13:44

2 stops26h 04m

£513

OntarioLondon

ONT - LGW

ONTLGW

Ontario

Tue 18/11

07:00-10:50

2 stops19h 50m

London Gatwick

Tue 2/12

11:45-11:30

2 stops55h 45m

£521

Flights are sorted by cheapest return flights first.

Deals found on 12/8

Showing 1-10 of 54 results

...

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 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 Ontario to London

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

Currently, January is the cheapest month in which you can book a flight from Ontario to London (average of £112). Flying from Ontario to London in August is currently the most expensive (average of £164). 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?

One of the essential ways to save on airfare from Ontario to London is to remain as flexible as possible. Flights that are in the morning tend to be the most expensive. A flight at midday could potentially save you up to 19% on airfare.

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

Dallas (DFW) – chosen by Cheapflights users on 67% of one-stop itineraries from Ontario to London on Cheapflights.

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

Phoenix (PHX) is the most affordable one-stop option, with an average return flight price of £468.

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

Flights via Phoenix (PHX) have the shortest average one-way travel time for one-stop routes: 12h 15m.

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

Flights via Phoenix (PHX) offer the fastest connection on this route, with an average stopover time of 1h 28m.

Related info for your journey

What airport do you fly from for flights from Ontario to London?
Ontario (ONT), located 3.1 mi from the city center, is the airport you fly out of when you book flights from Ontario to London. 0 airlines have flights from Ontario to London on a regular basis. Booking flights from Ontario to London should not be difficult; the airport handles an average of 0 outbound flights to London per day.
What are the cheapest airlines to fly from Ontario to London one-way?
£276 is the cheapest one-way deal found within the past few days, from JetBlue. You may also be able to find cheap deals on British Airways and KLM, with prices starting from £281 and £297, respectively.
What are the most popular routes from Ontario to London?
When deciding which route to take from Ontario to London consider Ontario - London Heathrow, Ontario - London Gatwick or Ontario - London City as they are the most popular.
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 holiday 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, January is the cheapest month in which you can book a flight from Ontario to London (average of £112). Flying from Ontario to London in August is currently the most expensive (average of £164). 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

Milton Keynes

Croydon

Hounslow

Gatwick

Slough

Deal

Luton

Wembley

Crawley

Ilford

Hayes

Ipswich

Southend-on-Sea

Winchester

Folkestone

Eastbourne

Maidstone

Watford

Chichester

Dartford

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How does Cheapflights help users find flights from Ontario to London?

Cheapflights helps you search for flights from Ontario to London via 900+ travel sites so you don’t have to. After performing a flight search, users can also filter their flight selection by filtering for price, number of stops, airlines, and so on.

Why should you use Cheapflights to find cheap flight tickets from Ontario to London?

Cheapflights taps into our reliable network of hundreds of airlines and travel agencies to find the best deals for flights from Ontario to London for you. Better yet — we are completely free to use.

Can Cheapflights find flights from Ontario to London with no change fees?

Yes! Cheapflights helps users easily find flights from Ontario to London with no change fees.

Can Cheapflights notify me if prices for flights from Ontario to London become cheaper?

Yes! Start tracking prices for Ontario to London flights today and get alerted whenever prices for these flights change. To access this feature, click the bell icon next to the flight deals above, which will prompt you for a valid email address to receive your alerts.

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Cheap flights from Ontario to London from £209

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 11/9. Fares are subject to change and may not be available on all flights or dates of travel.

Cheap flight deals from Ontario to London

Round-trip from

One-way from

Popular in

Cheapest in

Average price

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 15 August 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 15 August 2025.

Cheapflights Fare Finder

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

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 15 August 2025.

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

Share of one-stop return flights from Ontario to London chosen by Cheapflights users in the past 12 months, using the same stopover each way.

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

Average return fare for one-stop flights from Ontario to London, chosen by Cheapflights users in the past 12 months, with the same stopover each way.

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

Shortest average travel time for one-stop one-way flights from Ontario to London, 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 Ontario to London?

Average stopover duration for one-stop one-way flights from Ontario to London, chosen by Cheapflights users in the last 12 months, grouped by stopover airport.

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?

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?

Travelling to a place near London?

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Alternative routes for Ontario to London

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How does Cheapflights help users find flights from Ontario to London?

Why should you use Cheapflights to find cheap flight tickets from Ontario to London?

Can Cheapflights find flights from Ontario to London with no change fees?

Can Cheapflights notify me if prices for flights from Ontario to London become cheaper?

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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 15 August 2025.