Cheap flights from Ontario (ONT) to London (LON) from $288

This is the cheapest one-way flight price, found on 10/3. Prices may vary by date and flight preferences.
ONT — LON
Oct 8 — Oct 151

How to find the cheapest flight from Ontario (ONT) to London (LON)

All the information you need to plan the best ONT to LON flight in 2023: compare Ontario to London flight prices with the expected peak season, weather and rainfall in London.

Popular in

December

Cheapest in

February

Round-trip from

$617

One-way from

$561
High demand for flights, 26% potential price rise
Best time to find cheap flights, 25% potential price drop
From Ontario to London (LON)
One-way flight from Ontario to London (LON)

ONT - LON

Price

$617 - $1,178

LON

Temperature

39.2 - 62.6 °F

LON

Rainfall

1.6 - 2.8 inches

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

Saturday flights are found to be more expensive to fly from Ontario to London. This shouldn’t discourage you from searching, as you can still find great deals by being flexible with your options. Use our search form to find deals on tickets to London.

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

To save on the cost of your flight from Ontario to London, book at least 61 days before your planned departure. Booking around this time can save you about 33% on the cost of this flight compared to booking a flight leaving this week. We have found prices from $1,103 if you need a flight within two weeks. For flights within the next 72 hours, you can find tickets from as low as $1,332.

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

Our data shows that February tends to be the cheapest month to fly to London from Ontario. Users have commonly found prices around $892 for the month, but tickets can be as low as $573. Due to multiple factors, prepare for potentially higher prices in July.

When is the cheapest time to fly from Ontario to London (ONT - LON)?

It’s optimal to fly from Ontario to London in the afternoon. By choosing this option you can save up to 16% on the cost of your flight, compared to a flight in the evening.

Cheap British Airways flights from Ontario to London

Check out some of the cheapest British Airways flights we've come across from Ontario to London. Make sure to check back often as deals are often changing.

Cheap American Airlines flights from Ontario to London

Some of the best deals we've found on American Airlines flights traveling from Ontario to London. Ensure the flight price, dates, time, and airline match your criteria before you book.

Cheap Ontario to London flights in October & November 2023

The best prices found for ONT to LON flights for October, November
Listed are some of the best fares we've found on flights departing from Ontario to London in 2023. For more flight deals, be sure to check back very soon.

Ontario to London 2023 flight deals

Cheap flights to London from Ontario found for this year
Listed are some of the best fares we've found on flights departing from Ontario to London in 2023. For more flight deals, be sure to check back very soon.

Ontario to London flights leaving soon

Late deals on return flights to London from Ontario, departing today and this week
Consider one of these great deals we found on last-minute flights from Ontario to London. Users should examine the flight details to ensure there are no surprises.

One-way flights to London from Ontario

The cheapest one-way flights from Ontario to London
Users in need of a one-way flight from Ontario to London can choose from these deals. Those seeking round-trip flights from Ontario to London should utilize the search form at the the top of the page.

Find flights from Ontario to London within your budget

Use the slider to find flights from Ontario to London that fit your budget.

Fly from

Any airport

Fly to

Any airport

Budget

$593 - $680

Route

Depart

Return

Price

OntarioLondon Gatwick

ONT - LGW

ONTLGW

Ontario

Sat 10/21

2 stops20h 55m

London Gatwick

Sat 10/28

2 stops34h 20m

OntarioLondon Heathrow

ONT - LHR

ONTLHR

Ontario

Sat 10/21

1 stop15h 05m

London Heathrow

Sat 10/28

1 stop15h 28m

OntarioLondon Heathrow

ONT - LHR

ONTLHR

Ontario

Wed 10/18

1 stop17h 00m

London Heathrow

Thu 10/26

1 stop17h 03m

OntarioLondon Heathrow

ONT - LHR

ONTLHR

Ontario

Wed 10/18

1 stop12h 53m

London Heathrow

Thu 10/26

2 stops20h 24m

OntarioLondon Heathrow

ONT - LHR

ONTLHR

Ontario

Thu 1/18

2 stops17h 40m

London Heathrow

Tue 1/23

2 stops29h 43m

OntarioLondon Heathrow

ONT - LHR

ONTLHR

Ontario

Wed 10/18

1 stop19h 14m

London Heathrow

Mon 10/30

1 stop17h 29m

OntarioLondon Heathrow

ONT - LHR

ONTLHR

Ontario

Fri 10/20

1 stop22h 46m

London Heathrow

Sat 10/28

1 stop19h 28m

OntarioLondon Heathrow

ONT - LHR

ONTLHR

Ontario

Wed 10/18

1 stop13h 39m

London Heathrow

Sat 10/28

1 stop17h 22m

OntarioLondon Heathrow

ONT - LHR

ONTLHR

Ontario

Wed 11/1

2 stops22h 50m

London Heathrow

Mon 11/13

2 stops18h 24m

Flights are sorted by cheapest first

Deals found on 10/3

Reviews of airlines servicing London

Get a feel of what it's like to fly with British Airways, American Airlines and JetBlue from Ontario to London by reading reviews from past customers. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.1
Very good
1,394 reviews

Entertainment

7.2

Comfort

8.0

Overall

8.1

Boarding

8.3

Crew

8.6

Food

7.2

Reviews

1 / 10

Due to gate changes and poor announcing, I was unable to board my flight to Missoula. I received no refund. As a person who flies 3-5 times a year, god willing for another 40 years or so, I will strive to never fly Alaska Airlines again.

Alaska Airlines
8.1
Very good
1,394 reviews
Alaska Airlines
8.1
Very good
1,394 reviews

Entertainment

7.2

Comfort

8.0

Overall

8.1

Boarding

8.3

Crew

8.6

Food

7.2

Reviews

1 / 10

Due to gate changes and poor announcing, I was unable to board my flight to Missoula. I received no refund. As a person who flies 3-5 times a year, god willing for another 40 years or so, I will strive to never fly Alaska Airlines again.

Delta
7.9
Good
3,023 reviews
Alaska Airlines
8.1
Very good
1,394 reviews

Entertainment

7.2

Comfort

8.0

Overall

8.1

Boarding

8.3

Crew

8.6

Food

7.2

Reviews

1 / 10

Due to gate changes and poor announcing, I was unable to board my flight to Missoula. I received no refund. As a person who flies 3-5 times a year, god willing for another 40 years or so, I will strive to never fly Alaska Airlines again.

Air France
7.6
Good
274 reviews
Alaska Airlines
8.1
Very good
1,394 reviews

Entertainment

7.2

Comfort

8.0

Overall

8.1

Boarding

8.3

Crew

8.6

Food

7.2

Reviews

1 / 10

Due to gate changes and poor announcing, I was unable to board my flight to Missoula. I received no refund. As a person who flies 3-5 times a year, god willing for another 40 years or so, I will strive to never fly Alaska Airlines again.

KLM
7.5
Good
196 reviews
Alaska Airlines
8.1
Very good
1,394 reviews

Entertainment

7.2

Comfort

8.0

Overall

8.1

Boarding

8.3

Crew

8.6

Food

7.2

Reviews

1 / 10

Due to gate changes and poor announcing, I was unable to board my flight to Missoula. I received no refund. As a person who flies 3-5 times a year, god willing for another 40 years or so, I will strive to never fly Alaska Airlines again.

United Airlines
7.4
Good
1,891 reviews
Alaska Airlines
8.1
Very good
1,394 reviews

Entertainment

7.2

Comfort

8.0

Overall

8.1

Boarding

8.3

Crew

8.6

Food

7.2

Reviews

1 / 10

Due to gate changes and poor announcing, I was unable to board my flight to Missoula. I received no refund. As a person who flies 3-5 times a year, god willing for another 40 years or so, I will strive to never fly Alaska Airlines again.

Related info for your journey

Useful info, stats and facts about Ontario to London flights.

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 flights from Ontario to London for under $600 on Cheapflights?

Yes, there are multiple flights from Ontario to London for under $600. The cheapest flight booked recently is on KLM for just $593, but on average you can expect to pay $634.

Are there last-minute flights available from Ontario to London for under $1,300?

There are currently 20+ open flights from Ontario to London within the next 7 days for less than $1,300.

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

Flying on KLM is currently your cheapest option to London, with prices starting at $593. Additional round-trip tickets that might be worth considering are offered by Virgin Atlantic and Delta, with the lowest prices starting at $597 and $616, respectively. You may be able to fly from Ontario to London for 37% less than the average price by searching for these airlines.

What are the most popular routes from Ontario to London?

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

What does ONT to LHR mean?

ONT stands for Ontario Airport, while LHR stands for London Heathrow Airport. These codes are often called IATA codes, a set of identifiers established by IATA (International Air Transport Association) that is widely used by airlines and the aviation industry. London Gatwick Airport (LGW), London Stansted Airport (STN), London City Airport (LCY), London Luton Airport (LTN), London Southend Airport (SEN) are some additional IATA codes for airports related to your trip.

Top 6 airlines flying from Ontario to London

The chart below displays the airlines Cheapflights users traveling from Ontario to London choose most often. Cheapest and average prices are based on aggregated data from the past 12 months.
AirlineCheapestAverageFlexibilityOn-time
DeltaCheapest$547Average$981FlexibilityNo cancel feeOn-timeN/A
Search Delta flights
United AirlinesCheapest$600Average$669FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
Virgin AtlanticCheapest$611Average$840FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights
British AirwaysCheapest$641Average$931FlexibilityNo cancel feeOn-time70%
Search British Airways flights
American AirlinesCheapest$664Average$956FlexibilityNo cancel feeOn-time71%
Search American Airlines flights
IberiaCheapest$754Average$1,043FlexibilityNo cancel feeOn-time77%
Search Iberia flights

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

Deals for Ontario to London flights are sourced from 900+ travel sites when you use Cheapflights. When all flight results come back, Cheapflights lets you sort and filter flights using different criteria to choose better, like price, airport, cabin class, and plenty of other options.

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

Cheapflights simply makes it quick and affordable to book flights from Ontario to London by bringing together all flight options from hundreds of airlines and agencies online — and put it in one place for you to choose from. Plus, Cheapflights is 100% free to use for all.

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

Yes, we can. To see specific flights from Ontario to London with no change fees, users can toggle flexible booking options after using the search form above to find flights.

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

Yes, and it’s super simple to set up. Perform a flight search above and use a valid email address to enable the Price Alert feature. That’s it!

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