Which layover airport has the shortest travel time from Ontario to London?

Flights connecting via Salt Lake City (SLC) have the shortest average one-way travel time: 12h 50m.

What airlines fly to London?

British Airways, Virgin Atlantic and Iberia are the top three most popular airlines that fly to London from Ontario according to our data. British Airways is the first choice among our users, with 50% of people opting to fly with this airline when traveling to London. Keep in mind that there are 19 different airlines that fly to London on a routine basis, so you have a few additional options to choose from.

What is the cheapest airline that flies from Ontario to London?

British Airways, United Airlines, and Delta are the most popular carriers operating from Ontario to London

Which layover airport has the shortest connection time from Ontario to London?

Salt Lake City (SLC) has the shortest average layover time for this route: 1h 13m.

Which layover airport offers the lowest fares from Ontario to London?

Flights via Copenhagen (CPH) offer the lowest average round-trip price of $474.

Which airport is the most popular layover for flights between Ontario and London?

Denver (DEN) was the most common stop: 33% of momondo users choosing 1-stop flights on this route connected there.

When did momondo last update prices for flights from Ontario Airport to London?

Prices for flights from Ontario Airport to London are updated daily.

How many operators does momondo search for flights from Ontario Airport to London?

As of December 2025, there are 6 operators available to choose from for flights from Ontario Airport to London.

How old do you have to be to fly from Ontario Airport to London?

The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from Ontario Airport to London.

What documentation or ID do you need to fly to London?

The necessary travel and health documents for your London trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.

$290 Cheap Flights from Ontario to London in 2025/26

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Find the cheapest flights from Ontario to London

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One-way

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Cheap round-trip flights

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6:00 am - 6:50 am

ONT

LHR

17h 50m1 stop

6:00 am - 10:48 pm

LHR

ONT

23h 48m2 stops

$575Iberia

Tue, Mar 10 - Tue, Mar 17

10:58 am - 10:00 am

ONT

LHR

15h 02m1 stop

7:30 am - 10:48 pm

LHR

ONT

23h 18m2 stops

$577Iberia

Wed, Jan 21 - Thu, Jan 29

10:58 am - 8:35 am

ONT

LHR

13h 37m1 stop

6:00 am - 6:45 pm

LHR

ONT

20h 45m2 stops

$584British Airways

Tue, Jan 13 - Tue, Jan 20

10:56 am - 6:50 am

ONT

LHR

12h 54m1 stop

10:15 am - 6:42 pm

LHR

ONT

15h 27m1 stop

$591British Airways

Tue, Mar 10 - Tue, Mar 17

4:45 pm - 1:15 pm

ONT

LHR

12h 30m1 stop

10:35 am - 6:39 pm

LHR

ONT

16h 04m1 stop

$596British Airways

Mon, Feb 2 - Thu, Feb 19

7:30 am - 10:30 am

ONT

LHR

19h 00m1 stop

6:20 am - 9:05 pm

LHR

ONT

22h 45m2 stops

$598Delta

Wed, Jan 14 - Wed, Jan 21

10:58 am - 11:40 am

ONT

LHR

16h 42m1 stop

7:30 am - 10:48 pm

LHR

ONT

23h 18m2 stops

$602Iberia

Wed, Jan 21 - Sun, Jan 25

3:30 pm - 8:10 pm

ONT

LHR

20h 40m2 stops

6:20 am - 10:51 pm

LHR

ONT

24h 31m2 stops

$603Delta

Tue, Jan 13 - Tue, Jan 20

7:30 am - 10:30 am

ONT

LHR

19h 00m1 stop

12:30 pm - 9:05 pm

LHR

ONT

16h 35m1 stop

$605KLM

Wed, Jan 21 - Thu, Jan 29

6:22 am - 9:00 am

ONT

LGW

18h 38m2 stops

11:20 am - 12:03 pm

LGW

ONT

56h 43m2 stops

$807American Airlines

Wed, Jan 28 - Sun, Feb 1

Iberia flights from Ontario to London

Our best Iberia deals on Ontario to London flight tickets

Iberia

Mar 10

ONT6:00 amOntario

17h 50m

1 stop

LHR6:50 amLondon Heathrow

Mar 17

LHR6:00 amLondon Heathrow

23h 48m

2 stops

ONT10:48 pmOntario

$575

Find similar

Iberia

Jan 21

ONT10:58 amOntario

15h 02m

1 stop

LHR10:00 amLondon Heathrow

Jan 29

LHR7:30 amLondon Heathrow

23h 18m

2 stops

ONT10:48 pmOntario

$577

Find similar

Iberia

Jan 21

ONT10:58 amOntario

16h 42m

1 stop

LHR11:40 amLondon Heathrow

Jan 25

LHR7:30 amLondon Heathrow

23h 18m

2 stops

ONT10:48 pmOntario

$602

Find similar

British Airways flights from Ontario to London

Our best British Airways deals on Ontario to London flight tickets

British Airways

Jan 13

ONT10:58 amOntario

13h 37m

1 stop

LHR8:35 amLondon Heathrow

Jan 20

LHR6:00 amLondon Heathrow

20h 45m

2 stops

ONT6:45 pmOntario

$584

Find similar

British Airways

Mar 10

ONT10:56 amOntario

12h 54m

1 stop

LHR6:50 amLondon Heathrow

Mar 17

LHR10:15 amLondon Heathrow

15h 27m

1 stop

ONT6:42 pmOntario

$591

Find similar

British Airways

Feb 2

ONT4:45 pmOntario

12h 30m

1 stop

LHR1:15 pmLondon Heathrow

Feb 19

LHR10:35 amLondon Heathrow

16h 04m

1 stop

ONT6:39 pmOntario

$596

Find similar

Fly from

Fly to

Route

Depart

Return

Price

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Tue 3/10

6:00 am-6:50 am

1 stop17h 50m

London Heathrow

Tue 3/17

6:00 am-10:48 pm

2 stops23h 48m

$575

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 1/21

10:58 am-10:00 am

1 stop15h 02m

London Heathrow

Thu 1/29

7:30 am-10:48 pm

2 stops23h 18m

$577

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Tue 1/13

10:58 am-8:35 am

1 stop13h 37m

London Heathrow

Tue 1/20

6:00 am-6:45 pm

2 stops20h 45m

$584

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Tue 3/10

10:56 am-6:50 am

1 stop12h 54m

London Heathrow

Tue 3/17

10:15 am-6:42 pm

1 stop15h 27m

$591

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Mon 2/2

4:45 pm-1:15 pm

1 stop12h 30m

London Heathrow

Thu 2/19

10:35 am-6:39 pm

1 stop16h 04m

$596

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 1/14

7:30 am-10:30 am

1 stop19h 00m

London Heathrow

Wed 1/21

6:20 am-9:05 pm

2 stops22h 45m

$598

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 1/21

10:58 am-11:40 am

1 stop16h 42m

London Heathrow

Sun 1/25

7:30 am-10:48 pm

2 stops23h 18m

$602

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Tue 1/13

3:30 pm-8:10 pm

2 stops20h 40m

London Heathrow

Tue 1/20

6:20 am-10:51 pm

2 stops24h 31m

$603

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 1/21

7:30 am-10:30 am

1 stop19h 00m

London Heathrow

Thu 1/29

12:30 pm-9:05 pm

1 stop16h 35m

$605

OntarioLondon

ONT - LGW

ONTLGW

Ontario

Wed 1/28

6:22 am-9:00 am

2 stops18h 38m

London Gatwick

Sun 2/1

11:20 am-12:03 pm

2 stops56h 43m

$807

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first

How to get the cheapest flight ticket from Ontario to London

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

Prices

Airlines

Layovers

What is the cheapest month to fly to London?

The cheapest month to fly to London from Ontario is in October. Flight prices, which tend to average around $679, are often lower during this time because this is during the off-season. The month of January is another great option to travel to London, with average flight prices from Ontario averaging around $684.

What is the cheapest day to depart on your flight to London?

The cheapest day to depart from Ontario to London is on a Wednesday. Travelers who choose to depart for London on a Wednesday will often find tickets for as low as $753. If your travel schedule is flexible, try to avoid departing on a Saturday because tickets tend to average around $848. These prices are subject to change though, so be sure to set up a Price Alert for flights to London.

What is the cheapest time of day to depart on your flight to London?

Flying to London from Ontario at noon is the least expensive time of day to depart. momondo users have found prices as low as $773 when looking at flights departing at noon. Flights to London are more costly in the evening, with an average ticket price of $821. Departure times in the evening fall within the peak daily travel times, which is why tickets can be more expensive.

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

You are more likely to see cheaper flights to London from Ontario when booking weeks ahead of your departure date. In general, you can expect to find flights to London for around $834 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to London from Ontario for as low as $606 on momondo.

When to book flights from Ontario to London

Are you open to changing your travel dates? Check out the ideal times to fly from Ontario to London according to our flight data. Find out which month and days have the cheapest flights.

Estimated round-trip price

Cheap Ontario to London (ONT to LON) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Ontario to London

Fastest flight time	12h 05m
Direct flights	None

The fastest flight from Ontario to London takes 12h 05m

There are no direct flights from Ontario to London. There are no popular flight routes from Ontario to London.

Search flight deals

How far is Ontario to London by plane?
The straight-line distance from Ontario to London is 5417.5 mi. A reasonable flight in good conditions will take 12h 09m.
When did momondo last update prices for flights from Ontario Airport to London?
Prices for flights from Ontario Airport to London are updated daily.
How many operators does momondo search for flights from Ontario Airport to London?
As of December 2025, there are 6 operators available to choose from for flights from Ontario Airport to London.
How old do you have to be to fly from Ontario Airport to London?
The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from Ontario Airport to London.
What documentation or ID do you need to fly to London?
The necessary travel and health documents for your London trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.
What is the most popular airline from Ontario to London?
momondo data reveals that the most frequently booked airline on the route from Ontario to London is United Airlines, representing 27% of all bookings. The subsequent popular airlines are British Airways at 23%, Delta at 19%, and American Airlines at 17%.

Best airlines flying from Ontario to London

Compare and see reviews for airlines that fly from Ontario to London with momondo

Airline	Rating	Free Cancellation	Price
Delta	PriceFrom $570	Free Cancellation	Rating 7.9 8,011 reviews	Search Delta flights
KLM	PriceFrom $580	Free Cancellation	Rating 7.7 1,430 reviews	Search KLM flights
Iberia	PriceFrom $615	Free Cancellation	Rating 7.0 3,040 reviews	Search Iberia flights
American Airlines	PriceFrom $624	Free Cancellation	Rating 7.2 11,047 reviews	Search American Airlines flights
British Airways	PriceFrom $653	Free Cancellation	Rating 6.7 7,562 reviews	Search British Airways flights
United Airlines	PriceFrom $665	Free Cancellation	Rating 7.4 9,066 reviews	Search United Airlines flights

Gatwick

Hounslow

Milton Keynes

Dover

Luton

Slough

Guildford

Hayes

Dartford

Crawley

Brentwood

Wembley

Romford

Watford

Ilford

Cobham

Folkestone

Uxbridge

Stansted

Chelmsford

Why use momondo?

Why should I use momondo to find a flight deal from Ontario to London?

momondo compares prices from hundreds of airlines and agents so you can find and book the best deal on flights from Ontario to London. Millions of users trust and use momondo every year so you are in good hands.

Can I find flights from Ontario to London with flexible booking policies on momondo?

All flight searches from Ontario to London on momondo can be filtered to show those which offer flexible booking policies.

How can momondo help me find flights from Ontario to London?

momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from Ontario to London.

I’m not ready to book a flight from Ontario to London right now. Can momondo alert me if prices change?

Yes. momondo can track prices for Ontario to London flights and alert you when they change. Perform a search to set up the price alert. All that is required is a valid email address.