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

Flights via Salt Lake City (SLC) offer the lowest average round-trip price of $624.

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.

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

Dallas (DFW) was the most common stop: 25% of momondo users choosing 1-stop flights on this route connected there.

What airlines fly to London?

British Airways, Virgin Atlantic and United Airlines 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 20 different airlines that fly to London on a routine basis, so you have a few additional options to choose from.

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

Flights connecting via Denver (DEN) have the shortest average one-way travel time: 12h 40m.

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 January 2026, 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.

$244 Cheap Flights from Ontario to London in 2026

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Find the cheapest flights from Ontario to London

Round-trip

One-way

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Cheap round-trip flights

Enter your travel dates to find the best prices.

7:30 am - 11:55 am

ONT

LHR

20h 25m

1 stop

8:25 pm - 4:02 pm

LHR

ONT

27h 37m

2 stops

$631Virgin Atlantic

Mon, Feb 23 - Mon, Mar 2

7:30 am - 10:30 am

ONT

LHR

19h 00m

1 stop

8:40 am - 9:05 pm

LHR

ONT

20h 25m

2 stops

$634Delta

Thu, Feb 26 - Thu, Mar 5

1:50 pm - 12:00 pm

ONT

LHR

14h 10m

1 stop

6:30 am - 5:41 pm

LHR

ONT

18h 11m

2 stops

$644United Airlines

Wed, Mar 4 - Wed, Mar 11

5:00 am - 8:25 am

ONT

LHR

19h 25m

2 stops

9:30 am - 10:36 pm

LHR

ONT

20h 06m

2 stops

$649United Airlines

Wed, Mar 4 - Wed, Mar 11

2:39 pm - 11:40 am

ONT

LHR

13h 01m

1 stop

2:25 pm - 10:07 pm

LHR

ONT

14h 42m

1 stop

$652British Airways

Mon, Mar 2 - Mon, Mar 9

6:00 am - 6:50 am

ONT

LHR

16h 50m

1 stop

4:30 pm - 11:59 pm

LHR

ONT

15h 29m

1 stop

$653British Airways

Fri, Feb 27 - Fri, Mar 6

6:00 am - 9:25 am

ONT

LGW

43h 25m

2 stops

5:05 pm - 8:58 pm

LGW

ONT

35h 53m

2 stops

$673Air France

Mon, Apr 13 - Mon, Apr 27

6:00 am - 9:25 am

ONT

LGW

43h 25m

2 stops

5:00 pm - 8:58 pm

LGW

ONT

59h 58m

2 stops

$798Air France

Mon, Apr 13 - Sun, Apr 26

7:00 am - 8:50 am

ONT

LCY

17h 50m

2 stops

7:50 am - 10:29 pm

LCY

ONT

22h 39m

2 stops

$823Iberia

Thu, Feb 26 - Thu, Mar 5

2:08 pm - 8:00 pm

ONT

LGW

21h 52m

2 stops

8:40 pm - 11:46 pm

LGW

ONT

35h 06m

2 stops

$901Iberia

Wed, Apr 15 - Tue, Apr 28

Virgin Atlantic flights from Ontario to London

Our best Virgin Atlantic deals on Ontario to London flight tickets

Virgin Atlantic

Feb 23

ONT7:30 amOntario

20h 25m

1 stop

LHR11:55 amLondon Heathrow

Mar 2

LHR8:25 pmLondon Heathrow

27h 37m

2 stops

ONT4:02 pmOntario

$631

Virgin Atlantic

Feb 23

ONT6:00 amOntario

20h 30m

2 stops

LHR10:30 amLondon Heathrow

Mar 2

LHR8:25 pmLondon Heathrow

27h 37m

2 stops

ONT4:02 pmOntario

$636

KLM flights from Ontario to London

Our best KLM deals on Ontario to London flight tickets

KLM

Feb 23

ONT1:15 pmOntario

14h 25m

1 stop

LHR11:40 amLondon Heathrow

Mar 2

LHR12:20 pmLondon Heathrow

18h 17m

1 stop

ONT10:37 pmOntario

$659

KLM

Feb 11

ONT12:41 pmOntario

14h 59m

1 stop

LHR11:40 amLondon Heathrow

Feb 19

LHR2:30 pmLondon Heathrow

16h 07m

1 stop

ONT10:37 pmOntario

$690

KLM

Feb 2

ONT7:30 amOntario

19h 00m

1 stop

LHR10:30 amLondon Heathrow

Feb 9

LHR12:30 pmLondon Heathrow

16h 35m

1 stop

ONT9:05 pmOntario

$1,073

Fly from

Fly to

Route

Depart

Return

Price

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Mon 2/23

7:30 am-11:55 am

1 stop20h 25m

London Heathrow

Mon 3/2

8:25 pm-4:02 pm

2 stops27h 37m

$631

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Thu 2/26

7:30 am-10:30 am

1 stop19h 00m

London Heathrow

Thu 3/5

8:40 am-9:05 pm

2 stops20h 25m

$634

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 3/4

1:50 pm-12:00 pm

1 stop14h 10m

London Heathrow

Wed 3/11

6:30 am-5:41 pm

2 stops18h 11m

$644

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 3/4

5:00 am-8:25 am

2 stops19h 25m

London Heathrow

Wed 3/11

9:30 am-10:36 pm

2 stops20h 06m

$649

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Mon 3/2

2:39 pm-11:40 am

1 stop13h 01m

London Heathrow

Mon 3/9

2:25 pm-10:07 pm

1 stop14h 42m

$652

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Fri 2/27

6:00 am-6:50 am

1 stop16h 50m

London Heathrow

Fri 3/6

4:30 pm-11:59 pm

1 stop15h 29m

$653

OntarioLondon

ONT - LGW

ONTLGW

Ontario

Mon 4/13

6:00 am-9:25 am

2 stops43h 25m

London Gatwick

Mon 4/27

5:05 pm-8:58 pm

2 stops35h 53m

$673

OntarioLondon

ONT - LGW

ONTLGW

Ontario

Mon 4/13

6:00 am-9:25 am

2 stops43h 25m

London Gatwick

Sun 4/26

5:00 pm-8:58 pm

2 stops59h 58m

$798

OntarioLondon

ONT - LCY

ONTLCY

Ontario

Thu 2/26

7:00 am-8:50 am

2 stops17h 50m

London City

Thu 3/5

7:50 am-10:29 pm

2 stops22h 39m

$823

OntarioLondon

ONT - LGW

ONTLGW

Ontario

Wed 4/15

2:08 pm-8:00 pm

2 stops21h 52m

London Gatwick

Tue 4/28

8:40 pm-11:46 pm

2 stops35h 06m

$901

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 February. Flight prices, which tend to average around $654, are often lower during this time because this is during the off-season. The month of October is another great option to travel to London, with average flight prices from Ontario averaging around $679.

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 $742. If your travel schedule is flexible, try to avoid departing on a Saturday because tickets tend to average around $833. 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 $756 when looking at flights departing at noon. Flights to London are more costly in the evening, with an average ticket price of $806. 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 $846 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 $607 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 30m
Direct flights	None

The fastest flight from Ontario to London takes 12h 30m

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 30m.
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 January 2026, 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 British Airways, representing 29% of all bookings. The subsequent popular airlines are United Airlines at 26%, Delta at 18%, and Iberia at 14%.

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 8,127 reviews	Search Delta flights
KLM	PriceFrom $580	Free Cancellation	Rating 7.7 1,443 reviews	Search KLM flights
Iberia	PriceFrom $615	Free Cancellation	Rating 7.0 3,100 reviews	Search Iberia flights
British Airways	PriceFrom $624	Free Cancellation	Rating 6.7 7,705 reviews	Search British Airways flights
American Airlines	PriceFrom $624	Free Cancellation	Rating 7.2 11,206 reviews	Search American Airlines flights
United Airlines	PriceFrom $662	Free Cancellation	Rating 7.4 9,215 reviews	Search United Airlines flights

Gatwick

Hounslow

Milton Keynes

Luton

Dover

Slough

Guildford

Crawley

Wembley

Dartford

Hayes

Brentwood

Harrow

Watford

Cobham

Folkestone

Romford

Stansted

Croydon

Richmond

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.