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.

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

JetBlue, British Airways, and Virgin Atlantic are the most popular carriers operating from Ontario to London

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 44% of people opting to fly with this airline when traveling to London. Keep in mind that there are 23 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 31m.

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.

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.

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 September 2026, there are 5 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.

$296 Cheap Flights from Ontario to London in 2026

Discover deals from 900+ travel sites with momondo.

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.

12:00 pm - 12:20 pmONT Ontario-LHR London Heathrow

16h 20m1 stop Seattle/Tacoma Intl

2:45 pm - 10:39 pmLHR London Heathrow-ONT Ontario

15h 54m1 stop Seattle/Tacoma Intl

$798Alaska Airlines

Tue, Mar 2 - Sat, Mar 13

6:00 am - 9:20 amONT Ontario-LHR London Heathrow

19h 20m2 stops San Francisco Calgary

2:45 pm - 10:38 amLHR London Heathrow-ONT Ontario

27h 53m1 stop Seattle/Tacoma Intl

$802Multiple Airlines

Tue, Dec 1 - Sat, Jan 9

6:00 am - 7:10 amONT Ontario-LHR London Heathrow

17h 10m2 stops San Francisco Montreal Pierre Elliott Trudeau Intl

2:45 pm - 10:39 pmLHR London Heathrow-ONT Ontario

15h 54m1 stop Seattle/Tacoma Intl

$802Multiple Airlines

Mon, Mar 1 - Mon, Mar 8

7:00 am - 12:20 pmONT Ontario-LHR London Heathrow

21h 20m1 stop Seattle/Tacoma Intl

2:45 pm - 10:41 pmLHR London Heathrow-ONT Ontario

15h 56m1 stop Seattle/Tacoma Intl

$807Alaska Airlines

Mon, Feb 1 - Mon, Feb 8

2:17 pm - 12:15 pmONT Ontario-LHR London Heathrow

13h 58m1 stop Dallas/Fort Worth

2:35 pm - 9:59 pmLHR London Heathrow-ONT Ontario

15h 24m1 stop Phoenix Sky Harbor Intl

$847British Airways

Sun, Jan 24 - Sat, Jan 30

2:22 pm - 12:00 pmONT Ontario-LHR London Heathrow

13h 38m1 stop Dallas/Fort Worth

2:45 pm - 10:02 pmLHR London Heathrow-ONT Ontario

15h 17m1 stop Dallas/Fort Worth

$850British Airways

Tue, Dec 8 - Sun, Dec 27

6:00 am - 11:40 amONT Ontario-LHR London Heathrow

21h 40m2 stops Salt Lake City Atlanta Hartsfield-Jackson

8:55 am - 10:59 pmLHR London Heathrow-ONT Ontario

22h 04m2 stops Paris Charles de Gaulle Seattle/Tacoma Intl

$879Delta

Wed, Dec 2 - Wed, Dec 16

11:56 am - 10:40 amONT Ontario-LHR London Heathrow

15h 44m1 stop Seattle/Tacoma Intl

6:30 am - 5:12 pmLHR London Heathrow-ONT Ontario

18h 42m2 stops Amsterdam Schiphol Seattle/Tacoma Intl

$907Delta

Mon, Oct 26 - Tue, Nov 3

1:33 pm - 11:15 amONT Ontario-LHR London Heathrow

13h 42m1 stop San Francisco

10:25 am - 11:06 pmLHR London Heathrow-ONT Ontario

20h 41m2 stops Chicago O'Hare Intl San Francisco

$910United Airlines

Tue, Mar 2 - Fri, Mar 5

1:33 pm - 11:15 amONT Ontario-LHR London Heathrow

13h 42m1 stop San Francisco

10:25 am - 11:06 pmLHR London Heathrow-ONT Ontario

20h 41m2 stops Chicago O'Hare Intl San Francisco

$911United Airlines

Tue, Mar 2 - Fri, Mar 5

Cheap last minute flights

Enter your travel dates to find the best prices.

10:39 pm - 8:45 pmONT Ontario-LHR London Heathrow

14h 06m1 stop New York John F Kennedy Intl

11:55 am - 8:57 pmLHR London Heathrow-ONT Ontario

17h 02m1 stop New York John F Kennedy Intl

$947JetBlue

Thu, Sep 10 - Fri, Sep 18

10:39 pm - 8:45 pmONT Ontario-LHR London Heathrow

14h 06m1 stop New York John F Kennedy Intl

8:15 am - 8:57 pmLHR London Heathrow-ONT Ontario

20h 42m1 stop New York John F Kennedy Intl

$947JetBlue

Thu, Sep 10 - Thu, Sep 17

6:00 am - 11:20 amONT Ontario-LHR London Heathrow

21h 20m1 stop Seattle/Tacoma Intl

9:55 am - 11:47 pmLHR London Heathrow-ONT Ontario

21h 52m2 stops Amsterdam Schiphol Salt Lake City

$1,059Virgin Atlantic

Wed, Sep 9 - Wed, Sep 16

6:00 am - 6:45 amONT Ontario-LHR London Heathrow

16h 45m2 stops Salt Lake City Boston Logan Intl

11:45 am - 11:47 pmLHR London Heathrow-ONT Ontario

20h 02m2 stops Amsterdam Schiphol Salt Lake City

$1,063Virgin Atlantic

Wed, Sep 9 - Wed, Sep 16

6:02 am - 3:05 pmONT Ontario-LHR London Heathrow

25h 03m1 stop Seattle/Tacoma Intl

5:00 pm - 2:16 pmLHR London Heathrow-ONT Ontario

29h 16m1 stop Seattle/Tacoma Intl

$1,081Alaska Airlines

Mon, Sep 7 - Wed, Sep 9

1:18 pm - 9:40 amONT Ontario-LHR London Heathrow

12h 22m1 stop Denver Intl

2:50 pm - 8:53 pmLHR London Heathrow-ONT Ontario

14h 03m1 stop Denver Intl

$1,082United Airlines

Wed, Sep 9 - Tue, Sep 22

6:02 am - 3:05 pmONT Ontario-LHR London Heathrow

25h 03m1 stop Seattle/Tacoma Intl

5:00 pm - 7:03 pmLHR London Heathrow-ONT Ontario

34h 03m1 stop Seattle/Tacoma Intl

$1,082Alaska Airlines

Wed, Sep 9 - Wed, Sep 16

1:18 pm - 9:40 amONT Ontario-LHR London Heathrow

12h 22m1 stop Denver Intl

2:50 pm - 8:53 pmLHR London Heathrow-ONT Ontario

14h 03m1 stop Denver Intl

$1,085United Airlines

Sun, Sep 6 - Tue, Sep 22

1:04 pm - 10:30 amONT Ontario-LHR London Heathrow

13h 26m1 stop Phoenix Sky Harbor Intl

10:05 am - 3:16 pmLHR London Heathrow-ONT Ontario

13h 11m1 stop Phoenix Sky Harbor Intl

$1,100British Airways

Wed, Sep 9 - Tue, Oct 6

1:17 pm - 10:50 amONT Ontario-LHR London Heathrow

13h 33m1 stop Phoenix Sky Harbor Intl

4:10 pm - 10:43 pmLHR London Heathrow-ONT Ontario

14h 33m1 stop Phoenix Sky Harbor Intl

$1,574British Airways

Sun, Sep 6 - Sun, Sep 13

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Air Canada flights from Ontario to London

Our best Air Canada deals on Ontario to London flight tickets

Air Canada

Mar 2

ONT6:00 amOntario

21h 50m

2 stops

LHR11:50 amLondon Heathrow

Mar 5

LHR6:00 pmLondon Heathrow

34h 20m

2 stops

ONT8:20 pmOntario

$891

Air Canada

Mar 2

ONT6:00 amOntario

21h 50m

2 stops

LHR11:50 amLondon Heathrow

Mar 5

LHR6:00 pmLondon Heathrow

34h 20m

2 stops

ONT8:20 pmOntario

$892

Air Canada

Mar 2

ONT6:00 amOntario

21h 50m

2 stops

LHR11:50 amLondon Heathrow

Mar 5

LHR2:30 pmLondon Heathrow

16h 36m

2 stops

ONT11:06 pmOntario

$906

Delta flights from Ontario to London

Our best Delta deals on Ontario to London flight tickets

Delta

Oct 26

ONT11:56 amOntario

15h 44m

1 stop

LHR10:40 amLondon Heathrow

Nov 3

LHR6:30 amLondon Heathrow

18h 42m

2 stops

ONT5:12 pmOntario

$907

Delta

Oct 26

ONT6:00 amOntario

20h 00m

2 stops

LHR9:00 amLondon Heathrow

Nov 3

LHR6:30 amLondon Heathrow

24h 13m

2 stops

ONT10:43 pmOntario

$912

Delta

Sep 30

ONT1:04 pmOntario

19h 36m

2 stops

LCY4:40 pmLondon City

Oct 7

LCY8:25 amLondon City

22h 18m

2 stops

ONT10:43 pmOntario

$936

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Tue 3/2

12:00 pm-12:20 pm

1 stop16h 20m

London Heathrow

Sat 3/13

2:45 pm-10:39 pm

1 stop15h 54m

$798

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Tue 12/1

6:00 am-9:20 am

2 stops19h 20m

London Heathrow

Sat 1/9

2:45 pm-10:38 am

1 stop27h 53m

$802

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Mon 3/1

6:00 am-7:10 am

2 stops17h 10m

London Heathrow

Mon 3/8

2:45 pm-10:39 pm

1 stop15h 54m

$802

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Mon 2/1

7:00 am-12:20 pm

1 stop21h 20m

London Heathrow

Mon 2/8

2:45 pm-10:41 pm

1 stop15h 56m

$807

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Sun 1/24

2:17 pm-12:15 pm

1 stop13h 58m

London Heathrow

Sat 1/30

2:35 pm-9:59 pm

1 stop15h 24m

$847

Quickest round-trip

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Tue 12/8

2:22 pm-12:00 pm

1 stop13h 38m

London Heathrow

Sun 12/27

2:45 pm-10:02 pm

1 stop15h 17m

$850

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Wed 12/2

6:00 am-11:40 am

2 stops21h 40m

London Heathrow

Wed 12/16

8:55 am-10:59 pm

2 stops22h 04m

$879

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Mon 10/26

11:56 am-10:40 am

1 stop15h 44m

London Heathrow

Tue 11/3

6:30 am-5:12 pm

2 stops18h 42m

$907

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Tue 3/2

1:33 pm-11:15 am

1 stop13h 42m

London Heathrow

Fri 3/5

10:25 am-11:06 pm

2 stops20h 41m

$910

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Tue 3/2

1:33 pm-11:15 am

1 stop13h 42m

London Heathrow

Fri 3/5

10:25 am-11:06 pm

2 stops20h 41m

$911

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 typical price of a round-trip flight between Ontario and London?

Prices are currently low for flights on this route.

Typical prices usually range from $922 to $923.
The lowest price recently found on this route was $798.

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 December is another great option to travel to London, with average flight prices from Ontario averaging around $676.

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 $894. If your travel schedule is flexible, try to avoid departing on a Saturday because tickets tend to average around $1,014. 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 $757 when looking at flights departing at noon. Flights to London are more costly in the afternoon, with an average ticket price of $972. Departure times in the afternoon fall within the peak daily travel times, which is why tickets can be more expensive.

Can stopping save me money on Ontario to London flights?

You could potentially save up to 41% on your flight if you consider stops on a Ontario to London flight.

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

Best Price Found	$296
Fastest flight time	13h 18m
Direct flights	None

The best one-way flight to London from Ontario in the past 72 hours is $296. The best round-trip flight deal from Ontario to London found on momondo in the last 72 hours is $798.

The fastest flight from Ontario to London takes 13h 18m

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

Search flight deals

Frequently asked questions about flying from Ontario to London

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 13h 18m.
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 September 2026, there are 5 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 42% of all bookings. The subsequent popular airlines are Virgin Atlantic at 24%, British Airways at 22%, and Delta at 12%.

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
Virgin Atlantic	PriceFrom $469	Free Cancellation	Rating 7.4 696 reviews	Search Virgin Atlantic flights
Delta	PriceFrom $572	Free Cancellation	Rating 7.8 8,557 reviews	Search Delta flights
British Airways	PriceFrom $615	Free Cancellation	Rating 6.7 8,202 reviews	Search British Airways flights
United Airlines	PriceFrom $665	Free Cancellation	Rating 7.4 10,165 reviews	Search United Airlines flights
Alaska Airlines	PriceFrom $806	Free Cancellation	Rating 7.9 12,876 reviews	Search Alaska Airlines flights

Hounslow

Gatwick

Milton Keynes

Hayes

Wembley

Luton

Croydon

Dover

Richmond

Stansted

Kingston upon Thames

Harrow

Cobham

Watford

Slough

Eastbourne

Worthing

Hook

Uxbridge

Romford

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.

An easier way to manage your London trip

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Fly into one of these airports located in London

London City Airport

London Gatwick Airport

London Heathrow Airport

London Luton Airport

London Southend Airport

London Stansted Airport

Cheap flights from Ontario to London from $296

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Ontario to London departing on 10/2. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

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Air Canada flights from Ontario to London

Our best Air Canada deals on Ontario to London flight tickets

Delta flights from Ontario to London

Our best Delta deals on Ontario to London flight tickets

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

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How to get the cheapest flight ticket from Ontario to London

What is the typical price of a round-trip flight between Ontario and London?

What is the cheapest month to fly to London?

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

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

Can stopping save me money on Ontario to London flights?

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

What airlines fly to London?

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

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

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

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

When to book flights from Ontario to London

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

Best Price Found

Fastest flight time

Direct flights

Frequently asked questions about flying from Ontario to London

Best airlines flying from Ontario to London

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

Traveling to a place near London?

Why use momondo?

An easier way to manage your London trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.

Get notified when prices go down

Daily price changes in your inbox - only with Price Alerts.

Find better results for your trip to the United Kingdom

Fly into one of these airports located in London

Airports listed have a maximum distance of 35.6 mi from London

Fly your favorite airline to London

Airlines are sorted and displayed according to clicks in the past 7 days on momondo

Cabin classes currently available on flights to London

List of cabin classes available on flights landing in London. Availability may vary depending on flight origin and airline.

Popular cities in the United Kingdom

Popular flights according to clicks in the last 7 days on momondo

Fly to other destinations from Ontario

According to popular flight searches on momondo this year

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