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

JetBlue, United Airlines, and British Airways 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.

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.

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.

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 22 different airlines that fly to London on a routine basis, so you have a few additional options to choose from.

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 August 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.

$285 Cheap Flights from Ontario to London in 2026

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Find the cheapest flights from Ontario to London

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1:35 pm - 7:25 amONT Ontario-LHR London Heathrow

33h 50m1 stop San Francisco

6:50 am - 6:47 pmLHR London Heathrow-ONT Ontario

19h 57m2 stops Brussels Bruxelles-National Chicago O'Hare Intl

$736United Airlines

Sun, Nov 1 - Wed, Nov 4

6:37 pm - 7:25 amONT Ontario-LHR London Heathrow

28h 48m1 stop San Francisco

6:50 am - 6:47 pmLHR London Heathrow-ONT Ontario

19h 57m2 stops Brussels Bruxelles-National Chicago O'Hare Intl

$736United Airlines

Mon, Nov 9 - Thu, Nov 12

6:00 am - 12:20 pmONT Ontario-LHR London Heathrow

22h 20m1 stop Seattle/Tacoma Intl

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

15h 54m1 stop Seattle/Tacoma Intl

$803Alaska Airlines

Sun, Jan 17 - Mon, Jan 25

6:00 am - 12:20 pmONT Ontario-LHR London Heathrow

22h 20m1 stop Seattle/Tacoma Intl

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

15h 54m1 stop Seattle/Tacoma Intl

$803Alaska Airlines

Wed, Dec 2 - Wed, Dec 9

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

13h 38m1 stop Dallas/Fort Worth

2:45 pm - 10:54 pmLHR London Heathrow-ONT Ontario

16h 09m1 stop Seattle/Tacoma Intl

$803Multiple Airlines

Tue, Nov 10 - Tue, Nov 17

5:00 am - 9:20 amONT Ontario-LHR London Heathrow

20h 20m2 stops Denver Intl Calgary

2:45 pm - 11:04 pmLHR London Heathrow-ONT Ontario

16h 19m1 stop Seattle/Tacoma Intl

$803Multiple Airlines

Sun, Nov 1 - Wed, Nov 25

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

13h 38m1 stop Dallas/Fort Worth

2:45 pm - 10:19 pmLHR London Heathrow-ONT Ontario

15h 34m1 stop Dallas/Fort Worth

$834British Airways

Tue, Dec 1 - Sat, Dec 12

2:56 pm - 12:15 pmONT Ontario-LHR London Heathrow

13h 19m1 stop Dallas/Fort Worth

2:45 pm - 10:19 pmLHR London Heathrow-ONT Ontario

15h 34m1 stop Dallas/Fort Worth

$834British Airways

Mon, Dec 7 - Mon, Dec 14

6:20 am - 10:40 amONT Ontario-LHR London Heathrow

20h 20m1 stop Seattle/Tacoma Intl

6:30 am - 7:41 pmLHR London Heathrow-ONT Ontario

21h 11m2 stops Amsterdam Schiphol Atlanta Hartsfield-Jackson

$866Delta

Mon, Nov 2 - Thu, Nov 26

7:07 am - 11:40 amONT Ontario-LHR London Heathrow

20h 33m1 stop Atlanta Hartsfield-Jackson

6:30 am - 5:13 pmLHR London Heathrow-ONT Ontario

18h 43m2 stops Amsterdam Schiphol Seattle/Tacoma Intl

$866Delta

Sun, Nov 1 - Tue, Nov 24

Cheap last minute flights

Enter your travel dates to find the best prices.

11:08 pm - 8:45 pmONT Ontario-LHR London Heathrow

13h 37m1 stop New York John F Kennedy Intl

8:15 am - 9:59 pmLHR London Heathrow-ONT Ontario

21h 44m1 stop New York John F Kennedy Intl

$946JetBlue

Sat, Aug 8 - Sat, Aug 29

10:29 am - 9:00 amONT Ontario-LHR London Heathrow

14h 31m1 stop Dallas/Fort Worth

11:30 am - 10:59 pmLHR London Heathrow-ONT Ontario

19h 29m2 stops Madrid Barajas Dallas/Fort Worth

$1,057Iberia

Mon, Aug 10 - Fri, Aug 28

12:04 pm - 3:05 pmONT Ontario-LHR London Heathrow

19h 01m1 stop Seattle/Tacoma Intl

5:00 pm - 11:24 pmLHR London Heathrow-ONT Ontario

14h 24m1 stop Seattle/Tacoma Intl

$1,089Alaska Airlines

Mon, Aug 10 - Fri, Aug 28

4:07 pm - 3:05 pmONT Ontario-LHR London Heathrow

14h 58m1 stop Phoenix Sky Harbor Intl

11:00 am - 6:15 pmLHR London Heathrow-ONT Ontario

15h 15m1 stop Phoenix Sky Harbor Intl

$1,090British Airways

Mon, Aug 10 - Fri, Aug 28

5:54 pm - 3:05 pmONT Ontario-LHR London Heathrow

13h 11m1 stop Seattle/Tacoma Intl

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

14h 54m1 stop Seattle/Tacoma Intl

$1,090Alaska Airlines

Wed, Aug 12 - Wed, Mar 17

6:01 pm - 3:35 pmONT Ontario-LHR London Heathrow

13h 34m1 stop Seattle/Tacoma Intl

8:40 am - 9:52 pmLHR London Heathrow-ONT Ontario

21h 12m2 stops Amsterdam Schiphol Atlanta Hartsfield-Jackson

$1,144Delta

Mon, Aug 10 - Mon, Aug 17

9:43 am - 1:05 pmONT Ontario-LHR London Heathrow

19h 22m2 stops Salt Lake City Minneapolis St Paul

8:40 am - 10:45 pmLHR London Heathrow-ONT Ontario

22h 05m2 stops Amsterdam Schiphol Seattle/Tacoma Intl

$1,148Delta

Mon, Aug 10 - Mon, Aug 17

12:59 pm - 10:50 amONT Ontario-LHR London Heathrow

13h 51m1 stop Phoenix Sky Harbor Intl

4:25 pm - 9:34 amLHR London Heathrow-ONT Ontario

25h 09m1 stop Dallas/Fort Worth

$1,168British Airways

Sun, Aug 9 - Sun, Aug 16

1:50 pm - 11:10 amONT Ontario-LHR London Heathrow

13h 20m1 stop San Francisco

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

14h 03m1 stop Denver Intl

$1,392United Airlines

Mon, Aug 10 - Mon, Aug 17

6:10 am - 7:15 amONT Ontario-LHR London Heathrow

41h 05m2 stops Chicago O'Hare Intl Newark

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

14h 03m1 stop Denver Intl

$1,629United Airlines

Sat, Aug 8 - Wed, Aug 12

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Delta flights from Ontario to London

Our best Delta deals on Ontario to London flight tickets

Delta

Nov 2

ONT6:20 amOntario

20h 20m

1 stop

LHR10:40 amLondon Heathrow

Nov 26

LHR6:30 amLondon Heathrow

21h 11m

2 stops

ONT7:41 pmOntario

$866

Delta

Nov 1

ONT7:07 amOntario

16h 38m

2 stops

LHR7:45 amLondon Heathrow

Nov 26

LHR6:30 amLondon Heathrow

18h 43m

2 stops

ONT5:13 pmOntario

$870

Delta

Nov 4

ONT7:07 amOntario

16h 38m

2 stops

LHR7:45 amLondon Heathrow

Nov 18

LHR6:30 amLondon Heathrow

18h 43m

2 stops

ONT5:13 pmOntario

$871

Air Canada flights from Ontario to London

Our best Air Canada deals on Ontario to London flight tickets

Air Canada

Oct 31

ONT1:29 pmOntario

36h 51m

2 stops

LHR9:20 amLondon Heathrow

Nov 24

LHR1:25 pmLondon Heathrow

39h 26m

2 stops

ONT8:51 pmOntario

$872

Air Canada

Nov 2

ONT5:00 amOntario

18h 10m

2 stops

LHR7:10 amLondon Heathrow

Nov 25

LHR1:25 pmLondon Heathrow

31h 08m

2 stops

ONT12:33 pmOntario

$875

Air Canada

Oct 31

ONT1:29 pmOntario

36h 51m

2 stops

LHR9:20 amLondon Heathrow

Nov 26

LHR6:00 pmLondon Heathrow

34h 51m

2 stops

ONT8:51 pmOntario

$880

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Sun 11/1

1:35 pm-7:25 am

1 stop33h 50m

London Heathrow

Wed 11/4

6:50 am-6:47 pm

2 stops19h 57m

$736

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Mon 11/9

6:37 pm-7:25 am

1 stop28h 48m

London Heathrow

Thu 11/12

6:50 am-6:47 pm

2 stops19h 57m

$736

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Sun 1/17

6:00 am-12:20 pm

1 stop22h 20m

London Heathrow

Mon 1/25

2:45 pm-10:39 pm

1 stop15h 54m

$803

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Wed 12/2

6:00 am-12:20 pm

1 stop22h 20m

London Heathrow

Wed 12/9

2:45 pm-10:39 pm

1 stop15h 54m

$803

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Tue 11/10

2:22 pm-12:00 pm

1 stop13h 38m

London Heathrow

Tue 11/17

2:45 pm-10:54 pm

1 stop16h 09m

$803

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Sun 11/1

5:00 am-9:20 am

2 stops20h 20m

London Heathrow

Wed 11/25

2:45 pm-11:04 pm

1 stop16h 19m

$803

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Tue 12/1

2:22 pm-12:00 pm

1 stop13h 38m

London Heathrow

Sat 12/12

2:45 pm-10:19 pm

1 stop15h 34m

$834

Quickest round-trip

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Mon 12/7

2:56 pm-12:15 pm

1 stop13h 19m

London Heathrow

Mon 12/14

2:45 pm-10:19 pm

1 stop15h 34m

$834

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Mon 11/2

6:20 am-10:40 am

1 stop20h 20m

London Heathrow

Thu 11/26

6:30 am-7:41 pm

2 stops21h 11m

$866

OntarioLondon

ONT Ontario - LHR London Heathrow

ONTLHR

Ontario

Sun 11/1

7:07 am-11:40 am

1 stop20h 33m

London Heathrow

Tue 11/24

6:30 am-5:13 pm

2 stops18h 43m

$866

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 $823 to $1,085.
The lowest price recently found on this route was $736.

What is the cheapest month to fly to London?

The cheapest month to fly to London from Ontario is in March. Flight prices, which tend to average around $652, are often lower during this time because this is during the off-season. The month of February 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 $844. If your travel schedule is flexible, try to avoid departing on a Saturday because tickets tend to average around $982. 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 $707 when looking at flights departing at noon. Flights to London are more costly in the afternoon, with an average ticket price of $942. 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 31% 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

Fastest flight time	12h 51m
Direct flights	None

The fastest flight from Ontario to London takes 12h 51m

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

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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 12h 51m.
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 August 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 United Airlines, representing 42% of all bookings. The subsequent popular airlines are British Airways at 23%, Virgin Atlantic at 23%, 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
British Airways	PriceFrom $329	Free Cancellation	Rating 6.7 8,153 reviews	Search British Airways flights
Virgin Atlantic	PriceFrom $469	Free Cancellation	Rating 7.5 694 reviews	Search Virgin Atlantic flights
Delta	PriceFrom $535	Free Cancellation	Rating 7.8 8,502 reviews	Search Delta flights
American Airlines	PriceFrom $620	Free Cancellation	Rating 7.1 11,881 reviews	Search American Airlines flights
United Airlines	PriceFrom $665	Free Cancellation	Rating 7.4 10,085 reviews	Search United Airlines flights
Alaska Airlines	PriceFrom $806	Free Cancellation	Rating 7.9 12,781 reviews	Search Alaska Airlines flights

Hounslow

Gatwick

Milton Keynes

Luton

Hayes

Wembley

Dover

Croydon

Stansted

Kingston upon Thames

Slough

Harrow

Watford

Cobham

Richmond

Uxbridge

Worthing

Romford

Ilford

Dunstable

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

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London Southend Airport

London Stansted Airport

Cheap flights from Ontario to London from $285

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 11/11. 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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Delta flights from Ontario to London

Our best Delta deals on Ontario to London flight tickets

Air Canada flights from Ontario to London

Our best Air Canada deals on Ontario to London flight tickets

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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

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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