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

Flights connecting via Dallas (DFW) have the shortest average one-way travel time: 13h 30m.

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

Dallas (DFW) 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?

Dallas (DFW) has the shortest average layover time for this route: 1h 35m.

What airlines fly to London?

British Airways, Iberia and American 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 49% 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?

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

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 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.

$243 Cheap Flights from Ontario to London (ONT-LON) in 2025

Q: 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 $599 to $753. The lowest price recently found on this route was $439.

1 adult

0 bags

Discover deals from 900+ travel sites with momondo.

Save money when you book flights with momondo

Big names and deals

Search 100s of travel sites to compare prices.

Filter for what you want

Free Wi-Fi? Stopover? Instantly customize your results.

Trusted and free

We’re completely free to use - no hidden charges or fees.

Price Alerts

Not ready to book? to track prices.

Search flight deals

Find the cheapest flights from Ontario to London (ONT-LON)

Round-trip

One-way

Last minute

Cheap round-trip flights

6:00 am - 11:20 amONT-LHR

21h 20m1 stop

1:25 pm - 10:41 pmLHR-ONT

17h 16m1 stop

$439Virgin Atlantic

Find Deal

Sun, Oct 5 - Tue, Oct 21

6:00 am - 2:15 pmONT-LHR

24h 15m1 stop

6:30 am - 10:41 pmLHR-ONT

24h 11m2 stops

$441Virgin Atlantic

Find Deal

Sun, Oct 5 - Tue, Oct 21

11:55 am - 1:30 pmONT-LHR

17h 35m1 stop

1:05 pm - 10:22 pmLHR-ONT

17h 17m1 stop

$521KLM

Find Deal

Sun, Oct 5 - Tue, Oct 21

11:50 am - 2:15 pmONT-LHR

18h 25m1 stop

11:30 am - 10:41 pmLHR-ONT

19h 11m2 stops

$523Delta

Find Deal

Sun, Oct 5 - Tue, Oct 21

11:50 am - 2:15 pmONT-LHR

18h 25m1 stop

6:20 am - 10:41 pmLHR-ONT

23h 21m2 stops

$524Delta

Find Deal

Wed, Oct 1 - Thu, Oct 30

4:45 pm - 12:50 pmONT-LHR

12h 05m1 stop

12:00 pm - 6:54 pmLHR-ONT

14h 54m1 stop

$640American Airlines

Find Deal

Sun, Sep 7 - Tue, Sep 23

12:47 pm - 10:50 amONT-LHR

14h 03m1 stop

11:15 am - 6:16 pmLHR-ONT

15h 01m1 stop

$651British Airways

Find Deal

Wed, Sep 10 - Wed, Sep 17

1:53 pm - 10:25 amONT-LHR

12h 32m1 stop

6:00 pm - 10:31 pmLHR-ONT

35h 31m2 stops

$655United Airlines

Find Deal

Wed, Oct 1 - Thu, Oct 30

11:59 pm - 7:30 amONT-LGW

23h 31m2 stops

12:30 pm - 2:57 pmLGW-ONT

34h 27m2 stops

$789American Airlines

Find Deal

Mon, Dec 29 - Thu, Jan 15

6:00 am - 7:00 pmONT-LGW

29h 00m2 stops

11:45 am - 5:53 pmLGW-ONT

62h 08m2 stops

$1,101British Airways

Find Deal

Fri, Dec 12 - Wed, Jan 7

KLM flights from Ontario to London

Our best KLM deals on Ontario to London flight tickets

KLM

Oct 5

ONT11:55 amOntario

17h 35m

1 stop

LHR1:30 pmLondon Heathrow

Oct 21

LHR1:05 pmLondon Heathrow

17h 17m

1 stop

ONT10:22 pmOntario

$521

Find similar

KLM

Nov 25

ONT11:45 amOntario

13h 15m

1 stop

LHR9:00 amLondon Heathrow

Feb 24

LHR10:45 amLondon Heathrow

13h 34m

1 stop

ONT4:19 pmOntario

$531

Find similar

KLM

Sep 15

ONT1:15 pmOntario

12h 35m

1 stop

LHR9:50 amLondon Heathrow

Sep 26

LHR9:20 amLondon Heathrow

17h 55m

1 stop

ONT7:15 pmOntario

$570

Find similar

Delta flights from Ontario to London

Our best Delta deals on Ontario to London flight tickets

Delta

Oct 5

ONT11:50 amOntario

18h 25m

1 stop

LHR2:15 pmLondon Heathrow

Oct 21

LHR11:30 amLondon Heathrow

19h 11m

2 stops

ONT10:41 pmOntario

$523

Find similar

Delta

Oct 1

ONT11:50 amOntario

18h 25m

1 stop

LHR2:15 pmLondon Heathrow

Oct 30

LHR6:20 amLondon Heathrow

23h 21m

2 stops

ONT10:41 pmOntario

$524

Find similar

Delta

Oct 1

ONT11:55 amOntario

15h 30m

2 stops

LHR11:25 amLondon Heathrow

Oct 30

LHR6:20 amLondon Heathrow

22h 00m

2 stops

ONT9:20 pmOntario

$528

Find similar

Fly from

Fly to

Route

Depart

Return

Price

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Sun 10/5

6:00 am-11:20 am

1 stop21h 20m

London Heathrow

Tue 10/21

1:25 pm-10:41 pm

1 stop17h 16m

$439

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Sun 10/5

6:00 am-2:15 pm

1 stop24h 15m

London Heathrow

Tue 10/21

6:30 am-10:41 pm

2 stops24h 11m

$441

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Sun 10/5

11:55 am-1:30 pm

1 stop17h 35m

London Heathrow

Tue 10/21

1:05 pm-10:22 pm

1 stop17h 17m

$521

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Sun 10/5

11:50 am-2:15 pm

1 stop18h 25m

London Heathrow

Tue 10/21

11:30 am-10:41 pm

2 stops19h 11m

$523

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 10/1

11:50 am-2:15 pm

1 stop18h 25m

London Heathrow

Thu 10/30

6:20 am-10:41 pm

2 stops23h 21m

$524

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Sun 9/7

4:45 pm-12:50 pm

1 stop12h 05m

London Heathrow

Tue 9/23

12:00 pm-6:54 pm

1 stop14h 54m

$640

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 9/10

12:47 pm-10:50 am

1 stop14h 03m

London Heathrow

Wed 9/17

11:15 am-6:16 pm

1 stop15h 01m

$651

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 10/1

1:53 pm-10:25 am

1 stop12h 32m

London Heathrow

Thu 10/30

6:00 pm-10:31 pm

2 stops35h 31m

$655

OntarioLondon

ONT - LGW

ONTLGW

Ontario

Mon 12/29

11:59 pm-7:30 am

2 stops23h 31m

London Gatwick

Thu 1/15

12:30 pm-2:57 pm

2 stops34h 27m

$789

OntarioLondon

ONT - LGW

ONTLGW

Ontario

Fri 12/12

6:00 am-7:00 pm

2 stops29h 00m

London Gatwick

Wed 1/7

11:45 am-5:53 pm

2 stops62h 08m

$1,101

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?

What is the cheapest month to fly to London?

The cheapest month to fly to London from Ontario is in September. Flight prices, which tend to average around $666, 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 $678.

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 $761. If your travel schedule is flexible, try to avoid departing on a Saturday because tickets tend to average around $885. 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 $778 when looking at flights departing at noon. Flights to London are more costly in the morning, with an average ticket price of $898. Departure times in the morning 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 $849 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 $674 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

Direct flights	None

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 05m.
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 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 29% of all bookings. The subsequent popular airlines are British Airways at 21%, American Airlines at 19%, and Delta at 19%.

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 $572	Free Cancellation	Rating 7.9 7,977 reviews	Search Delta flights
KLM	PriceFrom $580	Free Cancellation	Rating 7.8 1,382 reviews	Search KLM flights
Iberia	PriceFrom $582	Free Cancellation	Rating 7.0 2,892 reviews	Search Iberia flights
American Airlines	PriceFrom $653	Free Cancellation	Rating 7.2 10,000 reviews	Search American Airlines flights
United Airlines	PriceFrom $660	Free Cancellation	Rating 7.4 8,944 reviews	Search United Airlines flights
British Airways	PriceFrom $662	Free Cancellation	Rating 6.7 7,316 reviews	Search British Airways flights

Hounslow

Gatwick

Luton

Dover

Slough

Milton Keynes

Guildford

Dartford

Crawley

Stansted

Hayes

Chelmsford

Brentwood

Ilford

Folkestone

Colchester

Watford

Canterbury

Richmond

Wembley

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.