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Cheap flights from Ontario to London from $336

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 2/28. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
1 adult
0 bags

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Find the cheapest flights from Ontario to London

Cheap round-trip flights

Enter your travel dates to find the best prices.
Iberia Logo
7:00 am - 8:35 am
ONT
-
LHR
17h 35m
1 stop
Iberia Logo
6:15 am - 10:30 pm
LHR
-
ONT
23h 15m
2 stops
$580Iberia
Wed, Mar 4 - Wed, Mar 11
Iberia Logo
6:00 am - 8:15 am
ONT
-
LHR
19h 15m
1 stop
Iberia Logo
11:30 am - 11:46 pm
LHR
-
ONT
20h 16m
2 stops
$596Iberia
Tue, Mar 24 - Thu, Apr 16
British Airways Logo
4:45 pm - 1:15 pm
ONT
-
LHR
12h 30m
1 stop
British Airways Logo
4:30 pm - 11:59 pm
LHR
-
ONT
15h 29m
1 stop
$599British Airways
Mon, Feb 2 - Thu, Feb 26
British Airways Logo
5:02 pm - 1:15 pm
ONT
-
LHR
12h 13m
1 stop
British Airways Logo
2:45 pm - 10:29 pm
LHR
-
ONT
15h 44m
1 stop
$601British Airways
Sun, Feb 15 - Fri, Feb 27
Iberia Logo
7:00 am - 8:15 am
ONT
-
LHR
17h 15m
1 stop
Iberia Logo
8:50 pm - 10:29 pm
LHR
-
ONT
33h 39m
2 stops
$602Iberia
Thu, Feb 19 - Thu, Feb 26
British Airways Logo
3:09 pm - 12:15 pm
ONT
-
LHR
13h 06m
1 stop
British Airways Logo
2:45 pm - 10:29 pm
LHR
-
ONT
15h 44m
1 stop
$604British Airways
Wed, Feb 4 - Fri, Feb 13
British Airways Logo
7:00 am - 6:50 am
ONT
-
LHR
15h 50m
1 stop
British Airways Logo
10:15 am - 6:42 pm
LHR
-
ONT
15h 27m
1 stop
$606British Airways
Tue, Mar 3 - Tue, Mar 10
British Airways Logo
11:59 pm - 10:00 am
ONT
-
LHR
26h 01m
1 stop
British Airways Logo
4:30 pm - 10:06 am
LHR
-
ONT
25h 36m
1 stop
$608British Airways
Mon, Feb 2 - Tue, Feb 17
Iberia Logo
10:58 am - 6:50 am
ONT
-
LHR
35h 52m
1 stop
Iberia Logo
8:55 am - 10:49 pm
LHR
-
ONT
21h 54m
1 stop
$613Iberia
Sat, Jan 31 - Tue, Mar 31
British Airways Logo
2:39 pm - 11:40 am
ONT
-
LHR
13h 01m
1 stop
British Airways Logo
4:30 pm - 11:59 pm
LHR
-
ONT
15h 29m
1 stop
$614British Airways
Thu, Feb 19 - Thu, Feb 26

British Airways flights from Ontario to London Heathrow Airport

Our best British Airways deals on Ontario to London Heathrow Airport flight tickets
British Airways
Feb 2
ONT4:45 pmOntario
12h 30m
1 stop
LHR1:15 pmLondon Heathrow
Feb 26
LHR4:30 pmLondon Heathrow
15h 29m
1 stop
ONT11:59 pmOntario
$599
British Airways
Feb 15
ONT5:02 pmOntario
12h 13m
1 stop
LHR1:15 pmLondon Heathrow
Feb 27
LHR2:45 pmLondon Heathrow
15h 44m
1 stop
ONT10:29 pmOntario
$601
British Airways
Feb 11
ONT3:09 pmOntario
13h 06m
1 stop
LHR12:15 pmLondon Heathrow
Feb 18
LHR11:45 amLondon Heathrow
16h 00m
1 stop
ONT7:45 pmOntario
$604

Iberia flights from Ontario to London Heathrow Airport

Our best Iberia deals on Ontario to London Heathrow Airport flight tickets
Iberia
Mar 4
ONT7:00 amOntario
17h 35m
1 stop
LHR8:35 amLondon Heathrow
Mar 11
LHR6:15 amLondon Heathrow
23h 15m
2 stops
ONT10:30 pmOntario
$580
Iberia
Mar 24
ONT6:00 amOntario
19h 15m
1 stop
LHR8:15 amLondon Heathrow
Apr 16
LHR11:30 amLondon Heathrow
20h 16m
2 stops
ONT11:46 pmOntario
$596
Iberia
Feb 19
ONT7:00 amOntario
17h 15m
1 stop
LHR8:15 amLondon Heathrow
Feb 26
LHR8:50 pmLondon Heathrow
33h 39m
2 stops
ONT10:29 pmOntario
$602

momondo Fare Finder

 
Customize your flight search to find flights from Ontario to London Heathrow Airport that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, momondo users made 832,500 searches. Data last updated January 21, 2026.
Use the filters below to find and compare flights from Ontario to London Heathrow Airport that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 3/4

7:00 am-8:35 am

1 stop17h 35m

London Heathrow

Wed 3/11

6:15 am-10:30 pm

2 stops23h 15m

$580

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Tue 3/24

6:00 am-8:15 am

1 stop19h 15m

London Heathrow

Thu 4/16

11:30 am-11:46 pm

2 stops20h 16m

$596

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Mon 2/2

4:45 pm-1:15 pm

1 stop12h 30m

London Heathrow

Thu 2/26

4:30 pm-11:59 pm

1 stop15h 29m

$599

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Sun 2/15

5:02 pm-1:15 pm

1 stop12h 13m

London Heathrow

Fri 2/27

2:45 pm-10:29 pm

1 stop15h 44m

$601

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Thu 2/19

7:00 am-8:15 am

1 stop17h 15m

London Heathrow

Thu 2/26

8:50 pm-10:29 pm

2 stops33h 39m

$602

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 2/4

3:09 pm-12:15 pm

1 stop13h 06m

London Heathrow

Fri 2/13

2:45 pm-10:29 pm

1 stop15h 44m

$604

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Tue 3/3

7:00 am-6:50 am

1 stop15h 50m

London Heathrow

Tue 3/10

10:15 am-6:42 pm

1 stop15h 27m

$606

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Mon 2/2

11:59 pm-10:00 am

1 stop26h 01m

London Heathrow

Tue 2/17

4:30 pm-10:06 am

1 stop25h 36m

$608

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Sat 1/31

10:58 am-6:50 am

1 stop35h 52m

London Heathrow

Tue 3/31

8:55 am-10:49 pm

1 stop21h 54m

$613

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Thu 2/19

2:39 pm-11:40 am

1 stop13h 01m

London Heathrow

Thu 2/26

4:30 pm-11:59 pm

1 stop15h 29m

$614

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first
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See travel insights to London from

How to get the cheapest flight ticket from Ontario to London Heathrow Airport

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

What is the cheapest month to fly to London Heathrow Airport?

The month of November is, on average, the cheapest month to fly to London Heathrow Airport from Ontario, with most prices found around $624. If you’re not able to fly to London Heathrow Airport in November, then December is your next best option. Flight prices from Ontario to London Heathrow Airport during December average around $687.

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

Our data shows that Wednesday is the least expensive day to fly to London Heathrow Airport. Tickets to fly out on this day can be as low as $752. The most expensive day to fly to London Heathrow Airport is Saturday, with ticket prices averaging around $854.

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

According to our data, the cheapest time of day to fly to London Heathrow Airport is at noon. momondo users have found flights departing from Ontario to London Heathrow Airport at noon for as low as $759. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. Flights in the evening are often more expensive with an average ticket price of $807.

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

You are more likely to see cheaper flights to London Heathrow Airport from Ontario when booking weeks ahead of your departure date. In general, you can expect to find flights to London Heathrow Airport for around $847 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to London Heathrow Airport from Ontario for as low as $607 on momondo.

When to book flights from Ontario to London Heathrow Airport

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

Cheap Ontario to London Heathrow Airport (ONT to LHR) flight deals and tips

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

Fastest flight time

12h 30m

Direct flights

None
The fastest flight from Ontario to London Heathrow Airport takes 12h 30m
There are no direct flights from Ontario to London Heathrow Airport. There are no popular flight routes from Ontario to London Heathrow Airport.
Search flight deals

  • How far is Ontario to London Heathrow by plane?

    The straight-line distance from Ontario to London Heathrow is 5408.1 mi. Typically, this will take 12h 30m by plane in normal conditions.

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

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

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

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

    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 Heathrow Airport.

  • What documentation or ID do you need to fly to London Heathrow Airport?

    The necessary travel and health documents for your London Heathrow Airport 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 Heathrow Airport?

Best airlines flying from Ontario to London Heathrow Airport

Compare and see reviews for airlines that fly from Ontario to London Heathrow Airport with momondo
Airline
Rating
Free Cancellation
Price
DeltaPriceFrom $570Free CancellationRating
7.9
8,089 reviews
Search Delta flights
KLMPriceFrom $580Free CancellationRating
7.7
1,442 reviews
Search KLM flights
IberiaPriceFrom $615Free CancellationRating
7.0
3,094 reviews
Search Iberia flights
British AirwaysPriceFrom $624Free CancellationRating
6.7
7,689 reviews
Search British Airways flights
American AirlinesPriceFrom $624Free CancellationRating
7.2
11,174 reviews
Search American Airlines flights
United AirlinesPriceFrom $662Free CancellationRating
7.4
9,191 reviews
Search United Airlines flights

Traveling to a place near London?

Book flights to London if you plan to visit one of these locations
Gatwick
Hounslow
Luton
Milton Keynes
Dover
Slough
Guildford
Wembley
Crawley
Dartford
Hayes
Stratford-upon-Avon
Brentwood
Watford
Cobham
Folkestone
Romford
Stansted
Harrow
Croydon

Why use momondo?

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

Finding the right flight to London from Ontario is quick and easy when you have a range of options in front of you, from reputable agents and recognisable airlines. Options that can then be filtered down to find the best fit. That is what momondo does. We make finding flights to London quick and easy, saving you time and money.

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

Yes. momondo allows you to filter the results for Ontario to London flights to just show those with 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 offers price alerts on flights to London from Ontario. After performing a search on this page you should be able to see the price alert set up feature. Simply provide a valid email address and momondo will instantly alert you when prices change.

An easier way to manage your London Heathrow Airport trip

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