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Cheap flights from Ontario to London from $325

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 10/1. 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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0 bags

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

Cheap round-trip flights

Delta Logo
6:45 am - 12:50 pmONT-LHR
22h 05m1 stop
Delta Logo
8:55 am - 9:14 pmLHR-ONT
20h 19m2 stops
$523Delta
Find Deal
mar., déc. 30 - ven., janv. 9
Delta Logo
11:50 am - 2:15 pmONT-LHR
18h 25m1 stop
Delta Logo
6:20 am - 10:41 pmLHR-ONT
23h 21m2 stops
$524Delta
Find Deal
mer., oct. 1 - jeu., oct. 30
Delta Logo
11:55 am - 12:35 pmONT-LHR
16h 40m2 stops
Delta Logo
6:20 am - 9:20 pmLHR-ONT
22h 00m2 stops
$528Delta
Find Deal
mer., oct. 1 - jeu., oct. 30
KLM Logo
11:36 am - 9:00 amONT-LHR
13h 24m1 stop
KLM Logo
10:45 am - 4:14 pmLHR-ONT
13h 29m1 stop
$532KLM
Find Deal
mer., nov. 5 - jeu., nov. 13
Virgin Atlantic Logo
7:05 am - 9:00 amONT-LHR
18h 55m1 stop
Virgin Atlantic Logo
6:20 am - 10:41 pmLHR-ONT
24h 21m2 stops
$573Virgin Atlantic
Find Deal
ven., oct. 31 - mar., nov. 4
Virgin Atlantic Logo
7:05 am - 7:15 amONT-LHR
16h 10m1 stop
Virgin Atlantic Logo
6:20 am - 10:41 pmLHR-ONT
23h 21m2 stops
$574Virgin Atlantic
Find Deal
ven., oct. 24 - ven., oct. 31
KLM Logo
11:36 am - 7:50 amONT-LHR
13h 14m1 stop
KLM Logo
12:20 pm - 10:41 pmLHR-ONT
18h 21m1 stop
$581KLM
Find Deal
jeu., oct. 30 - mer., nov. 5
United Airlines Logo
1:15 pm - 9:40 amONT-LHR
12h 25m1 stop
United Airlines Logo
2:50 pm - 8:24 pmLHR-ONT
13h 34m1 stop
$608United Airlines
Find Deal
lun., oct. 6 - mer., oct. 22
United Airlines Logo
1:15 pm - 12:20 pmONT-LHR
15h 05m1 stop
United Airlines Logo
2:50 pm - 8:43 pmLHR-ONT
13h 53m1 stop
$609United Airlines
Find Deal
lun., sept. 1 - mar., sept. 16
Iberia Logo
10:53 am - 9:00 amONT-LHR
14h 07m1 stop
Iberia Logo
12:00 pm - 6:54 pmLHR-ONT
14h 54m1 stop
$643Iberia
Find Deal
mer., sept. 10 - ven., sept. 19

Delta flights from Ontario to London Heathrow Airport

Our best Delta deals on Ontario to London Heathrow Airport flight tickets
Delta
Aug 25
ONT11:45 amOntario
15h 25m
1 stop
LHR11:10 amLondon Heathrow
Sep 10
LHR9:20 amLondon Heathrow
17h 51m
1 stop
ONT7:11 pmOntario
$522
Find similar
Delta
Dec 30
ONT6:45 amOntario
22h 05m
1 stop
LHR12:50 pmLondon Heathrow
Jan 9
LHR8:55 amLondon Heathrow
20h 19m
2 stops
ONT9:14 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

KLM flights from Ontario to London Heathrow Airport

Our best KLM deals on Ontario to London Heathrow Airport flight tickets
KLM
Nov 5
ONT11:36 amOntario
13h 24m
1 stop
LHR9:00 amLondon Heathrow
Nov 13
LHR10:45 amLondon Heathrow
13h 29m
1 stop
ONT4:14 pmOntario
$532
Find similar
KLM
Oct 30
ONT11:36 amOntario
13h 14m
1 stop
LHR7:50 amLondon Heathrow
Nov 5
LHR12:20 pmLondon Heathrow
18h 21m
1 stop
ONT10:41 pmOntario
$581
Find similar
KLM
Sep 4
ONT11:40 amOntario
18h 35m
1 stop
LHR2:15 pmLondon Heathrow
Sep 14
LHR9:20 amLondon Heathrow
21h 03m
1 stop
ONT10:23 pmOntario
$624
Find similar

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 août 17, 2025.
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

mar. 12/30

6:45 am-12:50 pm

1 stop22h 05m

London Heathrow

ven. 1/9

8:55 am-9:14 pm

2 stops20h 19m

$523

OntarioLondon

ONT - LHR

ONTLHR

Ontario

mer. 10/1

11:50 am-2:15 pm

1 stop18h 25m

London Heathrow

jeu. 10/30

6:20 am-10:41 pm

2 stops23h 21m

$524

OntarioLondon

ONT - LHR

ONTLHR

Ontario

mer. 10/1

11:55 am-12:35 pm

2 stops16h 40m

London Heathrow

jeu. 10/30

6:20 am-9:20 pm

2 stops22h 00m

$528

OntarioLondon

ONT - LHR

ONTLHR

Ontario

mer. 11/5

11:36 am-9:00 am

1 stop13h 24m

London Heathrow

jeu. 11/13

10:45 am-4:14 pm

1 stop13h 29m

$532

OntarioLondon

ONT - LHR

ONTLHR

Ontario

ven. 10/31

7:05 am-9:00 am

1 stop18h 55m

London Heathrow

mar. 11/4

6:20 am-10:41 pm

2 stops24h 21m

$573

OntarioLondon

ONT - LHR

ONTLHR

Ontario

ven. 10/24

7:05 am-7:15 am

1 stop16h 10m

London Heathrow

ven. 10/31

6:20 am-10:41 pm

2 stops23h 21m

$574

OntarioLondon

ONT - LHR

ONTLHR

Ontario

jeu. 10/30

11:36 am-7:50 am

1 stop13h 14m

London Heathrow

mer. 11/5

12:20 pm-10:41 pm

1 stop18h 21m

$581

OntarioLondon

ONT - LHR

ONTLHR

Ontario

lun. 10/6

1:15 pm-9:40 am

1 stop12h 25m

London Heathrow

mer. 10/22

2:50 pm-8:24 pm

1 stop13h 34m

$608

OntarioLondon

ONT - LHR

ONTLHR

Ontario

lun. 9/1

1:15 pm-12:20 pm

1 stop15h 05m

London Heathrow

mar. 9/16

2:50 pm-8:43 pm

1 stop13h 53m

$609

OntarioLondon

ONT - LHR

ONTLHR

Ontario

mer. 9/10

10:53 am-9:00 am

1 stop14h 07m

London Heathrow

ven. 9/19

12:00 pm-6:54 pm

1 stop14h 54m

$643

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

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

The month of October is, on average, the cheapest month to fly to London Heathrow Airport from Ontario, with most prices found around $677. If you’re not able to fly to London Heathrow Airport in October, then April is your next best option. Flight prices from Ontario to London Heathrow Airport during April 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 $776. The most expensive day to fly to London Heathrow Airport is Saturday, with ticket prices averaging around $905.

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 $783. 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 morning are often more expensive with an average ticket price of $895.

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 $851 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 $674 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

Best Price Found

$325

Fastest flight time

12h 25m

Direct flights

None
The best one-way flight to London Heathrow Airport from Ontario in the past 72 hours is $325. The best round-trip flight deal from Ontario to London Heathrow Airport found on momondo in the last 72 hours is $523.
The fastest flight from Ontario to London Heathrow Airport takes 12h 25m
There are no direct flights from Ontario to London Heathrow Airport. Popular non-direct route for this connection is Ontario Airport - London Heathrow Airport.
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  • 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 25m 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 $572Free CancellationRating
8.0
7,986 reviews
Search Delta flights
KLMPriceFrom $580Free CancellationRating
7.8
1,385 reviews
Search KLM flights
IberiaPriceFrom $582Free CancellationRating
7.0
2,883 reviews
Search Iberia flights
Virgin AtlanticPriceFrom $629Free CancellationRating
7.4
657 reviews
Search Virgin Atlantic flights
United AirlinesPriceFrom $633Free CancellationRating
7.4
8,919 reviews
Search United Airlines flights
British AirwaysPriceFrom $648Free CancellationRating
6.6
7,271 reviews
Search British Airways flights
American AirlinesPriceFrom $648Free CancellationRating
7.2
10,000 reviews
Search American Airlines flights

Traveling to a place near London?

Book flights to London if you plan to visit one of these locations
Hounslow
Gatwick
Dover
Slough
Luton
Guildford
Milton Keynes
Dartford
Crawley
Hayes
Chelmsford
Stansted
Salisbury
Brentwood
Ilford
Swindon
Colchester
Folkestone
Stratford-upon-Avon
Watford

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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