$373+ Cheap flights from Ontario (ONT) to Heathrow (LHR)
This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 7/27. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — LHR
Mar 4 — Mar 111
1 adult, Economy
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Find cheap flights from Ontario to Heathrow with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
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Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheap flight deals from Ontario to Heathrow
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Cheapest flights from Ontario to HeathrowExplore the most affordable flight options available from Ontario to Heathrow. Find the lowest fares from popular airlines and budget airlines, with prices last updated on February 2, 2026.
Explore the most affordable flight options available from Ontario to Heathrow. Find the lowest fares from popular airlines and budget airlines, with prices last updated on February 2, 2026.
This KLM deal was found by Cheapflights users on 2/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/57:30 am
ONT
- LHR
1 stop19h 00m
KLM
Thu 3/126:30 am
LHR
- ONT
2 stops21h 30m
KLM
Deal found 2/2![KLM logo]()
$636
This Delta deal was found by Cheapflights users on 2/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/56:00 am
ONT
- LHR
2 stops17h 05m
Delta
Thu 3/126:30 am
LHR
- ONT
2 stops17h 42m
Delta
Deal found 2/2![Delta logo]()
$640
This United Airlines deal was found by Cheapflights users on 1/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/181:40 pm
ONT
- LHR
1 stop15h 20m
United Airlines
Wed 3/259:30 am
LHR
- ONT
2 stops20h 06m
United Airlines
Deal found 1/31![United Airlines logo]()
$646
This Delta deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/176:00 am
ONT
- LHR
1 stop21h 00m
Delta
Tue 3/3111:45 am
LHR
- ONT
2 stops37h 28m
Delta
Deal found 2/1![Delta logo]()
$650
This Delta deal was found by Cheapflights users on 1/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/811:59 am
ONT
- LHR
1 stop16h 11m
Delta
Wed 4/226:30 am
LHR
- ONT
2 stops24h 07m
Delta
Deal found 1/31![Delta logo]()
$651
This Cheapflightsfares deal was found by Cheapflights users on 1/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/22:39 pm
ONT
- LHR
1 stop13h 01m
British Airways
Mon 3/92:25 pm
LHR
- ONT
1 stop14h 42m
British Airways
Deal found 1/31![British Airways logo]()
$654
This Expedia deal was found by Cheapflights users on 1/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/32:39 pm
ONT
- LHR
1 stop13h 01m
British Airways
Tue 3/102:20 pm
LHR
- ONT
1 stop14h 47m
British Airways
Deal found 1/30![British Airways logo]()
$655
This Delta deal was found by Cheapflights users on 2/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/1511:53 am
ONT
- LHR
2 stops17h 12m
Delta
Tue 5/59:55 am
LHR
- ONT
2 stops20h 42m
Delta
Deal found 2/2![Delta logo]()
$656
This Air Canada deal was found by Cheapflights users on 1/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/65:10 am
ONT
- LHR
2 stops20h 50m
Air Canada
Tue 4/213:05 pm
LHR
- ONT
2 stops34h 42m
Air Canada
Deal found 1/31![Air Canada logo]()
$660
This United Airlines deal was found by Cheapflights users on 1/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/311:27 pm
ONT
- LHR
1 stop16h 43m
United Airlines
Fri 4/107:30 am
LHR
- ONT
2 stops22h 20m
United Airlines
Deal found 1/31![United Airlines logo]()
$663
This United Airlines deal was found by Cheapflights users on 1/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/85:10 am
ONT
- LHR
1 stop20h 30m
United Airlines
Tue 4/215:40 pm
LHR
- ONT
2 stops36h 46m
United Airlines
Deal found 1/31![United Airlines logo]()
$665
Best flights from Ontario to HeathrowDiscover carefully curated flight deals from Ontario to Heathrow that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated February 2, 2026.
Discover carefully curated flight deals from Ontario to Heathrow that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated February 2, 2026.
This Delta deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/176:00 am
ONT
- LHR
1 stop21h 00m
Delta
Tue 3/3111:45 am
LHR
- ONT
2 stops37h 28m
Delta
Deal found 2/1![Delta logo]()
$650
This United Airlines deal was found by Cheapflights users on 1/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/61:40 pm
ONT
- LHR
1 stop14h 20m
United Airlines
Wed 3/111:45 pm
LHR
- ONT
1 stop16h 12m
United Airlines
Deal found 1/31![United Airlines logo]()
$664
This United Airlines deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/181:40 pm
ONT
- LHR
1 stop15h 20m
United Airlines
Wed 3/2511:35 am
LHR
- ONT
1 stop16h 15m
United Airlines
Deal found 2/1![United Airlines logo]()
$664
This Delta deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/2312:57 pm
ONT
- LHR
1 stop13h 03m
Delta
Tue 3/3111:40 am
LHR
- ONT
1 stop18h 54m
Delta
Deal found 2/1![Delta logo]()
$679
This United Airlines deal was found by Cheapflights users on 1/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/121:40 pm
ONT
- LHR
1 stop15h 20m
United Airlines
Tue 3/1711:35 am
LHR
- ONT
1 stop16h 15m
United Airlines
Deal found 1/30![United Airlines logo]()
$664
This Delta deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/2411:59 am
ONT
- LHR
1 stop15h 31m
Delta
Tue 3/3111:40 am
LHR
- ONT
1 stop18h 54m
Delta
Deal found 2/1![Delta logo]()
$679
This United Airlines deal was found by Cheapflights users on 1/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/111:40 pm
ONT
- LHR
1 stop15h 20m
United Airlines
Fri 3/201:45 pm
LHR
- ONT
1 stop16h 12m
United Airlines
Deal found 1/30![United Airlines logo]()
$664
This Delta deal was found by Cheapflights users on 1/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/1812:57 pm
ONT
- LHR
1 stop13h 03m
Delta
Tue 3/3111:40 am
LHR
- ONT
1 stop18h 54m
Delta
Deal found 1/31![Delta logo]()
$679
This Delta deal was found by Cheapflights users on 1/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/811:59 am
ONT
- LHR
1 stop16h 11m
Delta
Fri 4/249:20 am
LHR
- ONT
1 stop17h 13m
Delta
Deal found 1/31![Delta logo]()
$680
This Delta deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/301:20 pm
ONT
- LHR
1 stop12h 40m
Delta
Tue 4/710:55 am
LHR
- ONT
1 stop13h 33m
Delta
Deal found 2/1![Delta logo]()
$680
This Delta deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/311:20 pm
ONT
- LHR
1 stop13h 40m
Delta
Tue 4/710:55 am
LHR
- ONT
1 stop13h 33m
Delta
Deal found 2/1![Delta logo]()
$680
Last-minute flights from Ontario to HeathrowDiscover last-minute flight deals from Ontario to Heathrow. Data last updated February 2, 2026 and is based on user searches.
Discover last-minute flight deals from Ontario to Heathrow. Data last updated February 2, 2026 and is based on user searches.
This United Airlines deal was found by Cheapflights users on 1/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 2/141:53 pm
ONT
- LHR
1 stop14h 07m
United Airlines
Sat 2/2110:05 am
LHR
- ONT
1 stop15h 36m
United Airlines
Deal found 1/31![United Airlines logo]()
$793
This Delta deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 2/151:15 pm
ONT
- LHR
1 stop14h 25m
Delta
Wed 2/2512:30 pm
LHR
- ONT
1 stop16h 35m
Delta
Deal found 2/1![Delta logo]()
$693
This Cheapflightsfares deal was found by Cheapflights users on 1/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/195:02 pm
ONT
- LHR
1 stop12h 13m
British Airways
Thu 2/264:30 pm
LHR
- ONT
1 stop15h 29m
British Airways
Deal found 1/31![British Airways logo]()
$731
This Air Canada deal was found by Cheapflights users on 1/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/196:10 am
ONT
- LHR
2 stops21h 40m
Multiple Airlines
Wed 3/1111:10 am
LHR
- ONT
2 stops18h 08m
Multiple Airlines
Deal found 1/31![Multiple Airlines logo]()
$751
This Iberia deal was found by Cheapflights users on 1/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Iberia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/197:00 am
ONT
- LHR
2 stops18h 15m
Iberia
Wed 3/118:20 am
LHR
- ONT
1 stop21h 10m
Iberia
Deal found 1/31![Iberia logo]()
$757
This United Airlines deal was found by Cheapflights users on 1/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/201:50 pm
ONT
- LHR
1 stop14h 10m
United Airlines
Fri 2/2710:05 am
LHR
- ONT
1 stop15h 36m
United Airlines
Deal found 1/31![United Airlines logo]()
$743
This Cheapflightsfares deal was found by Cheapflights users on 1/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/262:39 pm
ONT
- LHR
1 stop13h 01m
British Airways
Wed 3/112:25 pm
LHR
- ONT
1 stop14h 54m
British Airways
Deal found 1/30![British Airways logo]()
$766
This Cheapflightsfares deal was found by Cheapflights users on 2/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/262:39 pm
ONT
- LHR
1 stop13h 01m
British Airways
Mon 3/92:25 pm
LHR
- ONT
1 stop14h 42m
British Airways
Deal found 2/2![British Airways logo]()
$781
This United Airlines deal was found by Cheapflights users on 1/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/271:50 pm
ONT
- LHR
1 stop14h 10m
United Airlines
Wed 3/410:05 am
LHR
- ONT
1 stop15h 36m
United Airlines
Deal found 1/30![United Airlines logo]()
$664
This Trip.com deal was found by Cheapflights users on 1/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 2/281:15 pm
ONT
- LHR
1 stop14h 25m
Air France
Fri 3/1310:45 am
LHR
- ONT
1 stop17h 15m
Air France
Deal found 1/31![Air France logo]()
$700
This Trip.com deal was found by Cheapflights users on 1/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 2/287:30 am
ONT
- LHR
1 stop19h 00m
KLM
Fri 3/136:30 am
LHR
- ONT
2 stops17h 42m
KLM
Deal found 1/31![KLM logo]()
$739
This Iberia deal was found by Cheapflights users on 1/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Iberia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 2/2810:56 am
ONT
- LHR
1 stop13h 19m
Iberia
Sat 3/72:45 pm
LHR
- ONT
1 stop16h 04m
Iberia
Deal found 1/31![Iberia logo]()
$764
One-way flights from Ontario to HeathrowSearch for one-way flight options from Ontario to Heathrow. Find affordable one-way fares based on user searches. Data last updated February 2, 2026.
Search for one-way flight options from Ontario to Heathrow. Find affordable one-way fares based on user searches. Data last updated February 2, 2026.
This KAYAK deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/2711:25 pm
ONT
- LHR
1 stop13h 20m
JetBlue
Deal found 2/1![JetBlue logo]()
$373
This KAYAK deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/2411:25 pm
ONT
- LHR
1 stop13h 20m
JetBlue
Deal found 2/1![JetBlue logo]()
$374
This KAYAK deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/2511:25 pm
ONT
- LHR
1 stop26h 05m
JetBlue
Deal found 2/1![JetBlue logo]()
$389
This Cheapflightsfares deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 2/175:02 pm
ONT
- LHR
1 stop12h 13m
British Airways
Deal found 2/1![British Airways logo]()
$393
This United Airlines deal was found by Cheapflights users on 1/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 3/141:40 pm
ONT
- LHR
2 stops16h 50m
United Airlines
Deal found 1/31![United Airlines logo]()
$394
This Cheapflightsfares deal was found by Cheapflights users on 1/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/32:39 pm
ONT
- LHR
1 stop13h 36m
British Airways
Deal found 1/31![British Airways logo]()
$395
This Trip.com deal was found by Cheapflights users on 1/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 3/2211:59 am
ONT
- LHR
1 stop15h 31m
Virgin Atlantic
Deal found 1/31![Virgin Atlantic logo]()
$396
This Trip.com deal was found by Cheapflights users on 1/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 2/157:30 am
ONT
- LHR
1 stop19h 00m
Virgin Atlantic
Deal found 1/30![Virgin Atlantic logo]()
$397
This United Airlines deal was found by Cheapflights users on 2/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/26:10 am
ONT
- LHR
1 stop21h 50m
United Airlines
Deal found 2/1![United Airlines logo]()
$399
This Trip.com deal was found by Cheapflights users on 2/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/1812:49 pm
ONT
- LHR
1 stop33h 56m
Virgin Atlantic
Deal found 2/2![Virgin Atlantic logo]()
$400
This Air Canada deal was found by Cheapflights users on 1/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/181:34 pm
ONT
- LHR
2 stops36h 26m
Air Canada
Deal found 1/30![Air Canada logo]()
$401
This British Airways deal was found by Cheapflights users on 1/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 3/225:02 pm
ONT
- LHR
1 stop13h 13m
British Airways
Deal found 1/31![British Airways logo]()
$402
Find flight deals from Ontario to Heathrow
Discover tips and strategies to find the most affordable flight options for your journey from Ontario (ONT) to Heathrow (LHR). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated February 2, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $636 (KLM) |
One-way from | $373 (KAYAK) |
Popular in | June |
Cheapest in | November |
Average price | $703 |
Cheapflights Fare Finder
Customize your flight search to find flights from Ontario to Heathrow 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, Cheapflights users made 2,558,603 searches. Data last updated February 2, 2026.
Use the filters below to find and compare flights from Ontario to London Heathrow Airport that are best for you.
Fly from
Ontario
Fly to
Heathrow
Route
Depart
Return
Price
OntarioLondon
ONT - LHR
ONTLHR
Ontario
Tue 3/17
6:00 am-10:00 am
1 stop21h 00m
London Heathrow
Tue 3/31
11:45 am-5:13 pm
2 stops37h 28m
$650
OntarioLondon
ONT - LHR
ONTLHR
Ontario
Fri 3/6
1:40 pm-12:00 pm
1 stop14h 20m
London Heathrow
Wed 3/11
1:45 pm-10:57 pm
1 stop16h 12m
$664
OntarioLondon
ONT - LHR
ONTLHR
Ontario
Wed 3/18
1:40 pm-12:00 pm
1 stop15h 20m
London Heathrow
Wed 3/25
11:35 am-8:50 pm
1 stop16h 15m
$664
OntarioLondon
ONT - LHR
ONTLHR
Ontario
Thu 3/12
1:40 pm-12:00 pm
1 stop15h 20m
London Heathrow
Tue 3/17
11:35 am-8:50 pm
1 stop16h 15m
$664
OntarioLondon
ONT - LHR
ONTLHR
Ontario
Wed 3/11
1:40 pm-12:00 pm
1 stop15h 20m
London Heathrow
Fri 3/20
1:45 pm-10:57 pm
1 stop16h 12m
$664
OntarioLondon
ONT - LHR
ONTLHR
Ontario
Mon 3/23
12:57 pm-9:00 am
1 stop13h 03m
London Heathrow
Tue 3/31
11:40 am-10:34 pm
1 stop18h 54m
$679
OntarioLondon
ONT - LHR
ONTLHR
Ontario
Tue 3/24
11:59 am-10:30 am
1 stop15h 31m
London Heathrow
Tue 3/31
11:40 am-10:34 pm
1 stop18h 54m
$679
OntarioLondon
ONT - LHR
ONTLHR
Ontario
Wed 3/18
12:57 pm-9:00 am
1 stop13h 03m
London Heathrow
Tue 3/31
11:40 am-10:34 pm
1 stop18h 54m
$679
OntarioLondon
ONT - LHR
ONTLHR
Ontario
Wed 4/8
11:59 am-12:10 pm
1 stop16h 11m
London Heathrow
Fri 4/24
9:20 am-6:33 pm
1 stop17h 13m
$680
OntarioLondon
ONT - LHR
ONTLHR
Ontario
Mon 3/30
1:20 pm-10:00 am
1 stop12h 40m
London Heathrow
Tue 4/7
10:55 am-4:28 pm
1 stop13h 33m
$680
Showing 1-10 of 22 results
Compare providers for flights from Ontario to Heathrow
Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Ontario to Heathrow in February.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy2 stars | Trust Score*2 stars | |
| Price Accuracy3 stars | Trust Score*2 stars | |
| Price Accuracy2 stars | Trust Score*2 stars | |
| Price Accuracy2 stars | Trust Score*3 stars |
- Most accurate provider: When it comes to deals on Ontario-London Heathrow Airport flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Ontario-London Heathrow Airport flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Ontario-London Heathrow Airport flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on Ontario-London Heathrow Airport flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Ontario-London Heathrow Airport flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.
Best time to book a flight from Ontario to Heathrow
Have a flexible travel schedule? Discover the best time to fly to Heathrow from Ontario with our price prediction graph.
ONT-LHR
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.
Cheapflights Insights
Everything you need to know about your flight from Ontario to London Heathrow Airport
How far ahead should I book a flight from Ontario to London Heathrow Airport?
Use this chart to determine the optimal time to book a round-trip flight from Ontario to Heathrow. Price data was last updated on January 30, 2026.
The price you pay for your flight from Ontario to London Heathrow Airport may vary depending on when you book. For the best chance of a lower fare, look to book 62 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.
What is the cheapest month to book a flight from Ontario to London Heathrow Airport?
Currently, December is the cheapest month in which you can book a flight from Ontario to London Heathrow Airport (average of $469). Flying from Ontario to London Heathrow Airport in June is currently the most expensive (average of $700). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.
Reviews of airlines servicing Heathrow
Get insights into the airlines that provide service to Heathrow. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Heathrow. Reviews last updated February 2, 2026.
Read through reviews of airlines operating flights from Ontario to London Heathrow Airport, such as Delta, KLM, and United Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Food
7.2
Overall
7.9
Boarding
8.1
Crew
8.5
Entertainment
7.8
Comfort
7.9
Reviews
1 / 20
10.0
ExcellentAaron,Oct 2024
LAX - LHR
Food
7.2
Overall
7.9
Boarding
8.1
Crew
8.5
Entertainment
7.8
Comfort
7.9
Reviews
1 / 20
10.0
ExcellentAaron,Oct 2024
LAX - LHR
Food
7.2
Overall
7.9
Boarding
8.1
Crew
8.5
Entertainment
7.8
Comfort
7.9
Reviews
1 / 20
10.0
ExcellentAaron,Oct 2024
LAX - LHR
Food
7.2
Overall
7.9
Boarding
8.1
Crew
8.5
Entertainment
7.8
Comfort
7.9
Reviews
1 / 20
10.0
ExcellentAaron,Oct 2024
LAX - LHR
Food
7.2
Overall
7.9
Boarding
8.1
Crew
8.5
Entertainment
7.8
Comfort
7.9
Reviews
1 / 20
10.0
ExcellentAaron,Oct 2024
LAX - LHR
Food
7.2
Overall
7.9
Boarding
8.1
Crew
8.5
Entertainment
7.8
Comfort
7.9
Reviews
1 / 20
10.0
ExcellentAaron,Oct 2024
LAX - LHR
Related info for your journey
Find useful and relevant information for your journey from Ontario to Heathrow. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
Traveling to a place near London Heathrow Airport?
Book flights to London Heathrow Airport if you plan to visit one of these locationsIlford
Hounslow
Croydon
Southend-on-Sea
Harrow
Eastleigh
Gatwick
Dartford
Dover
Winchester
Orpington
Northampton
Watford
Hayes
Borehamwood
Broadway
Aylesbury
Chipping Norton
Horley
Kingston upon Thames
Browse thousands of different options on Cheapflights for your next trip
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Alternative routes for Ontario to Heathrow
See prices for flight routes from nearby airports that may be better suited for you.
Top 5 airlines flying from Ontario to Heathrow
Discover the top 5 airlines that operate flights from Ontario to Heathrow. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated February 2, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$570 | Average$672 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$580 | Average$653 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$624 | Average$756 | FlexibilityNo cancel fee | On-time70% | |
| Cheapest$624 | Average$730 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$662 | Average$872 | FlexibilityNo cancel fee | On-time69% |