$311+ Cheap flights from Ontario (ONT) to Heathrow (LHR)
This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 10/4. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — LHR
Oct 17 — Oct 241
Round-trip
1 adult, Economy
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Find cheap flights from Ontario to Heathrow with Cheapflights
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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
Cheapest
Best
Last-minute
One-way
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 September 17, 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 September 17, 2026.
This Trip.com deal was found by Cheapflights users on 9/16. 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.
Tue 11/312:02 pm -
1 stop16h 18m
Wed 11/112:45 pm -
1 stop35h 32m
Deal found 9/16![Alaska Airlines logo]()
$730
This Trip.com deal was found by Cheapflights users on 9/14. 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.
Wed 10/142:13 pm -
1 stop16h 52m
Wed 10/215:00 pm -
1 stop25h 17m
Deal found 9/14![Alaska Airlines logo]()
$731
This oojo deal was found by Cheapflights users on 9/12. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/1311:13 am -
1 stop19h 52m
Tue 10/205:00 pm -
1 stop28h 16m
Deal found 9/12![Alaska Airlines logo]()
$732
This Delta deal was found by Cheapflights users on 9/13. 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 10/2612:16 pm -
1 stop13h 44m
Wed 11/1112:40 pm -
1 stop16h 14m
Deal found 9/13![Delta logo]()
$736
This Trip.com deal was found by Cheapflights users on 9/13. 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 9/206:00 pm -
1 stop13h 35m
Tue 10/611:40 am -
1 stop19h 03m
Deal found 9/13![Virgin Atlantic logo]()
$737
This Delta deal was found by Cheapflights users on 9/16. 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 11/811:56 am -
1 stop14h 44m
Thu 11/196:30 am -
2 stops18h 49m
Deal found 9/16![Delta logo]()
$738
This Delta deal was found by Cheapflights users on 9/14. 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 10/266:20 am -
1 stop21h 20m
Tue 11/36:20 am -
2 stops24h 23m
Deal found 9/14![Delta logo]()
$739
This Virgin Atlantic deal was found by Cheapflights users on 9/16. 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 Virgin Atlantic is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/146:20 am -
1 stop21h 00m
Wed 10/2110:55 am -
1 stop21h 00m
Deal found 9/16![Virgin Atlantic logo]()
$744
This Alaska Airlines deal was found by Cheapflights users on 9/17. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/132:13 pm -
1 stop16h 52m
Thu 10/225:00 pm -
1 stop14h 42m
Deal found 9/17![Alaska Airlines logo]()
$745
This Alaska Airlines deal was found by Cheapflights users on 9/14. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/1812:02 pm -
1 stop16h 18m
Fri 11/202:45 pm -
1 stop16h 46m
Deal found 9/14![Alaska Airlines logo]()
$746
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 September 17, 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 September 17, 2026.
This Delta deal was found by Cheapflights users on 9/12. 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 3/77:00 am -
2 stops16h 45m
Thu 3/188:40 am -
2 stops20h 34m
Deal found 9/12![Delta logo]()
$752
This KLM deal was found by Cheapflights users on 9/16. 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.
Sun 11/16:20 am -
1 stop20h 20m
Sun 11/810:50 am -
1 stop15h 32m
Deal found 9/16![KLM logo]()
$784
This Alaska Airlines deal was found by Cheapflights users on 9/13. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/1011:13 am -
1 stop19h 52m
Wed 10/145:00 pm -
1 stop25h 17m
Deal found 9/13![Alaska Airlines logo]()
$801
This United Airlines deal was found by Cheapflights users on 9/13. 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 3/21:33 pm -
1 stop13h 42m
Fri 3/510:25 am -
2 stops20h 41m
Deal found 9/13![United Airlines logo]()
$911
This Icelandair deal was found by Cheapflights users on 9/14. 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 Icelandair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 1/2010:05 am -
2 stops16h 45m
Tue 2/212:15 pm -
2 stops17h 30m
Deal found 9/14![Multiple Airlines logo]()
$984
This Delta deal was found by Cheapflights users on 9/14. 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 10/56:00 pm -
1 stop13h 35m
Mon 10/1211:40 am -
1 stop19h 03m
Deal found 9/14![Delta logo]()
$796
This Delta deal was found by Cheapflights users on 9/16. 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.
Sat 11/71:35 pm -
1 stop12h 25m
Thu 11/1910:50 am -
1 stop15h 44m
Deal found 9/16![Delta logo]()
$796
This Icelandair deal was found by Cheapflights users on 9/15. 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 Icelandair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/118:05 am -
2 stops18h 45m
Wed 12/1612:15 pm -
2 stops17h 25m
Deal found 9/15![Multiple Airlines logo]()
$1,078
This Alaska Airlines deal was found by Cheapflights users on 9/14. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/308:59 pm -
1 stop31h 21m
Sat 12/52:45 pm -
1 stop33h 20m
Deal found 9/14![Alaska Airlines logo]()
$1,085
This Icelandair deal was found by Cheapflights users on 9/12. 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 Icelandair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 2/2211:25 am -
2 stops15h 25m
Tue 3/912:15 pm -
2 stops17h 30m
Deal found 9/12![Multiple Airlines logo]()
$1,082
This United Airlines deal was found by Cheapflights users on 9/15. 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 10/89:25 am -
1 stop14h 00m
Sat 10/171:40 pm -
1 stop16h 19m
Deal found 9/15![United Airlines logo]()
$1,207
This Delta deal was found by Cheapflights users on 9/15. 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 11/1811:57 am -
1 stop14h 43m
Sun 11/2910:50 am -
1 stop15h 44m
Deal found 9/15![Delta logo]()
$1,048
Last-minute flights from Ontario to HeathrowDiscover last-minute flight deals from Ontario to Heathrow. Data last updated September 17, 2026 and is based on user searches.
Discover last-minute flight deals from Ontario to Heathrow. Data last updated September 17, 2026 and is based on user searches.
This Trip.com deal was found by Cheapflights users on 9/13. 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 9/206:00 pm -
1 stop13h 35m
Tue 10/611:40 am -
1 stop19h 03m
Deal found 9/13![Virgin Atlantic logo]()
$737
This oojo deal was found by Cheapflights users on 9/12. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/1311:13 am -
1 stop19h 52m
Tue 10/205:00 pm -
1 stop28h 16m
Deal found 9/12![Alaska Airlines logo]()
$732
This Alaska Airlines deal was found by Cheapflights users on 9/17. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/132:13 pm -
1 stop16h 52m
Thu 10/225:00 pm -
1 stop14h 42m
Deal found 9/17![Alaska Airlines logo]()
$745
This Virgin Atlantic deal was found by Cheapflights users on 9/15. 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 Virgin Atlantic is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/131:35 pm -
2 stops18h 00m
Tue 10/2012:45 pm -
2 stops19h 10m
Deal found 9/15![Virgin Atlantic logo]()
$749
This Trip.com deal was found by Cheapflights users on 9/14. 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.
Wed 10/142:13 pm -
1 stop16h 52m
Wed 10/215:00 pm -
1 stop25h 17m
Deal found 9/14![Alaska Airlines logo]()
$731
This Virgin Atlantic deal was found by Cheapflights users on 9/16. 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 Virgin Atlantic is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/146:20 am -
1 stop21h 00m
Wed 10/2110:55 am -
1 stop21h 00m
Deal found 9/16![Virgin Atlantic logo]()
$744
This Delta deal was found by Cheapflights users on 9/13. 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 10/2612:16 pm -
1 stop13h 44m
Wed 11/1112:40 pm -
1 stop16h 14m
Deal found 9/13![Delta logo]()
$736
This Delta deal was found by Cheapflights users on 9/17. 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 10/269:45 am -
1 stop17h 15m
Tue 11/36:20 am -
2 stops18h 03m
Deal found 9/17![Delta logo]()
$738
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 September 17, 2026.
Search for one-way flight options from Ontario to Heathrow. Find affordable one-way fares based on user searches. Data last updated September 17, 2026.
This lol.travel deal was found by Cheapflights users on 9/16. 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 lol.travel is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/410:39 pm -
1 stop14h 06m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/16![JetBlue logo]()
$311
This oojo deal was found by Cheapflights users on 9/14. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/310:39 pm -
1 stop14h 06m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/14![JetBlue logo]()
$316
This Expedia deal was found by Cheapflights users on 9/16. 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.
Mon 3/12:22 pm -
1 stop13h 38m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/16![British Airways logo]()
$320
This Booking.com deal was found by Cheapflights users on 9/16. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 1/64:25 pm -
1 stop13h 10m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/16![British Airways logo]()
$321
This Expedia deal was found by Cheapflights users on 9/14. 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 10/1311:05 pm -
1 stop13h 40m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/14![JetBlue logo]()
$323
This JetBlue deal was found by Cheapflights users on 9/16. 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 JetBlue is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/1710:42 pm -
1 stop14h 03m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/16![JetBlue logo]()
$325
This Jetabroad deal was found by Cheapflights users on 9/13. 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 Jetabroad is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/2610:39 pm -
1 stop26h 51m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/13![JetBlue logo]()
$333
This United Airlines deal was found by Cheapflights users on 9/14. 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 12/281:05 pm -
1 stop34h 20m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/14![United Airlines logo]()
$335
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 September 17, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $730 (Trip.com) |
One-way from | $311 (lol.travel) |
Popular in | June |
Cheapest in | November |
Average price | $1,016 |
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 7,457,451 searches. Data last updated September 17, 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
Cheapest round-trip
OntarioLondon
ONT Ontario - LHR London Heathrow
ONTLHR
Ontario
Mon 10/19
11:05 pm-8:45 pm
1 stop13h 40m
London Heathrow
Wed 12/31
12:00 am-3:00 pm
Nonstop0h 00m
$329
OntarioLondon
ONT Ontario - LHR London Heathrow
ONTLHR
Ontario
Sat 10/17
10:42 pm-8:45 pm
1 stop14h 03m
London Heathrow
Wed 12/31
12:00 am-3:00 pm
Nonstop0h 00m
$329
OntarioLondon
ONT Ontario - LHR London Heathrow
ONTLHR
Ontario
Sun 10/18
11:05 pm-8:45 pm
1 stop13h 40m
London Heathrow
Wed 12/31
12:00 am-3:00 pm
Nonstop0h 00m
$379
OntarioLondon
ONT Ontario - LHR London Heathrow
ONTLHR
Ontario
Tue 10/20
1:22 pm-9:40 am
1 stop12h 18m
London Heathrow
Wed 12/31
12:00 am-3:00 pm
Nonstop0h 00m
$457
OntarioLondon
ONT Ontario - LHR London Heathrow
ONTLHR
Ontario
Mon 10/26
1:35 pm-10:00 am
1 stop13h 25m
London Heathrow
Wed 12/31
12:00 am-3:00 pm
Nonstop0h 00m
$463
OntarioLondon
ONT Ontario - LHR London Heathrow
ONTLHR
Ontario
Wed 10/21
5:00 am-7:15 am
2 stops18h 15m
London Heathrow
Wed 12/31
12:00 am-3:00 pm
Nonstop0h 00m
$463
OntarioLondon
ONT Ontario - LHR London Heathrow
ONTLHR
Ontario
Sat 10/31
11:13 am-12:20 pm
1 stop18h 07m
London Heathrow
Wed 12/31
12:00 am-3:00 pm
Nonstop0h 00m
$513
OntarioLondon
ONT Ontario - LHR London Heathrow
ONTLHR
Ontario
Fri 10/30
6:00 am-10:15 am
1 stop21h 15m
London Heathrow
Wed 12/31
12:00 am-3:00 pm
Nonstop0h 00m
$513
OntarioLondon
ONT Ontario - LHR London Heathrow
ONTLHR
Ontario
Sat 10/17
5:00 am-10:40 am
3 stops21h 40m
London Heathrow
Wed 12/31
12:00 am-3:00 pm
Nonstop0h 00m
$513
Quickest round-trip
OntarioLondon
ONT Ontario - LHR London Heathrow
ONTLHR
Ontario
Thu 10/1
1:24 pm-9:40 am
1 stop12h 16m
London Heathrow
Wed 12/31
12:00 am-3:00 pm
Nonstop0h 00m
$629
Showing 1-10 of 24 resultsSorted by cheapest first
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 September.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy2 stars | Trust Score*1 star | |
| Price Accuracy3 stars | Trust Score*2 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy3 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
What is the cheapest month to book a flight from Ontario to London Heathrow Airport?
Currently, November is the cheapest month in which you can book a flight from Ontario to London Heathrow Airport (average of $665). Flying from Ontario to London Heathrow Airport in June is currently the most expensive (average of $1,592). 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.
How much does it cost to fly round-trip from Ontario to London Heathrow Airport?
Airfare is below average for this route at the moment.
Ontario to London Heathrow Airport flights typically cost between $936 and $1,360 in November.The cheapest round-trip price found within the last 5 days was $730 on Alaska Airlines (Nov 3-Nov 11).
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 September 17, 2026.
Read through reviews of airlines operating flights from Ontario to London Heathrow Airport, such as Alaska Airlines,Delta, andUnited Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Entertainment
7.0
Overall
7.9
Food
7.0
Crew
8.5
Boarding
8.1
Comfort
7.8
Reviews
1 / 20
6.0
GoodAnonymous,Jul 2026
SEA - LHR
Entertainment
7.0
Overall
7.9
Food
7.0
Crew
8.5
Boarding
8.1
Comfort
7.8
Reviews
1 / 20
6.0
GoodAnonymous,Jul 2026
SEA - LHR
Entertainment
7.0
Overall
7.9
Food
7.0
Crew
8.5
Boarding
8.1
Comfort
7.8
Reviews
1 / 20
6.0
GoodAnonymous,Jul 2026
SEA - LHR
Entertainment
7.0
Overall
7.9
Food
7.0
Crew
8.5
Boarding
8.1
Comfort
7.8
Reviews
1 / 20
6.0
GoodAnonymous,Jul 2026
SEA - LHR
Entertainment
7.0
Overall
7.9
Food
7.0
Crew
8.5
Boarding
8.1
Comfort
7.8
Reviews
1 / 20
6.0
GoodAnonymous,Jul 2026
SEA - LHR
Entertainment
7.0
Overall
7.9
Food
7.0
Crew
8.5
Boarding
8.1
Comfort
7.8
Reviews
1 / 20
6.0
GoodAnonymous,Jul 2026
SEA - 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
Dorking
Gatwick
Hounslow
Harrow
Wembley
Southend-on-Sea
Basingstoke
Watford
Northampton
Dartford
Winchester
Croydon
Chipping Norton
Kingston upon Thames
Eastbourne
Slough
Stansted
Sutton
Luton
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Alternative routes for Ontario to Heathrow
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Search flights from Ontario to Heathrow by cabin class
Find flights from Ontario to Heathrow, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Other flights to Heathrow
Explore flights to Heathrow departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on September 17, 2026.
Ontario and Heathrow flights
Browse other Ontario and Heathrow flight options. Last updated on September 17, 2026.
Other flights from Ontario
Browse through other flights departing from Ontario. Flights are based on user searches made on Cheapflights and were last updated on September 17, 2026.
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Check out other popular destinations found by fellow travelers in 2026
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 7,457,451 searches. Data last updated September 17, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$488 | Average$1,016 | FlexibilityNo cancel fee | On-time72% | |
| Cheapest$615 | Average$872 | FlexibilityNo cancel fee | On-time70% | |
| Cheapest$624 | Average$986 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$665 | Average$1,168 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$806 | Average$1,592 | FlexibilityNo cancel fee | On-time75% |