ONT - LHR

£231 Find Cheap Flights from Ontario to London Heathrow Airport – Compare and Save

1 adult
1 adult, Economy, 0 bags

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Everything you should know

Cheapest return flight
£543
Typical prices: £482-£783
Alaska Airlines
Sat 3/11Sun 11/11
ONT - LHR • 1 stop
Cheapest one-way flight
£231
Typical prices: £381-£512
JetBlue
Thu 4/10
ONT - LHR • 1 stop
Direct flights
Not available
There are currently no direct flights between Ontario and London Heathrow Airport. You'll need to take a connecting flight to reach the destination.
Insights
Insights
When to travel
June
Cheapest • 33% price drop
July
Most popular
Good to know
+1
Good to know
+1
Top stopover airports
Atlanta Hartsfield-Jackson (ATL)
Cheapest • Avg £431 (return)
Salt Lake City (SLC)
Shortest trip • 13h 06m (one-way)
Insights
Insights
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We hope you enjoy your trip to London Heathrow Airport!
Flight Deals
Booking Insights
Flight Deals

Cheap Flights from Ontario to Heathrow (ONT-LHR)

 
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent return flight deals from Ontario to Heathrow

Tue, 3 Nov - Wed, 11 Nov
Alaska Airlines Logo
12:02 - 12:20ONT  Ontario-LHR London Heathrow
16h 18m1 stop Seattle/Tacoma Intl
Alaska Airlines Logo
14:45 - 18:17LHR  London Heathrow-ONT Ontario
35h 32m1 stop Seattle/Tacoma Intl
£543Alaska Airlines
Wed, 14 Oct - Wed, 21 Oct
Alaska Airlines Logo
14:13 - 15:05ONT  Ontario-LHR London Heathrow
16h 52m1 stop Seattle/Tacoma Intl
Alaska Airlines Logo
17:00 - 10:17LHR  London Heathrow-ONT Ontario
25h 17m1 stop Seattle/Tacoma Intl
£544Alaska Airlines
Tue, 13 Oct - Tue, 20 Oct
Alaska Airlines Logo
11:13 - 15:05ONT  Ontario-LHR London Heathrow
19h 52m1 stop Seattle/Tacoma Intl
Alaska Airlines Logo
17:00 - 13:16LHR  London Heathrow-ONT Ontario
28h 16m1 stop Seattle/Tacoma Intl
£544Alaska Airlines
Mon, 26 Oct - Wed, 11 Nov
Delta Logo
12:16 - 09:00ONT  Ontario-LHR London Heathrow
13h 44m1 stop Atlanta Hartsfield-Jackson
Delta Logo
12:40 - 20:54LHR  London Heathrow-ONT Ontario
16h 14m1 stop Atlanta Hartsfield-Jackson
£547Delta
Sun, 8 Nov - Thu, 19 Nov
Delta Logo
11:56 - 10:40ONT  Ontario-LHR London Heathrow
14h 44m1 stop Seattle/Tacoma Intl
Delta Logo
06:30 - 17:19LHR  London Heathrow-ONT Ontario
18h 49m2 stops Amsterdam Schiphol Seattle/Tacoma Intl
£549Delta
Mon, 26 Oct - Tue, 3 Nov
Delta Logo
06:20 - 10:40ONT  Ontario-LHR London Heathrow
21h 20m1 stop Seattle/Tacoma Intl
Delta Logo
06:20 - 22:43LHR  London Heathrow-ONT Ontario
24h 23m2 stops Paris Charles de Gaulle Seattle/Tacoma Intl
£550Delta
Mon, 26 Oct - Tue, 3 Nov
Delta Logo
17:03 - 20:10ONT  Ontario-LHR London Heathrow
20h 07m2 stops Salt Lake City New York John F Kennedy Intl
Delta Logo
06:20 - 22:43LHR  London Heathrow-ONT Ontario
24h 23m2 stops Paris Charles de Gaulle Seattle/Tacoma Intl
£553Delta
Wed, 14 Oct - Wed, 21 Oct
Virgin Atlantic Logo
06:20 - 11:20ONT  Ontario-LHR London Heathrow
21h 00m1 stop Seattle/Tacoma Intl
Virgin Atlantic Logo
10:55 - 23:55LHR  London Heathrow-ONT Ontario
21h 00m1 stop Salt Lake City
£553Virgin Atlantic
Tue, 13 Oct - Thu, 22 Oct
Alaska Airlines Logo
14:13 - 15:05ONT  Ontario-LHR London Heathrow
16h 52m1 stop Seattle/Tacoma Intl
Alaska Airlines Logo
17:00 - 23:42LHR  London Heathrow-ONT Ontario
14h 42m1 stop Seattle/Tacoma Intl
£554Alaska Airlines
Wed, 18 Nov - Wed, 25 Nov
Alaska Airlines Logo
12:02 - 12:20ONT  Ontario-LHR London Heathrow
16h 18m1 stop Seattle/Tacoma Intl
Alaska Airlines Logo
14:45 - 23:31LHR  London Heathrow-ONT Ontario
16h 46m1 stop Seattle/Tacoma Intl
£555Alaska Airlines
Booking Insights

Price, demand, and travel trends for Ontario to London Heathrow Airport flights

Use KAYAK data on prices, travel dates, airlines, and seasonal trends to compare options and book flights from Ontario to London Heathrow Airport with more confidence.

How much is a return flight from Ontario to London Heathrow Airport?

Return flights from Ontario to London Heathrow Airport start at £543. Prices are typical for this route right now, with typical return fares ranging from £482 to £783. The lowest price found in the past 5 days was £543 on Alaska Airlines.

What's the cheapest day of the week to fly from Ontario to London Heathrow Airport?

Thursday is the cheapest day of the week to fly from Ontario to London Heathrow Airport and is 18% cheaper than the average day. Sunday is the most expensive day with flight prices 17% higher than average. Based on deals found by KAYAK users in the last 12 months.

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

•June is the cheapest month to fly from Ontario to London Heathrow Airport at £394 return.
•July (£987) and January (£942) are the most expensive months.
•The price difference between flying in the cheapest and most expensive months is 150% on average.
This is based on KAYAK aggregated and averaged internal data over the past 12 months.

Find deals

Key details for Ontario to London Heathrow Airport flights

Low season

February

Cheapest flight

£231
Best time to beat the crowds but there is an average 14% increase in price.
Most popular time to fly (69% more expensive on average)
Flights from Ontario to London Heathrow Airport

When to book flights from Ontario to Heathrow

Are your dates flexible? Find out the best times to travel from Ontario to Heathrow based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated return price

Your Ontario to London Heathrow Airport flight questions, answered

Find helpful route details based on KAYAK data, including flight times, airports, airlines, and booking questions.

  • Which airports can I use when flying from Ontario to London Heathrow Airport?

    Flights from Ontario to London Heathrow Airport usually depart from Ontario (ONT) and arrive at London Heathrow (LHR).

  • Which cabin classes can I book on flights from Ontario to London Heathrow Airport?

    Only Economy class is available on flights from Ontario to London Heathrow Airport.

  • Which airports do connecting flights from Ontario to London Heathrow Airport pass through?

    One-stop flights from Ontario to London Heathrow Airport most commonly connect through:

    • Dallas/Fort Worth (DFW) – 30% of one-stop connections
    • Denver Intl (DEN) – 21% of one-stop connections
    • Seattle/Tacoma Intl (SEA) – 20% of one-stop connections
    • Phoenix Sky Harbor Intl (PHX) – 15% of one-stop connections

    Dallas/Fort Worth (DFW) handles the largest share of one-stop connections on this route.

  • Can I save money by using flexible dates for flights from Ontario to London Heathrow Airport?

    Yes. Being flexible with your travel dates can save you up to 30% on the Ontario to London Heathrow Airport route. Thursday is the cheapest departure day at £480 return on average, while Sunday is the most expensive at £686, a difference of £205. KAYAK's flexible dates feature shows options up to 3 days before and after your selected dates, making it easier to compare nearby fares.

  • What popular places can I visit in London Heathrow Airport?

    Some of the most popular sights in London Heathrow Airport are Hyde Park, Tower Bridge, and Royal Albert Hall. These are among the most viewed places in London Heathrow Airport on KAYAK.

  • How long is a flight from Ontario to London Heathrow Airport?

    A direct flight from Ontario to London Heathrow Airport takes 0h 00m, covering 5,407 miles.

  • Do I need a passport to fly from Ontario to London Heathrow Airport?

    Yes, a valid passport is required for this international route. Many destinations require at least six months of validity beyond your travel dates. Check your passport expiry well before booking.

  • How are flight prices from Ontario to London Heathrow Airport looking right now?

    One-way fares from Ontario to London Heathrow Airport are currently lower than usual. Average one-way flight prices are about £239, which is 50% below the typical average for this route.

  • How much time can I save by choosing a different stopover airport from Ontario to London Heathrow Airport?

    Flying via Salt Lake City (SLC) gives the shortest average 1-stop total travel time of 13h 06m, compared to 13h 14m via Denver Intl (DEN) and 13h 31m via Phoenix Sky Harbor Intl (PHX).

  • What is the time difference between Ontario and London Heathrow Airport?

    London Heathrow Airport is 8 hours ahead of Ontario (British Time vs Pacific Time). Plan for the time shift when scheduling connections or first-day activities.

  • Which car hire options are available at London Heathrow Airport (LHR)?

    London Heathrow Airport (LHR) hosts 5 major car hire companies, with daily rates starting from around £5 for economy cars. Top options include:
    • GREEN MOTION
    • DRIVALIA
    • Europcar
    • Alamo
    • Hertz

  • How much should I expect to pay for a Ontario to London Heathrow Airport flight?

    Return flights from Ontario to London Heathrow Airport range from £482 to £783, with an average of £585 over the past 12 months. Anything below £482 counts as a good deal.

Your guide to booking Ontario to London Heathrow Airport flights

Get tips on when to book, when to fly, and what to know before your trip.
  • If your dates are flexible, aim for a Thursday departure instead of Sunday. On this route, Thursday flights average £480 – about £205 less than Sunday (30% savings) based on the last 12 months.
  • If you can choose when to travel, plan your Ontario to London Heathrow Airport trip for June. Fares historically average £394 return in that month – typically £593 less than the most expensive month, which is July (based on the last 12 months).
  • If you're arriving late at night and need somewhere to stay, check out these hotels close to London Heathrow Airport.
    - Hilton London Heathrow Airport

More options for your flight from Ontario to Heathrow

Complete your trip to London with a hotel stay or car hire

Car hire in London
Hotels in London
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