What is the cheapest airline that flies from London to Ontario?

Alaska Airlines, United Airlines, and British Airways are the most popular carriers operating from London to Ontario

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

Prices for flights from London to Ontario Airport were last updated today.

How old do you have to be to fly from London to Ontario 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 London to Ontario Airport.

What documentation or ID do you need to fly to Ontario Airport?

The travel and health documents required for your trip to Ontario Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s licence, and a passport valid for six-months after you plan to arrive at Ontario Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

€406 Cheap Flights from London to Ontario in 2026

Find the cheapest flights from London to Los Angeles

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One-way

Last minute

Cheap return flights

Enter your travel dates to find the best prices.

08:40 - 23:47LHR London Heathrow-ONT Ontario

23h 07m2 stops Amsterdam Schiphol Salt Lake City

17:15 - 20:10ONT Ontario-LHR London Heathrow

18h 55m2 stops Salt Lake City New York John F Kennedy Intl

€524Delta

Fri, 18 Sep - Fri, 25 Sep

09:00 - 20:15LHR London Heathrow-ONT Ontario

19h 15m2 stops Zurich San Francisco

06:00 - 21:20ONT Ontario-LHR London Heathrow

31h 20m2 stops Houston George Bush Intcntl Newark

€532United Airlines

Wed, 18 Nov - Thu, 19 Nov

11:45 - 22:43LHR London Heathrow-ONT Ontario

18h 58m2 stops Amsterdam Schiphol Seattle/Tacoma Intl

09:45 - 10:30ONT Ontario-LHR London Heathrow

17h 45m2 stops Salt Lake City New York John F Kennedy Intl

€533Delta

Thu, 22 Oct - Tue, 27 Oct

06:30 - 20:25LHR London Heathrow-ONT Ontario

20h 55m2 stops Amsterdam Schiphol Atlanta Hartsfield-Jackson

06:00 - 10:00ONT Ontario-LHR London Heathrow

20h 00m1 stop Salt Lake City

€534Delta

Tue, 27 Oct - Mon, 2 Nov

11:45 - 22:40LHR London Heathrow-ONT Ontario

18h 55m2 stops Amsterdam Schiphol Seattle/Tacoma Intl

18:00 - 15:35ONT Ontario-LHR London Heathrow

13h 35m1 stop Seattle/Tacoma Intl

€534Delta

Fri, 18 Sep - Thu, 24 Sep

08:40 - 22:45LHR London Heathrow-ONT Ontario

22h 05m2 stops Amsterdam Schiphol Seattle/Tacoma Intl

06:00 - 15:35ONT Ontario-LHR London Heathrow

25h 35m1 stop Seattle/Tacoma Intl

€535Delta

Thu, 3 Sep - Thu, 1 Oct

08:45 - 22:51LHR London Heathrow-ONT Ontario

22h 06m2 stops Zurich San Francisco

05:00 - 07:15ONT Ontario-LHR London Heathrow

18h 15m2 stops Denver Intl Newark

€537United Airlines

Thu, 17 Sep - Wed, 30 Sep

06:55 - 22:59LHR London Heathrow-ONT Ontario

24h 04m2 stops Munich Franz Josef Strauss Chicago O'Hare Intl

05:00 - 07:15ONT Ontario-LHR London Heathrow

18h 15m2 stops Denver Intl Newark

€538United Airlines

Sat, 19 Sep - Fri, 25 Sep

08:40 - 21:52LHR London Heathrow-ONT Ontario

21h 12m2 stops Amsterdam Schiphol Atlanta Hartsfield-Jackson

11:54 - 15:35ONT Ontario-LHR London Heathrow

19h 41m1 stop Seattle/Tacoma Intl

€539Delta

Thu, 3 Sep - Tue, 8 Sep

10:55 - 16:35LHR London Heathrow-ONT Ontario

13h 40m1 stop Salt Lake City

18:00 - 15:35ONT Ontario-LHR London Heathrow

13h 35m1 stop Seattle/Tacoma Intl

€540Delta

Wed, 16 Sep - Tue, 22 Sep

Cheap last-minute flights

Enter your travel dates to find the best prices.

16:15 - 22:59LHR London Heathrow-ONT Ontario

14h 44m1 stop San Francisco

13:18 - 09:40ONT Ontario-LHR London Heathrow

12h 22m1 stop Denver Intl

€721United Airlines

Thu, 27 Aug - Sun, 30 Aug

10:35 - 18:11LHR London Heathrow-ONT Ontario

15h 36m1 stop San Francisco

13:18 - 09:40ONT Ontario-LHR London Heathrow

12h 22m1 stop Denver Intl

€722United Airlines

Thu, 27 Aug - Mon, 7 Sep

16:15 - 22:59LHR London Heathrow-ONT Ontario

14h 44m1 stop San Francisco

13:18 - 09:40ONT Ontario-LHR London Heathrow

12h 22m1 stop Denver Intl

€723United Airlines

Fri, 28 Aug - Sat, 5 Sep

17:00 - 23:24LHR London Heathrow-ONT Ontario

14h 24m1 stop Seattle/Tacoma Intl

11:36 - 12:20ONT Ontario-LHR London Heathrow

16h 44m1 stop Seattle/Tacoma Intl

€724Alaska Airlines

Mon, 24 Aug - Sun, 24 Jan

16:15 - 22:59LHR London Heathrow-ONT Ontario

14h 44m1 stop San Francisco

13:18 - 09:40ONT Ontario-LHR London Heathrow

12h 22m1 stop Denver Intl

€725United Airlines

Fri, 28 Aug - Mon, 31 Aug

14:50 - 20:53LHR London Heathrow-ONT Ontario

14h 03m1 stop Denver Intl

13:18 - 09:40ONT Ontario-LHR London Heathrow

12h 22m1 stop Denver Intl

€742United Airlines

Mon, 24 Aug - Mon, 31 Aug

14:50 - 20:53LHR London Heathrow-ONT Ontario

14h 03m1 stop Denver Intl

13:18 - 09:40ONT Ontario-LHR London Heathrow

12h 22m1 stop Denver Intl

€742United Airlines

Mon, 24 Aug - Sun, 6 Sep

13:00 - 20:01LHR London Heathrow-ONT Ontario

15h 01m1 stop San Francisco

13:18 - 09:40ONT Ontario-LHR London Heathrow

12h 22m1 stop Denver Intl

€744United Airlines

Mon, 24 Aug - Mon, 31 Aug

14:10 - 22:35LHR London Heathrow-ONT Ontario

16h 25m1 stop Chicago O'Hare Intl

13:18 - 09:40ONT Ontario-LHR London Heathrow

12h 22m1 stop Denver Intl

€746United Airlines

Thu, 27 Aug - Mon, 31 Aug

11:25 - 20:01LHR London Heathrow-ONT Ontario

16h 36m2 stops Denver Intl San Francisco

13:18 - 09:40ONT Ontario-LHR London Heathrow

12h 22m1 stop Denver Intl

€748United Airlines

Thu, 27 Aug - Mon, 31 Aug

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Alaska Airlines flights from London to Ontario

Our best Alaska Airlines deals on London to Ontario flight tickets

Alaska Airlines

2 Oct

LHR17:00London Heathrow

14h 24m

1 stop

ONT23:24Ontario

9 Oct

ONT14:13Ontario

16h 52m

1 stop

LHR15:05London Heathrow

€546

Alaska Airlines

17 Sept

LHR17:00London Heathrow

14h 24m

1 stop

ONT23:24Ontario

6 Oct

ONT14:13Ontario

16h 52m

1 stop

LHR15:05London Heathrow

€546

Alaska Airlines

17 Sept

LHR17:00London Heathrow

14h 24m

1 stop

ONT23:24Ontario

6 Oct

ONT14:13Ontario

16h 52m

1 stop

LHR15:05London Heathrow

€547

Delta flights from London to Ontario

Our best Delta deals on London to Ontario flight tickets

Delta

18 Sept

LHR08:40London Heathrow

23h 07m

2 stops

ONT23:47Ontario

25 Sept

ONT18:00Ontario

13h 35m

1 stop

LHR15:35London Heathrow

€524

Delta

22 Oct

LHR09:55London Heathrow

19h 59m

2 stops

ONT21:54Ontario

27 Oct

ONT12:16Ontario

16h 24m

1 stop

LHR11:40London Heathrow

€533

Delta

27 Oct

LHR06:30London Heathrow

20h 55m

2 stops

ONT20:25Ontario

2 Nov

ONT17:03Ontario

19h 07m

2 stops

LHR20:10London Heathrow

€534

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Fri 18/9

08:40-23:47

2 stops23h 07m

Ontario

Fri 25/9

17:15-20:10

2 stops18h 55m

€524

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Wed 18/11

09:00-20:15

2 stops19h 15m

Ontario

Thu 19/11

06:00-21:20

2 stops31h 20m

€532

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Thu 22/10

11:45-22:43

2 stops18h 58m

Ontario

Tue 27/10

09:45-10:30

2 stops17h 45m

€533

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Tue 27/10

06:30-20:25

2 stops20h 55m

Ontario

Mon 2/11

06:00-10:00

1 stop20h 00m

€534

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Fri 18/9

11:45-22:40

2 stops18h 55m

Ontario

Thu 24/9

18:00-15:35

1 stop13h 35m

€534

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Thu 3/9

08:40-22:45

2 stops22h 05m

Ontario

Thu 1/10

06:00-15:35

1 stop25h 35m

€535

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Thu 17/9

08:45-22:51

2 stops22h 06m

Ontario

Wed 30/9

05:00-07:15

2 stops18h 15m

€537

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Sat 19/9

06:55-22:59

2 stops24h 04m

Ontario

Fri 25/9

05:00-07:15

2 stops18h 15m

€538

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Thu 3/9

08:40-21:52

2 stops21h 12m

Ontario

Tue 8/9

11:54-15:35

1 stop19h 41m

€539

Fastest return journey

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Wed 16/9

10:55-16:35

1 stop13h 40m

Ontario

Tue 22/9

18:00-15:35

1 stop13h 35m

€540

Flights are sorted by cheapest return flights first.

Showing 1-10 of 20 resultsSorted by cheapest first

How to get the cheapest flight ticket from London to Ontario

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

Prices

Airlines

What is the typical price of a round-trip flight between London and Ontario?

Prices are currently typical for flights on this route.

Typical prices usually range from €523 to €649.
The lowest price recently found on this route was €524.

What is the cheapest month to fly to Ontario?

If you don’t want to visit Ontario in January, then you should wait until February to fly from London, when ticket prices are also cheap, with an average price of €511.

When to book flights from London to Ontario

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

Estimated return price

Cheap London to Ontario (LON to ONT) flight deals and tips

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

Best price found	€406
Fastest flight time	20h 45m
Direct flights	None

The best one-way flight to Ontario from London in the past 72 hours is €406. The best return flight deal from London to Ontario found on momondo in the last 72 hours is €524.

The fastest flight from London to Ontario takes 20h 45m

There are no direct flights from London to Ontario. There are no popular flight routes from London to Ontario.

Search flight deals

Frequently asked questions about flying from London to Ontario

How far is London to Ontario by plane?
A flight from London to Ontario will travel around 8718.6 km. Typically, this will take 20h 45m by plane in normal conditions.
When did momondo last update prices for flights from London to Ontario Airport?
Prices for flights from London to Ontario Airport were last updated today.
How old do you have to be to fly from London to Ontario 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 London to Ontario Airport.
What documentation or ID do you need to fly to Ontario Airport?
The travel and health documents required for your trip to Ontario Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s licence, and a passport valid for six-months after you plan to arrive at Ontario Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

Why use momondo?

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

To find the flight that best suits your needs, momondo gathers a range of flights from a large pool of different airlines and agents; you can then use our insights and filters to find and book the right flight to Ontario from London.

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

Yes. momondo allows you to filter the results for London to Ontario flights to just show those with flexible booking policies.

How can momondo help me find flights from London to Ontario?

Once you have performed a search in the form on the page, momondo provides useful filters and insights. We can show you the cheapest days and times to fly as well as help filter your options to help you make an informed choice when booking flights to Ontario from London.

I’m not ready to book a flight from London to Ontario right now. Can momondo alert me if prices change?

If you are simply researching potential flights to Ontario, momondo offers a useful price alert feature which will track prices for flights to Ontario from London and alert you when they change.