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

United Airlines, JetBlue, 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.

€408 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 - 22:51LHR London Heathrow-ONT Ontario

22h 11m2 stops Zurich San Francisco

05:00 - 09:40ONT Ontario-LHR London Heathrow

21h 40m1 stop Denver Intl

€440United Airlines

Fri, 16 Oct - Sat, 31 Oct

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

19h 15m2 stops Zurich San Francisco

07:00 - 05:55ONT Ontario-LHR London Heathrow

14h 55m1 stop Chicago O'Hare Intl

€441United Airlines

Wed, 4 Nov - Fri, 4 Dec

08:45 - 20:01LHR London Heathrow-ONT Ontario

19h 16m2 stops Zurich San Francisco

05:00 - 09:40ONT Ontario-LHR London Heathrow

20h 40m1 stop Denver Intl

€442United Airlines

Tue, 15 Sep - Mon, 30 Nov

07:30 - 20:15LHR London Heathrow-ONT Ontario

20h 45m2 stops Frankfurt am Main San Francisco

06:00 - 07:25ONT Ontario-LHR London Heathrow

17h 25m1 stop San Francisco

€446United Airlines

Fri, 20 Nov - Sun, 29 Nov

07:25 - 20:31LHR London Heathrow-ONT Ontario

21h 06m2 stops Munich Franz Josef Strauss San Francisco

09:25 - 11:15ONT Ontario-LHR London Heathrow

17h 50m1 stop San Francisco

€446United Airlines

Wed, 7 Oct - Thu, 5 Nov

07:25 - 20:01LHR London Heathrow-ONT Ontario

20h 36m2 stops Munich Franz Josef Strauss San Francisco

13:35 - 07:25ONT Ontario-LHR London Heathrow

33h 50m1 stop San Francisco

€447United Airlines

Tue, 15 Sep - Mon, 30 Nov

09:30 - 20:15LHR London Heathrow-ONT Ontario

17h 45m2 stops Frankfurt am Main San Francisco

13:00 - 09:40ONT Ontario-LHR London Heathrow

12h 40m1 stop Denver Intl

€448United Airlines

Mon, 26 Oct - Fri, 8 Jan

07:30 - 20:20LHR London Heathrow-ONT Ontario

20h 50m2 stops Frankfurt am Main Denver Intl

06:00 - 11:15ONT Ontario-LHR London Heathrow

21h 15m1 stop San Francisco

€454United Airlines

Thu, 21 Jan - Mon, 25 Jan

07:30 - 20:20LHR London Heathrow-ONT Ontario

20h 50m3 stops Frankfurt am Main Newark Denver Intl

16:03 - 07:25ONT Ontario-LHR London Heathrow

31h 22m1 stop San Francisco

€455United Airlines

Thu, 21 Jan - Mon, 25 Jan

08:40 - 22:51LHR London Heathrow-ONT Ontario

22h 11m2 stops Zurich San Francisco

06:00 - 09:40ONT Ontario-LHR London Heathrow

20h 40m2 stops San Francisco Denver Intl

€460United Airlines

Fri, 16 Oct - Sat, 31 Oct

Cheap last-minute flights

Enter your travel dates to find the best prices.

10:00 - 18:12LHR London Heathrow-ONT Ontario

16h 12m1 stop Houston George Bush Intcntl

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

12h 22m1 stop Denver Intl

€474United Airlines

Sat, 5 Sep - Tue, 8 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

€475United Airlines

Fri, 4 Sep - Tue, 15 Sep

14:50 - 20:55LHR London Heathrow-ONT Ontario

14h 05m1 stop Denver Intl

13:18 - 12:25ONT Ontario-LHR London Heathrow

15h 07m1 stop Denver Intl

€476United Airlines

Fri, 4 Sep - Thu, 17 Sep

14:50 - 20:55LHR London Heathrow-ONT Ontario

14h 05m1 stop Denver Intl

13:18 - 12:25ONT Ontario-LHR London Heathrow

15h 07m1 stop Denver Intl

€477United Airlines

Fri, 4 Sep - Thu, 17 Sep

10:35 - 20:01LHR London Heathrow-ONT Ontario

17h 26m1 stop San Francisco

06:00 - 11:35ONT Ontario-LHR London Heathrow

21h 35m1 stop Houston George Bush Intcntl

€505Lufthansa

Sat, 5 Sep - Fri, 18 Sep

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

14h 24m1 stop Seattle/Tacoma Intl

15:14 - 15:05ONT Ontario-LHR London Heathrow

15h 51m1 stop Seattle/Tacoma Intl

€522Alaska Airlines

Thu, 3 Sep - Thu, 17 Sep

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

14h 24m1 stop Seattle/Tacoma Intl

15:14 - 15:05ONT Ontario-LHR London Heathrow

15h 51m1 stop Seattle/Tacoma Intl

€543Alaska Airlines

Thu, 3 Sep - Thu, 17 Sep

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

14h 24m1 stop Seattle/Tacoma Intl

15:14 - 15:05ONT Ontario-LHR London Heathrow

15h 51m1 stop Seattle/Tacoma Intl

€552Alaska Airlines

Thu, 3 Sep - Thu, 17 Sep

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

14h 24m1 stop Seattle/Tacoma Intl

11:13 - 15:05ONT Ontario-LHR London Heathrow

19h 52m1 stop Seattle/Tacoma Intl

€652Alaska Airlines

Thu, 3 Sep - Wed, 14 Oct

17:00 - 19:03LHR London Heathrow-ONT Ontario

34h 03m1 stop Seattle/Tacoma Intl

19:59 - 15:05ONT Ontario-LHR London Heathrow

35h 06m1 stop Seattle/Tacoma Intl

€662Alaska Airlines

Fri, 4 Sep - Fri, 11 Sep

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Alaska Airlines flights from London to Ontario

Our best Alaska Airlines deals on London to Ontario flight tickets

Alaska Airlines

13 Sept

LHR17:00London Heathrow

14h 24m

1 stop

ONT23:24Ontario

26 Sept

ONT15:14Ontario

15h 51m

1 stop

LHR15:05London Heathrow

€501

Alaska Airlines

6 Sept

LHR17:00London Heathrow

14h 24m

1 stop

ONT23:24Ontario

19 Sept

ONT15:14Ontario

15h 51m

1 stop

LHR15:05London Heathrow

€508

Alaska Airlines

16 Oct

LHR17:00London Heathrow

14h 42m

1 stop

ONT23:42Ontario

29 Oct

ONT14:13Ontario

15h 07m

1 stop

LHR12:20London Heathrow

€508

Delta flights from London to Ontario

Our best Delta deals on London to Ontario flight tickets

Delta

13 Oct

LHR06:30London Heathrow

18h 42m

2 stops

ONT17:12Ontario

20 Oct

ONT13:35Ontario

13h 25m

1 stop

LHR11:00London Heathrow

€477

Delta

12 Oct

LHR06:30London Heathrow

18h 42m

2 stops

ONT17:12Ontario

9 Nov

ONT13:15Ontario

12h 45m

1 stop

LHR10:00London Heathrow

€479

Delta

15 Sept

LHR06:15London Heathrow

22h 09m

2 stops

ONT20:24Ontario

30 Nov

ONT23:10Ontario

23h 15m

1 stop

LHR06:25London Heathrow

€486

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Fri 16/10

08:40-22:51

2 stops22h 11m

Ontario

Sat 31/10

05:00-09:40

1 stop21h 40m

€440

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Wed 4/11

09:00-20:15

2 stops19h 15m

Ontario

Fri 4/12

07:00-05:55

1 stop14h 55m

€441

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Tue 15/9

08:45-20:01

2 stops19h 16m

Ontario

Mon 30/11

05:00-09:40

1 stop20h 40m

€442

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Fri 20/11

07:30-20:15

2 stops20h 45m

Ontario

Sun 29/11

06:00-07:25

1 stop17h 25m

€446

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Wed 7/10

07:25-20:31

2 stops21h 06m

Ontario

Thu 5/11

09:25-11:15

1 stop17h 50m

€446

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Tue 15/9

07:25-20:01

2 stops20h 36m

Ontario

Mon 30/11

13:35-07:25

1 stop33h 50m

€447

Fastest return journey

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Mon 26/10

09:30-20:15

2 stops17h 45m

Ontario

Fri 8/1

13:00-09:40

1 stop12h 40m

€448

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Thu 21/1

07:30-20:20

2 stops20h 50m

Ontario

Mon 25/1

06:00-11:15

1 stop21h 15m

€454

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Thu 21/1

07:30-20:20

3 stops20h 50m

Ontario

Mon 25/1

16:03-07:25

1 stop31h 22m

€455

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Fri 16/10

08:40-22:51

2 stops22h 11m

Ontario

Sat 31/10

06:00-09:40

2 stops20h 40m

€460

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 low for flights on this route.

Typical prices usually range from €533 to €647.
The lowest price recently found on this route was €440.

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 €514.

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	€408
Fastest flight time	14h 03m
Direct flights	None

The best one-way flight to Ontario from London in the past 72 hours is €408. The best return flight deal from London to Ontario found on momondo in the last 72 hours is €440.

The fastest flight from London to Ontario takes 14h 03m

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 14h 03m 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.