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

Alaska Airlines is the most popular carrier 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.

€409 Cheap Flights from London to Ontario in 2026/27

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.

09:00 - 22:48LHR London Heathrow-ONT Ontario

21h 48m2 stops Zurich San Francisco

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

20h 40m1 stop Denver Intl

€439United Airlines

Fri, 13 Nov - Sat, 28 Nov

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

22h 11m2 stops Zurich San Francisco

13:29 - 09:40ONT Ontario-LHR London Heathrow

12h 11m1 stop Denver Intl

€441United Airlines

Fri, 23 Oct - Thu, 5 Nov

07:30 - 20:51LHR London Heathrow-ONT Ontario

21h 21m2 stops Frankfurt am Main Denver Intl

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

21h 15m1 stop San Francisco

€446United Airlines

Tue, 3 Nov - Tue, 10 Nov

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

18h 45m2 stops Frankfurt am Main San Francisco

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

20h 40m1 stop Denver Intl

€447United Airlines

Wed, 4 Nov - Wed, 11 Nov

07:30 - 20:31LHR London Heathrow-ONT Ontario

21h 01m2 stops Frankfurt am Main San Francisco

07:00 - 12:00ONT Ontario-LHR London Heathrow

21h 00m1 stop Chicago O'Hare Intl

€447United Airlines

Tue, 13 Oct - Fri, 13 Nov

09:00 - 20:26LHR London Heathrow-ONT Ontario

19h 26m2 stops Zurich San Francisco

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

12h 40m1 stop Denver Intl

€448United Airlines

Thu, 21 Jan - Mon, 25 Jan

09:00 - 20:26LHR London Heathrow-ONT Ontario

19h 26m2 stops Zurich San Francisco

06:00 - 10:15ONT Ontario-LHR London Heathrow

20h 15m1 stop Houston George Bush Intcntl

€449United Airlines

Thu, 21 Jan - Mon, 25 Jan

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

18h 45m2 stops Frankfurt am Main San Francisco

16:17 - 16:50ONT Ontario-LHR London Heathrow

16h 33m2 stops San Francisco Frankfurt am Main

€451United Airlines

Tue, 3 Nov - Tue, 10 Nov

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

20h 50m3 stops Frankfurt am Main Newark Denver Intl

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

12h 40m1 stop Denver Intl

€455United Airlines

Thu, 21 Jan - Mon, 25 Jan

13:45 - 23:06LHR London Heathrow-ONT Ontario

41h 21m2 stops Zurich San Francisco

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

20h 40m1 stop Denver Intl

€456United Airlines

Fri, 19 Feb - Wed, 10 Mar

Cheap last-minute flights

Enter your travel dates to find the best prices.

13:40 - 21:59LHR London Heathrow-ONT Ontario

16h 19m1 stop Houston George Bush Intcntl

13:24 - 09:40ONT Ontario-LHR London Heathrow

12h 16m1 stop Denver Intl

€473United Airlines

Fri, 25 Sep - Wed, 30 Sep

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

14h 44m1 stop San Francisco

13:52 - 11:10ONT Ontario-LHR London Heathrow

13h 18m1 stop San Francisco

€474United Airlines

Sat, 26 Sep - Fri, 2 Oct

10:00 - 21:59LHR London Heathrow-ONT Ontario

19h 59m1 stop Houston George Bush Intcntl

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

20h 40m1 stop Denver Intl

€474United Airlines

Sun, 27 Sep - Sat, 10 Oct

10:35 - 17:51LHR London Heathrow-ONT Ontario

15h 16m1 stop San Francisco

13:24 - 09:40ONT Ontario-LHR London Heathrow

12h 16m1 stop Denver Intl

€475United Airlines

Thu, 24 Sep - Thu, 1 Oct

14:50 - 20:58LHR London Heathrow-ONT Ontario

14h 08m1 stop Denver Intl

13:24 - 09:40ONT Ontario-LHR London Heathrow

12h 16m1 stop Denver Intl

€477United Airlines

Fri, 25 Sep - Sun, 11 Oct

06:30 - 17:19LHR London Heathrow-ONT Ontario

18h 49m2 stops Amsterdam Schiphol Seattle/Tacoma Intl

11:56 - 15:35ONT Ontario-LHR London Heathrow

19h 39m1 stop Seattle/Tacoma Intl

€480KLM

Thu, 24 Sep - Wed, 7 Oct

06:30 - 17:19LHR London Heathrow-ONT Ontario

18h 49m2 stops Amsterdam Schiphol Seattle/Tacoma Intl

11:56 - 15:35ONT Ontario-LHR London Heathrow

19h 39m1 stop Seattle/Tacoma Intl

€488KLM

Thu, 24 Sep - Wed, 7 Oct

10:55 - 23:47LHR London Heathrow-ONT Ontario

20h 52m1 stop Salt Lake City

06:20 - 11:20ONT Ontario-LHR London Heathrow

21h 00m1 stop Seattle/Tacoma Intl

€495Virgin Atlantic

Thu, 24 Sep - Wed, 7 Oct

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

14h 24m1 stop Seattle/Tacoma Intl

14:13 - 15:05ONT Ontario-LHR London Heathrow

16h 52m1 stop Seattle/Tacoma Intl

€499Alaska Airlines

Fri, 25 Sep - Thu, 8 Oct

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

14h 24m1 stop Seattle/Tacoma Intl

14:13 - 15:05ONT Ontario-LHR London Heathrow

16h 52m1 stop Seattle/Tacoma Intl

€500Alaska Airlines

Fri, 25 Sep - Thu, 8 Oct

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United Airlines flights from London to Ontario

Our best United Airlines deals on London to Ontario flight tickets

United Airlines

13 Nov

LHR09:00London Heathrow

21h 48m

2 stops

ONT22:48Ontario

28 Nov

ONT05:00Ontario

20h 40m

1 stop

LHR09:40London Heathrow

€439

United Airlines

23 Oct

LHR08:40London Heathrow

22h 11m

2 stops

ONT22:51Ontario

5 Nov

ONT13:29Ontario

12h 11m

1 stop

LHR09:40London Heathrow

€441

United Airlines

3 Nov

LHR07:30London Heathrow

21h 21m

2 stops

ONT20:51Ontario

10 Nov

ONT06:00Ontario

21h 15m

1 stop

LHR11:15London Heathrow

€446

Delta flights from London to Ontario

Our best Delta deals on London to Ontario flight tickets

Delta

19 Nov

LHR06:30London Heathrow

18h 46m

2 stops

ONT17:16Ontario

30 Nov

ONT23:10Ontario

23h 15m

1 stop

LHR06:25London Heathrow

€477

Delta

28 Sept

LHR08:40London Heathrow

22h 00m

2 stops

ONT22:40Ontario

13 Oct

ONT06:20Ontario

21h 00m

1 stop

LHR11:20London Heathrow

€478

Delta

24 Oct

LHR11:40London Heathrow

19h 03m

1 stop

ONT22:43Ontario

4 Nov

ONT13:35Ontario

12h 25m

1 stop

LHR10:00London Heathrow

€494

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Fri 13/11

09:00-22:48

2 stops21h 48m

Ontario

Sat 28/11

05:00-09:40

1 stop20h 40m

€439

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Fri 23/10

08:40-22:51

2 stops22h 11m

Ontario

Thu 5/11

13:29-09:40

1 stop12h 11m

€441

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Tue 3/11

07:30-20:51

2 stops21h 21m

Ontario

Tue 10/11

06:00-11:15

1 stop21h 15m

€446

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Wed 4/11

09:30-20:15

2 stops18h 45m

Ontario

Wed 11/11

05:00-09:40

1 stop20h 40m

€447

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Tue 13/10

07:30-20:31

2 stops21h 01m

Ontario

Fri 13/11

07:00-12:00

1 stop21h 00m

€447

Fastest return journey

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Thu 21/1

09:00-20:26

2 stops19h 26m

Ontario

Mon 25/1

13:00-09:40

1 stop12h 40m

€448

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Thu 21/1

09:00-20:26

2 stops19h 26m

Ontario

Mon 25/1

06:00-10:15

1 stop20h 15m

€449

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Tue 3/11

09:30-20:15

2 stops18h 45m

Ontario

Tue 10/11

16:17-16:50

2 stops16h 33m

€451

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Thu 21/1

07:30-20:20

3 stops20h 50m

Ontario

Mon 25/1

13:00-09:40

1 stop12h 40m

€455

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Fri 19/2

13:45-23:06

2 stops41h 21m

Ontario

Wed 10/3

05:00-09:40

1 stop20h 40m

€456

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 €514 to €730.
The lowest price recently found on this route was €439.

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 €520.

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	€409
Fastest flight time	15h 44m
Direct flights	None

The best one-way flight to Ontario from London in the past 72 hours is €409. The best return flight deal from London to Ontario found on momondo in the last 72 hours is €439.

The fastest flight from London to Ontario takes 15h 44m

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 15h 44m 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.