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

Alaska Airlines, United Airlines, and Delta 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.

€409 Cheap Flights from London to Ontario in 2026

Find the cheapest flights from London to Los Angeles

Return

One-way

Last minute

Cheap return flights

Enter your travel dates to find the best prices.

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

19h 16m2 stops Zurich San Francisco

09:01 - 07:25ONT Ontario-LHR London Heathrow

14h 24m1 stop San Francisco

€502United Airlines

Thu, 10 Sep - Thu, 17 Sep

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

19h 15m2 stops Zurich San Francisco

13:29 - 20:35ONT Ontario-LHR London Heathrow

23h 06m2 stops Denver Intl Newark

€503United Airlines

Wed, 18 Nov - Thu, 19 Nov

08:40 - 22:59LHR London Heathrow-ONT Ontario

22h 19m2 stops Zurich San Francisco

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

12h 22m1 stop Denver Intl

€504United Airlines

Fri, 4 Sep - Thu, 17 Sep

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

19h 15m2 stops Zurich San Francisco

06:00 - 07:40ONT Ontario-LHR London Heathrow

17h 40m1 stop Houston George Bush Intcntl

€507United Airlines

Wed, 18 Nov - Thu, 19 Nov

09:00 - 23:06LHR London Heathrow-ONT Ontario

22h 06m2 stops Zurich San Francisco

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

20h 40m1 stop Denver Intl

€507United Airlines

Wed, 2 Dec - Sun, 6 Dec

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

19h 15m2 stops Zurich San Francisco

13:29 - 07:40ONT Ontario-LHR London Heathrow

58h 11m2 stops Denver Intl Houston George Bush Intcntl

€508United Airlines

Wed, 18 Nov - Thu, 19 Nov

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

19h 15m2 stops Zurich San Francisco

13:29 - 07:40ONT Ontario-LHR London Heathrow

58h 11m2 stops Denver Intl Houston George Bush Intcntl

€510United Airlines

Wed, 18 Nov - Thu, 19 Nov

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

21h 01m2 stops Frankfurt am Main San Francisco

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

20h 40m1 stop Denver Intl

€516United Airlines

Thu, 24 Sep - Wed, 30 Sep

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

21h 06m2 stops Munich Franz Josef Strauss San Francisco

07:00 - 06:55ONT Ontario-LHR London Heathrow

15h 55m2 stops Chicago O'Hare Intl Washington, D.C. Dulles Intl

€517United Airlines

Wed, 30 Sep - Wed, 7 Oct

07:25 - 18:11LHR London Heathrow-ONT Ontario

18h 46m2 stops Munich Franz Josef Strauss San Francisco

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

12h 22m1 stop Denver Intl

€518United Airlines

Thu, 3 Sep - Sun, 13 Sep

Cheap last-minute flights

Enter your travel dates to find the best prices.

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

€678United Airlines

Fri, 21 Aug - Wed, 23 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

€685United Airlines

Wed, 19 Aug - Mon, 7 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

€686United Airlines

Wed, 19 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

€688United Airlines

Thu, 20 Aug - Fri, 28 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

€689United Airlines

Fri, 21 Aug - Sun, 30 Aug

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

€691United Airlines

Sat, 22 Aug - Sat, 29 Aug

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

15h 01m1 stop San Francisco

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

12h 11m1 stop Denver Intl

€709United Airlines

Thu, 20 Aug - Sun, 8 Nov

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

€711United Airlines

Fri, 21 Aug - Sun, 30 Aug

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

14h 03m1 stop Denver Intl

13:18 - 12:35ONT Ontario-LHR London Heathrow

15h 17m1 stop Denver Intl

€712United Airlines

Sat, 22 Aug - Sun, 6 Sep

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

€718United Airlines

Thu, 20 Aug - Sat, 12 Sep

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United Airlines flights from London to Ontario

Our best United Airlines deals on London to Ontario flight tickets

United Airlines

10 Sept

LHR08:45London Heathrow

19h 16m

2 stops

ONT20:01Ontario

17 Sept

ONT09:01Ontario

14h 24m

1 stop

LHR07:25London Heathrow

€502

United Airlines

18 Nov

LHR09:00London Heathrow

19h 15m

2 stops

ONT20:15Ontario

19 Nov

ONT13:29Ontario

23h 06m

2 stops

LHR20:35London Heathrow

€503

United Airlines

4 Sept

LHR08:40London Heathrow

22h 19m

2 stops

ONT22:59Ontario

17 Sept

ONT13:18Ontario

12h 22m

1 stop

LHR09:40London Heathrow

€504

Delta flights from London to Ontario

Our best Delta deals on London to Ontario flight tickets

Delta

29 Sept

LHR11:45London Heathrow

18h 55m

2 stops

ONT22:40Ontario

6 Oct

ONT06:00Ontario

20h 20m

2 stops

LHR10:20London Heathrow

€527

Delta

18 Sept

LHR08:55London Heathrow

21h 45m

2 stops

ONT22:40Ontario

4 Oct

ONT06:00Ontario

17h 10m

2 stops

LHR07:10London Heathrow

€532

Delta

18 Sept

LHR08:55London Heathrow

21h 45m

2 stops

ONT22:40Ontario

4 Oct

ONT06:00Ontario

21h 20m

1 stop

LHR11:20London Heathrow

€532

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Thu 10/9

08:45-20:01

2 stops19h 16m

Ontario

Thu 17/9

09:01-07:25

1 stop14h 24m

€502

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Wed 18/11

09:00-20:15

2 stops19h 15m

Ontario

Thu 19/11

13:29-20:35

2 stops23h 06m

€503

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Fri 4/9

08:40-22:59

2 stops22h 19m

Ontario

Thu 17/9

13:18-09:40

1 stop12h 22m

€504

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Wed 18/11

09:00-20:15

2 stops19h 15m

Ontario

Thu 19/11

06:00-07:40

1 stop17h 40m

€507

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Wed 2/12

09:00-23:06

2 stops22h 06m

Ontario

Sun 6/12

05:00-09:40

1 stop20h 40m

€507

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Wed 18/11

09:00-20:15

2 stops19h 15m

Ontario

Thu 19/11

13:29-07:40

2 stops58h 11m

€508

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Wed 18/11

09:00-20:15

2 stops19h 15m

Ontario

Thu 19/11

13:29-07:40

2 stops58h 11m

€510

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Thu 24/9

07:30-20:31

2 stops21h 01m

Ontario

Wed 30/9

05:00-09:40

1 stop20h 40m

€516

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Wed 30/9

07:25-20:31

2 stops21h 06m

Ontario

Wed 7/10

07:00-06:55

2 stops15h 55m

€517

Fastest return journey

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Thu 3/9

07:25-18:11

2 stops18h 46m

Ontario

Sun 13/9

13:18-09:40

1 stop12h 22m

€518

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 €572 to €646.
The lowest price recently found on this route was €502.

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 €515.

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	17h 25m
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 €502.

The fastest flight from London to Ontario takes 17h 25m

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 17h 25m 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.