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Ontario

$370+ Cheap flights from the United Kingdom to Ontario (ONT)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 5/13. Fares are subject to change and may not be available on all flights or dates of travel.
LHR — ONT
May 6 — May 131
Tue 5/6
Tue 5/13
1 adult, Economy
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Cheap flight deals from United Kingdom to Ontario

Keep the following information in mind while searching for United Kingdom to Ontario flight deals. Data was last updated May 1, 2025.

Most accurate provider

AranGrant
3 stars

Most trusted provider

AranGrant
3 stars

Round-trip from

$521
(Finnair)

One-way from

$370
(Kiwi.com)

Popular in

August

Cheapest in

February

Average price

$638
Provider with most accurate pricing for London (LON)-Los Angeles flight deals.
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From United Kingdom to Ontario
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One-way flight from United Kingdom to Ontario
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Highest demand for flights based on searches. 10% potential increase in price ($74 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($16 potential savings vs. average RT price).
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Average for round-trip flights in May 2025
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Find flight deals from United Kingdom to Ontario

Cheapest flights from United Kingdom to Ontario
Explore the most affordable flight options available from United Kingdom to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 1, 2025.

This Finnair deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Finnair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/182:45 pmLGW - ONT
2 stops31h 07mMultiple Airlines
Sat 5/2410:40 pmONT - LGW
2 stops25h 10mMultiple Airlines
Deal found 4/30$521
This American Airlines deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/133:05 pmLGW - ONT
2 stops28h 45mAmerican Airlines
Sun 6/111:59 pmONT - LGW
2 stops24h 11mAmerican Airlines
Deal found 4/30$523
This British Airways deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/87:50 amLHR - ONT
2 stops22h 08mBritish Airways
Thu 5/226:15 amONT - LHR
1 stop20h 35mBritish Airways
Deal found 4/30$540
This TravelUp deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure TravelUp is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/810:55 amLHR - ONT
1 stop13h 22mKLM
Mon 5/121:10 pmONT - LHR
1 stop12h 40mKLM
Deal found 4/30$560
This United Airlines deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/151:40 pmLHR - ONT
1 stop16h 20mUnited Airlines
Fri 5/231:36 pmONT - LHR
1 stop12h 49mUnited Airlines
Deal found 4/30$564
This Iberia deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Iberia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/109:15 amLHR - ONT
2 stops22h 21mIberia
Wed 9/1712:49 pmONT - LHR
1 stop14h 01mIberia
Deal found 4/30$566
This Delta deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/289:55 amLHR - ONT
2 stops20h 40mDelta
Wed 6/117:05 amONT - LHR
2 stops17h 45mDelta
Deal found 4/30$570
This CheapTickets.ch deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapTickets.ch is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/118:20 amLHR - ONT
1 stop17h 20mFinnair
Sun 9/2112:49 pmONT - LHR
1 stop14h 01mFinnair
Deal found 4/30$612
This Trip.com deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/111:25 pmLHR - ONT
1 stop17h 16mVirgin Atlantic
Tue 9/3011:29 amONT - LHR
1 stop15h 51mVirgin Atlantic
Deal found 4/30$619
This World Air Fares deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure World Air Fares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/2912:05 pmLHR - ONT
1 stop16h 16mLufthansa
Wed 11/191:00 pmONT - LHR
1 stop12h 40mLufthansa
Deal found 4/30$638
This Delta deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/68:40 amLCY - ONT
2 stops21h 55mDelta
Sun 6/85:08 pmONT - LCY
2 stops15h 32mDelta
Deal found 4/30$641
This British Airways deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/108:00 amMAN - ONT
2 stops23h 36mBritish Airways
Wed 9/178:43 amONT - MAN
2 stops20h 27mBritish Airways
Deal found 4/30$660

Cheapflights Fare Finder

Customize your flight search to find flights from United Kingdom to Ontario that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated May 1, 2025.
Use the filters below to find and compare flights from the United Kingdom to Ontario that are best for you.

Fly from

United Kingdom

Fly to

Ontario

Route

Depart

Return

Price

LondonOntario

LGW - ONT

LGWONT

London Gatwick

Sun 5/18

2:45 pm-1:52 pm

2 stops31h 07m

Ontario

Sat 5/24

10:40 pm-7:50 am

2 stops25h 10m

$521

LondonOntario

LGW - ONT

LGWONT

London Gatwick

Tue 5/13

3:05 pm-11:50 am

2 stops28h 45m

Ontario

Sun 6/1

11:59 pm-8:10 am

2 stops24h 11m

$523

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sat 5/10

2:50 pm-8:53 pm

1 stop14h 03m

Ontario

Sat 5/17

1:20 pm-9:40 am

1 stop12h 20m

$540

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Fri 6/6

10:30 am-7:01 pm

1 stop16h 31m

Ontario

Sun 6/8

8:15 am-9:00 am

1 stop16h 45m

$557

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Tue 5/13

10:55 am-4:17 pm

1 stop13h 22m

Ontario

Tue 8/5

1:15 pm-9:50 am

1 stop12h 35m

$561

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 5/14

2:50 pm-8:53 pm

1 stop14h 03m

Ontario

Tue 5/20

3:10 pm-2:10 pm

1 stop15h 00m

$562

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 9/10

9:15 am-11:36 pm

2 stops22h 21m

Ontario

Wed 9/17

12:49 pm-10:50 am

1 stop14h 01m

$566

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 5/28

9:55 am-10:35 pm

2 stops20h 40m

Ontario

Wed 6/11

7:05 am-8:50 am

2 stops17h 45m

$570

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Thu 9/11

8:20 am-5:40 pm

1 stop17h 20m

Ontario

Sun 9/21

12:49 pm-10:50 am

1 stop14h 01m

$612

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 8/11

1:25 pm-10:41 pm

1 stop17h 16m

Ontario

Tue 9/30

11:29 am-11:20 am

1 stop15h 51m

$619

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/29

Showing 1-10 of 60 results
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Best time to book a flight from United Kingdom to Ontario

Have a flexible travel schedule? Discover the best time to fly to Ontario from United Kingdom with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from the United Kingdom to Ontario

What is the cheapest month to book a flight from United Kingdom to Ontario?

Currently, August is the cheapest month in which you can book a flight from United Kingdom to Ontario (average of $246). Flying from United Kingdom to Ontario in March is currently the most expensive (average of $328). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from GB to ONT?

Find hourly flight availability from United Kingdom to Ontario. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated May 1, 2025.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from United Kingdom to Ontario as you normally would.

Rainfall in Ontario by month

Plan your trip to Ontario by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Ontario ranges from 0.1 - 3.4 inches per month. February is typically the wettest month, when rainfall can reach 3.4 in. June is typically the driest time to visit Ontario when rainfall is around 0.1 in.

Temperature in Ontario by month

Plan your trip to Ontario by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Ontario, use this chart to help with planning. For those seeking warmer temperatures, August is the ideal time of year to visit, when temperatures reach an average of 78.8 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 53.6 F).

Reviews of airlines servicing Ontario

Get insights into the airlines that provide service to Ontario. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Ontario. Reviews last updated May 1, 2025.
To help decide which airline to fly from United Kingdom to Ontario, see what other customers have to say about Delta, KLM and Finnair. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
7,934 reviews

Food

7.3

Boarding

8.2

Crew

8.5

Comfort

7.9

Overall

8.0

Entertainment

7.9

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Delta
8.0
Very good
7,934 reviews
Delta
8.0
Very good
7,934 reviews

Food

7.3

Boarding

8.2

Crew

8.5

Comfort

7.9

Overall

8.0

Entertainment

7.9

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
KLM
7.8
Good
1,334 reviews
Delta
8.0
Very good
7,934 reviews

Food

7.3

Boarding

8.2

Crew

8.5

Comfort

7.9

Overall

8.0

Entertainment

7.9

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Finnair
7.6
Good
1,275 reviews
Delta
8.0
Very good
7,934 reviews

Food

7.3

Boarding

8.2

Crew

8.5

Comfort

7.9

Overall

8.0

Entertainment

7.9

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Air France
7.4
Good
1,446 reviews
Delta
8.0
Very good
7,934 reviews

Food

7.3

Boarding

8.2

Crew

8.5

Comfort

7.9

Overall

8.0

Entertainment

7.9

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
United Airlines
7.4
Good
8,696 reviews
Delta
8.0
Very good
7,934 reviews

Food

7.3

Boarding

8.2

Crew

8.5

Comfort

7.9

Overall

8.0

Entertainment

7.9

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

Related info for your journey

Find useful and relevant information for your journey from United Kingdom to Ontario. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly into for flights to Ontario from United Kingdom?

    If you book a flight to Ontario from United Kingdom, you will be flying to Ontario, which is the city’s only airport. Ontario (ONT) is located 3.1 mi from the center of Ontario.

  • What are the cheapest airlines to fly from United Kingdom to Ontario one-way?

    The cheapest airline one-way is British Airways, with whom users have recently found tickets for as low as $573. However, be on the lookout for offers from Lufthansa and Iberia, as they are both options that can get you from United Kingdom to Ontario for a low price.

  • What are the most popular routes from United Kingdom to Ontario?

    Most travelers choose London Heathrow - Ontario, Manchester - Ontario or London Gatwick - Ontario when deciding on the best route from United Kingdom to Ontario.

  • Can I find deals for flights from United Kingdom to Ontario that include hotel bookings?

    Yes. In addition to deals on United Kingdom to Ontario flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from United Kingdom to Ontario?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from United Kingdom to Ontario.

  • Can I find deals for business class flights from United Kingdom to Ontario?

    Yes. Cheapflights offers flight deals from United Kingdom to Ontario by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from United Kingdom to Ontario?

    Currently, August is the cheapest month in which you can book a flight from United Kingdom to Ontario (average of $246). Flying from United Kingdom to Ontario in March is currently the most expensive (average of $328). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

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Alternative routes for United Kingdom to Ontario

See prices for flight routes from nearby airports that may be better suited for you.
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Top airline flying from United Kingdom to Ontario

Discover the top airline that operate flights from United Kingdom to Ontario. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated May 1, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$662Average$836FlexibilityNo cancel feeOn-time69%

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