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Cheap flights from the United Kingdom to Ontario from £392

This is the cheapest retur flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 24/8. Fares are subject to change and may not be available on all flights or dates of travel.
LHR — ONT
13 Jul — 20 Jul1
1 adult

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 8 July 2025.

Round-trip from

£392

Popular in

August

Cheapest in

February

Average price

£582
KLM
  • KLM
  • 24/8-9/9
  • 2 total stops
  • 39h 20m total
  • United Kingdom to Ontario
Highest demand for flights based on searches. 9% potential increase in price (£38 potential increase over avg. return price).
Cheapest flight prices on average. 2% potential price decrease (£9 potential savings vs. average return price).
Average for round-trip flights in July 2025

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 8 July 2025.

Sun 24/810:55LHR - ONT
1 stop20h 45mKLM
Tue 9/911:40ONT - LHR
1 stop18h 35mKLM
Deal found 7/7£392
Thu 28/815:05LGW - ONT
2 stops28h 27mMultiple Airlines
Wed 10/906:10ONT - LGW
2 stops18h 00mMultiple Airlines
Deal found 6/7£413
Sun 24/810:55LHR - ONT
1 stop20h 45mVirgin Atlantic
Tue 9/906:05ONT - LHR
2 stops40h 20mVirgin Atlantic
Deal found 7/7£416
Sun 31/815:10LHR - ONT
1 stop15h 04mFinnair
Sat 13/914:54ONT - LHR
1 stop13h 51mFinnair
Deal found 6/7£419
Fri 26/912:00LHR - ONT
1 stop14h 54mBritish Airways
Wed 8/1016:49ONT - LHR
1 stop12h 01mBritish Airways
Deal found 8/7£425
Mon 24/1119:05LHR - ONT
2 stops22h 23mIberia
Fri 5/1210:57ONT - LHR
1 stop15h 03mIberia
Deal found 7/7£428
Tue 25/1106:30LHR - ONT
2 stops24h 12mDelta
Fri 5/1211:29ONT - LHR
1 stop15h 31mDelta
Deal found 7/7£430
Mon 1/915:40LHR - ONT
1 stop13h 59mAmerican Airlines
Wed 17/916:45ONT - LHR
1 stop12h 05mAmerican Airlines
Deal found 8/7£443
Wed 3/912:00LHR - ONT
1 stop14h 54mMultiple Airlines
Tue 9/912:45ONT - LHR
1 stop14h 05mMultiple Airlines
Deal found 6/7£476
Wed 19/1105:55MAN - ONT
2 stops25h 51mVirgin Atlantic
Tue 2/1206:00ONT - MAN
2 stops26h 35mVirgin Atlantic
Deal found 7/7£509
Wed 5/1109:15NCL - ONT
2 stops45h 27mVirgin Atlantic
Sun 9/1112:00ONT - NCL
2 stops41h 10mVirgin Atlantic
Deal found 6/7£522
Tue 25/1112:00MAN - ONT
1 stop18h 41mDelta
Tue 2/1222:59ONT - MAN
1 stop24h 56mDelta
Deal found 7/7£524

Cheapflights Fare Finder

Customise 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 858,174 searches. Data last updated 8 July 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

LHR - ONT

LHRONT

London Heathrow

Sun 24/8

10:55-23:40

1 stop20h 45m

Ontario

Tue 9/9

11:40-14:15

1 stop18h 35m

£392

LondonOntario

LGW - ONT

LGWONT

London Gatwick

Thu 28/8

15:05-11:32

2 stops28h 27m

Ontario

Wed 10/9

06:10-08:10

2 stops18h 00m

£413

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sun 24/8

10:55-23:40

1 stop20h 45m

Ontario

Tue 9/9

06:05-06:25

2 stops40h 20m

£416

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Sun 31/8

15:10-22:14

1 stop15h 04m

Ontario

Sat 13/9

14:54-12:45

1 stop13h 51m

£419

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Fri 26/9

12:00-18:54

1 stop14h 54m

Ontario

Wed 8/10

16:49-12:50

1 stop12h 01m

£425

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 24/11

19:05-09:28

2 stops22h 23m

Ontario

Fri 5/12

10:57-10:00

1 stop15h 03m

£428

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Tue 25/11

06:30-22:41

2 stops24h 11m

Ontario

Fri 5/12

06:00-12:15

2 stops22h 15m

£430

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Mon 1/9

15:40-21:39

1 stop13h 59m

Ontario

Wed 17/9

16:45-12:50

1 stop12h 05m

£443

LondonOntario

LHR - ONT

LHRONT

London Heathrow

Wed 3/9

12:00-18:54

1 stop14h 54m

Ontario

Tue 9/9

12:45-10:50

1 stop14h 05m

£476

ManchesterOntario

MAN - ONT

MANONT

Manchester

Wed 19/11

05:55-23:46

2 stops25h 51m

Ontario

Tue 2/12

06:00-16:35

2 stops26h 35m

£509

Flights are sorted by cheapest return flights first.

Deals found on 7/7

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 return 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, March is the cheapest month in which you can book a flight from United Kingdom to Ontario (average of £516). Flying from United Kingdom to Ontario in August is currently the most expensive (average of £827). 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 8 July 2025.

When flying from United Kingdom to Ontario, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

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 8 July 2025.
Read through reviews of airlines operating flights from the United Kingdom to Ontario, such as Delta, KLM, andFinnair. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.

Crew

8.5

Overall

8.0

Boarding

8.2

Food

7.3

Comfort

7.9

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
8.0
Very Good

Crew

8.5

Overall

8.0

Boarding

8.2

Food

7.3

Comfort

7.9

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

Crew

8.5

Overall

8.0

Boarding

8.2

Food

7.3

Comfort

7.9

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

Crew

8.5

Overall

8.0

Boarding

8.2

Food

7.3

Comfort

7.9

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

Crew

8.5

Overall

8.0

Boarding

8.2

Food

7.3

Comfort

7.9

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

Crew

8.5

Overall

8.0

Boarding

8.2

Food

7.3

Comfort

7.9

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?

    Located just 3.1 mi from the city center, Ontario (ONT) is the airport most travelers will use when flying to Ontario from United Kingdom.

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

    The cheapet airlines for a one-way flight from United Kingdom to Ontario are British Airways (£435), WestJet (£488), and Iberia (£489).

  • What are the most popular routes 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 holiday 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, March is the cheapest month in which you can book a flight from United Kingdom to Ontario (average of £516). Flying from United Kingdom to Ontario in August is currently the most expensive (average of £827). 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

Browse thousands of different options on Cheapflights for your next trip

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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.

Top 6 airlines flying from United Kingdom to Ontario

Discover the top 6 airlines 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 858,174 searches. Data last updated 8 July 2025.
AirlineCheapestAverageFlexibilityOn-time
FinnairCheapest£275Average£423FlexibilityNo cancel feeOn-time76%
Search Finnair flights
British AirwaysCheapest£373Average£532FlexibilityNo cancel feeOn-time70%
Search British Airways flights
KLMCheapest£373Average£592FlexibilityNo cancel feeOn-time75%
Search KLM flights
United AirlinesCheapest£390Average£581FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
Virgin AtlanticCheapest£401Average£505FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights
LufthansaCheapest£425Average£547FlexibilityNo cancel feeOn-time76%
Search Lufthansa flights

Fly with Cheapflights

Find the best flight deals on Cheapflights, where travellers can enjoy low prices and a wide availability of flights to their desired destinations.

How does Cheapflights help users find flights from United Kingdom to Ontario?

Deals for United Kingdom to Ontario flights are sourced from 900+ travel sites when you use Cheapflights. When all flight results come back, Cheapflights lets you sort and filter flights using different criteria to choose better, like price, airport, cabin class, and plenty of other options.

Why should you use Cheapflights to find cheap flight tickets from United Kingdom to Ontario?

Cheapflights simply makes it quick and affordable to book flights from United Kingdom to Ontario by bringing together all flight options from hundreds of airlines and agencies online — and put it in one place for you to choose from. Plus, Cheapflights is 100% free to use for all.

Can Cheapflights find flights from United Kingdom to Ontario with no change fees?

Need flexible booking options for your flight to Ontario from United Kingdom? Don’t worry, Cheapflights have you covered. Use our search filter to only show flights with no change fees.

Can Cheapflights notify me if prices for flights from United Kingdom to Ontario become cheaper?

Yes, Cheapflights has a feature called Price Alert, which notifies users when flight prices change. Track prices for your flight to Ontario from United Kingdom today and book when prices fit your budget.

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